Science.gov

Sample records for energy end-use flow

  1. Healthcare Energy End-Use Monitoring

    SciTech Connect

    Sheppy, M.; Pless, S.; Kung, F.

    2014-08-01

    NREL partnered with two hospitals (MGH and SUNY UMU) to collect data on the energy used for multiple thermal and electrical end-use categories, including preheat, heating, and reheat; humidification; service water heating; cooling; fans; pumps; lighting; and select plug and process loads. Additional data from medical office buildings were provided for an analysis focused on plug loads. Facility managers, energy managers, and engineers in the healthcare sector will be able to use these results to more effectively prioritize and refine the scope of investments in new metering and energy audits.

  2. Energy end-use intensities in commercial buildings

    SciTech Connect

    Not Available

    1994-09-01

    This report examines energy intensities in commercial buildings for nine end uses: space heating, cooling, ventilation, lighting, water heating, cooking, refrigeration, office equipment, and other. The objective of this analysis was to increase understanding of how energy is used in commercial buildings and to identify targets for greater energy efficiency which could moderate future growth in demand. The source of data for the analysis is the 1989 Commercial Buildings Energy Consumption survey (CBECS), which collected detailed data on energy-related characteristics and energy consumption for a nationally representative sample of approximately 6,000 commercial buildings. The analysis used 1989 CBECS data because the 1992 CBECS data were not yet available at the time the study was initiated. The CBECS data were fed into the Facility Energy Decision Screening (FEDS) system, a building energy simulation program developed by the US Department of Energy`s Pacific Northwest Laboratory, to derive engineering estimates of end-use consumption for each building in the sample. The FEDS estimates were then statistically adjusted to match the total energy consumption for each building. This is the Energy Information Administration`s (EIA) first report on energy end-use consumption in commercial buildings. This report is part of an effort to address customer requests for more information on how energy is used in buildings, which was an overall theme of the 1992 user needs study. The end-use data presented in this report were not available for publication in Commercial Buildings Energy Consumption and Expenditures 1989 (DOE/EIA-0318(89), Washington, DC, April 1992). However, subsequent reports on end-use energy consumption will be part of the Commercial Buildings Energy Consumption and Expenditures series, beginning with a 1992 data report to be published in early 1995.

  3. Energy end-use model of the Jordanian SMES industries

    NASA Astrophysics Data System (ADS)

    Al-Bashir, Adnan; Al-Ghandoor, Ahmed; Abdallat, Yousef; Al-Hadethi, Rami

    2012-11-01

    In this paper, an energy end-use model of the Jordanian SMEs industries is presented. The industrial sector in Jordan consumes about 23% of the country's total energy. To establish the end-use model, a survey covering 150 facilities of different types of industries was conducted. The results show that the main electricity end-use consumers are electrical motors with a share of 55% of the total electricity consumption. On the other hand, fossil fuel is mainly used for hot water and steam generation with diesel fuel as a dominant fuel. The results of the study can be considered as an insight into the energy usage pattern of the Jordanian industrial sector for the policy maker. Furthermore, the results could provide important guidelines and insights for future research and development allocations and energy projects.

  4. United States Industrial Sector Energy End Use Analysis

    SciTech Connect

    Shehabi, Arman; Morrow, William R.; Masanet, Eric

    2012-05-11

    The United States Department of Energy’s (DOE) Energy Information Administration (EIA) conducts the Manufacturing Energy Consumption Survey (MECS) to provide detailed data on energy consumption in the manufacturing sector. The survey is a sample of approximately 15,000 manufacturing establishments selected from the Economic Census - Manufacturing Sector. MECS provides statistics on the consumption of energy by end uses (e.g., boilers, process, electric drives, etc.) disaggregated by North American Industry Classification System (NAICS) categories. The manufacturing sector (NAICS Sector 31-33) consists of all manufacturing establishments in the 50 States and the District of Columbia. According to the NAICS, the manufacturing sector comprises establishments engaged in the mechanical, physical, or chemical transformation of materials, substances, or components into new products. The establishments are physical facilities such as plants, factories, or mills. For many of the sectors in the MECS datasets, information is missing because the reported energy use is less than 0.5 units or BTUs, or is withheld to avoid disclosing data for individual establishments, or is withheld because the standard error is greater than 50%. We infer what the missing information likely are using several approximations techniques. First, much of the missing data can be easily calculated by adding or subtracting other values reported by MECS. If this is not possible (e.g. two data are missing), we look at historic MECS reports to help identify the breakdown of energy use in the past and assume it remained the same for the current MECS. Lastly, if historic data is also missing, we assume that 3 digit NAICS classifications predict energy use in their 4, 5, or 6 digit NAICS sub-classifications, or vice versa. Along with addressing data gaps, end use energy is disaggregated beyond the specified MECS allocations using additional industry specific energy consumption data. The result is a

  5. Energy end-use requirements in manufacturing, volume 1

    NASA Astrophysics Data System (ADS)

    Limaye, D. R.; Isser, S.; Beatty, R.; Colville, G.; Lang, K.; Krawiec, F.

    1981-07-01

    A review and evaluation of existing industrial energy data bases were undertaken to assess their potential for supporting SERI research to analyze technical and economic feasibility of solar technologies, and to establish multilayer R and D programs for: solar thermal industrial electric power systems and solar IPH systems. In the review of existing industrial energy data bases, the level of detail, disaggregation, and primary sources of information were examined. The focus was on fuels and electric energy used for heat and power purchased by the manufacturing subsector and listed by 2-, 3-, and 4-digit SIC, primary fuel, and end use.

  6. Commercial building end-use energy metering inventory

    SciTech Connect

    Heidell, J.A.; Mazzucchi, R.P.; Reilly, R.W.

    1985-03-01

    Pacific Northwest Laboratory conducted a comprehensive inventory of end-use metered data. The inventory did not discover many sources of metered end-use data; however, research into existing data bases and extensive discussions with professionals associated with building energy conservation have enabled a clear characterization to be developed of the types of metered data that are required to further energy conservation in commercial buildings. Based on the results of the inventory and this clarification of data requirements, the adequacy of existing data bases has been assessed, and recommendations have been developed for future federal data collection efforts. A summary of sources of existing metered end-use data is provided in Section 2.1 and its adequacy has been summarized. Collection of further end-use metered data is both desirable and valuable for many areas of building energy conservation research. Empirical data are needed to address many issues which to date have been addressed using only simulation techniques. The adequacy of using simulation techniques for various purposes needs to be assessed through comparison with measured data. While these data are expensive to acquire, it is cost-effective to do so in the long run, and the need is not being served by the private market. The preceding conclusion based on results from the inventory of existing data highlights two important facts: First, although the data are widely desired in the private sector, they are not widely available. Second, where suitable data are publicly available and contain the desired supporting information, their collection has generally been funded by government-sponsored research.

  7. India Energy Outlook: End Use Demand in India to 2020

    SciTech Connect

    de la Rue du Can, Stephane; McNeil, Michael; Sathaye, Jayant

    2009-03-30

    Integrated economic models have been used to project both baseline and mitigation greenhouse gas emissions scenarios at the country and the global level. Results of these scenarios are typically presented at the sectoral level such as industry, transport, and buildings without further disaggregation. Recently, a keen interest has emerged on constructing bottom up scenarios where technical energy saving potentials can be displayed in detail (IEA, 2006b; IPCC, 2007; McKinsey, 2007). Analysts interested in particular technologies and policies, require detailed information to understand specific mitigation options in relation to business-as-usual trends. However, the limit of information available for developing countries often poses a problem. In this report, we have focus on analyzing energy use in India in greater detail. Results shown for the residential and transport sectors are taken from a previous report (de la Rue du Can, 2008). A complete picture of energy use with disaggregated levels is drawn to understand how energy is used in India and to offer the possibility to put in perspective the different sources of end use energy consumption. For each sector, drivers of energy and technology are indentified. Trends are then analyzed and used to project future growth. Results of this report provide valuable inputs to the elaboration of realistic energy efficiency scenarios.

  8. Residential End-use Energy Planning System (REEPS)

    NASA Astrophysics Data System (ADS)

    Goett, A.; McFadden, D.

    1982-07-01

    The Residential End-Use Energy Planning System (REEPS) is described. REEPS is a forecasting model of residential energy patterns that is capable of evaluating the impacts of a broad range of energy conservation measures. REEPS forecasts appliance installations, operating efficiencies, and utilization patterns for space heating, water heating, air conditioning, and cooking. Each of these decisions is sensitive to energy prices, mandatory policies, and household/dwelling and geographical characteristics. The parameters of these choice models have been estimated statistically from national household survey data. The structure of the choice models and the results of the statistical analysis are reported in detail. REEPS forecasts energy choices for a large number of market segments representing households with different socioeconomic, dwelling, and geographical characteristics. These segments reflect the joint distribution of characteristics in the population. Aggregate forecasts are generated by summing up the decisions for all population segments. This technique provides a consistent method of obtaining aggregate forecasts from disaggregate, nonlinear choice models. Moreover, it permits evaluation of the distributional impacts of prospective conservation policies. The results of simulation of REEPS are described.

  9. End use energy consumption data base: transportation sector

    SciTech Connect

    Hooker, J.N.; Rose, A.B.; Greene, D.L.

    1980-02-01

    The transportation fuel and energy use estimates developed a Oak Ridge National Laboratory (ORNL) for the End Use Energy Consumption Data Base are documented. The total data base contains estimates of energy use in the United States broken down into many categories within all sectors of the economy: agriculture, mining, construction, manufacturing, commerce, the household, electric utilities, and transportation. The transportation data provided by ORNL generally cover each of the 10 years from 1967 through 1976 (occasionally 1977 and 1978), with omissions in some models. The estimtes are broken down by mode of transport, fuel, region and State, sector of the economy providing transportation, and by the use to which it is put, and, in the case of automobile and bus travel, by the income of the traveler. Fuel types include natural gas, motor and aviation gasoline, residual and diesel oil, liuqefied propane, liquefied butane, and naphtha- and kerosene-type jet engine fuels. Electricity use is also estimated. The mode, fuel, sector, and use categories themselves subsume one, two, or three levels of subcategories, resulting in a very detailed categorization and definitive accounting.

  10. Energy End-Use Patterns in Full-Service Hotels: A Case Study

    SciTech Connect

    Placet, Marylynn; Katipamula, Srinivas; Liu, Bing; Dirks, James A.; Xie, YuLong; Sullivan, Greg; Walent, Jim; Williamson, Rebecca

    2010-06-30

    The U.S. Department of Energy (DOE) recently initiated a program -- Commercial Building Partnerships (CBP) -- to work with private-sector companies in the design of highly-efficient retrofit and new construction projects. Pacific Northwest National Laboratory (PNNL) is conducting a project with a major hotel company to retrofit a full-service, large hotel with the goal of reducing energy consumption by at least 30%. The first step of the project was an intensive metering and monitoring effort aimed at understanding energy end use patterns in the hotel. About 10% of the guest rooms (32), as well as circuits for most of the end uses in public spaces (lighting, elevators, air handlers and other HVAC system components, and various equipment), were equipped with meters. Data are being collected at 1- or 5-minute intervals and downloaded on a monthly basis for analysis. This paper presents results from the first four months of the monitoring effort, which revealed energy end-use consumption patterns, variability of guest room energy use, daily load curves, monthly variations, and other aspects of hotel energy use. Metered end-use data for hotels at this level of detail are not available from any currently-available public sources. This study presents unique information and insight into energy end-use patterns in the lodging sector of commercial buildings and can also serve as a case study of a complex sub-metering project.

  11. A new approach to estimate commercial sector end-use load shapes and energy use intensities

    SciTech Connect

    Akbari, H.; Eto, J.; Konopacki, S.; Afzal, A.; Heinemeier, K.; Rainer, L.

    1994-08-01

    We discuss the application of an end-use load shape estimation technique to develop annual energy use intensities (EUIs) and hourly end-use load shapes (LSs) for commercial buildings in the Pacific Gas and Electric Company (PG&E) service territory. Results will update inputs for the commercial sector energy and peak demand forecasting models used by PG&E and the California Energy Commission (CEC). EUIs were estimated for 11 building types, up to 10 end uses, 3 fuel types, 2 building vintages, and up to 5 climate regions. The integrated methodology consists of two major parts. The first part is the reconciliation of initial end-use load-shape estimates with measured whole-building load data to produce intermediate EUIs and load shapes, using LBL`s End-use Disaggregation Algorithm, EDA. EDA is a deterministic hourly algorithm that relies on the observed characteristics of the measured hourly whole-building electricity use and disaggregates it into major end-use components. The end-use EUIs developed through the EDA procedure represent a snap-shot of electricity use by building type and end-use for two regions of the PG&E service territory, for the year that disaggregation is performed. In the second part of the methodology, we adjust the EUIs for direct application to forecasting models based on factors such as climatic impacts on space-conditioning EUIs, fuel saturation effects, building and equipment vintage, and price impacts. Core data for the project are detailed on-site surveys for about 800 buildings, mail surveys ({approximately}6000), load research data for over 1000 accounts, and hourly weather data for five climate regions.

  12. Project on restaurant energy performance: end-use monitoring and analysis. Appendixes I and II

    SciTech Connect

    Claar, C.N.; Mazzucchi, R.P.; Heidell, J.A.

    1985-05-01

    This is the second volume of the report, ''The Porject on Restaurant Energy Performance - End-Use Monitoring and Analysis''. The first volume (PNL-5462) contains a summary and analysis of the metered energy performance data collected by the Project on Restaurant Energy Performance (PREP). Appendix I, presented here, contains monitoring site descriptions, measurement plans, and data summaries for the seven restaurants metered for PREP. Appendix II, also in this volume, is a description of the PREP computer system.

  13. Mapping the global flow of steel: from steelmaking to end-use goods.

    PubMed

    Cullen, Jonathan M; Allwood, Julian M; Bambach, Margarita D

    2012-12-18

    Our society is addicted to steel. Global demand for steel has risen to 1.4 billion tonnes a year and is set to at least double by 2050, while the steel industry generates nearly a 10th of the world's energy related CO₂ emissions. Meeting our 2050 climate change targets would require a 75% reduction in CO₂ emissions for every tonne of steel produced and finding credible solutions is proving a challenge. The starting point for understanding the environmental impacts of steel production is to accurately map the global steel supply chain and identify the biggest steel flows where actions can be directed to deliver the largest impact. In this paper we present a map of global steel, which for the first time traces steel flows from steelmaking, through casting, forming, and rolling, to the fabrication of final goods. The diagram reveals the relative scale of steel flows and shows where efforts to improve energy and material efficiency should be focused.

  14. Marginalization of end-use technologies in energy innovation for climate protection

    NASA Astrophysics Data System (ADS)

    Wilson, Charlie; Grubler, Arnulf; Gallagher, Kelly S.; Nemet, Gregory F.

    2012-11-01

    Mitigating climate change requires directed innovation efforts to develop and deploy energy technologies. Innovation activities are directed towards the outcome of climate protection by public institutions, policies and resources that in turn shape market behaviour. We analyse diverse indicators of activity throughout the innovation system to assess these efforts. We find efficient end-use technologies contribute large potential emission reductions and provide higher social returns on investment than energy-supply technologies. Yet public institutions, policies and financial resources pervasively privilege energy-supply technologies. Directed innovation efforts are strikingly misaligned with the needs of an emissions-constrained world. Significantly greater effort is needed to develop the full potential of efficient end-use technologies.

  15. Integrated estimation of commercial sector end-use load shapes and energy use intensities

    SciTech Connect

    Akbari, H.; Eto, J.; Turiel, I.; Heinemeier, K.; Lebot, B.; Nordman, B.; Rainer, L.

    1989-01-01

    The Southern California Edison Company (SCE) and the California Energy Commission (CEC) have contracted with the Energy Analysis Program of the Applied Science Division at the Lawrence Berkeley Laboratory (LBL) to develop an integrated set of commercial sector load shapes (LS) and energy utilization indices (EUI) for use in forecasting electricity demand. The objectives of this project are to conduct detailed analyses of SCE data on commercial building characteristics, energy use, and whole-building load shapes; and in conjunction with other data, to develop, test, and apply an integrated approach for the estimation of end-use LSs and EUIs. The project represents one of the first attempts to combine simulation-based, prototypical building analyses with direct reconciliation to measured hourly load data. The project examined electricity and gas use for nine building types, including large offices, small offices, large retails, small retails, food stores, sitdown restaurants, fastfood restaurants, refrigerated warehouses, and non-refrigerated warehouses. For each building type, nine end uses were examined, including cooling, heating, ventilation, indoor lighting, outdoor lighting, miscellaneous equipment, water heating, cooking, and refrigeration. For the HVAC end uses (cooling, ventilation, and heating), separate analyses were performed for three climate zones: coastal, inland, and desert.

  16. Project on Restaurant Energy Performance: end-use monitoring and analysis

    SciTech Connect

    Claar, C.N.; Mazzucchi, R.P.; Heidell, J.A.

    1985-05-01

    Although energy bills for restaurants throughout the United States exceed 5 billion dollars annually, very little has been documented with respect to when and how restaurants use energy, or how such use can be reduced cost-effectively. This report summarizes the results of a multiyear collaborative research effort, designed to collect information on end-use energy consumption. Objective is to reveal the quantities and profiles of energy consumption of typical food service operations by time of day and end use. This information, when examined in conjunction with building characteristics, allows detailed study of energy use cause and effect and energy conservation potential. Seven representative monitoring sites were selected, a computerized data acquisition network was designed and implemented, and detailed energy performance was compiled for a 1 year period (July 1983 through June 1984). Each of the seven facilities monitored was selected to represent the seven most common restaurant types and to provide information on a wide variety of commonly used restaurant equipment. Preliminary findings are presented.

  17. How many people actually see the price signal? Quantifying marketfailures in the end use of energy

    SciTech Connect

    Meier, Alan; Eide, Anita

    2007-09-01

    "Getting the price right" is a goal of many market-orientedenergy policies. However, there are situations where the consumer payingfor the energy is separate from the owner of the energy-using device.Economists call this a "principal agent problem". A team organised by theInternational Energy Agency examined seven end uses and one sector whereprincipal agent problems existed: refrigerators, water heating, spaceheating, vending machines, commercial HVAC, company cars, lighting, andfirms. These investigations took place in Australia, Japan, theNetherlands, Norway, and the United States. About 2 100 percent of theenergy consumed in the end uses examined was affected by principal agentproblems. The size (and sometimes even the existence) varied greatly fromone country to another but all countries had significant amounts ofenergy affected by principal agent problems. The presence of a marketfailure does not mean that energy use would fall substantially if thefailure were eliminated; however it does suggest that raising energyprices such as in the form of carbon taxes will not necessarily increaseefficiency investments.

  18. Project on restaurant energy performance end-use monitoring and analysis

    SciTech Connect

    Mazzucchi, R.P.

    1986-04-01

    This paper summarizes the results of a research program intended to build an understanding of restaurant energy performance upon an empirical foundation. This discussion provides some background for this effort, brief descriptions of the facilities selected for study, the measurement methods, the empirical findings, an overview of conservation opportunities revealed, and general conclusions. Seven monitoring sites were carefully selected to represent the most common categories of food service by the National Restaurant Association. A microcomputer based data acquisition was designed and implemented to acquire 15-minute interval data on end-use energy consumption, interior temperatures, and external climate conditions for a one year monitoring period. The project archived over 87% of the available data, which has been converted into several formats for dissemination. Restaurants are found to be very intensive users of energy due largely to the frequent usage of food preparation equipment and the high ventilation requirements.

  19. The project on restaurant energy performance end-use monitoring and analysis

    SciTech Connect

    Mazzucchi, R.P.

    1986-01-01

    This paper summarizes the results of a research program intended to build an understanding of restaurant energy performance upon an empirical foundation. This discussion provides some background for the effort, brief descriptions of the facilities selected for study, the methods of measurement, the empirical findings, an overview of conservation opportunities revealed, and general conclusions. Seven monitoring sites were carefully selected to represent the most common categories of food service by the National Restaurant Association. A microcomputer-based data acquisition was designed and implemented to acquire data at 15-minute intervals on end-use energy consumption, interior temperatures, and external climatic conditions for a one-year monitoring period. The project archived over 87% of the available data, which have been converted into several formats for dissemination.

  20. The Value of End-Use Energy Efficiency in Mitigation of U.S. Carbon Emissions

    SciTech Connect

    Kyle, G. Page; Smith, Steven J.; Clarke, Leon E.; Kim, Son H.; Wise, Marshall A.

    2007-11-27

    This report documents a scenario analysis exploring the value of advanced technologies in the U.S. buildings, industrial, and transportation sectors in stabilizing atmospheric greenhouse gas concentrations. The analysis was conducted by staff members of Pacific Northwest National Laboratory (PNNL), working at the Joint Global Change Research Institute (JGCRI) in support of the strategic planning process of the U.S. Department of Energy (U.S. DOE) Office of Energy Efficiency and Renewable Energy (EERE). The conceptual framework for the analysis is an integration of detailed buildings, industrial, and transportation modules into MiniCAM, a global integrated assessment model. The analysis is based on three technology scenarios, which differ in their assumed rates of deployment of new or presently available energy-saving technologies in the end-use sectors. These technology scenarios are explored with no carbon policy, and under two CO2 stabilization policies, in which an economic price on carbon is applied such that emissions follow prescribed trajectories leading to long-term stabilization of CO2 at roughly 450 and 550 parts per million by volume (ppmv). The costs of meeting the emissions targets prescribed by these policies are examined, and compared between technology scenarios. Relative to the reference technology scenario, advanced technologies in all three sectors reduce costs by 50% and 85% for the 450 and 550 ppmv policies, respectively. The 450 ppmv policy is more stringent and imposes higher costs than the 550 ppmv policy; as a result, the magnitude of the economic value of energy efficiency is four times greater for the 450 ppmv policy than the 550 ppmv policy. While they substantially reduce the costs of meeting emissions requirements, advanced end-use technologies do not lead to greenhouse gas stabilization without a carbon policy. This is due mostly to the effects of increasing service demands over time, the high consumption of fossil fuels in the

  1. The Role of End-Use in Integrated Urban Energy and Water System Dynamics

    NASA Astrophysics Data System (ADS)

    De Stercke, Simon; Mijic, Ana; Buytaert, Wouter

    2016-04-01

    The global trend of urbanisation is concentrating an increasing demand for services in cities, augmenting the global demand for resources such as freshwater and energy. At the same time, those resources are posing limits due to their availability or because their use is made prohibitive because of environmental pressures through e.g. global warming. Whereas planning for the provision of water and energy systems in cities has historically generally been separate, in the face of the present environmental challenges with important and intensifying socio-economic impacts, and because of their important interlinkages, both need to be integrated. The work presented introduces a combined urban energy/water model developed using system dynamics as a method, with an explicit and partially endogenous representation of the end-use demand. The model is used to illustrate how energy-related policies can affect the water sector and vice versa, the implications for planning of both systems which follow from that, and the important role demand side management plays. Data requirements are examined and the utility of the model to decisionmakers is discussed. The context of this work is the United Kingdom and London in particular, but changes to the model are suggested in order for it to apply to cities in other countries as well.

  2. Annual Energy Usage Reduction and Cost Savings of a School: End-Use Energy Analysis

    PubMed Central

    Alghoul, M. A.; Bakhtyar, B.; Asim, Nilofar; Sopian, K.

    2014-01-01

    Buildings are among the largest consumers of energy. Part of the energy is wasted due to the habits of users and equipment conditions. A solution to this problem is efficient energy usage. To this end, an energy audit can be conducted to assess the energy efficiency. This study aims to analyze the energy usage of a primary school and identify the potential energy reductions and cost savings. A preliminary audit was conducted, and several energy conservation measures were proposed. The energy conservation measures, with reference to the MS1525:2007 standard, were modelled to identify the potential energy reduction and cost savings. It was found that the school's usage of electricity exceeded its need, incurring an excess expenditure of RM 2947.42. From the lighting system alone, it was found that there is a potential energy reduction of 5489.06 kWh, which gives a cost saving of RM 2282.52 via the improvement of lighting system design and its operating hours. Overall, it was found that there is a potential energy reduction and cost saving of 20.7% when the energy conservation measures are earnestly implemented. The previous energy intensity of the school was found to be 50.6 kWh/m2/year, but can theoretically be reduced to 40.19 kWh/mm2/year. PMID:25485294

  3. Annual energy usage reduction and cost savings of a school: end-use energy analysis.

    PubMed

    Roslizar, Aiman; Alghoul, M A; Bakhtyar, B; Asim, Nilofar; Sopian, K

    2014-01-01

    Buildings are among the largest consumers of energy. Part of the energy is wasted due to the habits of users and equipment conditions. A solution to this problem is efficient energy usage. To this end, an energy audit can be conducted to assess the energy efficiency. This study aims to analyze the energy usage of a primary school and identify the potential energy reductions and cost savings. A preliminary audit was conducted, and several energy conservation measures were proposed. The energy conservation measures, with reference to the MS1525:2007 standard, were modelled to identify the potential energy reduction and cost savings. It was found that the school's usage of electricity exceeded its need, incurring an excess expenditure of RM 2947.42. From the lighting system alone, it was found that there is a potential energy reduction of 5489.06 kWh, which gives a cost saving of RM 2282.52 via the improvement of lighting system design and its operating hours. Overall, it was found that there is a potential energy reduction and cost saving of 20.7% when the energy conservation measures are earnestly implemented. The previous energy intensity of the school was found to be 50.6 kWh/m(2)/year, but can theoretically be reduced to 40.19 kWh/mm(2)/year. PMID:25485294

  4. Data on energy end-use patterns and energy efficiencies in major CO sub 2 emitting countries

    SciTech Connect

    Cheng, Hsing C.

    1990-08-01

    This is a report of the basic data regarding energy end-uses and efficiencies in major CO{sub 2} emitting countries. The task is part of the multi-lab carbon dioxide energy system research program. Fossil energy production and use are the largest anthropogenic source of CO{sub 2} emissions. To gain an insight into the relationship between CO{sub 2} emission and energy use, the global energy consumption patterns and the changing energy efficiencies must be better analyzed and understood. This work attempts to collect and organize the data on energy use and energy efficiency for the ten major CO{sub 2} emitting countries: USA, USSR, the People's Republic of China, Japan, the Federal Republic of Germany, the United Kingdom, France, Canada, Italy, and Australia. A wide variety of information sources have been examined. The data base is presented in tabular format. It is documented by three main parts, the first shows the total final energy consumption by fuel type and end-use sector for each nation. The second shows the detailed energy use by fuel type and function for each end-use sector: residential, commercial, transportation and industrial. The third part shows the country-specific energy balances for electricity generation and use. The data base is a living document and will be updated as additional information becomes available. The data base is to be used to accomplish the ultimate objective of improving the reliability of future CO{sub 2}-emissions estimates. 7 refs., 12 tabs.

  5. Optimal urban water conservation strategies considering embedded energy: coupling end-use and utility water-energy models.

    NASA Astrophysics Data System (ADS)

    Escriva-Bou, A.; Lund, J. R.; Pulido-Velazquez, M.; Spang, E. S.; Loge, F. J.

    2014-12-01

    Although most freshwater resources are used in agriculture, a greater amount of energy is consumed per unit of water supply for urban areas. Therefore, efforts to reduce the carbon footprint of water in cities, including the energy embedded within household uses, can be an order of magnitude larger than for other water uses. This characteristic of urban water systems creates a promising opportunity to reduce global greenhouse gas emissions, particularly given rapidly growing urbanization worldwide. Based on a previous Water-Energy-CO2 emissions model for household water end uses, this research introduces a probabilistic two-stage optimization model considering technical and behavioral decision variables to obtain the most economical strategies to minimize household water and water-related energy bills given both water and energy price shocks. Results show that adoption rates to reduce energy intensive appliances increase significantly, resulting in an overall 20% growth in indoor water conservation if household dwellers include the energy cost of their water use. To analyze the consequences on a utility-scale, we develop an hourly water-energy model based on data from East Bay Municipal Utility District in California, including the residential consumption, obtaining that water end uses accounts for roughly 90% of total water-related energy, but the 10% that is managed by the utility is worth over 12 million annually. Once the entire end-use + utility model is completed, several demand-side management conservation strategies were simulated for the city of San Ramon. In this smaller water district, roughly 5% of total EBMUD water use, we found that the optimal household strategies can reduce total GHG emissions by 4% and utility's energy cost over 70,000/yr. Especially interesting from the utility perspective could be the "smoothing" of water use peaks by avoiding daytime irrigation that among other benefits might reduce utility energy costs by 0.5% according to our

  6. Federal Financial Interventions and Subsidies in Energy Markets 1999: Energy Transformation and End Use

    EIA Publications

    2008-01-01

    his is the second report prepared in response to a two-part request from the Office of Policy, U.S. Department of Energy, to provide an estimate of U.S. Federal energy subsidies. In its request, the Office of Policy asked the Energy Information Administration (EIA) to update a 1992 EIA report on Federal energy subsidies, including any additions or deletions of Federal subsidies based on Administration and Congressional action since the 1992 report was written, and to provide an estimate of the size of each current subsidy.

  7. Beyond conventional energy use: A regionally based end-use approach for the twenty-first century

    NASA Astrophysics Data System (ADS)

    Feder, Deborah R.

    In the United States, the dominant energy discourse is supply-oriented and focused on the large-scale use of fossil fuel and nuclear electricity energy resources. Fossil fuels and nuclear electricity are valued for the convenience, quality of life, and services that they provide. Despite these qualities, the laws of thermodynamics tell us that fossil fuels and nuclear electricity are not required for all end-use needs. Concentrated high quality energy sources such as fossil fuels and electricity are degraded when used for tasks such as water and space heating. The degraded energy is released into the environment as waste heat and pollution and contribute to scarcity in many realms. This dissertation suggests an alternative discourse on energy that calls on three frameworks of thinking: the nexus of relations, end-use analysis, and regional geography. The nexus of relations is a device for showing how different relations in society construct uses of energy that lead most naturally to scarcity and environmental degradation. End-use analysis is a framework for matching energy sources and end-uses based on thermodynamic quality, and regional geography is useful for identifying localized renewable energy sources and end-use needs. By combining these three approaches, a new framework has been created that matches thermodynamically appropriate renewable resources to end-use needs. This approach offers a new perspective on resource use that emphasizes how energy demands can be met, while minimizing scarcity and environmental degradation. To illustrate this regionally based end-use framework, a case study was conducted at three sites within Centre County, Pennsylvania. At each study site, the flux density of solar, wind, and water resources was evaluated and matched with local end-use needs. This exercise resulted in several findings: one, fossil fuel/nuclear electricity savings are possible at each study site; two, geographically-specific renewable resources can be used to

  8. Public Health Benefits of End-Use Electrical Energy Efficiency in California: An Exploratory Study

    SciTech Connect

    McKone, Thomas E.; Lobscheid, A.B.

    2006-06-01

    This study assesses for California how increasing end-use electrical energy efficiency from installing residential insulation impacts exposures and disease burden from power-plant pollutant emissions. Installation of fiberglass attic insulation in the nearly 3 million electricity-heated homes throughout California is used as a case study. The pollutants nitrous oxides (NO{sub x}), sulfur dioxide (SO{sub 2}), fine particulate matter (PM2.5), benzo(a)pyrene, benzene, and naphthalene are selected for the assessment. Exposure is characterized separately for rural and urban environments using the CalTOX model, which is a key input to the US Environmental Protection Agency (EPA) Tool for the Reduction and Assessment of Chemicals and other environmental Impacts (TRACI). The output of CalTOX provides for urban and rural populations emissions-to-intake factors, which are expressed as an individual intake fraction (iFi). The typical iFi from power plant emissions are on the order of 10{sup -13} (g intake per g emitted) in urban and rural regions. The cumulative (rural and urban) product of emissions, population, and iFi is combined with toxic effects factors to determine human damage factors (HDFs). HDF are expressed as disability adjusted life years (DALYs) per kilogram pollutant emitted. The HDF approach is applied to the insulation case study. Upgrading existing residential insulation to US Department of Energy (DOE) recommended levels eliminates over the assmned 50-year lifetime of the insulation an estimated 1000 DALYs from power-plant emissions per million tonne (Mt) of insulation installed, mostly from the elimination of PM2.5 emissions. In comparison, the estimated burden from the manufacture of this insulation in DALYs per Mt is roughly four orders of magnitude lower than that avoided.

  9. Measured commercial load shapes and energy-use intensities and validation of the LBL end-use disaggregation algorithm

    SciTech Connect

    Akbari, H.; Rainer, L.; Heinemeier, K.; Huang, J.; Franconi, E.

    1993-01-01

    The Southern California Edison Company (SCE) has conducted an extensive metering project in which electricity end use in 53 commercial buildings in Southern California has been measured. The building types monitored include offices, retail stores, groceries, restaurants, and warehouses. One year (June 1989 through May 1990) of the SCE measured hourly end-use data are reviewed in this report. Annual whole-building and end-use energy use intensities (EUIs) and monthly load shapes (LSs) have been calculated for the different building types based on the monitored data. This report compares the monitored buildings' EUIs and LSs to EUIs and LSs determined using whole-building load data and the End-Use Disaggregation Algorithm (EDA). Two sets of EDA determined EUIs and LSs are compared to the monitored data values. The data sets represent: (1) average buildings in the SCE service territory and (2) specific buildings that were monitored.

  10. US energy flow, 1981

    NASA Astrophysics Data System (ADS)

    Briggs, C. K.; Borg, I. Y.

    1982-10-01

    Flow diagrams to describe the US energy situation are given. In 1981 the energy consumption was 73 quads (or 73 times 10 to the 15th power Btu). Use was down from 75 quads in 1980. Oil continues to dominate the picture as it comprises 45% of the total energy used. Net oil use (exclusive of oil purchased for the Strategic Petroleum Reserve and Exports) fell 8%; oil imports declined 14%. In contrast to oil, use of natural gas and coal remained at 1980 levels. Decreased use of residual oils, principally for electric power generating, account for much of the drop in oil use. Increased use of coal and nuclear energy for power generation almost compensated for the decrease in use of oil in that end use. Transmitted power remained at 1980 levels. The remainder of the drop in energy usage is attributed to price driven conservation, increased efficiencies in end use and the recession that prevailed during most of the year. The share of the energy drop attributable to the recession is estimated by various analysts to be on the order of 40 to 50%.

  11. Energy technology R and D: What could make a difference? Volume 2, Part 1 -- End-use technology

    SciTech Connect

    Sheffield, J.

    1997-09-01

    This report reviews the history and status of end use technologies and discusses the potential for new technologies and systems to reduce energy use. Environmental considerations are also important; they are not discussed explicitly in this report, but are implicitly taken into account in defining useful opportunities for improvement in energy use. A recent report (US DOE OEERE 1997), however, discusses technological paths to carbon emissions reductions in the 2010 time frame, and some of the conclusions from that study are presented. The conclusions about potential energy efficiency improvements are similar to those presented in this report. 52 figs., 54 tabs.

  12. Control Limits for Building Energy End Use Based on Engineering Judgment, Frequency Analysis, and Quantile Regression

    SciTech Connect

    Henze, G. P.; Pless, S.; Petersen, A.; Long, N.; Scambos, A. T.

    2014-02-01

    Approaches are needed to continuously characterize the energy performance of commercial buildings to allow for (1) timely response to excess energy use by building operators; and (2) building occupants to develop energy awareness and to actively engage in reducing energy use. Energy information systems, often involving graphical dashboards, are gaining popularity in presenting energy performance metrics to occupants and operators in a (near) real-time fashion. Such an energy information system, called Building Agent, has been developed at NREL and incorporates a dashboard for public display. Each building is, by virtue of its purpose, location, and construction, unique. Thus, assessing building energy performance is possible only in a relative sense, as comparison of absolute energy use out of context is not meaningful. In some cases, performance can be judged relative to average performance of comparable buildings. However, in cases of high-performance building designs, such as NREL's Research Support Facility (RSF) discussed in this report, relative performance is meaningful only when compared to historical performance of the facility or to a theoretical maximum performance of the facility as estimated through detailed building energy modeling.

  13. Understanding Superconducting Magnetic Energy Storage (SMES) technology, applications, and economics, for end-use workshop

    SciTech Connect

    Ferraro, R.J.; McConnell, B.W.

    1993-06-01

    The overall objective of this project was to determine the state-of-the-art and to what extent existing SMES is a viable option in meeting the needs of utilities and their customers for improving electric service power quality. By defining and analyzing SMES electrical/mechanical performance characteristics, and comparing SMES application benefits with competitive stored energy systems, industry will be able to determine SMES unique applications and potential market penetration. Building on this information base, it would also be possible to evaluate the impact of high temperature superconductors (77 K and 20-35 K) on SMES technology applications. The authors of this report constructed a network of industry contacts and research consultants that were used to collect, update, and analyze ongoing SMES R&D and marketing activities in industries, utilities, and equipment manufacturers. These key resources were utilized to assemble performance characteristics on existing SMES, battery, capacitor, flywheel, and high temperature superconductor (HTS) stored energy technologies. From this information, preliminary stored energy system comparisons were accomplished. In this way, the electric load needs would be readily comparable to the potential solutions and applications offered by each aforementioned energy storage technology.

  14. Changing Energy End-Use Patterns as a Means of Reducing Global-Warming Trends.

    ERIC Educational Resources Information Center

    Dresner, Marion

    1990-01-01

    A simulation game was used in an attempt to change undergraduates' behavior and attitudes toward energy conservation. Social influence was found to be correlated significantly with experimental treatment. Participants showed an increase in favorable attitudes toward activism and political efficacy, and exhibited a greater likelihood of taking…

  15. Energy balances in the production and end-use of methanol derived from coal

    SciTech Connect

    1980-12-10

    Analysis is performed for three combinations of fuels, specifically: net petroleum gain (petroleum only); net premium fuel gain (natural gas and petroleum); and net energy gain (includes all fuels; does not include free energy from sun). The base case selected for evaluation was that of an energy-efficient coal-to-methanol plant located in Montana/Wyoming and using the Lurgi conversion process. The following variations of the base coal-methanol case are also analyzed: gasoline from coal with methanol as an intermediate step (Mobil-M); and methanol from coal (Texaco gasification process). For each process, computations are made for the product methanol as a replacement for unleaded gasoline in a conventional spark ignition engine and as a chemical feedstock. For the purpose of the energy analysis, computations are made for three situations regarding mileage of methanol/ gasoline compared to that of regular unleaded gasoline: mileage of the two fuels equal, mileage 4 percent better with gasohol, and mileage 4 percent worse with gasohol. The standard methodology described for the base case applies to all of the variations.

  16. 2007 Estimated International Energy Flows

    SciTech Connect

    Smith, C A; Belles, R D; Simon, A J

    2011-03-10

    An energy flow chart or 'atlas' for 136 countries has been constructed from data maintained by the International Energy Agency (IEA) and estimates of energy use patterns for the year 2007. Approximately 490 exajoules (460 quadrillion BTU) of primary energy are used in aggregate by these countries each year. While the basic structure of the energy system is consistent from country to country, patterns of resource use and consumption vary. Energy can be visualized as it flows from resources (i.e. coal, petroleum, natural gas) through transformations such as electricity generation to end uses (i.e. residential, commercial, industrial, transportation). These flow patterns are visualized in this atlas of 136 country-level energy flow charts.

  17. The evolution of carbon dioxide emissions from energy use in industrialized countries: an end-use analysis

    SciTech Connect

    Schipper, L.; Ting, M.; Khrushch, M.; Unander, F.; Monahan, P.; Golove, W.

    1996-08-01

    There has been much attention drawn to plans for reductions or restraint in future C02 emissions, yet little analysis of the recent history of those emissions by end use or economic activity. Understanding the components of C02 emissions, particularly those related to combustion of fossil fuels, is important for judging the likely success of plans for dealing with future emissions. Knowing how fuel switching, changes in economic activity and its structure, or changes in energy-use efficiency affected emissions in the past, we can better judge both the realism of national proposals to restrain future emissions and the outcome as well. This study presents a first step in that analysis. The organization of this paper is as follows. We present a brief background and summarize previous work analyzing changes in energy use using the factorial method. We then describe our data sources and method. We then present a series of summary results, including a comparison of C02 emissions in 1991 by end use or sector. We show both aggregate change and change broken down by factor, highlighting briefly the main components of change. We then present detailed results, sector by sector. Next we highlight recent trends. Finally, we integrate our results, discussing -the most important factors driving change - evolution in economic structure, changes in energy intensities, and shifts in the fuel mix. We discuss briefly some of the likely causes of these changes - long- term technological changes, effects of rising incomes, the impact of overall changes in energy prices, as well as changes in the relative prices of energy forms.

  18. Large CO2 reductions via offshore wind power matched to inherent storage in energy end-uses

    NASA Astrophysics Data System (ADS)

    Kempton, Willett; Archer, Cristina L.; Dhanju, Amardeep; Garvine, Richard W.; Jacobson, Mark Z.

    2007-01-01

    We develop methods for assessing offshore wind resources, using a model of the vertical structure of the planetary boundary layer (PBL) over water and a wind-electric technology analysis linking turbine and tower limitations to bathymetry and continental shelf geology. These methods are tested by matching the winds of the Middle-Atlantic Bight (MAB) to energy demand in the adjacent states (Massachusetts through North Carolina, U.S.A.). We find that the MAB wind resource can produce 330 GW average electrical power, a resource exceeding the region's current summed demand for 73 GW of electricity, 29 GW of light vehicle fuels (now gasoline), and 83 GW of building fuels (now distillate fuel oil and natural gas). Supplying these end-uses with MAB wind power would reduce by 68% the region's CO2 emissions, and reduce by 57% its greenhouse gas forcing. These percentages are in the range of the global reductions needed to stabilize climate.

  19. End-use energy characterization and conservation potentials at DoD Facilities: An analysis of electricity use at Fort Hood, Texas

    SciTech Connect

    Akbari, H.; Konopacki, S.

    1995-05-01

    This report discusses the application of the LBL`s End-use Disaggregation Algorithm (EDA) to a DoD installation and presents hourly reconciled end-use data for all major building types and end uses. The project initially focused on achieving these objectives and pilot-testing the methodology at Fort Hood, Texas. Fort Hood, with over 5000 buildings was determined to have representative samples of nearly all of the major building types in use on DoD installations. These building types at Fort Hood include: office, administration, vehicle maintenance, shop, hospital, grocery store, retail store, car wash, church, restaurant, single-family detached housing, two and four-plex housings, and apartment building. Up to 11 end uses were developed for each prototype, consisting of 9 electric and 2 gas; however, only electric end uses were reconciled against known data and weather conditions. The electric end uses are space cooling, ventilation, cooking, miscellaneous/plugs, refrigeration, exterior lighting, interior lighting, process loads, and street lighting. The gas end uses are space heating and hot water heating. Space heating energy-use intensities were simulated only. The EDA was applied to 10 separate feeders from the three substations at Fort Hood. The results from the analyses of these ten feeders were extrapolated to estimate energy use by end use for the entire installation. The results show that administration, residential, and the bar-rack buildings are the largest consumers of electricity for a total of 250GWh per year (74% of annual consumption). By end use, cooling, ventilation, miscellaneous, and indoor lighting consume almost 84% of total electricity use. The contribution to the peak power demand is highest by residential sector (35%, 24 MW), followed by administration buildings (30%), and barrack (14%). For the entire Fort Hood installation, cooling is 54% of the peak demand (38 MW), followed by interior lighting at 18%, and miscellaneous end uses by 12%.

  20. Analyzing Residential End-Use Energy Consumption Data to Inform Residential Consumer Decisions and Enable Energy Efficiency Improvements

    NASA Astrophysics Data System (ADS)

    Carlson, Derrick R.

    While renewable energy is in the process of maturing, energy efficiency improvements may provide an opportunity to reduce energy consumption and consequent greenhouse gas emissions to bridge the gap between current emissions and the reductions necessary to prevent serious effects of climate change and will continue to be an integral part of greenhouse gas emissions policy moving forward. Residential energy is a largely untapped source of energy reductions as consumers, who wish to reduce energy consumption for monetary, environmental, and other reasons, face barriers. One such barrier is a lack of knowledge or understanding of how energy is consumed in a home and how to reduce this consumption effectively through behavioral and technological changes. One way to improve understanding of residential energy consumption is through the creation of a model to predict which appliances and electronics will be present and significantly contribute to the electricity consumption of a home on the basis of various characteristics of that home. The basis of this model is publically available survey data from the Residential Energy Consumption Survey (RECS). By predicting how households are likely to consume energy, homeowners, policy makers, and other stakeholders have access to valuable data that enables reductions in energy consumption in the residential sector. This model can be used to select homes that may be ripe for energy reductions and to predict the appliances that are the basis of these potential reductions. This work suggests that most homes in the U.S. have about eight appliances that are responsible for about 80% of the electricity consumption in that home. Characteristics such as census region, floor space, income, and total electricity consumption affect which appliances are likely to be in a home, however the number of appliances is generally around 8. Generally it takes around 4 appliances to reach the 50% threshold and 12 appliances to reach 90% of electricity

  1. Analyzing Residential End-Use Energy Consumption Data to Inform Residential Consumer Decisions and Enable Energy Efficiency Improvements

    NASA Astrophysics Data System (ADS)

    Carlson, Derrick R.

    While renewable energy is in the process of maturing, energy efficiency improvements may provide an opportunity to reduce energy consumption and consequent greenhouse gas emissions to bridge the gap between current emissions and the reductions necessary to prevent serious effects of climate change and will continue to be an integral part of greenhouse gas emissions policy moving forward. Residential energy is a largely untapped source of energy reductions as consumers, who wish to reduce energy consumption for monetary, environmental, and other reasons, face barriers. One such barrier is a lack of knowledge or understanding of how energy is consumed in a home and how to reduce this consumption effectively through behavioral and technological changes. One way to improve understanding of residential energy consumption is through the creation of a model to predict which appliances and electronics will be present and significantly contribute to the electricity consumption of a home on the basis of various characteristics of that home. The basis of this model is publically available survey data from the Residential Energy Consumption Survey (RECS). By predicting how households are likely to consume energy, homeowners, policy makers, and other stakeholders have access to valuable data that enables reductions in energy consumption in the residential sector. This model can be used to select homes that may be ripe for energy reductions and to predict the appliances that are the basis of these potential reductions. This work suggests that most homes in the U.S. have about eight appliances that are responsible for about 80% of the electricity consumption in that home. Characteristics such as census region, floor space, income, and total electricity consumption affect which appliances are likely to be in a home, however the number of appliances is generally around 8. Generally it takes around 4 appliances to reach the 50% threshold and 12 appliances to reach 90% of electricity

  2. Measured commercial load shapes and energy-use intensities and validation of the LBL end-use disaggregation algorithm. Final report

    SciTech Connect

    Akbari, H.; Rainer, L.; Heinemeier, K.; Huang, J.; Franconi, E.

    1993-01-01

    The Southern California Edison Company (SCE) has conducted an extensive metering project in which electricity end use in 53 commercial buildings in Southern California has been measured. The building types monitored include offices, retail stores, groceries, restaurants, and warehouses. One year (June 1989 through May 1990) of the SCE measured hourly end-use data are reviewed in this report. Annual whole-building and end-use energy use intensities (EUIs) and monthly load shapes (LSs) have been calculated for the different building types based on the monitored data. This report compares the monitored buildings` EUIs and LSs to EUIs and LSs determined using whole-building load data and the End-Use Disaggregation Algorithm (EDA). Two sets of EDA determined EUIs and LSs are compared to the monitored data values. The data sets represent: (1) average buildings in the SCE service territory and (2) specific buildings that were monitored.

  3. US energy flow, 1986

    SciTech Connect

    Borg, I.Y.; Briggs, C.K.

    1987-08-18

    Although growth in the gross national product as well as total energy consumption in 1986 remained at 1985 levels, in detail there were notable changes in 1986. Industrial energy use fell to historical lows recorded in 1983 and all years prior to 1968. The drop is related to increases in end-use efficiencies and to changes in the make-up of the US industrial sector. Imports of goods and services increased as well as crude oil. The consumption of fuels for transportation increased for the third year by an amount approximately equal to the decline in industrial usage. Crude oil imports compensated for a slump in domestic oil production prompted by a downswing in worldwide oil prices. In contrast to the previous decade when the countries in the Middle East and Africa were the most important sources of imported oil and refinery products, in 1986 the three principal sources were Canada, Venezuela and Mexico. Petroleum products comprised a larger share of total oil imports from principal suppliers. Transmitted electricity increased slightly in the 1986 which was made possible by new nuclear capacity that came on line during the year. Cogeneration of electricity and process steam by industrial complexes continued to grow in part because of depressed domestic and Canadian natural gas prices and the favorable rates paid by the utilities for power that are assured by the Public Utilities Regulatory Act of 1978. Alternate sources of fuel for power production (geothermal, wind, solar, etc.) remained at 1985 levels and thus made only a small contribution to the total. The 1986 energy flow - supply and demand - is shown in graphical form using Department of Energy data.

  4. Integrated estimation of commercial sector end-use load shapes and energy use intensities in the PG&E service area

    SciTech Connect

    Akbari, H.; Eto, J.; Konopacki, S.; Afzal, A.; Heinemeier, K.; Rainer, L.

    1993-12-01

    This project represents a unique research effort to address the commercial sector end-use energy forecasting data needs of the Pacific Gas and Electric Company (PG&E) and the California Energy Commission (CEC). The object of the project was to develop an updated set of commercial sector end-use energy use intensity (EUI) data that has been fully reconciled with measured data. The research was conducted in two stages. First, we developed reconciled electricity end-use EUIs and load shapes for each of the 11 building types in the inland and coastal regions of the PG&E service territory using information collected in 1986. Second, we developed procedures to translate these results into a consistent set of commercial sector forecasting model inputs recognizing the separate modeling conventions used by PG&E and CEC. EUIs have been developed for: II commercial building types; up to 10 end uses; up to 3 fuel types; 2 and 5 subservice territory forecasting regions (as specified by the PG&E and CEC forecasting models, respectively); and up to 2 distinct vintages corresponding to the period prior to and immediately following the adoption of the first generation of California building and equipment standards. For the electricity end uses, 36 sets of daily load shapes have been developed representing average weekday, average weekend, and peak weekday electricity use for each month of the year by building type for both the inland and coastal climate zones.

  5. Energy/economic model analysis. Macroeconomic impacts of research and development in gas supply and end use technologies

    NASA Astrophysics Data System (ADS)

    Goettle, R. J., IV; Hudson, E. A.

    1980-06-01

    The Gas Research Institute (GRI) needs to consider the economic impact of the various technologies whose research and development is supported by GRI funding. Three energy-economic models are useful for such a technology assessment. These models are: Energy Economic Modeling System, Energy Policy Model, and Time Stepped Energy System Optimization/Long Term Inter-Industry Transaction Model. These three models were used to help in the economic impact evaluation of various GRI research and development programs.

  6. End-use taxes: Current EIA practices

    SciTech Connect

    Not Available

    1994-08-17

    There are inconsistencies in the EIA published end-use price data with respect to Federal, state, and local government sales and excise taxes; some publications include end-use taxes and others do not. The reason for including these taxes in end-use energy prices is to provide consistent and accurate information on the total cost of energy purchased by the final consumer. Preliminary estimates are made of the effect on prices (bias) reported in SEPER (State Energy Price and Expenditure Report) resulting from the inconsistent treatment of taxes. EIA has undertaken several actions to enhance the reporting of end-use energy prices.

  7. Energy balances in the production and end use of alcohols derived from biomass. A fuels-specific comparative analysis of alternate ethanol production cycles

    SciTech Connect

    Not Available

    1980-10-01

    Considerable public interest and debate have been focused on the so-called energy balance issue involved in the conversion of biomass materials into ethanol for fuel use. This report addresses questions of net gains in premium fuels that can be derived from the production and use of ethanol from biomass, and shows that for the US alcohol fuel program, energy balance need not be a concern. Three categories of fuel gain are discussed in the report: (1) Net petroleum gain; (2) Net premium fuel gain (petroleum and natural gas); and (3) Net energy gain (for all fuels). In this study the investment of energy (in the form of premium fuels) in alcohol production includes all investment from cultivating, harvesting, or gathering the feedstock and raw materials, through conversion of the feedstock to alcohol, to the delivery to the end-user. To determine the fuel gains in ethanol production, six cases, encompassing three feedstocks, five process fuels, and three process variations, have been examined. For each case, two end-uses (automotive fuel use and replacement of petrochemical feedstocks) were scrutinized. The end-uses were further divided into three variations in fuel economy and two different routes for production of ethanol from petrochemicals. Energy requirements calculated for the six process cycles accounted for fuels used directly and indirectly in all stages of alcohol production, from agriculture through distribution of product to the end-user. Energy credits were computed for byproducts according to the most appropriate current use.

  8. Description of Electric Energy Use in Commercial Buildings in the Pacific Northwest: 1992 Supplement. End-use Load and Consumer Assessment Program (ELCAP).

    SciTech Connect

    Taylor, Z. Todd

    1992-07-01

    In December, 1989 Bonneville published Description of Electric Energy Use in Commercial Buildings in the Pacific Northwest, a summary report on the data collected from commercial buildings metered under the End-Use Load and Consumer Assessment Program (ELCAP), for the period 1986 through 1988. Average monthly and annual electric end-use intensities (EUIs, kWh/ft{sup 2}) and average load shapes were presented for nine building types and seven or eight end uses, as well as building totals. This document is a supplement to that report. An additional two and one-half years` data (October 1988 through June 1991) have been collected since the original report, resulting in increased numbers of buildings available for analysis. Additionally, some analytical techniques used in the previous report have been improved and some minor bugs corrected. This supplement differs from the original in the following ways: increased sample sizes; improved analytical techniques; corrected aggregation techniques; eliminated building types; eliminated split plots; included Btu/square foot.

  9. The National Fuel End-Use Efficiency Field Test: Energy Savings and Performance of an Improved Energy Conservation Measure Selection Technique

    SciTech Connect

    Ternes, M.P.

    1991-01-01

    The performance of an advanced residential energy conservation measure (ECM) selection technique was tested in Buffalo, New York, to verify the energy savings and program improvements achieved from use of the technique in conservation programs and provide input into determining whether utility investments in residential gas end-use conservation are cost effective. The technique analyzes a house to identify all ECMs that are cost effective in the building envelope, space-heating system, and water-heating system. The benefit-to-cost ratio (BCR) for each ECM is determined and cost-effective ECMs (BCR > 1.0) are selected once interactions between ECMs are taken into account. Eighty-nine houses with the following characteristics were monitored for the duration of the field test: occupants were low-income, houses were single-family detached houses but not mobile homes, and primary space- and water-heating systems were gas-fired. Forty-five houses received a mix of ECMs as selected by the measure selection technique (audit houses) and 44 served as a control group. Pre-weatherization data were collected from January to April 1988 and post-weatherization data were collected from December 1988 to April 1989. Space- and waterheating gas consumption and indoor temperature were monitored weekly during the two winters. A house energy consumption model and regression analysis were employed to normalize the space-heating energy savings to average outdoor temperature conditions and a 68 F indoor temperature. Space and water-heating energy savings for the audit houses were adjusted by the savings for the control houses. The average savings of 257 therms/year for the audit houses was 17% of the average pre-weatherization house gas consumption and 78% of that predicted. Average space-heating energy savings was 252 therms/year (25% of pre-weatherization space-heating energy consumption and 85% of the predicted value) and average water-heating savings was 5 therms/year (2% of pre

  10. The Flow of Energy

    NASA Astrophysics Data System (ADS)

    Znidarsic, F.; Robertson, G. A.

    In this paper, the flow of energy in materials is presented as mechanical waves with a distinct velocity or speed of transition. This speed of transition came about through the observations of cold fusion experiments, i.e., Low Energy Nuclear Reactions (LENR) and superconductor gravity experiments, both assumed speculative by mainstream science. In consideration of superconductor junctions, the LENR experiments have a similar speed of transition, which seems to imply that the reactions in the LENR experiment are discrete quantized reactions (energy - burst vs. continuous). Here an attempt is made to quantify this new condition as it applies to electrons; toward the progression of quantized energy flows (discrete energy burst) as a new source of clean energy and force mechanisms (i.e, propulsion).

  11. California energy flow in 1989

    NASA Astrophysics Data System (ADS)

    Borg, I. Y.; Briggs, C. K.

    1991-02-01

    California's energy use showed a modest increase (2.2 percent) in 1989 over 1988 which was in keeping with the steady increase in population that the state has experienced annually during the decade. All end-use sectors (residential, commercial, industrial, transportation, etc.) contributed to the growth. The larger demand was met by increased imports of all major fuels. Only electrical imports remained close to 1988 levels, in part due to increased output from Diablo Canyon nuclear plant whose performance exceeded expectations. California's per capita energy consumption has traditionally been below the national average due to the relatively benign climate associated with its centers of population. The largest single use for energy in the state was for transportation, which overtook industrial usage in the 60's. Use of highway fuels continued to grow and reached all time highs in 1989. Highway congestion, a major problem and concern in the state, is anticipated to grow as the number of licensed drivers increases; in 1989 the increase was 3.4 percent. Output from the The Geysers Geothermal fields, the largest in the world, continued to falter as the steam output fell. Nonetheless new resources at the Coso Geothermal Resource Area and at the Wendel Geothermal field came on line during the year, and other geothermal areas were under active development. Novel sources of renewable energy (solar, wind, etc.) grew; however, collectively they made only a small contribution to the overall energy supply. Cogenerated electricity sold to the utilities by small power producers inexplicably fell in 1989 although estimates of the total capacity available rose. Energy flow diagrams illustrate energy sources and energy consumption.

  12. California energy flow in 1992

    SciTech Connect

    Borg, I.Y.; Briggs, C.K.

    1994-04-01

    For the past 16 years energy flow diagrams for the State of California have been prepared from available data by members of the Lawrence Livermore National Laboratory. They have proven to be useful tools in graphically expressing energy supply and use in the State as well as illustrating the difference between particular years and between the State and the US as a whole. As far as is possible, similar data sources have been used to prepare the diagrams from year to year and identical assumptions{sup la-le} concerning conversion efficiencies have been made in order to minimize inconsistencies in the data and analyses. Sources of data used in this report are given in Appendix B and C; unavoidably the sources used over the 1976--1993 period have varied as some data bases are no longer available. In addition, we continue to see differences in specific data reported by different agencies for a given year. In particular, reported data on supply and usage in industrial/commercial/residential end-use categories have shown variability amongst the data gathering agencies, which bars detailed comparisons from year to year. Nonetheless, taken overall, valid generalizations can be made concerning gross trends and changes.

  13. Molecular vibrational energy flow

    NASA Astrophysics Data System (ADS)

    Gruebele, M.; Bigwood, R.

    This article reviews some recent work in molecular vibrational energy flow (IVR), with emphasis on our own computational and experimental studies. We consider the problem in various representations, and use these to develop a family of simple models which combine specific molecular properties (e.g. size, vibrational frequencies) with statistical properties of the potential energy surface and wavefunctions. This marriage of molecular detail and statistical simplification captures trends of IVR mechanisms and survival probabilities beyond the abilities of purely statistical models or the computational limitations of full ab initio approaches. Of particular interest is IVR in the intermediate time regime, where heavy-atom skeletal modes take over the IVR process from hydrogenic motions even upon X H bond excitation. Experiments and calculations on prototype heavy-atom systems show that intermediate time IVR differs in many aspects from the early stages of hydrogenic mode IVR. As a result, IVR can be coherently frozen, with potential applications to selective chemistry.

  14. Technical documentation for the Nonresidential-Buildings Energy-Consumption Survey: 1979-1980, building characteristics, energy end use and fuel oil tank data, public use data tapes. Users' guide

    SciTech Connect

    Not Available

    1982-02-01

    This document provides basic information and technical specifications necessary for using the machine-readable magnetic tapes containing the Building Characteristics, Energy End Use and Fuel Oil Tank data from the 1979-1980 Nonresidential Buildings Energy Consumption Survey (NBECS). Included in this document are a brief overview of the NBECS, technical specifications for reading the tapes and descriptions of the contents of each of the files contained on the tape. The remaining sections are devoted to technical topics of special interest to users of the data. Appended to this document are copies of the questionnaire used in the survey, a listing of the contents of the SPSS labels file, COBOL file description and TPL codebook. The results of the NBECS have been reported in a series of publications which are available to the public. A list of the reports currently available is included here as Appendix H.

  15. Biomass Resource Allocation among Competing End Uses

    SciTech Connect

    Newes, E.; Bush, B.; Inman, D.; Lin, Y.; Mai, T.; Martinez, A.; Mulcahy, D.; Short, W.; Simpkins, T.; Uriarte, C.; Peck, C.

    2012-05-01

    The Biomass Scenario Model (BSM) is a system dynamics model developed by the U.S. Department of Energy as a tool to better understand the interaction of complex policies and their potential effects on the biofuels industry in the United States. However, it does not currently have the capability to account for allocation of biomass resources among the various end uses, which limits its utilization in analysis of policies that target biomass uses outside the biofuels industry. This report provides a more holistic understanding of the dynamics surrounding the allocation of biomass among uses that include traditional use, wood pellet exports, bio-based products and bioproducts, biopower, and biofuels by (1) highlighting the methods used in existing models' treatments of competition for biomass resources; (2) identifying coverage and gaps in industry data regarding the competing end uses; and (3) exploring options for developing models of biomass allocation that could be integrated with the BSM to actively exchange and incorporate relevant information.

  16. California energy flow in 1991

    SciTech Connect

    Borg, I.Y.; Briggs, C.K.

    1993-04-01

    Energy consumption in California fell in 1991 for the first time in five years. The State`s economy was especially hard hit by a continuing national recession. The construction industry for the second year experienced a dramatic downturn. Energy use in the industrial sector showed a modest increase, but consumption in other end-use categories declined. The decrease in energy used in transportation can be traced to a substantial fall in the sales of both highway diesel fuels and vessel bunkering fuels at California ports, the latter reflecting a mid-year increase in taxes. Gasoline sales by contrast increased as did the number of miles traveled and the number of automobiles in the State. Production in California`s oil and gas fields was at 1990 levels thus arresting a steady decline in output. Due to enlarged steam flooding operations, production at several fields reached record levels. Also countering the decline in many of California fields was new production from the Port Arguello offshore field. California natural gas production, despite a modest 1991 increase, will not fill the use within the State. Petroleum comprised more than half of the State`s energy supply principally for transportation. Natural gas use showed a small increase. Oil products play virtually no role in electrical production. The largest single source of electricity to the State is imports from the Pacific Northwest and from coal-fired plants in the Southwest. Combined contributions to transmitted electricity from renewable and alternate sources declined as hydropower was constrained by a prolonged drought and as geothermal power from the largest and oldest field at The Geysers fell. Windpower grew slightly; however solar power remained at 1990 levels and made no substantial contribution to total power generation.

  17. California energy flow in 1994

    SciTech Connect

    Borg, I.Y.; Mui, N.

    1996-09-01

    California energy consumption increased in 1994 in keeping with a recovery from the previous mild recession years. Although unemployment remained above the national average, other indicators pointed to improved economic health. Increased energy use was registered principally in the residential/commercial and transportation end-use sectors. A cooler-than-usual winter and spring was reflected in increased consumption of natural gas, the principal space-heating fuel in the state. Because of low water levels behind state dams, utilities turned to natural gas for electrical generation and to increased imports from out-of- state sources to meet demand. Other factors, such as smaller output from geothermal, biomass, and cogenerators, contributed to the need for the large increase in electrical supply from these two sources. Nonetheless, petroleum dominated the supply side of the energy equation of the state in which transportation requirements comprise more than one-third of total energy demand. About half of the oil consumed derived from California production. Onshore production has been in slow decline; however, in 1994 the decrease was compensated for by increases from federal offshore fields. Until 1994 production had been limited by regulatory restrictions relating to the movement of the crude oil to onshore refineries. State natural gas production remained at 1993 levels. The increased demand was met by larger imports from Canada through the recent expansion of Pacific Transmission Company`s 804 mile pipeline. Deregulation of the state`s utilities moved ahead in 1994 when the California Public Utilities Commission issued its proposal on how to restructure the industry. Public hearings were conducted in which the chief issues were recovery of the utilities` capital investments, conflicts with the Public Utilities Policies Act, management of power transactions between new suppliers and former utility customers, and preservation of energy conservation programs

  18. Magnetic energy flow in the solar wind.

    NASA Technical Reports Server (NTRS)

    Modisette, J. L.

    1972-01-01

    Discussion of the effect of rotation (tangential flow) of the solar wind on the conclusions of Whang (1971) suggesting an increase in the solar wind velocity due to the conversion of magnetic energy to kinetic energy. It is shown that the effect of the rotation of the sun on the magnetic energy flow results in most of the magnetic energy being transported by magnetic shear stress near the sun.

  19. End-Use Efficiency to Lower Carbon Emissions

    SciTech Connect

    Marnay, Chris; Osborn, Julie; Webber, Carrie

    2001-03-01

    Compelling evidence demonstrating the warming trend in global temperatures and the mechanism behind it, namely the anthropogenic emissions of carbon dioxide and other greenhouse gases (GHG), has spurred an international effort to reduce emissions of these gases. Despite improving efficiency of the U.S. economy in terms of energy cost per dollar of GDP since the signing of the Kyoto Protocol, energy consumption and carbon emissions are continuing to rise as the economy expands. This growing gap further emphasizes the importance of improving energy use efficiency as a component in the U.S. climate change mitigation program. The end-use efficiency research activities at Berkeley Lab incorporate residential, commercial, industrial, and transportation sectors. This paper focuses on two successful U.S. programs that address end-use efficiency in residential and commercial demand: energy efficient performance standards established by the Department of Energy (DOE) and the Environmental Protection Agency's (EPA's) ENERGY STAR(registered trademark) program.

  20. Survey-guided load research: An end-use analysis methodology test

    SciTech Connect

    Warwick, W.M.

    1993-08-01

    Energy use by end-use equipment is a function of the rated capacity of the equipment, frequency of use, and duration of each use. Many end used include multiple states, each with a different capacity, frequency, and duration. Some equipment provides benefits that are related to other uses, resulting in an indirect linkage between the primary energy-using equipment and the end use. Water heaters are one example. End-use metering of energy-using equipment provides the most accurate measure of energy use. Nevertheless, this energy-use ``signal`` is buried in background ``noise`` due to variations in the capacity, frequency, and duration of each end use and end user. Reliable estimates of energy use depend on a variety of methods to increase the ``signal-to-noise`` ratio (i.e., reduce the variance). Research of the energy consumption of household end-uses contains some inherent sampling problems: intrusiveness, cost, extensive data generated, analyses are time and computationally intensive. The goal of the methodology test described in this paper was to address these problems through a method that focused end-use analyses on a limited set of issues and data for program evaluation purposes. The approach tested used a detailed survey of end-use metered subjects to identify the pattern of end-use behavior as an alternative to estimating the frequency and duration of each use from the end-use data itself.

  1. Energy storage: Redox flow batteries go organic

    NASA Astrophysics Data System (ADS)

    Wang, Wei; Sprenkle, Vince

    2016-03-01

    The use of renewable resources as providers to the electrical grid is hampered by the intermittent and irregular nature in which they generate energy. Electrical energy storage technology could provide a solution and now, by using an iterative design process, a promising anolyte for use in redox flow batteries has been developed.

  2. Energy flows, metabolism and translation.

    PubMed

    Pascal, Robert; Boiteau, Laurent

    2011-10-27

    Thermodynamics provides an essential approach to understanding how living organisms survive in an organized state despite the second law. Exchanges with the environment constantly produce large amounts of entropy compensating for their own organized state. In addition to this constraint on self-organization, the free energy delivered to the system, in terms of potential, is essential to understand how a complex chemistry based on carbon has emerged. Accordingly, the amount of free energy brought about through discrete events must reach the strength needed to induce chemical changes in which covalent bonds are reorganized. The consequence of this constraint was scrutinized in relation to both the development of a carbon metabolism and that of translation. Amino acyl adenylates involved as aminoacylation intermediates of the latter process reach one of the higher free energy levels found in biochemistry, which may be informative on the range in which energy was exchanged in essential early biochemical processes. The consistency of this range with the amount of energy needed to weaken covalent bonds involving carbon may not be accidental but the consequence of the above mentioned thermodynamic constraints. This could be useful in building scenarios for the emergence and early development of translation.

  3. Energy flows, metabolism and translation

    PubMed Central

    Pascal, Robert; Boiteau, Laurent

    2011-01-01

    Thermodynamics provides an essential approach to understanding how living organisms survive in an organized state despite the second law. Exchanges with the environment constantly produce large amounts of entropy compensating for their own organized state. In addition to this constraint on self-organization, the free energy delivered to the system, in terms of potential, is essential to understand how a complex chemistry based on carbon has emerged. Accordingly, the amount of free energy brought about through discrete events must reach the strength needed to induce chemical changes in which covalent bonds are reorganized. The consequence of this constraint was scrutinized in relation to both the development of a carbon metabolism and that of translation. Amino acyl adenylates involved as aminoacylation intermediates of the latter process reach one of the higher free energy levels found in biochemistry, which may be informative on the range in which energy was exchanged in essential early biochemical processes. The consistency of this range with the amount of energy needed to weaken covalent bonds involving carbon may not be accidental but the consequence of the abovementioned thermodynamic constraints. This could be useful in building scenarios for the emergence and early development of translation. PMID:21930587

  4. Field Flows of Dark Energy

    SciTech Connect

    Cahn, Robert N.; de Putter, Roland; Linder, Eric V.

    2008-07-08

    Scalar field dark energy evolving from a long radiation- or matter-dominated epoch has characteristic dynamics. While slow-roll approximations are invalid, a well defined field expansion captures the key aspects of the dark energy evolution during much of the matter-dominated epoch. Since this behavior is determined, it is not faithfully represented if priors for dynamical quantities are chosen at random. We demonstrate these features for both thawing and freezing fields, and for some modified gravity models, and unify several special cases in the literature.

  5. California energy flow in 1993

    SciTech Connect

    Borg, I.Y.; Briggs, C.K.

    1995-04-01

    Energy consumption in the state of California decreased about 3% in 1993 reflecting continuation of the recession that was manifest in a moribund construction industry and a high state unemployment that ran counter to national recovery trends. Residential/commercial use decreased slightly reflecting a mild winter in the populous southern portion of the state, a decrease that was offset to some extent by an increase in the state population. Industrial consumption of purchased energy declined substantially as did production of self-generated electricity for in-house use. Consumption in the transportation sector decreased slightly. The amount of power transmitted by the utilities was at 1992 levels; however a smaller proportion was produced by the utilities themselves. Generation of electricity by nonutilities, primarily cogenerators and small power producers, was the largest of any state in the US. The growth in the number of private power producers combined with increased amounts of electricity sold to the public utilities set the stage for the sweeping proposals before the California Public Utility Commission to permit direct sales from the nonutilities to retail customers. California production of both oil and natural gas declined; however, to meet demand only the imports of natural gas increased. A break in the decade-long drought during the 1992--1993 season resulted in a substantial increase in the amount of hydroelectricity generated during the year. Geothermal energy`s contribution increased substantially because of the development of new resources by small power producers. Decline in steam production continued at The Geysers, the state`s largest field, principally owned and managed by a public utility. Increases in windpower constituted 1--1/2% of the total electric supply--up slightly from 1992. Several solar photo voltaic demonstration plants were in operation, but their contribution remained small.

  6. High energy density redox flow device

    SciTech Connect

    Chiang, Yet-Ming; Carter, W. Craig; Ho, Bryan Y; Duduta, Mihai; Limthongkul, Pimpa

    2014-05-13

    Redox flow devices are described in which at least one of the positive electrode or negative electrode-active materials is a semi-solid or is a condensed ion-storing electroactive material, and in which at least one of the electrode-active materials is transported to and from an assembly at which the electrochemical reaction occurs, producing electrical energy. The electronic conductivity of the semi-solid is increased by the addition of conductive particles to suspensions and/or via the surface modification of the solid in semi-solids (e.g., by coating the solid with a more electron conductive coating material to increase the power of the device). High energy density and high power redox flow devices are disclosed. The redox flow devices described herein can also include one or more inventive design features. In addition, inventive chemistries for use in redox flow devices are also described.

  7. Mass and energy flow in prominences

    NASA Technical Reports Server (NTRS)

    Poland, Arthur I.

    1990-01-01

    Mass and energy flow in quiescent prominences is considered based on the hypothesis that active region prominences have a different structure and thus different mass and energy flow characteristics. Several important physical parameters have been plotted using the computational model, representing the evolutionary process after the prominence formation. The temperature, velocity, conductive flux, and enthalpy flux are plotted against distance from the highest point in the loop to the coolest part of the prominence. It is shown that the maximum velocity is only about 5 km/s. The model calculations indicate that the transition region of prominences is dominated by complex processes. It is necessary to take into account mass flow at temperatures below 200,000 K, and both mass flow and optical depth effects in hydrogen at temperatures below 30,000 K. Both of these effects lead to a less steep temperature gradient through the prominence corona interface than can be obtained from the conduction alone.

  8. Metallurgical technologies, energy conversion, and magnetohydrodynamic flows

    NASA Astrophysics Data System (ADS)

    Branover, Herman; Unger, Yeshajahu

    The present volume discusses metallurgical applications of MHD, R&D on MHD devices employing liquid working medium for process applications, electromagnetic (EM) modulation of molten metal flow, EM pump performance of superconducting MHD devices, induction EM alkali-metal pumps, a physical model for EM-driven flow in channel-induction furnaces, grain refinement in Al alloys via EM vibrational method, dendrite growth of solidifying metal in dc magnetic field, MHD for mass and heat transfer in single-crystal melt growth, inverse EM shaping, and liquid-metal MHD development in Israel. Also discussed are the embrittlement of steel by lead, an open cycle MHD disk generator, the acceleration of gas-liquid piston flows for molten-metal MHD generators, MHD flow around a cylinder, new MHD drag coefficients, liquid-metal MHD two-phase flow, and two-phase liquid gas mixers for MHD energy conversion. (No individual items are abstracted in this volume)

  9. California energy flow in 1993

    NASA Astrophysics Data System (ADS)

    Borg, I. Y.; Briggs, C. K.

    1995-04-01

    Energy consumption in the state of California decreased about 3% in 1993 reflecting continuation of the recession that was manifest in a moribund construction industry and a high state unemployment that ran counter to national recovery trends. Residential/commercial use decreased slightly reflecting a mild winter in the populous southern portion of the state, a decrease that was offset to some extent by an increase in the state population. Industrial consumption of purchased energy declined substantially as did production of self-generated electricity for in-house use. Consumption in the transportation sector decreased slightly. The amount of power transmitted by the utilities was at 1992 levels; however a smaller proportion was produced by the utilities themselves. Generation of electricity by nonutilities, primarily cogenerators and small power producers, was the largest of any state in the US. The growth in the number of private power producers combined with increased amounts of electricity sold to the public utilities set the stage for the sweeping proposals before the California Public Utility Commission to permit direct sales from the nonutilities to retail customers. California production of both oil and natural gas declined; however, to meet demand only the imports of natural gas increased. A break in the decade-long drought during the 1992-1993 season resulted in a substantial increase in the amount of hydroelectricity generated during the year. Geothermal energy's contribution increased substantially because of the development of new resources by small power producers. Decline in steam production continued at The Geysers, the state's largest field, principally owned and managed by a public utility. Increases in windpower constituted 1-1/2% of the total electric supply, up slightly from 1992. Several solar photovoltaic demonstration plants were in operation, but their contribution remained small.

  10. Snowmass 2001: Jet energy flow project

    SciTech Connect

    C. F. Berger et al.

    2002-12-05

    Conventional cone jet algorithms arose from heuristic considerations of LO hard scattering coupled to independent showering. These algorithms implicitly assume that the final states of individual events can be mapped onto a unique set of jets that are in turn associated with a unique set of underlying hard scattering partons. Thus each final state hadron is assigned to a unique underlying parton. The Jet Energy Flow (JEF) analysis described here does not make such assumptions. The final states of individual events are instead described in terms of flow distributions of hadronic energy. Quantities of physical interest are constructed from the energy flow distribution summed over all events. The resulting analysis is less sensitive to higher order perturbative corrections and the impact of showering and hadronization than the standard cone algorithms.

  11. Dark energy domination in the Virgocentric flow

    NASA Astrophysics Data System (ADS)

    Chernin, A. D.; Karachentsev, I. D.; Nasonova, O. G.; Teerikorpi, P.; Valtonen, M. J.; Dolgachev, V. P.; Domozhilova, L. M.; Byrd, G. G.

    2010-09-01

    Context. The standard ΛCDM cosmological model implies that all celestial bodies are embedded in a perfectly uniform dark energy background, represented by Einstein's cosmological constant, and experience its repulsive antigravity action. Aims: Can dark energy have strong dynamical effects on small cosmic scales as well as globally? Continuing our efforts to clarify this question, we now focus on the Virgo Cluster and the flow of expansion around it. Methods: We interpret the Hubble diagram from a new database of velocities and distances of galaxies in the cluster and its environment, using a nonlinear analytical model, which incorporates the antigravity force in terms of Newtonian mechanics. The key parameter is the zero-gravity radius, the distance at which gravity and antigravity are in balance. Results: 1. The interplay between the gravity of the cluster and the antigravity of the dark energy background determines the kinematical structure of the system and controls its evolution. 2. The gravity dominates the quasi-stationary bound cluster, while the antigravity controls the Virgocentric flow, bringing order and regularity to the flow, which reaches linearity and the global Hubble rate at distances ⪆15 Mpc. 3. The cluster and the flow form a system similar to the Local Group and its outflow. In the velocity-distance diagram, the cluster-flow structure reproduces the group-flow structure with a scaling factor of about 10; the zero-gravity radius for the cluster system is also 10 times larger. Conclusions: The phase and dynamical similarity of the systems on the scales of 1-30 Mpc suggests that a two-component pattern may be universal for groups and clusters: a quasi-stationary bound central component and an expanding outflow around it, caused by the nonlinear gravity-antigravity interplay with the dark energy dominating in the flow component.

  12. Rare earth elements: end use and recyclability

    USGS Publications Warehouse

    Goonan, Thomas G.

    2011-01-01

    Rare earth elements are used in mature markets (such as catalysts, glassmaking, lighting, and metallurgy), which account for 59 percent of the total worldwide consumption of rare earth elements, and in newer, high-growth markets (such as battery alloys, ceramics, and permanent magnets), which account for 41 percent of the total worldwide consumption of rare earth elements. In mature market segments, lanthanum and cerium constitute about 80 percent of rare earth elements used, and in new market segments, dysprosium, neodymium, and praseodymium account for about 85 percent of rare earth elements used. Regardless of the end use, rare earth elements are not recycled in large quantities, but could be if recycling became mandated or very high prices of rare earth elements made recycling feasible.

  13. U.S. Energy Flow -- 1995

    SciTech Connect

    Miller, H; Mui, N; Pasternak, A

    1997-12-01

    Energy consumption in 1995 increased slightly for the fifth year in a row (from 89 to 91 quadrillion [1015Btu). U.S. economic activity slowed from the fast-paced recovery of 1994, even with the continued low unemployment rates and low inflation rates. The annual increase in U.S. real GDP dropped to 4.6% from 1994's increase of 5.8%. Energy consumption in all major end-use sectors surpassed the record-breaking highs achieved in 1994, with the largest gains (2.5%) occurring in the residential/commercial sector. Crude oil imports decreased for the first time this decade. There was also a decline in domestic oil production. Venezuela replaced Saudi Arabia as the principal supplier of imported oil. Imports of natural gas, mainly from Canada, continued to increase. The demand for natural gas reached a level not seen since the peak levels of the early 1970s and the demand was met by a slight increase in both natural gas production and imports. Electric utilities had the largest percentage increase of n.atural gas consumption, a climb of 7% above 1994 levels. Although coal production decreased, coal exports continued to make a comeback after 3 years of decline. Coal once again become the primary U.S. energy export. Title IV of the Clean Air Act Amendments of 1990 (CAAA90) consists of two phases. Phase I (in effect as of January 1, 1995) set emission restrictions on 110 mostly coal-burning plants in the eastern and midwestem United States. Phase II, planned to begin in the year 2000, places additional emission restrictions on about 1,000 electric plants. As of January 1, 1995, the reformulated gasoline program, also part of the CAAA90, was finally initiated. As a result, this cleaner-burning fuel was made available in areas of the United States that failed to meet the Environmental Protection Agency's (EPA's) ozone standards. In 1995, reformulated gasoline represented around 28% of total gasoline sales in the United States. The last commercial nuclear power plant

  14. End-Use Load and Consumer Assessment Program: Characterizing residential thermal performance from high resolution end-use data

    SciTech Connect

    Miller, N.E.; Pearson, E.W.; Stokes, G.M.; Pratt, R.G.; Williamson, M.A.

    1991-01-01

    The Bonneville Power Administration (Bonneville) began the End-Use Load and Consumer Assessment Program (ELCAP) in 1983. Prior to beginning the ELCAP, there was an abundance of information regarding total power consumption for residential structures in the Pacific Northwest and limited information regarding power consumption by various end uses. The purpose of ELCAP is to collect actual end-use load data from both residential and commercial buildings in the region. This report presents the methodology used in several statistical modeling studies carried out on the ELCAP data between 1986 and 1989. These studies involve the thermal characterization of homes and comparisons of building techniques and conservation measures by residential and commercial consumers within the Bonneville service area of the Pacific Northwest. Each data gathering technique was successful in extracting a specific set of consumer-related energy use information. The analytical techniques used in these studies are compiled in this methodology report and are to be used in conjunction with Volume 2 -- Analysis. This should facilitate ease of reference use during future analyses. It is anticipated that the data gathered on participating consumers could potentially be used to aid in decisions regarding the management of the Northwest's electrical energy resources. 7 refs., 6 figs., 2 tabs.

  15. Piezoelectric energy harvesting in internal fluid flow.

    PubMed

    Lee, Hyeong Jae; Sherrit, Stewart; Tosi, Luis Phillipe; Walkemeyer, Phillip; Colonius, Tim

    2015-10-14

    We consider piezoelectric flow energy harvesting in an internal flow environment with the ultimate goal powering systems such as sensors in deep oil well applications. Fluid motion is coupled to structural vibration via a cantilever beam placed in a converging-diverging flow channel. Two designs were considered for the electromechanical coupling: first; the cantilever itself is a piezoelectric bimorph; second; the cantilever is mounted on a pair of flextensional actuators. We experimentally investigated varying the geometry of the flow passage and the flow rate. Experimental results revealed that the power generated from both designs was similar; producing as much as 20 mW at a flow rate of 20 L/min. The bimorph designs were prone to failure at the extremes of flow rates tested. Finite element analysis (FEA) showed fatigue failure was imminent due to stress concentrations near the bimorph's clamped region; and that robustness could be improved with a stepped-joint mounting design. A similar FEA model showed the flextensional-based harvester had a resonant frequency of around 375 Hz and an electromechanical coupling of 0.23 between the cantilever and flextensional actuators in a vacuum. These values; along with the power levels demonstrated; are significant steps toward building a system design that can eventually deliver power in the Watts range to devices down within a well.

  16. Piezoelectric energy harvesting in internal fluid flow.

    PubMed

    Lee, Hyeong Jae; Sherrit, Stewart; Tosi, Luis Phillipe; Walkemeyer, Phillip; Colonius, Tim

    2015-01-01

    We consider piezoelectric flow energy harvesting in an internal flow environment with the ultimate goal powering systems such as sensors in deep oil well applications. Fluid motion is coupled to structural vibration via a cantilever beam placed in a converging-diverging flow channel. Two designs were considered for the electromechanical coupling: first; the cantilever itself is a piezoelectric bimorph; second; the cantilever is mounted on a pair of flextensional actuators. We experimentally investigated varying the geometry of the flow passage and the flow rate. Experimental results revealed that the power generated from both designs was similar; producing as much as 20 mW at a flow rate of 20 L/min. The bimorph designs were prone to failure at the extremes of flow rates tested. Finite element analysis (FEA) showed fatigue failure was imminent due to stress concentrations near the bimorph's clamped region; and that robustness could be improved with a stepped-joint mounting design. A similar FEA model showed the flextensional-based harvester had a resonant frequency of around 375 Hz and an electromechanical coupling of 0.23 between the cantilever and flextensional actuators in a vacuum. These values; along with the power levels demonstrated; are significant steps toward building a system design that can eventually deliver power in the Watts range to devices down within a well. PMID:26473879

  17. Piezoelectric Energy Harvesting in Internal Fluid Flow

    PubMed Central

    Lee, Hyeong Jae; Sherrit, Stewart; Tosi, Luis Phillipe; Walkemeyer, Phillip; Colonius, Tim

    2015-01-01

    We consider piezoelectric flow energy harvesting in an internal flow environment with the ultimate goal powering systems such as sensors in deep oil well applications. Fluid motion is coupled to structural vibration via a cantilever beam placed in a converging-diverging flow channel. Two designs were considered for the electromechanical coupling: first; the cantilever itself is a piezoelectric bimorph; second; the cantilever is mounted on a pair of flextensional actuators. We experimentally investigated varying the geometry of the flow passage and the flow rate. Experimental results revealed that the power generated from both designs was similar; producing as much as 20 mW at a flow rate of 20 L/min. The bimorph designs were prone to failure at the extremes of flow rates tested. Finite element analysis (FEA) showed fatigue failure was imminent due to stress concentrations near the bimorph’s clamped region; and that robustness could be improved with a stepped-joint mounting design. A similar FEA model showed the flextensional-based harvester had a resonant frequency of around 375 Hz and an electromechanical coupling of 0.23 between the cantilever and flextensional actuators in a vacuum. These values; along with the power levels demonstrated; are significant steps toward building a system design that can eventually deliver power in the Watts range to devices down within a well. PMID:26473879

  18. Localized flow control with energy deposition

    NASA Astrophysics Data System (ADS)

    Adelgren, Russell Gene

    A series of experiments with energy deposition via laser-induced optical breakdown of air, i.e., a laser spark, have been performed. These experiments have demonstrated the possibility of using a laser spark for supersonic flow control. In the first of these experiments, Rayleigh scattering flow visualization was taken for energy deposition into quiescent air. A time sequence of images showed the post breakdown fluid motion created by the laser spark for different laser energy levels. Blast wave radius and wave speed measurements were made and correlated to five different laser energy deposition levels. Laser energy was deposited upstream of a sphere in Mach 3.45 flow. The energy was deposited one sphere diameter and 0.6 diameters upstream of the front of the sphere. The frontal surface pressure on the sphere was recorded as the laser spark perturbed region interacted with the flow about the sphere. Tests for three different energy levels and two different incident laser beam diameters were completed. It has been demonstrated that the peak surface pressure associated with the Edney IV interaction can be momentarily reduced by 30% by the interaction with the thermal spot created by the laser spark. The effects of laser energy deposition on another shock interaction phenomena were studied. Laser energy deposition was used to modify the shock structure formed by symmetric wedges at Mach 3.45 within the dual solution domain. It was demonstrated experimentally that the Mach reflection could be reduced by 80% momentarily. The numerical simulations show a transition from the stable Mach reflection to a stable regular reflection. Two energy deposition methods (electric arcing and laser energy deposition) were used to force and control compressible mixing layers of axisymmetric jets. The energy deposition forcing methods have been experimentally investigated with the schlieren technique, particle image velocimetry, Mie scattering, and static pressure probe diagnostic

  19. Energy and material flows of megacities

    PubMed Central

    Kennedy, Christopher A.; Stewart, Iain; Facchini, Angelo; Cersosimo, Igor; Mele, Renata; Chen, Bin; Uda, Mariko; Kansal, Arun; Chiu, Anthony; Kim, Kwi-gon; Dubeux, Carolina; Lebre La Rovere, Emilio; Cunha, Bruno; Pincetl, Stephanie; Keirstead, James; Barles, Sabine; Pusaka, Semerdanta; Gunawan, Juniati; Adegbile, Michael; Nazariha, Mehrdad; Hoque, Shamsul; Marcotullio, Peter J.; González Otharán, Florencia; Genena, Tarek; Ibrahim, Nadine; Farooqui, Rizwan; Cervantes, Gemma; Sahin, Ahmet Duran

    2015-01-01

    Understanding the drivers of energy and material flows of cities is important for addressing global environmental challenges. Accessing, sharing, and managing energy and material resources is particularly critical for megacities, which face enormous social stresses because of their sheer size and complexity. Here we quantify the energy and material flows through the world’s 27 megacities with populations greater than 10 million people as of 2010. Collectively the resource flows through megacities are largely consistent with scaling laws established in the emerging science of cities. Correlations are established for electricity consumption, heating and industrial fuel use, ground transportation energy use, water consumption, waste generation, and steel production in terms of heating-degree-days, urban form, economic activity, and population growth. The results help identify megacities exhibiting high and low levels of consumption and those making efficient use of resources. The correlation between per capita electricity use and urbanized area per capita is shown to be a consequence of gross building floor area per capita, which is found to increase for lower-density cities. Many of the megacities are growing rapidly in population but are growing even faster in terms of gross domestic product (GDP) and energy use. In the decade from 2001–2011, electricity use and ground transportation fuel use in megacities grew at approximately half the rate of GDP growth. PMID:25918371

  20. Energy and material flows of megacities.

    PubMed

    Kennedy, Christopher A; Stewart, Iain; Facchini, Angelo; Cersosimo, Igor; Mele, Renata; Chen, Bin; Uda, Mariko; Kansal, Arun; Chiu, Anthony; Kim, Kwi-Gon; Dubeux, Carolina; Lebre La Rovere, Emilio; Cunha, Bruno; Pincetl, Stephanie; Keirstead, James; Barles, Sabine; Pusaka, Semerdanta; Gunawan, Juniati; Adegbile, Michael; Nazariha, Mehrdad; Hoque, Shamsul; Marcotullio, Peter J; González Otharán, Florencia; Genena, Tarek; Ibrahim, Nadine; Farooqui, Rizwan; Cervantes, Gemma; Sahin, Ahmet Duran

    2015-05-12

    Understanding the drivers of energy and material flows of cities is important for addressing global environmental challenges. Accessing, sharing, and managing energy and material resources is particularly critical for megacities, which face enormous social stresses because of their sheer size and complexity. Here we quantify the energy and material flows through the world's 27 megacities with populations greater than 10 million people as of 2010. Collectively the resource flows through megacities are largely consistent with scaling laws established in the emerging science of cities. Correlations are established for electricity consumption, heating and industrial fuel use, ground transportation energy use, water consumption, waste generation, and steel production in terms of heating-degree-days, urban form, economic activity, and population growth. The results help identify megacities exhibiting high and low levels of consumption and those making efficient use of resources. The correlation between per capita electricity use and urbanized area per capita is shown to be a consequence of gross building floor area per capita, which is found to increase for lower-density cities. Many of the megacities are growing rapidly in population but are growing even faster in terms of gross domestic product (GDP) and energy use. In the decade from 2001-2011, electricity use and ground transportation fuel use in megacities grew at approximately half the rate of GDP growth. PMID:25918371

  1. Energy and material flows of megacities.

    PubMed

    Kennedy, Christopher A; Stewart, Iain; Facchini, Angelo; Cersosimo, Igor; Mele, Renata; Chen, Bin; Uda, Mariko; Kansal, Arun; Chiu, Anthony; Kim, Kwi-Gon; Dubeux, Carolina; Lebre La Rovere, Emilio; Cunha, Bruno; Pincetl, Stephanie; Keirstead, James; Barles, Sabine; Pusaka, Semerdanta; Gunawan, Juniati; Adegbile, Michael; Nazariha, Mehrdad; Hoque, Shamsul; Marcotullio, Peter J; González Otharán, Florencia; Genena, Tarek; Ibrahim, Nadine; Farooqui, Rizwan; Cervantes, Gemma; Sahin, Ahmet Duran

    2015-05-12

    Understanding the drivers of energy and material flows of cities is important for addressing global environmental challenges. Accessing, sharing, and managing energy and material resources is particularly critical for megacities, which face enormous social stresses because of their sheer size and complexity. Here we quantify the energy and material flows through the world's 27 megacities with populations greater than 10 million people as of 2010. Collectively the resource flows through megacities are largely consistent with scaling laws established in the emerging science of cities. Correlations are established for electricity consumption, heating and industrial fuel use, ground transportation energy use, water consumption, waste generation, and steel production in terms of heating-degree-days, urban form, economic activity, and population growth. The results help identify megacities exhibiting high and low levels of consumption and those making efficient use of resources. The correlation between per capita electricity use and urbanized area per capita is shown to be a consequence of gross building floor area per capita, which is found to increase for lower-density cities. Many of the megacities are growing rapidly in population but are growing even faster in terms of gross domestic product (GDP) and energy use. In the decade from 2001-2011, electricity use and ground transportation fuel use in megacities grew at approximately half the rate of GDP growth.

  2. Observing and modeling Earths energy flows

    SciTech Connect

    Stevens B.; Schwartz S.

    2012-05-11

    This article reviews, from the authors perspective, progress in observing and modeling energy flows in Earth's climate system. Emphasis is placed on the state of understanding of Earth's energy flows and their susceptibility to perturbations, with particular emphasis on the roles of clouds and aerosols. More accurate measurements of the total solar irradiance and the rate of change of ocean enthalpy help constrain individual components of the energy budget at the top of the atmosphere to within {+-}2 W m{sup -2}. The measurements demonstrate that Earth reflects substantially less solar radiation and emits more terrestrial radiation than was believed even a decade ago. Active remote sensing is helping to constrain the surface energy budget, but new estimates of downwelling surface irradiance that benefit from such methods are proving difficult to reconcile with existing precipitation climatologies. Overall, the energy budget at the surface is much more uncertain than at the top of the atmosphere. A decade of high-precision measurements of the energy budget at the top of the atmosphere is providing new opportunities to track Earth's energy flows on timescales ranging from days to years, and at very high spatial resolution. The measurements show that the principal limitation in the estimate of secular trends now lies in the natural variability of the Earth system itself. The forcing-feedback-response framework, which has developed to understand how changes in Earth's energy flows affect surface temperature, is reviewed in light of recent work that shows fast responses (adjustments) of the system are central to the definition of the effective forcing that results from a change in atmospheric composition. In many cases, the adjustment, rather than the characterization of the compositional perturbation (associated, for instance, with changing greenhouse gas concentrations, or aerosol burdens), limits accurate determination of the radiative forcing. Changes in clouds

  3. Whistler Wave Energy Flow in the Plasmasphere

    NASA Astrophysics Data System (ADS)

    Kletzing, Craig; Santolik, Ondrej; Kurth, William; Hospodarsky, George; Christopher, Ivar; Bounds, Scott

    2016-07-01

    The measured wave properties of plasmaspheric hiss are important to constrain models of the generation of hiss as well as its propagation and amplification. For example, the generation mechanism for plasmaspheric hiss has been suggested to come from one of three possible mechanisms: 1) local generation and amplification, 2) whistlers from lightning, and 3) chorus emissions which have refracted into the plasmasphere. The latter two mechanisms are external sources which produce an incoherent hiss signature as the original waves mix in a stochastic manner, propagating in both directions along the background magnetic field. In contrast, local generation of plasmaspheric hiss within the plasmasphere should produce a signature of waves propagating away from the source region. For all three mechanisms scattering of energetic particles into the loss cone transfers some energy from the particles to the waves. By examining the statistical characteristics of the Poynting flux of plasmaspheric hiss, we can determine the properties of wave energy flow in the plasmasphere. We report on the statistics of observations from the Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) Waves instrument on the Van Allen Probes for periods when the spacecraft is inside the plasmasphere. We find that the Poynting flux associated with plasmaspheric hiss has distinct and unexpected radial structure which shows that there can be significant energy flow towards the magnetic equator. We show the properties of this electromagnetic energy flow as a function of position and frequency.

  4. U.S. energy flow -- 1994

    SciTech Connect

    Borg, I.Y.; Briggs, C.K.

    1995-12-01

    Energy consumption in 1994 increased for the fourth year in a row, reaching an all-time high. It was associated with a robust economy, low inflation, and low unemployment rates. Of the populous states, California lagged substantially behind the national recovery. Consumption in all major end-use sectors reached historic highs. Transmission of electrical power by the utilities increased almost 3%. However, this understates the increase of the total amount of electricity used in the nation because the amount of electricity used ``in-house`` by a growing number of self-generators is unrecorded. Imports of both fossil fuels and electricity increased. About half of the total oil consumed was imported, with Saudi Arabia being the principal supplier. Domestic oil production continued to decline; however, the sharp decline in Alaskan production was slowed. The increase in the demand for natural gas was met by both a modest increase in domestic production and imports from Canada, which comprised 10% of supply. The residential/commercial sector is the largest single consumer of natural gas; however, use by electric generators has increased annually for the past decade. The regulated utilities increased their consumption 11% in 1994. The year was noteworthy for the US nuclear power industry. Work was halted on the last nuclear power plant under construction in the country. Because of the retirement of aged and poorly performing nuclear plants and because of improved efficiencies, the capacity factor for the remaining 109 operable plants reached a record 74%.

  5. 15 CFR 744.2 - Restrictions on certain nuclear end-uses.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., as amended, as implemented by the Department of Energy's regulations published in 10 CFR 810. (i... 15 Commerce and Foreign Trade 2 2012-01-01 2012-01-01 false Restrictions on certain nuclear end... POLICY: END-USER AND END-USE BASED § 744.2 Restrictions on certain nuclear end-uses. (a)...

  6. 15 CFR 744.2 - Restrictions on certain nuclear end-uses.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., as amended, as implemented by the Department of Energy's regulations published in 10 CFR 810. (i... 15 Commerce and Foreign Trade 2 2013-01-01 2013-01-01 false Restrictions on certain nuclear end... POLICY: END-USER AND END-USE BASED § 744.2 Restrictions on certain nuclear end-uses. (a)...

  7. 15 CFR 744.2 - Restrictions on certain nuclear end-uses.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., as amended, as implemented by the Department of Energy's regulations published in 10 CFR 810. (i... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Restrictions on certain nuclear end... POLICY: END-USER AND END-USE BASED § 744.2 Restrictions on certain nuclear end-uses. (a)...

  8. 15 CFR 744.2 - Restrictions on certain nuclear end-uses.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., as amended, as implemented by the Department of Energy's regulations published in 10 CFR 810. (i... 15 Commerce and Foreign Trade 2 2014-01-01 2014-01-01 false Restrictions on certain nuclear end... POLICY: END-USER AND END-USE BASED § 744.2 Restrictions on certain nuclear end-uses. (a)...

  9. 15 CFR 744.2 - Restrictions on certain nuclear end-uses.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., as amended, as implemented by the Department of Energy's regulations published in 10 CFR 810. (i... 15 Commerce and Foreign Trade 2 2011-01-01 2011-01-01 false Restrictions on certain nuclear end... POLICY: END-USER AND END-USE BASED § 744.2 Restrictions on certain nuclear end-uses. (a)...

  10. Graphene plasmonic lens for manipulating energy flow

    NASA Astrophysics Data System (ADS)

    Wang, Guoxi; Liu, Xueming; Lu, Hua; Zeng, Chao

    2014-02-01

    Manipulating the energy flow of light is at the heart of modern information and communication technologies. Because photons are uncharged, it is still difficult to effectively control them by electrical means. Here, we propose a graphene plasmonic (GP) lens to efficiently manipulate energy flow by elaborately designing the thickness of the dielectric spacer beneath the graphene sheet. Different from traditional metal-based lenses, the proposed graphene plasmonic lens possesses the advantages of tunability and excellent confinement of surface plasmons. It is found that the proposed lens can be utilized to focus and collimate the GP waves propagating along the graphene sheet. Particularly, the lens is dispersionless over a wide frequency range and the performance of lens can be flexibly tuned by adjusting the bias voltage. As an application of such a lens, the image transfer of two point sources with a separation of λ0/30 is demonstrated.

  11. Graphene plasmonic lens for manipulating energy flow

    PubMed Central

    Wang, Guoxi; Liu, Xueming; Lu, Hua; Zeng, Chao

    2014-01-01

    Manipulating the energy flow of light is at the heart of modern information and communication technologies. Because photons are uncharged, it is still difficult to effectively control them by electrical means. Here, we propose a graphene plasmonic (GP) lens to efficiently manipulate energy flow by elaborately designing the thickness of the dielectric spacer beneath the graphene sheet. Different from traditional metal-based lenses, the proposed graphene plasmonic lens possesses the advantages of tunability and excellent confinement of surface plasmons. It is found that the proposed lens can be utilized to focus and collimate the GP waves propagating along the graphene sheet. Particularly, the lens is dispersionless over a wide frequency range and the performance of lens can be flexibly tuned by adjusting the bias voltage. As an application of such a lens, the image transfer of two point sources with a separation of λ0/30 is demonstrated. PMID:24517981

  12. Flow Energy Piezoelectric Bimorph Nozzle Harvester

    NASA Technical Reports Server (NTRS)

    Sherrit, Stewart; Lee, Hyeong Jae; Kim, Namhyo; Sun, Kai; Corbett, Gary; Walkemeyer, Phillip; Hasenoehrl, Jennifer; Hall, Jeffery L.; Colonius, Tim; Tosi, Luis Phillipe; Arrazola, Alvaro

    2014-01-01

    There is a need for a long-life power generation scheme that could be used downhole in an oil well to produce 1 Watt average power. There are a variety of existing or proposed energy harvesting schemes that could be used in this environment but each of these has its own limitations. The vibrating piezoelectric structure is in principle capable of operating for very long lifetimes (decades) thereby possibly overcoming a principle limitation of existing technology based on rotating turbo-machinery. In order to determine the feasibility of using piezoelectrics to produce suitable flow energy harvesting, we surveyed experimentally a variety of nozzle configurations that could be used to excite a vibrating piezoelectric structure in such a way as to enable conversion of flow energy into useful amounts of electrical power. These included reed structures, spring mass-structures, drag and lift bluff bodies and a variety of nozzles with varying flow profiles. Although not an exhaustive survey we identified a spline nozzle/piezoelectric bimorph system that experimentally produced up to 3.4 mW per bimorph. This paper will discuss these results and present our initial analyses of the device using dimensional analysis and constitutive electromechanical modeling. The analysis suggests that an order-of-magnitude improvement in power generation from the current design is possible.

  13. Energy flow and energy dissipation in a free surface.

    NASA Astrophysics Data System (ADS)

    Goldburg, Walter; Cressman, John

    2005-11-01

    Turbulent flows on a free surface are strongly compressible [1] and do not conserve energy in the absence of viscosity as bulk fluids do. Despite violation of assumptions essential to Kolmogorov's theory of 1941 (K41) [2, 3], surface flows show strong agreement with Kolmogorov scaling, though intermittency is larger there. Steady state turbulence is generated in a tank of water, and the spatially averaged energy flux is measured from the four-fifth's law at each instant of time. Likewise, the energy dissipation rate as measured from velocity gradients is also a random variable in this experiment. The energy flux - dissipation rate cross-correlation is measured to be correlated in incompressible bulk flows, but strongly anti-correlated on the surface. We argue that the reason for this discrepancy between surface and bulk flows is due to compressible effects present on the surface. [1] J. R. Cressman, J. Davoudi, W. I. Goldburg, and J. Schumacher, New Journal of Physics, 6, 53, 2004. [2] U. Frisch. Turbulence: The legacy of A. N. Kolmogorov, Cambridge University Press, Cambridge, 1995. [3] A. N. Kolmogorov, Doklady Akad. Nauk SSSR, 32, 16, 1941.

  14. Energy efficient continuous flow ash lockhopper

    NASA Technical Reports Server (NTRS)

    Collins, Earl R., Jr. (Inventor); Suitor, Jerry W. (Inventor); Dubis, David (Inventor)

    1989-01-01

    The invention relates to an energy efficient continuous flow ash lockhopper, or other lockhopper for reactor product or byproduct. The invention includes an ash hopper at the outlet of a high temperature, high pressure reactor vessel containing heated high pressure gas, a fluidics control chamber having an input port connected to the ash hopper's output port and an output port connected to the input port of a pressure letdown means, and a control fluid supply for regulating the pressure in the control chamber to be equal to or greater than the internal gas pressure of the reactor vessel, whereby the reactor gas is contained while ash is permitted to continuously flow from the ash hopper's output port, impelled by gravity. The main novelty resides in the use of a control chamber to so control pressure under the lockhopper that gases will not exit from the reactor vessel, and to also regulate the ash flow rate. There is also novelty in the design of the ash lockhopper shown in two figures. The novelty there is the use of annular passages of progressively greater diameter, and rotating the center parts on a shaft, with the center part of each slightly offset from adjacent ones to better assure ash flow through the opening.

  15. Energy flow for electric power system deregulation

    NASA Astrophysics Data System (ADS)

    Lin, Chia-Hung

    Over the past few years, the electric power utility industry in North America and other countries has experienced a strong drive towards deregulation. People have considered the necessity of deregulation of electric utilities for higher energy efficiency and energy saving. The vertically integrated monopolistic industry is being transferred into a horizontally integrated competitive structure in some countries. Wheeling charges are a current high priority problem throughout the power industry, for independent power producers, as well as regulators. Nevertheless the present transmission pricing mechanism fails to be adjusted by a customer loading condition. Customer loading is dynamic, but the present wheeling charge method is fixed, not real-time. A real-time wheeling charge method is developed in this dissertation. This dissertation introduces a concept of a power flow network which can be used for the calculation of power contribution factors in a network. The contribution factor is defined as the ratio of the power contributed by a particular source to a line flow or bus load to the total output of the source. Generation, transmission, and distribution companies can employ contribution factors for the calculation of energy cost, wheeling charges, and loss compensation. Based on the concept of contribution factors, a proposed loss allocation method is developed in this dissertation. Besides, counterflow condition will be given a credit in the proposed loss allocation method. A simple 22-bus example was used for evaluating the contribution factors, proposed wheeling charge method, and loss allocation method.

  16. Dark Energy Domination In The Virgocentric Flow

    NASA Astrophysics Data System (ADS)

    Byrd, Gene; Chernin, A. D.; Karachentsev, I. D.; Teerikorpi, P.; Valtonen, M.; Dolgachev, V. P.; Domozhilova, L. M.

    2011-04-01

    Dark energy (DE) was first observationally detected at large Gpc distances. If it is a vacuum energy formulated as Einstein's cosmological constant, Λ, DE should also have dynamical effects at much smaller scales. Previously, we found its effects on much smaller Mpc scales in our Local Group (LG) as well as in other nearby groups. We used new HST observations of member 3D distances from the group centers and Doppler shifts. We find each group's gravity dominates a bound central system of galaxies but DE antigravity results in a radial recession increasing with distance from the group center of the outer members. Here we focus on the much larger (but still cosmologically local) Virgo Cluster and systems around it using new observations of velocities and distances. We propose an analytic model whose key parameter is the zero-gravity radius (ZGR) from the cluster center where gravity and DE antigravity balance. DE brings regularity to the Virgocentric flow. Beyond Virgo's 10 Mpc ZGR, the flow curves to approach a linear global Hubble law at larger distances. The Virgo cluster and its outer flow are similar to the Local Group and its local outflow with a scaling factor of about 10; the ZGR for Virgo is 10 times larger than that of the LG. The similarity of the two systems on the scales of 1 to 30 Mpc suggests that a quasi-stationary bound central component and an expanding outflow applies to a wide range of groups and clusters due to small scale action of DE as well as gravity. Chernin, et al 2009 Astronomy and Astrophysics 507, 1271 http://arxiv.org/abs/1006.0066 http://arxiv.org/abs/1006.0555

  17. Analysis of PG E's residential end-use metered data to improve electricity demand forecasts

    SciTech Connect

    Eto, J.H.; Moezzi, M.M.

    1992-06-01

    It is generally acknowledged that improvements to end-use load shape and peak demand forecasts for electricity are limited primarily by the absence of reliable end-use data. In this report we analyze recent end-use metered data collected by the Pacific Gas and Electric Company from more than 700 residential customers to develop new inputs for the load shape and peak demand electricity forecasting models used by the Pacific Gas and Electric Company and the California Energy Commission. Hourly load shapes are normalized to facilitate separate accounting (by the models) of annual energy use and the distribution of that energy use over the hours of the day. Cooling electricity consumption by central air-conditioning is represented analytically as a function of climate. Limited analysis of annual energy use, including unit energy consumption (UEC), and of the allocation of energy use to seasons and system peak days, is also presented.

  18. Energy flow model for thin plate considering fluid loading with mean flow

    NASA Astrophysics Data System (ADS)

    Han, Ju-Bum; Hong, Suk-Yoon; Song, Jee-Hun

    2012-11-01

    Energy Flow Analysis (EFA) has been developed to predict the vibration energy density of system structures in the high frequency range. This paper develops the energy flow model for the thin plate in contact with mean flow. The pressure generated by mean flow affects energy governing equation and power reflection-transmission coefficients between plates. The fluid pressure is evaluated by using velocity potential and Bernoulli's equation, and energy governing equations are derived by considering the flexural wavenumbers of a plate, which are different along the direction of flexural wave and mean flow. The derived energy governing equation is composed of two kinds of group velocities. To verify the developed energy flow model, various numerical analyses are performed for a simple plate and a coupled plate for several excitation frequencies. The EFA results are compared with the analytical solutions, and correlations between the EFA results and the analytical solutions are verified.

  19. Energy flow in an arctic aquatic ecosystem

    SciTech Connect

    Schell, D.M.

    1993-05-01

    This project has been using natural isotope abundances to trace major pathways of energy flow to consumers in Imnavait Creek and the tundra ecosystem of the R4D watershed with comparative work in the coastal tundra. We are processing samples collected at the R4D intensive site over the past three years and are comparing these data with similar samples collected from the coastal plain. Our approach is to determine if carbon is accumulating in upland and coastal tundra; to determine the role of eroded peat carbon in the aquatic ecosystem; and to determine the distribution of carbon and nitrogen isotopes in the tundra-pond ecosystem to establish the feasibility of using natural differences as tracers.

  20. Energy flow in an arctic aquatic ecosystem

    SciTech Connect

    Schell, D.M.

    1993-01-01

    This project has been using natural isotope abundances to trace major pathways of energy flow to consumers in Imnavait Creek and the tundra ecosystem of the R4D watershed with comparative work in the coastal tundra. We are processing samples collected at the R4D intensive site over the past three years and are comparing these data with similar samples collected from the coastal plain. Our approach is to determine if carbon is accumulating in upland and coastal tundra; to determine the role of eroded peat carbon in the aquatic ecosystem; and to determine the distribution of carbon and nitrogen isotopes in the tundra-pond ecosystem to establish the feasibility of using natural differences as tracers.

  1. Deuterons and flow: At intermediate AGS energies

    SciTech Connect

    Kahana, D.E.; Pang, Y. |; Kahana, S.H.

    1996-06-01

    A quantitative model, based on hadronic physics and Monte Carlo cascading is applied to heavy ion collisions at BNL-AGS and BEVALAC energies. The model was found to be in excellent agreement with particle spectra where data previously existed, for Si beams, and was able to successfully predict the spectra where data was initially absent, for Au beams. For Si + Au collisions baryon densities of three or four times the normal nuclear matter density ({rho}{sub 0}) are seen in the theory, while for Au + Au collisions, matter at densities up to 10 {rho}{sub 0} is anticipated. The possibility that unusual states of matter may be created in the Au beams and potential signatures for its observation, in particular deuterons and collective flow, are considered.

  2. Energy Flow: Flow Charts Illustrating United States Energy Resources and Usage, from Lawrence Livermore National Laboratory

    DOE Data Explorer

    Decision makers have long recognized the importance of visualizing energy and material flows in a way that distinguishes between resources, transformations and services. Research priorities can be defined in terms of changes to the flows, and the consequences of policy or technology shifts can be traced both upstream and downstream. The usefulness of this top-down view is limited by the level of detail that can be conveyed in a single image. We use two techniques to balance information content with readability. First we employe visualization techniques, such as those embodied in the energy Sankey diagram below (Figure 1), to display both qualitative (relative line weight) and quantitative (listed values) information in a reader-friendly package. The second method is to augment static images with dynamic, scalable digital content containing multiple layers (e.g. energy, carbon and economic data). This transitions the audience from that of a passive reader to an active user of the information. When used in conjunction these approaches enable relatively large, interconnected processes to be described and analyzed efficiently. [copied from the description at http://en.openei.org/wiki/LLNL_Energy_Flow_Charts#cite_note-1

  3. Assessment of Interval Data and Their Potential Application to Residential Electricity End-Use Modeling, An

    EIA Publications

    2015-01-01

    The Energy Information Administration (EIA) is investigating the potential benefits of incorporating interval electricity data into its residential energy end use models. This includes interval smart meter and submeter data from utility assets and systems. It is expected that these data will play a significant role in informing residential energy efficiency policies in the future. Therefore, a long-term strategy for improving the RECS end-use models will not be complete without an investigation of the current state of affairs of submeter data, including their potential for use in the context of residential building energy modeling.

  4. Asymmetric energy flow in liquid alkylbenzenes: A computational study

    SciTech Connect

    Leitner, David M.; Pandey, Hari Datt

    2015-10-14

    Ultrafast IR-Raman experiments on substituted benzenes [B. C. Pein et al., J. Phys. Chem. B 117, 10898–10904 (2013)] reveal that energy can flow more efficiently in one direction along a molecule than in others. We carry out a computational study of energy flow in the three alkyl benzenes, toluene, isopropylbenzene, and t-butylbenzene, studied in these experiments, and find an asymmetry in the flow of vibrational energy between the two chemical groups of the molecule due to quantum mechanical vibrational relaxation bottlenecks, which give rise to a preferred direction of energy flow. We compare energy flow computed for all modes of the three alkylbenzenes over the relaxation time into the liquid with energy flow through the subset of modes monitored in the time-resolved Raman experiments and find qualitatively similar results when using the subset compared to all the modes.

  5. Energy flow in an arctic aquatic ecosystem

    SciTech Connect

    Schell, D.M.

    1988-01-01

    Natural isotope abundances to trace major pathways of energy flow to consumers in Imnavait Creek and the tundra ecosystem of the R4D watershed with comparative work in the coastal tundra. Our overall goals are to a determine if carbon is accumulating in upland and coastal tundra; determine the role of eroded peat carbon in the aquatic ecosystem; and to determine the distribution of carbon and nitrogen isotopes in the tundra-pond ecosystem to establish the feasibility of using natural differences as tracers. Past work on fishes, birds, and the prey species of insects and aquatic crustaceans has shown that peat carbon is very important in the energy supply supporting the food webs over the course of the year. Obligate freshwater fishes from the coastal lakes and Colville River have been shown to contain up to 60 percent peat carbon at the end of the winter season. In contrast, migratory shorebirds and passerines contained much smaller radiocarbon abundances in summer, indicating a major shift to recent in situ primary production in pond and stream ecosystems in summer months. For the past two years, we have narrowed our focus to the processes supplying carbon to the beaded stream system at MS-117 and have concentrated on determining the transfer and accumulation rates of carbon in the watershed.

  6. Energy flow in an arctic aquatic ecosystem

    SciTech Connect

    Schell, D.M.

    1988-12-31

    Natural isotope abundances to trace major pathways of energy flow to consumers in Imnavait Creek and the tundra ecosystem of the R4D watershed with comparative work in the coastal tundra. Our overall goals are to a determine if carbon is accumulating in upland and coastal tundra; determine the role of eroded peat carbon in the aquatic ecosystem; and to determine the distribution of carbon and nitrogen isotopes in the tundra-pond ecosystem to establish the feasibility of using natural differences as tracers. Past work on fishes, birds, and the prey species of insects and aquatic crustaceans has shown that peat carbon is very important in the energy supply supporting the food webs over the course of the year. Obligate freshwater fishes from the coastal lakes and Colville River have been shown to contain up to 60 percent peat carbon at the end of the winter season. In contrast, migratory shorebirds and passerines contained much smaller radiocarbon abundances in summer, indicating a major shift to recent in situ primary production in pond and stream ecosystems in summer months. For the past two years, we have narrowed our focus to the processes supplying carbon to the beaded stream system at MS-117 and have concentrated on determining the transfer and accumulation rates of carbon in the watershed.

  7. Oxidative gelation measurement and influence on soft wheat batter viscosity and end-use quality.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Viscosity is an important end-use attribute for some soft wheat flour formulations. Specifically, in formulations with minimal gluten development, such as batters (cake, pancake and doughnut) and coatings (tempura), viscosity is important to leavening gas retention and flow characteristics. Current ...

  8. Energy structure of MHD flow coupling with outer resistance circuit

    NASA Astrophysics Data System (ADS)

    Huang, Z. Y.; Liu, Y. J.; Chen, Y. Q.; Peng, Z. L.

    2015-08-01

    Energy structure of MHD flow coupling with outer resistance circuit is studied to illuminate qualitatively and quantitatively the energy relation of this basic MHD flow system with energy input and output. Energy structure are analytically derived based on the Navier-Stocks equations for two-dimensional fully-developed flow and generalized Ohm's Law. The influences of applied magnetic field, Hall parameter and conductivity on energy structure are discussed based on the analytical results. Associated energies in MHD flow are deduced and validated by energy conservation. These results reveal that energy structure consists of two sub structures: electrical energy structure and internal energy structure. Energy structure and its sub structures provide an integrated theoretical energy path of the MHD system. Applied magnetic field and conductivity decrease the input energy, dissipation by fluid viscosity and internal energy but increase the ratio of electrical energy to input energy, while Hall parameter has the opposite effects. These are caused by their different effects on Bulk velocity, velocity profiles, voltage and current in outer circuit. Understanding energy structure helps MHD application designers to actively adjust the allocation of different parts of energy so that it is more reasonable and desirable.

  9. A Field Course Based on the Community Energy Flow Approach

    ERIC Educational Resources Information Center

    Townsend, Colin; Phillipson, John

    1977-01-01

    The concept of community energy flow provides a basis for a field course. This paper describes the methodology used in a field course for estimating parameters and for monitoring physical environmental variables. The paper culminates in the construction of a model of energy flow through the community. (Author/MA)

  10. Energy conservation with automatic flow control valves

    SciTech Connect

    Phillips, D.

    1984-12-01

    Automatic flow control valves are offered in a wide range of sizes starting at 1/2 in. with flow rates of 0.5 gpm and up. They are also provided with materials and end connections to meet virtually any fan-coil system requirement. Among these are copper sweat type valves; ductile iron threaded valves; male/female threaded brass valves; and combination flow control/ball valves with union ends.

  11. Pump energy and flow balance analysis

    SciTech Connect

    Carlson, G.F.

    1982-10-01

    The purpose is to illustrate simple circuit flow analysis techniques that will enable design engineers to identify and provide protection against short circuiting (flow unbalance) for new design. Removal of short circuit fears should help reduce the tendency to oversize HVAC pumps. Presented analysis techniques will establish methods for flow balance in existing buildings and will permit a considerable reduction in pump power requirements. Explains the relationship between pump power draw and operating cost. Shows how, for any given total system flow rate, the actual flow rate entering each riser and, consequently, each terminal unit can be determined. Generalizes that if the driving differential head across the subcircuit remains constant, then if the subcircuit head loss (exclusive of the valve) at design flow is very low, flow change in the subcircuit caused by a change in balance valve setting will be of high order and will follow balance valve characteristics; and if the subcircuit head loss is high, adjustment of the balance valve will only cause a minor order flow change. These simplified techniques should provide protection against flow unbalance and oversizing of HVAC pumps.

  12. Character of energy flow in air shower core

    NASA Technical Reports Server (NTRS)

    Mizushima, K.; Asakimori, K.; Maeda, T.; Kameda, T.; Misaki, Y.

    1985-01-01

    Energy per charged particle near the core of air showers was measured by 9 energy flow detectors, which were the combination of Cerenkov counters and scintillators. Energy per particle of each detector was normalized to energy at 2m from the core. The following results were obtained as to the energy flow: (1) integral frequency distribution of mean energy per particle (averaged over 9 detectors) is composed of two groups separated distinctly; and (2) showers contained in one group show an anisotropy of arrival direction.

  13. Energy studies on central and variable refrigerant flow air-conditioning systems

    NASA Astrophysics Data System (ADS)

    Abdullah, H.; Nitamakwuavan, S.; Jalaludin, A. F.

    2012-06-01

    Air-conditioning is a major contributor to energy end-use in commercial buildings. Different types of airconditioning systems are installed in commercial buildings including packaged systems, split units and central systems. With the advancement in control technology and the demand for energy efficient systems, variable refrigerant flow (VRF) air-conditioning system is seen to be a solution to the load-matching problem for airconditioning systems. In a VRF system, the volume or flow rate of the refrigerant is accurately matched to the required cooling load thereby saving energy and providing more accurate control. This study aims to determine the performance of the VRF system used in an actual building by calculating the Coefficient of Performance (COP) of the system. The COP is then compared to the COP of a centralized chilled water system used in the same building. The results showed that the COPs determined for the VRF and central systems are 3.3 and 2.0 respectively. The results also indicated that replacing older central system with a VRF system could lead to an energy savings of up to 39.5%.

  14. Numerical Laser Energy Deposition on Supersonic Cavity Flow and Sensor Placement Strategies to Control the Flow

    PubMed Central

    Aradag, Selin

    2013-01-01

    In this study, the impact of laser energy deposition on pressure oscillations and relative sound pressure levels (SPL) in an open supersonic cavity flow is investigated. Laser energy with a magnitude of 100 mJ is deposited on the flow just above the cavity leading edge and up to 7 dB of reduction is obtained in the SPL values along the cavity back wall. Additionally, proper orthogonal decomposition (POD) method is applied to the x-velocity data obtained as a result of computational fluid dynamics simulations of the flow with laser energy deposition. Laser is numerically modeled using a spherically symmetric temperature distribution. By using the POD results, the effects of laser energy on the flow mechanism are presented. A one-dimensional POD methodology is applied to the surface pressure data to obtain critical locations for the placement of sensors for real time flow control applications. PMID:24363612

  15. Numerical laser energy deposition on supersonic cavity flow and sensor placement strategies to control the flow.

    PubMed

    Yilmaz, Ibrahim; Aradag, Selin

    2013-01-01

    In this study, the impact of laser energy deposition on pressure oscillations and relative sound pressure levels (SPL) in an open supersonic cavity flow is investigated. Laser energy with a magnitude of 100 mJ is deposited on the flow just above the cavity leading edge and up to 7 dB of reduction is obtained in the SPL values along the cavity back wall. Additionally, proper orthogonal decomposition (POD) method is applied to the x-velocity data obtained as a result of computational fluid dynamics simulations of the flow with laser energy deposition. Laser is numerically modeled using a spherically symmetric temperature distribution. By using the POD results, the effects of laser energy on the flow mechanism are presented. A one-dimensional POD methodology is applied to the surface pressure data to obtain critical locations for the placement of sensors for real time flow control applications. PMID:24363612

  16. Anisotropic energy flow and allosteric ligand binding in albumin

    NASA Astrophysics Data System (ADS)

    Li, Guifeng; Magana, Donny; Dyer, R. Brian

    2014-01-01

    Allosteric interactions in proteins generally involve propagation of local structural changes through the protein to a remote site. Anisotropic energy transport is thought to couple the remote sites, but the nature of this process is poorly understood. Here, we report the relationship between energy flow through the structure of bovine serum albumin and allosteric interactions between remote ligand binding sites of the protein. Ultrafast infrared spectroscopy is used to probe the flow of energy through the protein backbone following excitation of a heater dye, a metalloporphyrin or malachite green, bound to different binding sites in the protein. We observe ballistic and anisotropic energy flow through the protein structure following input of thermal energy into the flexible ligand binding sites, without local heating of the rigid helix bundles that connect these sites. This efficient energy transport mechanism enables the allosteric propagation of binding energy through the connecting helix structures.

  17. The Role of Water Vapour in Earth's Energy Flows

    NASA Astrophysics Data System (ADS)

    Allan, Richard P.

    2012-07-01

    Water vapour modulates energy flows in Earth's climate system through transfer of latent heat by evaporation and condensation and by modifying the flows of radiative energy both in the longwave and shortwave portions of the electromagnetic spectrum. This article summarizes the role of water vapour in Earth's energy flows with particular emphasis on (1) the powerful thermodynamic constraint of the Clausius Clapeyron equation, (2) dynamical controls on humidity above the boundary layer (or free-troposphere), (3) uncertainty in continuum absorption in the relatively transparent "window" regions of the radiative spectrum and (4) implications for changes in the atmospheric hydrological cycle.

  18. Stocks, Flows, and Prospects of Energy

    SciTech Connect

    Loschel, Andrea; Johnston, John; Delucchi, Mark A; Demayo, Trevor N; Gautier, Donald L; Greene, David L; Ogden, Joan; Rayner, Steve; Worrell, Ernst

    2010-01-01

    Analyses of future energy systems have typically focused on energy sufficiency and climate change issues. While the potential supply of energy services will probably not constrain us in the immediate future, there are limits imposed on the energy system by climate change considerations, which, in turn, are inextricably bound up with land, water, and nonrenewable mineral resources issues. These could pose constraints to energy systems that may not have been fully accounted for in current analyses. There is a pressing lack of knowledge on the boundaries that will impact a sustainable energy system. A more integrated view of energy sustainability is necessary to ensure the well-being of current and future generations. This chapter proposes a set of measures related to sustainability within the context of selected energy scenarios and develops a methodology to define and measure relevant quantities and important links to other resource areas.

  19. Stocks, Flows, and Prospects of Energy

    SciTech Connect

    Loschel, Andrea; Johnston, John; Delucchi, Mark A; Demayo, Trevor N; Gautier, Donald L; Greene, David L; Ogden, Joan; Rayner, Steve; Worrell, Ernst

    2009-01-01

    Analyses of future energy systems have typically focused on energy suffi ciency and climate change issues. While the potential supply of energy services will probably not constrain us in the immediate future, there are limits imposed on the energy system by climate change considerations, which, in turn, are inextricably bound up with land, water, and nonrenewable mineral resources issues. These could pose constraints to energy systems that may not have been fully accounted for in current analyses. There is a pressing lack of knowledge on the boundaries that will impact a sustainable energy system. A more integrated view of energy sustainability is necessary to ensure the well-being of current and future generations. This chapter proposes a set of measures related to sustainability within the context of selected energy scenarios and develops a methodology to define and measure relevant quantities and important links to other resource areas.

  20. End-Use Opportunity Analysis from Progress Indicator Results for ASHRAE Standard 90.1-2013

    SciTech Connect

    Hart, Philip R.; Xie, YuLong

    2015-02-05

    This report and an accompanying spreadsheet (PNNL 2014a) compile the end use building simulation results for prototype buildings throughout the United States. The results represent he energy use of each edition of ASHRAE Standard 90.1, Energy Standard for Buildings Except Low-Rise Residential Buildings (ASHRAE 2004, 2007, 2010, 2013). PNNL examined the simulation results to determine how the remaining energy was used.

  1. Radiant energy receiver having improved coolant flow control means

    DOEpatents

    Hinterberger, H.

    1980-10-29

    An improved coolant flow control for use in radiant energy receivers of the type having parallel flow paths is disclosed. A coolant performs as a temperature dependent valve means, increasing flow in the warmer flow paths of the receiver, and impeding flow in the cooler paths of the receiver. The coolant has a negative temperature coefficient of viscosity which is high enough such that only an insignificant flow through the receiver is experienced at the minimum operating temperature of the receiver, and such that a maximum flow is experienced at the maximum operating temperature of the receiver. The valving is accomplished by changes in viscosity of the coolant in response to the coolant being heated and cooled. No remotely operated valves, comparators or the like are needed.

  2. Self-powered water splitting using flowing kinetic energy.

    PubMed

    Tang, Wei; Han, Yu; Han, Chang Bao; Gao, Cai Zhen; Cao, Xia; Wang, Zhong Lin

    2015-01-14

    By utilizing a water-flow-driven triboelectric nanogenerator, a fully self-powered water-splitting process is demonstrated using the electricity converted from a water flow without additional energy costs. Considering the extremely low costs, the demonstrated approach is universally applicable and practically usable for future water electrolysis, which may initiate a research direction in the field of triboelectrolysis and possibly impacts energy science in general.

  3. Measurement of energy distribution in flowing hydrogen microwave plasmas

    NASA Technical Reports Server (NTRS)

    Chapman, R.; Morin, T.; Finzel, M.; Hawley, M. C.

    1985-01-01

    An electrothermal propulsion concept utilizing a microwave plasma system as the mechanism to convert electromagnetic energy into kinetic energy of a flowing gas is investigated. A calorimetry system enclosing a microwave plasma system has been developed to accurately measure the energy inputs and outputs of the microwave plasma system. The rate of energy transferred to the gas can be determined to within + or - 1.8 W from an energy balance around the microwave plasma system. The percentage of the power absorbed by the microwave plasma system transferred to the hydrogen gas as it flows through the system is found to increase with the increasing flow rate, to decrease with the increasing pressure, and to be independent of the absorbed power. An upper bound for the hydrogen gas temperature is estimated from the energy content, heat capacity, and flow rate of the gas stream. A lower bound for an overall heat-transfer coefficient is then calculated, characterizing the energy loss from the hydrogen gas stream to the air cooling of the plasma discharge tube wall. The heat-transfer coefficient is found to increase with the increasing flow rate and pressure and to be independent of the absorbed power. This result indicates that a convective-type mechanism is responsible for the energy transfer.

  4. Energy flow: image correspondence approximation for motion analysis

    NASA Astrophysics Data System (ADS)

    Wang, Liangliang; Li, Ruifeng; Fang, Yajun

    2016-04-01

    We propose a correspondence approximation approach between temporally adjacent frames for motion analysis. First, energy map is established to represent image spatial features on multiple scales using Gaussian convolution. On this basis, energy flow at each layer is estimated using Gauss-Seidel iteration according to the energy invariance constraint. More specifically, at the core of energy invariance constraint is "energy conservation law" assuming that the spatial energy distribution of an image does not change significantly with time. Finally, energy flow field at different layers is reconstructed by considering different smoothness degrees. Due to the multiresolution origin and energy-based implementation, our algorithm is able to quickly address correspondence searching issues in spite of background noise or illumination variation. We apply our correspondence approximation method to motion analysis, and experimental results demonstrate its applicability.

  5. GridLAB-D Technical Support Document: Residential End-Use Module Version 1.0

    SciTech Connect

    Taylor, Zachary T.; Gowri, Krishnan; Katipamula, Srinivas

    2008-07-31

    1.0 Introduction The residential module implements the following end uses and characteristics to simulate the power demand in a single family home: • Water heater • Lights • Dishwasher • Range • Microwave • Refrigerator • Internal gains (plug loads) • House (heating/cooling loads) The house model considers the following four major heat gains/losses that contribute to the building heating/cooling load: 1. Conduction through exterior walls, roof and fenestration (based on envelope UA) 2. Air infiltration (based on specified air change rate) 3. Solar radiation (based on CLTD model and using tmy data) 4. Internal gains from lighting, people, equipment and other end use objects. The Equivalent Thermal Parameter (ETP) approach is used to model the residential loads and energy consumption. The following sections describe the modeling assumptions for each of the above end uses and the details of power demand calculations in the residential module.

  6. Bootstrapping the energy flow in the beginning of life.

    PubMed

    Hengeveld, R; Fedonkin, M A

    2007-01-01

    This paper suggests that the energy flow on which all living structures depend only started up slowly, the low-energy, initial phase starting up a second, slightly more energetic phase, and so on. In this way, the build up of the energy flow follows a bootstrapping process similar to that found in the development of computers, the first generation making possible the calculations necessary for constructing the second one, etc. In the biogenetic upstart of an energy flow, non-metals in the lower periods of the Periodic Table of Elements would have constituted the most primitive systems, their operation being enhanced and later supplanted by elements in the higher periods that demand more energy. This bootstrapping process would put the development of the metabolisms based on the second period elements carbon, nitrogen and oxygen at the end of the evolutionary process rather than at, or even before, the biogenetic event.

  7. A new energy transfer model for turbulent free shear flow

    NASA Technical Reports Server (NTRS)

    Liou, William W.-W.

    1992-01-01

    A new model for the energy transfer mechanism in the large-scale turbulent kinetic energy equation is proposed. An estimate of the characteristic length scale of the energy containing large structures is obtained from the wavelength associated with the structures predicted by a weakly nonlinear analysis for turbulent free shear flows. With the inclusion of the proposed energy transfer model, the weakly nonlinear wave models for the turbulent large-scale structures are self-contained and are likely to be independent flow geometries. The model is tested against a plane mixing layer. Reasonably good agreement is achieved. Finally, it is shown by using the Liapunov function method, the balance between the production and the drainage of the kinetic energy of the turbulent large-scale structures is asymptotically stable as their amplitude saturates. The saturation of the wave amplitude provides an alternative indicator for flow self-similarity.

  8. Refining and End Use Study of Coal Liquids

    SciTech Connect

    1997-10-01

    This report summarizes revisions to the design basis for the linear programing refining model that is being used in the Refining and End Use Study of Coal Liquids. This revision primarily reflects the addition of data for the upgrading of direct coal liquids.

  9. Spectral kinetic energy transfer in turbulent premixed reacting flows.

    PubMed

    Towery, C A Z; Poludnenko, A Y; Urzay, J; O'Brien, J; Ihme, M; Hamlington, P E

    2016-05-01

    Spectral kinetic energy transfer by advective processes in turbulent premixed reacting flows is examined using data from a direct numerical simulation of a statistically planar turbulent premixed flame. Two-dimensional turbulence kinetic-energy spectra conditioned on the planar-averaged reactant mass fraction are computed through the flame brush and variations in the spectra are connected to terms in the spectral kinetic energy transport equation. Conditional kinetic energy spectra show that turbulent small-scale motions are suppressed in the burnt combustion products, while the energy content of the mean flow increases. An analysis of spectral kinetic energy transfer further indicates that, contrary to the net down-scale transfer of energy found in the unburnt reactants, advective processes transfer energy from small to large scales in the flame brush close to the products. Triadic interactions calculated through the flame brush show that this net up-scale transfer of energy occurs primarily at spatial scales near the laminar flame thermal width. The present results thus indicate that advective processes in premixed reacting flows contribute to energy backscatter near the scale of the flame.

  10. Spectral kinetic energy transfer in turbulent premixed reacting flows

    NASA Astrophysics Data System (ADS)

    Towery, C. A. Z.; Poludnenko, A. Y.; Urzay, J.; O'Brien, J.; Ihme, M.; Hamlington, P. E.

    2016-05-01

    Spectral kinetic energy transfer by advective processes in turbulent premixed reacting flows is examined using data from a direct numerical simulation of a statistically planar turbulent premixed flame. Two-dimensional turbulence kinetic-energy spectra conditioned on the planar-averaged reactant mass fraction are computed through the flame brush and variations in the spectra are connected to terms in the spectral kinetic energy transport equation. Conditional kinetic energy spectra show that turbulent small-scale motions are suppressed in the burnt combustion products, while the energy content of the mean flow increases. An analysis of spectral kinetic energy transfer further indicates that, contrary to the net down-scale transfer of energy found in the unburnt reactants, advective processes transfer energy from small to large scales in the flame brush close to the products. Triadic interactions calculated through the flame brush show that this net up-scale transfer of energy occurs primarily at spatial scales near the laminar flame thermal width. The present results thus indicate that advective processes in premixed reacting flows contribute to energy backscatter near the scale of the flame.

  11. Variable flow -- the quest for system energy efficiency

    SciTech Connect

    Eppelheimer, D.M.

    1996-12-31

    Varying condenser water flow has long been used as a method of controlling head pressure in water-cooled refrigeration systems. This method of head pressure control has been applied successfully on systems with scroll, reciprocating, heli-rotor, and centrifugal compressors. Condenser water flow is altered either by bypassing the condenser via a three-way valve or by throttling flow with a two-way valve. Today, the affordability and potential energy savings of adjustable speed drives makes this the preferred method of varying flow. In the quest for greater energy savings, many designers propose to vary the flow of water through the evaporators of chillers also. This feat is not as easily accomplished as the first. There are system designs that allow variable flow of chilled water at the system level while maintaining constant flow through the chiller evaporator. Yet in spite of the risk and the presence of other variable options, some still wish to vary the flow of chilled water through the evaporator by large proportions. Can it be done? Of course! However, there are a few engineering problems that must be tackled to accomplish this feat. This paper delineates those problems.

  12. Mechanical energy flow models of rods and beams

    NASA Technical Reports Server (NTRS)

    Wohlever, J. C.; Bernhard, R. J.

    1992-01-01

    It has been proposed that the flow of mechanical energy through a structural/acoustic system may be modeled in a manner similar to that of flow of thermal energy/in a heat conduction problem. If this hypothesis is true, it would result in relatively efficient numerical models of structure-borne energy in large built-up structures. Fewer parameters are required to approximate the energy solution than are required to model the characteristic wave behavior of structural vibration by using traditional displacement formulations. The energy flow hypothesis is tested in this investigation for both longitudinal vibration in rods and transverse flexural vibrations of beams. The rod is shown to behave approximately according to the thermal energy flow analogy. However, the beam solutions behave significantly differently than predicted by the thermal analogy unless locally-space-averaged energy and power are considered. Several techniques for coupling dissimilar rods and beams are also discussed. Illustrations of the solution accuracy of the methods are included.

  13. High energy density redox flow device

    DOEpatents

    Chiang, Yet -Ming; Carter, W. Craig; Duduta, Mihai; Limthongkul, Pimpa

    2015-10-06

    Redox flow devices are described including a positive electrode current collector, a negative electrode current collector, and an ion-permeable membrane separating said positive and negative current collectors, positioned and arranged to define a positive electroactive zone and a negative electroactive zone; wherein at least one of said positive and negative electroactive zone comprises a flowable semi-solid composition comprising ion storage compound particles capable of taking up or releasing said ions during operation of the cell, and wherein the ion storage compound particles have a polydisperse size distribution in which the finest particles present in at least 5 vol % of the total volume, is at least a factor of 5 smaller than the largest particles present in at least 5 vol % of the total volume.

  14. High energy density redox flow device

    DOEpatents

    Chiang, Yet-Ming; Carter, William Craig; Duduta, Mihai; Limthongkul, Pimpa

    2014-05-13

    Redox flow devices are described including a positive electrode current collector, a negative electrode current collector, and an ion-permeable membrane separating said positive and negative current collectors, positioned and arranged to define a positive electroactive zone and a negative electroactive zone; wherein at least one of said positive and negative electroactive zone comprises a flowable semi-solid composition comprising ion storage compound particles capable of taking up or releasing said ions during operation of the cell, and wherein the ion storage compound particles have a polydisperse size distribution in which the finest particles present in at least 5 vol % of the total volume, is at least a factor of 5 smaller than the largest particles present in at least 5 vol % of the total volume.

  15. Transport of energy by disturbances in arbitrary steady flows

    NASA Technical Reports Server (NTRS)

    Myers, M. K.

    1991-01-01

    An exact equation governing the transport of energy associated with disturbances in an arbitrary steady flow is derived. The result is a generalization of the familiar concept of acoustic energy and is suggested by a perturbation expansion of the general energy equation of fluid mechanics. A disturbance energy density and flux are defined and identified as exact fluid dynamic quantities whose leading-order regular perturbation representations reduce in various special cases to previously known results. The exact equation on disturbance energy is applied to a simple example of nonlinear wave propagation as an illustration of its general utility in situations where a linear description of the disturbance is inadequate.

  16. REFINING AND END USE STUDY OF COAL LIQUIDS

    SciTech Connect

    Unknown

    2002-01-01

    This document summarizes all of the work conducted as part of the Refining and End Use Study of Coal Liquids. There were several distinct objectives set, as the study developed over time: (1) Demonstration of a Refinery Accepting Coal Liquids; (2) Emissions Screening of Indirect Diesel; (3) Biomass Gasification F-T Modeling; and (4) Updated Gas to Liquids (GTL) Baseline Design/Economic Study.

  17. Hydrogen-Bromine Flow Battery: Hydrogen Bromine Flow Batteries for Grid Scale Energy Storage

    SciTech Connect

    2010-10-01

    GRIDS Project: LBNL is designing a flow battery for grid storage that relies on a hydrogen-bromine chemistry which could be more efficient, last longer and cost less than today’s lead-acid batteries. Flow batteries are fundamentally different from traditional lead-acid batteries because the chemical reactants that provide their energy are stored in external tanks instead of inside the battery. A flow battery can provide more energy because all that is required to increase its storage capacity is to increase the size of the external tanks. The hydrogen-bromine reactants used by LBNL in its flow battery are inexpensive, long lasting, and provide power quickly. The cost of the design could be well below $100 per kilowatt hour, which would rival conventional grid-scale battery technologies.

  18. An integral turbulent kinetic energy analysis of free shear flows

    NASA Technical Reports Server (NTRS)

    Peters, C. E.; Phares, W. J.

    1973-01-01

    Mixing of coaxial streams is analyzed by application of integral techniques. An integrated turbulent kinetic energy (TKE) equation is solved simultaneously with the integral equations for the mean flow. Normalized TKE profile shapes are obtained from incompressible jet and shear layer experiments and are assumed to be applicable to all free turbulent flows. The shear stress at the midpoint of the mixing zone is assumed to be directly proportional to the local TKE, and dissipation is treated with a generalization of the model developed for isotropic turbulence. Although the analysis was developed for ducted flows, constant-pressure flows were approximated with the duct much larger than the jet. The axisymmetric flows under consideration were predicted with reasonable accuracy. Fairly good results were also obtained for the fully developed two-dimensional shear layers, which were computed as thin layers at the boundary of a large circular jet.

  19. Allosteric Ligand Binding and Anisotropic Energy Flow in Albumin

    NASA Astrophysics Data System (ADS)

    Dyer, Brian

    2014-03-01

    Protein allostery usually involves propagation of local structural changes through the protein to a remote site. Coupling of structural changes at remote sites is thought to occur through anisotropic energy transport, but the nature of this process is poorly understood. We have studied the relationship between allosteric interactions of remote ligand binding sites of the protein and energy flow through the structure of bovine serum albumin (BSA). We applied ultrafast infrared spectroscopy to probe the flow of energy through the protein backbone following excitation of a heater dye, a metalloporphyrin or malachite green, bound to different binding sites in the protein. We observe ballistic flow through the protein structure following input of thermal energy into the flexible ligand binding sites. We also observe anisotropic heat flow through the structure, without local heating of the rigid helix bundles that connect these sites. We will discuss the implications of this efficient energy transport mechanism with regard to the allosteric propagation of binding energy through the connecting helix structures.

  20. Energy flow in an arctic aquatic ecosystem

    SciTech Connect

    Schell, D.M.

    1983-01-01

    This component of the terrestrial-aquatic interaction group seeks to use the natural stable carbon isotope ratios and radiocarbon abundances to trace the movement of photosynthate from the terrestrial environment to the stream system at MS-117. In addition to estimating the total flux, we will also attempt to describe the relative fractions derived from modern primary production and that derived from delayed inputs of eroded peat. We will also seek to determine the coupling efficiency of these energy sources to the invertebrate faunal populations in the tundra soils and streams.

  1. Energy flow in an arctic aquatic ecosystem

    SciTech Connect

    Schell, D.M.

    1983-12-31

    This component of the terrestrial-aquatic interaction group seeks to use the natural stable carbon isotope ratios and radiocarbon abundances to trace the movement of photosynthate from the terrestrial environment to the stream system at MS-117. In addition to estimating the total flux, we will also attempt to describe the relative fractions derived from modern primary production and that derived from delayed inputs of eroded peat. We will also seek to determine the coupling efficiency of these energy sources to the invertebrate faunal populations in the tundra soils and streams.

  2. Analysis of Motorcycle Weave Mode by using Energy Flow Method

    NASA Astrophysics Data System (ADS)

    Marumo, Yoshitaka; Katayama, Tsuyoshi

    The activation mechanism of motorcycle weave mode is clarified within the framework of the energy flow method, which calculates energy flow of mechanical forces in each motion. It is demonstrated that only a few mechanical forces affect the stability of the weave mode from among a total of about 40 mechanical forces. The activation of the lateral, yawing and rolling motions destabilize the weave mode, while activation of the steering motion stabilizes the weave mode. A detailed investigation of the energy flow of the steering motion reveals that the steering motion plays an important role in clarifying the characteristics of the weave mode. As activation of the steering motion progresses the phase of the front tire side force, and the weave mode is consequently stabilized. This paper provides a design guide for stabilizing the weave mode and the wobble mode compatibility.

  3. Study of energy flows in Pantanal - Brazil

    NASA Astrophysics Data System (ADS)

    Santanna, F. B.; Arruda, P. H. Z. D.; Pinto-Jr, O. B.

    2014-12-01

    The main goal of this work was to estimate fluxes using the eddy covariance method in a wetland area, basically with herb-shrub physiognomy, sparse woody vegetation and approximately 4m height. The geographical position of the Pantanal, altitude, latitude, longitude, climate and weather conditions are determined by the dynamics of the atmosphere that affects the whole South America and consequently influence the ecological framework of ecosystems. The results shown by the components considered in the energy balance were more significant during the day, which the atmospheric boundary layer extends from the ground to about 50 or 100 meters height, showing greater instability and turbulence (u* > 0.2 m / s), and this turbulence is what justifies the use of the eddy covariance method to estimate the sensible and latent heat flux. The Pantanal presents seasonal difference between the densities estimates of sensible (H) and latent (LE) heat flux. During the rainy season the sensible heat flux (H) was 30% and the latent heat flux (LE) 58%. During the dry season the sensible heat flux (H) was 46% and the latent heat flux (LE) 40% of the energy budget.

  4. Distributed Power Flow Control: Distributed Power Flow Control using Smart Wires for Energy Routing

    SciTech Connect

    2012-04-24

    GENI Project: Smart Wire Grid is developing a solution for controlling power flow within the electric grid to better manage unused and overall transmission capacity. The 300,000 miles of high-voltage transmission line in the U.S. today are congested and inefficient, with only around 50% of all transmission capacity utilized at any given time. Increased consumer demand should be met in part with more efficient and an economical power flow. Smart Wire Grid’s devices clamp onto existing transmission lines and control the flow of power within—much like how internet routers help allocate bandwidth throughout the web. Smart wires could support greater use of renewable energy by providing more consistent control over how that energy is routed within the grid on a real-time basis. This would lessen the concerns surrounding the grid’s inability to effectively store intermittent energy from renewables for later use.

  5. Vibrational Energy Transfer of Diatomic Gases in Hypersonic Expanding Flows.

    NASA Astrophysics Data System (ADS)

    Ruffin, Stephen Merrick

    In high temperature flows related to vehicles at hypersonic speeds significant excitation of the vibrational energy modes of the gas can occur. Accurate predictions of the vibrational state of the gas and the rates of vibrational energy transfer are essential to achieve optimum engine performance, for design of heat shields, and for studies of ground based hypersonic test facilities. The Landau -Teller relaxation model is widely used because it has been shown to give accurate predictions in vibrationally heating flows such as behind forebody shocks. However, a number of experiments in nozzles have indicated that it fails to accurately predict the rate of energy transfer in expanding, or cooling, flow regions and fails to predict the distribution of energy in the vibrational quantum levels. The present study examines the range of applicability of the Landau -Teller model in expanding flows and develops techniques which provide accurate predictions in expanding flows. In the present study, detailed calculations of the vibrational relaxation process of N_2 and CO in cooling flows are conducted. A coupled set of vibrational transition rate equations and quasi one-dimensional fluid dynamic equations is solved. Rapid anharmonic Vibration-Translation transition rates and Vibration -Vibration exchange collisions are found to be responsible for vibrational relaxation acceleration in situations of high vibrational temperature and low translational temperature. The predictions of the detailed master equation solver are in excellent agreement with experimental results. The exact degree of acceleration is cataloged in this study for N_2 and is found to be a function of both the translational temperature (T) and the ratio of vibrational to translational temperatures (T_{vib}/T). Non-Boltzmann population distributions are observed for values of T _{vib}/T as low as 2.0. The local energy transfer rate is shown to be an order of magnitude or more faster than the Landau-Teller model

  6. Analysis of PG&E`s residential end-use metered data to improve electricity demand forecasts

    SciTech Connect

    Eto, J.H.; Moezzi, M.M.

    1992-06-01

    It is generally acknowledged that improvements to end-use load shape and peak demand forecasts for electricity are limited primarily by the absence of reliable end-use data. In this report we analyze recent end-use metered data collected by the Pacific Gas and Electric Company from more than 700 residential customers to develop new inputs for the load shape and peak demand electricity forecasting models used by the Pacific Gas and Electric Company and the California Energy Commission. Hourly load shapes are normalized to facilitate separate accounting (by the models) of annual energy use and the distribution of that energy use over the hours of the day. Cooling electricity consumption by central air-conditioning is represented analytically as a function of climate. Limited analysis of annual energy use, including unit energy consumption (UEC), and of the allocation of energy use to seasons and system peak days, is also presented.

  7. Estimating end-use emissions factors for policy analysis: the case of space cooling and heating.

    PubMed

    Jacobsen, Grant D

    2014-06-17

    This paper provides the first estimates of end-use specific emissions factors, which are estimates of the amount of a pollutant that is emitted when a unit of electricity is generated to meet demand from a specific end-use. In particular, this paper provides estimates of emissions factors for space cooling and heating, which are two of the most significant end-uses. The analysis is based on a novel two-stage regression framework that estimates emissions factors that are specific to cooling or heating by exploiting variation in cooling and heating demand induced by weather variation. Heating is associated with similar or greater CO2 emissions factor than cooling in all regions. The difference is greatest in the Midwest and Northeast, where the estimated CO2 emissions factor for heating is more than 20% larger than the emissions factor for cooling. The minor differences in emissions factors in other regions, combined with the substantial difference in the demand pattern for cooling and heating, suggests that the use of overall regional emissions factors is reasonable for policy evaluations in certain locations. Accurately quantifying the emissions factors associated with different end-uses across regions will aid in designing improved energy and environmental policies.

  8. Electricity end-use efficiency: Experience with technologies, markets, and policies throughout the world

    SciTech Connect

    Levine, M.D.; Koomey, J.; Price, L.; Geller, H.; Nadel, S.

    1992-03-01

    In its August meeting in Geneva, the Energy and Industry Subcommittee (EIS) of the Policy Response Panel of the Intergovernmental Panel on Climate Change (IPCC) identified a series of reports to be produced. One of these reports was to be a synthesis of available information on global electricity end-use efficiency, with emphasis on developing nations. The report will be reviewed by the IPCC and approved prior to the UN Conference on Environment and Development (UNCED), Brazil, June 1992. A draft outline for the report was submitted for review at the November 1991 meeting of the EIS. This outline, which was accepted by the EIS, identified three main topics to be addressed in the report: status of available technologies for increasing electricity end-use efficiency; review of factors currently limiting application of end-use efficiency technologies; and review of policies available to increase electricity end-use efficiency. The United States delegation to the EIS agreed to make arrangements for the writing of the report.

  9. Estimating end-use emissions factors for policy analysis: the case of space cooling and heating.

    PubMed

    Jacobsen, Grant D

    2014-06-17

    This paper provides the first estimates of end-use specific emissions factors, which are estimates of the amount of a pollutant that is emitted when a unit of electricity is generated to meet demand from a specific end-use. In particular, this paper provides estimates of emissions factors for space cooling and heating, which are two of the most significant end-uses. The analysis is based on a novel two-stage regression framework that estimates emissions factors that are specific to cooling or heating by exploiting variation in cooling and heating demand induced by weather variation. Heating is associated with similar or greater CO2 emissions factor than cooling in all regions. The difference is greatest in the Midwest and Northeast, where the estimated CO2 emissions factor for heating is more than 20% larger than the emissions factor for cooling. The minor differences in emissions factors in other regions, combined with the substantial difference in the demand pattern for cooling and heating, suggests that the use of overall regional emissions factors is reasonable for policy evaluations in certain locations. Accurately quantifying the emissions factors associated with different end-uses across regions will aid in designing improved energy and environmental policies. PMID:24866122

  10. Direct measurement meter indicates real-time energy flow

    SciTech Connect

    Heyden, W.H.V. )

    1991-05-01

    The increased activity in transporting gas and the use of natural gas from widely varying sources has created a need to simplify measurement of energy transfers in natural gas operations. The natural gas industry requires an energy measurement device that is simple, cost effective and accurate. Such a device must be a direct measurement meter, easy to install, and one which will measure energy transfers in natural gas regardless of volume, composition, heating value, supercompressibility, inert fractions and temperature. These and other factors that are required for what presently is and remains, a calculation of energy in natural gas. The need then, is for a flow device which will measure and indicate direct, real-time energy flow and perform at pipe line conditions. A flow meter has been under development for seven years and has been in field testing for three years at 4 different sites under a Gas Research Institute (GRI) sponsored program. The field test objective is to measure and verify the meter's technical properties under actual field service conditions. In each field test site, the meter is continuously compared to existing gas flow measurement devices. Eact test site has different meter configurations which allow a broad scope of comparison and testing experience.

  11. Distributed energy storage: Time-dependent tree flow design

    NASA Astrophysics Data System (ADS)

    Bejan, A.; Ziaei, S.; Lorente, S.

    2016-05-01

    This article proposes "distributed energy storage" as a basic design problem of distributing energy storage material on an area. The energy flows by fluid flow from a concentrated source to points (users) distributed equidistantly on the area. The flow is time-dependent. Several scenarios are analyzed: sensible-heat storage, latent-heat storage, exergy storage vs energy storage, and the distribution of a finite supply of heat transfer surface between the source fluid and the distributed storage material. The chief conclusion is that the finite amount of storage material should be distributed proportionally with the distribution of the flow rate of heating agent arriving on the area. The total time needed by the source stream to "invade" the area is cumulative (the sum of the storage times required at each storage site) and depends on the energy distribution paths and the sequence in which the users are served by the source stream. Directions for future designs of distributed storage and retrieval are outlined in the concluding section.

  12. Energy flow along the medium-induced parton cascade

    NASA Astrophysics Data System (ADS)

    Blaizot, J.-P.; Mehtar-Tani, Y.

    2016-05-01

    We discuss the dynamics of parton cascades that develop in dense QCD matter, and contrast their properties with those of similar cascades of gluon radiation in vacuum. We argue that such cascades belong to two distinct classes that are characterized respectively by an increasing or a constant (or decreasing) branching rate along the cascade. In the former class, of which the BDMPS, medium-induced, cascade constitutes a typical example, it takes a finite time to transport a finite amount of energy to very soft quanta, while this time is essentially infinite in the latter case, to which the DGLAP cascade belongs. The medium induced cascade is accompanied by a constant flow of energy towards arbitrary soft modes, leading eventually to the accumulation of the initial energy of the leading particle at zero energy. It also exhibits scaling properties akin to wave turbulence. These properties do not show up in the cascade that develops in vacuum. There, the energy accumulates in the spectrum at smaller and smaller energy as the cascade develops, but the energy never flows all the way down to zero energy. Our analysis suggests that the way the energy is shared among the offsprings of a splitting gluon has little impact on the qualitative properties of the cascades, provided the kernel that governs the splittings is not too singular.

  13. Sulphur-impregnated flow cathode to enable high-energy-density lithium flow batteries

    NASA Astrophysics Data System (ADS)

    Chen, Hongning; Zou, Qingli; Liang, Zhuojian; Liu, Hao; Li, Quan; Lu, Yi-Chun

    2015-01-01

    Redox flow batteries are promising technologies for large-scale electricity storage, but have been suffering from low energy density and low volumetric capacity. Here we report a flow cathode that exploits highly concentrated sulphur-impregnated carbon composite, to achieve a catholyte volumetric capacity 294 Ah l-1 with long cycle life (>100 cycles), high columbic efficiency (>90%, 100 cycles) and high energy efficiency (>80%, 100 cycles). The demonstrated catholyte volumetric capacity is five times higher than the all-vanadium flow batteries (60 Ah l-1) and 3-6 times higher than the demonstrated lithium-polysulphide approaches (50-117 Ah l-1). Pseudo-in situ impedance and microscopy characterizations reveal superior electrochemical and morphological reversibility of the sulphur redox reactions. Our approach of exploiting sulphur-impregnated carbon composite in the flow cathode creates effective interfaces between the insulating sulphur and conductive carbon-percolating network and offers a promising direction to develop high-energy-density flow batteries.

  14. Dark energy and the quietness of the local Hubble flow

    NASA Astrophysics Data System (ADS)

    Axenides, M.; Perivolaropoulos, L.

    2002-06-01

    The linearity and quietness of the local (<10 Mpc) Hubble flow (LHF) in view of the very clumpy local universe is a long standing puzzle in standard and in open CDM (cold dark matter) cosmogony. The question addressed in this paper is whether the antigravity component of the recently discovered dark energy can cool the velocity flow enough to provide a solution to this puzzle. We calculate the growth of matter fluctuations in a flat universe containing a fraction ΩX(t0) of dark energy obeying the time independent equation of state pX=wρX. We find that dark energy can indeed cool the LHF. However the dark energy parameter values required to make the predicted velocity dispersion consistent with the observed value vrms~=40 km/s have been ruled out by other observational tests constraining the dark energy parameters w and ΩX. Therefore despite the claims of recent qualitative studies, dark energy with time independent equation of state cannot by itself explain the quietness and linearity of the local Hubble flow.

  15. Neutron radigoraphy of fluid flow for geothermal energy research

    SciTech Connect

    Bingham, Philip R.; Polsky, Yarom; Anovitz, L.; Carmichael, Justin R.; Bilheux, Hassina Z; Jacobson, David; Hussey, Dan

    2015-01-01

    Enhanced geothermal systems seek to expand the potential for geothermal energy by engineering heat exchange systems within the earth. A neutron radiography imaging method has been developed for the study of fluid flow through rock under environmental conditions found in enhanced geothermal energy systems. For this method, a pressure vessel suitable for neutron radiography was designed and fabricated, modifications to imaging instrument setups were tested, multiple contrast agents were tested, and algorithms developed for tracking of flow. The method has shown success for tracking of single phase flow through a manufactured crack in a 3.81 cm (1.5 inch) diameter core within a pressure vessel capable of confinement up to 69 MPa (10,000 psi) using a particle tracking approach with bubbles of fluorocarbon-based fluid as the “particles” and imaging with 10 ms exposures.

  16. Fully localised nonlinear energy growth optimals in pipe flow

    NASA Astrophysics Data System (ADS)

    Pringle, Chris C. T.; Willis, Ashley P.; Kerswell, Rich R.

    2015-06-01

    A new, fully localised, energy growth optimal is found over large times and in long pipe domains at a given mass flow rate. This optimal emerges at a threshold disturbance energy below which a nonlinear version of the known (streamwise-independent) linear optimal [P. J. Schmid and D. S. Henningson, "Optimal energy density growth in Hagen-Poiseuille flow," J. Fluid Mech. 277, 192-225 (1994)] is selected and appears to remain the optimal up until the critical energy at which transition is triggered. The form of this optimal is similar to that found in short pipes [Pringle et al., "Minimal seeds for shear flow turbulence: Using nonlinear transient growth to touch the edge of chaos," J. Fluid Mech. 702, 415-443 (2012)], but now with full localisation in the streamwise direction. This fully localised optimal perturbation represents the best approximation yet of the minimal seed (the smallest perturbation which is arbitrarily close to states capable of triggering a turbulent episode) for "real" (laboratory) pipe flows. Dependence of the optimal with respect to several parameters has been computed and establishes that the structure is robust.

  17. Fully localised nonlinear energy growth optimals in pipe flow

    SciTech Connect

    Pringle, Chris C. T.; Willis, Ashley P.; Kerswell, Rich R.

    2015-06-15

    A new, fully localised, energy growth optimal is found over large times and in long pipe domains at a given mass flow rate. This optimal emerges at a threshold disturbance energy below which a nonlinear version of the known (streamwise-independent) linear optimal [P. J. Schmid and D. S. Henningson, “Optimal energy density growth in Hagen-Poiseuille flow,” J. Fluid Mech. 277, 192–225 (1994)] is selected and appears to remain the optimal up until the critical energy at which transition is triggered. The form of this optimal is similar to that found in short pipes [Pringle et al., “Minimal seeds for shear flow turbulence: Using nonlinear transient growth to touch the edge of chaos,” J. Fluid Mech. 702, 415–443 (2012)], but now with full localisation in the streamwise direction. This fully localised optimal perturbation represents the best approximation yet of the minimal seed (the smallest perturbation which is arbitrarily close to states capable of triggering a turbulent episode) for “real” (laboratory) pipe flows. Dependence of the optimal with respect to several parameters has been computed and establishes that the structure is robust.

  18. Periodic flow at airway bifurcations. III. Energy dissipation.

    PubMed

    Tsuda, A; Savilonis, B J; Kamm, R D; Fredberg, J J

    1990-08-01

    We measured the energy dissipation associated with large-amplitude periodic flow through airway bifurcation models. Each model consisted of a single asymmetric bifurcation with a different branching angle and area ratio, with each branch terminated into an identical elastic load. Sinusoidal volumetric oscillations were applied at the parent duct so that the upstream Reynolds number (Re) varied from 30 to 77,000 and the Womersley parameter (alpha) from 4 to 30. Pressures were measured continuously at the parent duct and at both terminals, and instantaneous branch flow rates were calculated. Time-averaged energy dissipation in the bifurcation was computed from an energy budget over a control volume integrated over a cycle and was expressed as a friction factor, F. We found that when tidal volume was small [ratio of tidal volume to resident (dead space) volume, VT/VD less than 1], F was independent of branching angle and fell with increasing alpha and VT/VD. When tidal volume was large (VT/VD greater than 1), F increased with increasing branching angle and varied less strongly with alpha and VT/VD. No simple benchmark flow represented the data well over the entire experimental range. This study demonstrates that only two nondimensional parameters, alpha and VT/VD, are necessary and are sufficient to describe time-averaged energy dissipation in a given bifurcation geometry during sinusoidal flow.

  19. Annual energy status report, 1981. Ohio energy flow chart

    SciTech Connect

    Not Available

    1982-01-01

    There will be no foreseeable shortage of conventional fuels in Ohio during the coming decade. There is a discussion of various projections on a national, as well as a state-wide, basis for energy demand through the year 1990. Fuel prices will continue to escalate. Perhaps not at the rate experienced during the 1970's, but increased fuel prices will occur. This will result in a demand-side constraint, either through active (insulation) or passive (thermostat setback) measures. We have seen that the conservation ethic in Ohio has had a significant effect on consumption. Ohioans reduced their consumption by 313 trillion Btu's between 1979 and 1980. A recent audit by US DOE credits ODOE programs with a net savings of at least 66 trillion Btu's, with additional probable savings of 54 trillion Btu's. A conservative estimate of Ohio energy prices of $3.00 per million Btu's thus indicates that the Department efforts saved Ohio consumers between $200 and $330 million during 1980. These savings are attributed to the State Energy Conservation Plan (SECP). The remaining energy savings accrued from a combination of the recession which had an effect on industrial and individual energy consumption, plus cost-avoidance by the consumer in their active and passive conservation efforts.

  20. Pulsatile blood flow, shear force, energy dissipation and Murray's Law

    PubMed Central

    Painter, Page R; Edén, Patrik; Bengtsson, Hans-Uno

    2006-01-01

    Background Murray's Law states that, when a parent blood vessel branches into daughter vessels, the cube of the radius of the parent vessel is equal to the sum of the cubes of the radii of daughter blood vessels. Murray derived this law by defining a cost function that is the sum of the energy cost of the blood in a vessel and the energy cost of pumping blood through the vessel. The cost is minimized when vessel radii are consistent with Murray's Law. This law has also been derived from the hypothesis that the shear force of moving blood on the inner walls of vessels is constant throughout the vascular system. However, this derivation, like Murray's earlier derivation, is based on the assumption of constant blood flow. Methods To determine the implications of the constant shear force hypothesis and to extend Murray's energy cost minimization to the pulsatile arterial system, a model of pulsatile flow in an elastic tube is analyzed. A new and exact solution for flow velocity, blood flow rate and shear force is derived. Results For medium and small arteries with pulsatile flow, Murray's energy minimization leads to Murray's Law. Furthermore, the hypothesis that the maximum shear force during the cycle of pulsatile flow is constant throughout the arterial system implies that Murray's Law is approximately true. The approximation is good for all but the largest vessels (aorta and its major branches) of the arterial system. Conclusion A cellular mechanism that senses shear force at the inner wall of a blood vessel and triggers remodeling that increases the circumference of the wall when a shear force threshold is exceeded would result in the observed scaling of vessel radii described by Murray's Law. PMID:16923189

  1. Technology data characterizing refrigeration in commercial buildings: Application to end-use forecasting with COMMEND 4.0

    SciTech Connect

    Sezgen, O.; Koomey, J.G.

    1995-12-01

    In the United States, energy consumption is increasing most rapidly in the commercial sector. Consequently, the commercial sector is becoming an increasingly important target for state and federal energy policies and also for utility-sponsored demand side management (DSM) programs. The rapid growth in commercial-sector energy consumption also makes it important for analysts working on energy policy and DSM issues to have access to energy end-use forecasting models that include more detailed representations of energy-using technologies in the commercial sector. These new forecasting models disaggregate energy consumption not only by fuel type, end use, and building type, but also by specific technology. The disaggregation of the refrigeration end use in terms of specific technologies, however, is complicated by several factors. First, the number of configurations of refrigeration cases and systems is quite large. Also, energy use is a complex function of the refrigeration-case properties and the refrigeration-system properties. The Electric Power Research Institute`s (EPRI`s) Commercial End-Use Planning System (COMMEND 4.0) and the associated data development presented in this report attempt to address the above complications and create a consistent forecasting framework. Expanding end-use forecasting models so that they address individual technology options requires characterization of the present floorstock in terms of service requirements, energy technologies used, and cost-efficiency attributes of the energy technologies that consumers may choose for new buildings and retrofits. This report describes the process by which we collected refrigeration technology data. The data were generated for COMMEND 4.0 but are also generally applicable to other end-use forecasting frameworks for the commercial sector.

  2. Effects of Regulation and Technology on End Uses of Nonfuel Mineral Commodities in the United States

    USGS Publications Warehouse

    Matos, Grecia R.

    2007-01-01

    The regulatory system and advancement of technologies have shaped the end-use patterns of nonfuel minerals used in the United States. These factors affected the quantities and types of materials used by society. Environmental concerns and awareness of possible negative effects on public health prompted numerous regulations that have dramatically altered the use of commodities like arsenic, asbestos, lead, and mercury. While the selected commodities represent only a small portion of overall U.S. materials use, they have the potential for harmful effects on human health or the environment, which other commodities, like construction aggregates, do not normally have. The advancement of technology allowed for new uses of mineral materials in products like high-performance computers, telecommunications equipment, plasma and liquid-crystal display televisions and computer monitors, mobile telephones, and electronic devices, which have become mainstream products. These technologies altered the end-use pattern of mineral commodities like gallium, germanium, indium, and strontium. Human ingenuity and people?s demand for different and creative services increase the demand for new materials and industries while shifting the pattern of use of mineral commodities. The mineral commodities? end-use data are critical for the understanding of the magnitude and character of these flows, assessing their impact on the environment, and providing an early warning of potential problems in waste management of products containing these commodities. The knowledge of final disposition of the mineral commodity allows better decisions as to how regulation should be tailored.

  3. Nematomorph parasites drive energy flow through a riparian ecosystem

    USGS Publications Warehouse

    Sato, Takuya; Wtanabe, Katsutoshi; Kanaiwa, Minoru; Niizuma, Yasuaki; Harada, Yasushi; Lafferty, Kevin D.

    2011-01-01

    Parasites are ubiquitous in natural systems and ecosystem-level effects should be proportional to the amount of biomass or energy flow altered by the parasites. Here we quantified the extent to which a manipulative parasite altered the flow of energy through a forest-stream ecosystem. In a Japanese headwater stream, camel crickets and grasshoppers (Orthoptera) were 20 times more likely to enter a stream if infected by a nematomorph parasite (Gordionus spp.), corroborating evidence that nematomorphs manipulate their hosts to seek water where the parasites emerge as free-living adults. Endangered Japanese trout (Salvelinus leucomaenis japonicus) readily ate these infected orthopterans, which due to their abundance, accounted for 60% of the annual energy intake of the trout population. Trout grew fastest in the fall, when nematomorphs were driving energy-rich orthopterans into the stream. When infected orthopterans were available, trout did not eat benthic invertebrates in proportion to their abundance, leading to the potential for cascading, indirect effects through the forest-stream ecosystem. These results provide the first quantitative evidence that a manipulative parasite can dramatically alter the flow of energy through and across ecosystems.

  4. Structural modelling of a compliant flexure flow energy harvester

    NASA Astrophysics Data System (ADS)

    Chatterjee, Punnag; Bryant, Matthew

    2015-09-01

    This paper presents the concept of a flow-induced vibration energy harvester based on a one-piece compliant flexure structure. This energy harvester utilizes the aeroelastic flutter phenomenon to convert flow energy to structural vibrational energy and to electrical power output through piezoelectric transducers. This flexure creates a discontinuity in the structural stiffness and geometry that can be used to tailor the mode shapes and natural frequencies of the device to the desired operating flow regime while eliminating the need for discrete hinges that are subject to fouling and friction. An approximate representation of the flexure rigidity is developed from the flexure link geometry, and a model of the complete discontinuous structure and integrated flexure is formulated based on the transfer matrix method. The natural frequencies and mode shapes predicted by the model are validated using finite element simulations and are shown to be in close agreement. A proof-of-concept energy harvester incorporating the proposed flexure design has been fabricated and investigated in wind tunnel testing. The aeroelastic modal convergence, critical flutter wind speed, power output and limit cycle behavior of this device is experimentally determined and discussed.

  5. Viscous Energy Loss in the Presence of Abnormal Aortic Flow

    PubMed Central

    Barker, A.J.; van Ooij, P.; Bandi, K.; Garcia, J.; Albaghdadi, M.; McCarthy, P.; Bonow, R. O.; Carr, J.; Collins, J.; Malaisrie, C.; Markl, M.

    2014-01-01

    Purpose To present a theoretical basis for noninvasively characterizing in vivo fluid-mechanical energy losses, and to apply it in a pilot study of patients known to express abnormal aortic flow patterns. Methods 4D flow MRI was used to characterize laminar viscous energy losses in the aorta of normal controls (n=12, age=37±10), patients with aortic dilation (n=16, age=52±8), and patients with aortic valve stenosis matched for age and aortic size (n=14, age=46±15), using a relationship between the 3D velocity field and viscous energy dissipation. Results Viscous energy loss was significantly elevated in the thoracic aorta for patients with dilated aorta (3.6±1.3 mW, p=0.024) and patients with aortic stenosis (14.3±8.2 mW, p<0.001) compared to healthy volunteers (2.3±0.9 mW). The same pattern of significant differences were seen in the ascending aorta, where viscous energy losses in patients with dilated aortas (2.2±1.1 mW, p=0.021) and patients with aortic stenosis (10.9±6.8 mW, p<0.001) were elevated compared to healthy volunteers (1.2±0.6 mW). Conclusion This technique provides a capability to quantify the contribution of abnormal laminar blood flow to increased ventricular afterload. In this pilot study, viscous energy loss in patient cohorts was significantly elevated and indicates that cardiac afterload is increased due to abnormal flow. PMID:24122967

  6. Soap film flow visualization investigations of oscillating wing energy harvesters

    NASA Astrophysics Data System (ADS)

    Kirschmeier, Benjamin; Bryant, Matthew

    2015-03-01

    With increasing population and proliferation of wireless electronics, significant research attention has turned to harvesting energy from ambient sources such as wind and water flows at scales ranging from micro-watt to mega-watt levels. One technique that has recently attracted attention is the application of bio-inspired flapping wings for energy harvesting. This type of system uses a heaving and pitching airfoil to extract flow energy and generate electricity. Such a device can be realized using passive devices excited by aeroelastic flutter phenomena, kinematic mechanisms driven by mechanical linkages, or semi-active devices that are actively controlled in one degree of freedom and passively driven in another. For these types of systems, numerical simulations have showed strong dependence on efficiency and vortex interaction. In this paper we propose a new apparatus for reproducing arbitrary pitch-heave waveforms to perform flow visualization experiments in a soap film tunnel. The vertically falling, gravity driven soap film tunnel is used to replicate flows with a chord Reynolds number on the order of 4x104. The soap film tunnel is used to investigate leading edge vortex (LEV) and trailing edge vortex (TEV) interactions for sinusoidal and non-sinusoidal waveforms. From a qualitative analysis of the fluid structure interaction, we have been able to demonstrate that the LEVs for non-sinusoidal motion convect faster over the airfoil compared with sinusoidal motion. Signifying that optimal flapping frequency is dependent on the motion profile.

  7. High energy sodium based room temperature flow batteries

    NASA Astrophysics Data System (ADS)

    Shamie, Jack

    As novel energy sources such as solar, wind and tidal energies are explored it becomes necessary to build energy storage facilities to load level the intermittent nature of these energy sources. Energy storage is achieved by converting electrical energy into another form of energy. Batteries have many properties that are attractive for energy storage including high energy and power. Among many different types of batteries, redox flow batteries (RFBs) offer many advantages. Unlike conventional batteries, RFBs store energy in a liquid medium rather than solid active materials. This method of storage allows for the separation of energy and power unlike conventional batteries. Additionally flow batteries may have long lifetimes because there is no expansion or contraction of electrodes. A major disadvantage of RFB's is its lower energy density when compared to traditional batteries. In this Thesis, a novel hybrid Na-based redox flow battery (HNFB) is explored, which utilizes a room temperature molten sodium based anode, a sodium ion conducting solid electrolyte and liquid catholytes. The sodium electrode leads to high voltages and energy and allows for the possibility of multi-electron transfer per molecule. Vanadium acetylacetonate (acac) and TEMPO have been investigated for their use as catholytes. In the vanadium system, 2 electrons transfers per vanadium atom were found leading to a doubling of capacity. In addition, degradation of the charged state was found to be reversible within the voltage range of the cell. Contamination by water leads to the formation of vanadyl acetylacetonate. Although it is believed that vanadyl complex need to be taken to low voltages to be reduced back to vanadium acac, a new mechanism is shown that begins at higher voltages (2.1V). Vanadyl complexes react with excess ligand and protons to reform the vanadium complex. During this reaction, water is reformed leading to the continuous cycle in which vanadyl is formed and then reduced back

  8. High energy density Z-pinch plasmas using flow stabilization

    SciTech Connect

    Shumlak, U. Golingo, R. P. Nelson, B. A. Bowers, C. A. Doty, S. A. Forbes, E. G. Hughes, M. C. Kim, B. Knecht, S. D. Lambert, K. K. Lowrie, W. Ross, M. P. Weed, J. R.

    2014-12-15

    The ZaP Flow Z-Pinch research project[1] at the University of Washington investigates the effect of sheared flows on MHD instabilities. Axially flowing Z-pinch plasmas are produced that are 100 cm long with a 1 cm radius. The plasma remains quiescent for many radial Alfvén times and axial flow times. The quiescent periods are characterized by low magnetic mode activity measured at several locations along the plasma column and by stationary visible plasma emission. Plasma evolution is modeled with high-resolution simulation codes – Mach2, WARPX, NIMROD, and HiFi. Plasma flow profiles are experimentally measured with a multi-chord ion Doppler spectrometer. A sheared flow profile is observed to be coincident with the quiescent period, and is consistent with classical plasma viscosity. Equilibrium is determined by diagnostic measurements: interferometry for density; spectroscopy for ion temperature, plasma flow, and density[2]; Thomson scattering for electron temperature; Zeeman splitting for internal magnetic field measurements[3]; and fast framing photography for global structure. Wall stabilization has been investigated computationally and experimentally by removing 70% of the surrounding conducting wall to demonstrate no change in stability behavior.[4] Experimental evidence suggests that the plasma lifetime is only limited by plasma supply and current waveform. The flow Z-pinch concept provides an approach to achieve high energy density plasmas,[5] which are large, easy to diagnose, and persist for extended durations. A new experiment, ZaP-HD, has been built to investigate this approach by separating the flow Z-pinch formation from the radial compression using a triaxial-electrode configuration. This innovation allows more detailed investigations of the sheared flow stabilizing effect, and it allows compression to much higher densities than previously achieved on ZaP by reducing the linear density and increasing the pinch current. Experimental results and

  9. The Electrochemical Flow Capacitor: Capacitive Energy Storage in Flowable Media

    NASA Astrophysics Data System (ADS)

    Dennison, Christopher R.

    Electrical energy storage (EES) has emerged as a necessary aspect of grid infrastructure to address the increasing problem of grid instability imposed by the large scale implementation of renewable energy sources (such as wind or solar) on the grid. Rapid energy recovery and storage is critically important to enable immediate and continuous utilization of these resources, and provides other benefits to grid operators and consumers as well. In past decades, there has been significant progress in the development of electrochemical EES technologies which has had an immense impact on the consumer and micro-electronics industries. However, these advances primarily address small-scale storage, and are often not practical at the grid-scale. A new energy storage concept called "the electrochemical flow capacitor (EFC)" has been developed at Drexel which has significant potential to be an attractive technology for grid-scale energy storage. This new concept exploits the characteristics of both supercapacitors and flow batteries, potentially enabling fast response rates with high power density, high efficiency, and long cycle lifetime, while decoupling energy storage from power output (i.e., scalable energy storage capacity). The unique aspect of this concept is the use of flowable carbon-electrolyte slurry ("flowable electrode") as the active material for capacitive energy storage. This dissertation work seeks to lay the scientific groundwork necessary to develop this new concept into a practical technology, and to test the overarching hypothesis that energy can be capacitively stored and recovered from a flowable media. In line with these goals, the objectives of this Ph.D. work are to: i) perform an exploratory investigation of the operating principles and demonstrate the technical viability of this new concept and ii) establish a scientific framework to assess the key linkages between slurry composition, flow cell design, operating conditions and system performance. To

  10. Heat transfer and flow in solar energy and bioenergy systems

    NASA Astrophysics Data System (ADS)

    Xu, Ben

    The demand for clean and environmentally benign energy resources has been a great concern in the last two decades. To alleviate the associated environmental problems, reduction of the use of fossil fuels by developing more cost-effective renewable energy technologies becomes more and more significant. Among various types of renewable energy sources, solar energy and bioenergy take a great proportion. This dissertation focuses on the heat transfer and flow in solar energy and bioenergy systems, specifically for Thermal Energy Storage (TES) systems in Concentrated Solar Power (CSP) plants and open-channel algal culture raceways for biofuel production. The first part of this dissertation is the discussion about mathematical modeling, numerical simulation and experimental investigation of solar TES system. First of all, in order to accurately and efficiently simulate the conjugate heat transfer between Heat Transfer Fluid (HTF) and filler material in four different solid-fluid TES configurations, formulas of an e?ective heat transfer coe?cient were theoretically developed and presented by extending the validity of Lumped Capacitance Method (LCM) to large Biot number, as well as verifications/validations to this simplified model. Secondly, to provide design guidelines for TES system in CSP plant using Phase Change Materials (PCM), a general storage tank volume sizing strategy and an energy storage startup strategy were proposed using the enthalpy-based 1D transient model. Then experimental investigations were conducted to explore a novel thermal storage material. The thermal storage performances were also compared between this novel storage material and concrete at a temperature range from 400 °C to 500 °C. It is recommended to apply this novel thermal storage material to replace concrete at high operating temperatures in sensible heat TES systems. The second part of this dissertation mainly focuses on the numerical and experimental study of an open-channel algae

  11. Evaluation of CO2 Emissions from End-use Heat and Power Supplying Systems

    NASA Astrophysics Data System (ADS)

    Kiho, Mariko; Endo, Yasuyuki; Ito, Akito

    It is required for the energy systems to satisfy simultaneous solutions to the problems, such as cost reduction, global warming, assurance of energy security, and resource conservation. To evaluate optimal end-use energy systems from the stand point of CO2 emissions, we apply a comprehensive approach based on the life cycle assessment. Several combinations of electricity and heat supplying systems are compared. They include the electricity driven heat pump, gas engine co-generation, absorption refrigeration and so on. Calculations represent total CO2 emission by energy consumption of several operation patterns, based on the actual data of energy demand, CO2 intensity of the grid electricity and the equipment specifications. The results indicate that CO2 emissions can be minimized by maximum utilization of electricity from the grid.

  12. End-Use Load and Consumer Assessment Program: Characterizing residential thermal performance from high resolution end-use data

    SciTech Connect

    Miller, N.E.; Williamson, M.A.; Bailey, S.A.; Pratt, R.G.; Stokes, G.M.; Sandusky, W.F.; Pearson, E.W.; Roberts, J.S.

    1991-06-01

    This document is part of a two-volume set describing a series of thermal analyses of the residential buildings monitored under the End-Use Load and Consumer Assessment Program. Volume 1 describes in detail the thermal analysis methodology employed. Volume 2 presents the results of applying the methodology in a series of four distinct analyses: (1) an analysis of the first monitored heating season, 1985--1986; (2) an analysis of the second monitored heating season, (3) a comparison of first- and second-year analyses showing changes in residential consumption with changes in weather and evaluating the ability of the analytical technique to discriminate those changes; and (4) a continuation of the previous analyses evaluating the effects of foundation type and heating system type on the results.

  13. Lithium-Based High Energy Density Flow Batteries

    NASA Technical Reports Server (NTRS)

    Bugga, Ratnakumar V. (Inventor); West, William C. (Inventor); Kindler, Andrew (Inventor); Smart, Marshall C. (Inventor)

    2014-01-01

    Systems and methods in accordance with embodiments of the invention implement a lithium-based high energy density flow battery. In one embodiment, a lithium-based high energy density flow battery includes a first anodic conductive solution that includes a lithium polyaromatic hydrocarbon complex dissolved in a solvent, a second cathodic conductive solution that includes a cathodic complex dissolved in a solvent, a solid lithium ion conductor disposed so as to separate the first solution from the second solution, such that the first conductive solution, the second conductive solution, and the solid lithium ionic conductor define a circuit, where when the circuit is closed, lithium from the lithium polyaromatic hydrocarbon complex in the first conductive solution dissociates from the lithium polyaromatic hydrocarbon complex, migrates through the solid lithium ionic conductor, and associates with the cathodic complex of the second conductive solution, and a current is generated.

  14. Flow Structures and Energy Capture from an Oscillating Hydrofoil

    NASA Astrophysics Data System (ADS)

    Franck, Jennifer; Frank, Sarah; Mandre, Shreyas

    2013-11-01

    The flow surrounding an oscillating hydrofoil in a uniform freestream is computationally investigated for hydrokinetic energy capture. Simulations are performed on an elliptical hydrofoil using 2D Direct Numerical Simulation (DNS) for low Reynolds number and 3D Large-Eddy Simulations (LES) for high Reynolds number simulations at 80,000. A non-inertial reference frame is utilized for rigid-body motion of the hydrofoil, which is prescribed a sinusoidal motion in pitch and heave. The kinematic parameters are varied and the resulting flow features are correlated with positive or negative energy capture. In an effort to optimize the stroke, variations in the sinusoidal heave and pitch signals are systematically explored and analyzed for future closed-loop control.

  15. Uncovering the end uses of the rare earth elements.

    PubMed

    Du, Xiaoyue; Graedel, T E

    2013-09-01

    The rare earth elements (REE) are a group of fifteen elements with unique properties that make them indispensable for a wide variety of emerging and conventional established technologies. However, quantitative knowledge of REE remains sparse, despite the current heightened interest in future availability of the resources. Mining is heavily concentrated in China, whose monopoly position and potential restriction of exports render primary supply vulnerable to short term disruption. We have drawn upon the published literature and unpublished materials in different languages to derive the first quantitative annual domestic production by end use of individual rare earth elements from 1995 to 2007. The information is illustrated in Sankey diagrams for the years 1995 and 2007. Other years are available in the supporting information. Comparing 1995 and 2007, the production of the rare earth elements in China, Japan, and the US changed dramatically in quantities and structure. The information can provide a solid foundation for industries, academic institutions and governments to make decisions and develop strategies.

  16. Model estimation of energy flow in Oregon coastal seabird populations

    USGS Publications Warehouse

    Wiens, J.A.; Scott, J.M.

    1976-01-01

    A computer simulation model was used to explore the patterns and magnitudes of population density changes and population energy demands in Oregon populations of Sooty Shear-waters, Leach?s Storm-Petrels, Brandt?s Cormorants, and Common Murres. The species differ in seasonal distribution and abundance, with shearwaters attaining high densities during their migratory movements through Oregon waters, and murres exhibiting the greatest seasonal stability in population numbers. On a unit area basis, annual energy flow is greatest through murre and cormorant populations. However, because shearwaters occupy a larger area during their transit, they dominate the total energy flow through the four-species seabird ?community.?.....Consumption of various prey types is estimated by coupling model output of energy demands with information on dietary habits. This analysis suggests that murres annually consume nearly twice as many herring as any other prey and consume approximately equal quantities of anchovy, smelt, cod, and rockfish. Cormorants consume a relatively small quantity of bottom-dwelling fish, while stormpetrels take roughly equal quantities of euphausiids and hydrozoans. Anchovies account for 43% of the 62,506 metric tons of prey the four species are estimated to consume annually; 86% of this anchovy consumption is by shearwaters. The consumption of pelagic fishes by these four populations within the neritic zone may represent as much as 22% of the annual production of these fish.

  17. Energy-decomposition analysis for viscous free-surface flows.

    PubMed

    Colagrossi, Andrea; Bouscasse, Benjamin; Marrone, Salvatore

    2015-11-01

    This work is dedicated to the energy decomposition analysis of a viscous free-surface flow. In the presence of a free surface, the viscous dissipation for a Newtonian liquid can be decomposed into two terms: an enstrophy component and a free-surface deformation component. The latter requires the evaluation of volume and surface integrals in the meshless framework. The analysis is based on the weakly compressible smoothed particle hydrodynamics formalism. The behavior of the energy terms is studied in standing wave problems by changing the viscosity and the wave amplitude. Finally, an analysis of a complex shallow water breaking wave case is provided. It is shown that in presence of intense breaking phenomena the two energy components are always comparable, whereas generally the free surface component is dominant on the viscous dissipation of gravity waves. PMID:26651775

  18. Energy-decomposition analysis for viscous free-surface flows

    NASA Astrophysics Data System (ADS)

    Colagrossi, Andrea; Bouscasse, Benjamin; Marrone, Salvatore

    2015-11-01

    This work is dedicated to the energy decomposition analysis of a viscous free-surface flow. In the presence of a free surface, the viscous dissipation for a Newtonian liquid can be decomposed into two terms: an enstrophy component and a free-surface deformation component. The latter requires the evaluation of volume and surface integrals in the meshless framework. The analysis is based on the weakly compressible smoothed particle hydrodynamics formalism. The behavior of the energy terms is studied in standing wave problems by changing the viscosity and the wave amplitude. Finally, an analysis of a complex shallow water breaking wave case is provided. It is shown that in presence of intense breaking phenomena the two energy components are always comparable, whereas generally the free surface component is dominant on the viscous dissipation of gravity waves.

  19. Energy flow characteristics of vector X-Waves.

    PubMed

    Salem, Mohamed A; Bağcı, Hakan

    2011-04-25

    The vector form of X-Waves is obtained as a superposition of transverse electric and transverse magnetic polarized field components. It is shown that the signs of all components of the Poynting vector can be locally changed using carefully chosen complex amplitudes of the transverse electric and transverse magnetic polarization components. Negative energy flux density in the longitudinal direction can be observed in a bounded region around the centroid; in this region the local behavior of the wave field is similar to that of wave field with negative energy flow. This peculiar energy flux phenomenon is of essential importance for electromagnetic and optical traps and tweezers, where the location and momenta of micro-and nanoparticles are manipulated by changing the Poynting vector, and in detection of invisibility cloaks.

  20. Turbulent kinetic energy production and flow structures in compressible homogeneous shear flow

    NASA Astrophysics Data System (ADS)

    Ma, Zongqiang; Xiao, Zuoli

    2016-09-01

    The production of turbulent kinetic energy (TKE) and flow structures in compressible homogeneous turbulent shear flow (HTSF) are investigated by using direct numerical simulation. A theoretical analysis suggests that the vertical turbulent transport process should be responsible for the production of TKE in HTSF. It is manifested based on a conditional average method that the pure TKE production becomes increasingly larger in strain regions than in vortex regions of the flow. The velocity-derivative correlation in the shear plane is employed to identify the streaky structures in HTSF, which also tend to occur predominantly in strain regions of turbulence. Localized analyses of conditional averages reveal that the streaky structures in compressible HTSF are closely related to the negative productions of TKE. A comparative study implies that flow compressibility has a considerable effect on the spatial distributions and patterns of the strain- and vortex-dominated fields, which in turn cause the discrepancies in distribution of the TKE production and streaky structures between incompressible and compressible HTSFs.

  1. Resource acquisition, distribution and end-use efficiencies and the growth of industrial society

    NASA Astrophysics Data System (ADS)

    Jarvis, A. J.; Jarvis, S. J.; Hewitt, C. N.

    2015-10-01

    A key feature of the growth of industrial society is the acquisition of increasing quantities of resources from the environment and their distribution for end-use. With respect to energy, the growth of industrial society appears to have been near-exponential for the last 160 years. We provide evidence that indicates that the global distribution of resources that underpins this growth may be facilitated by the continual development and expansion of near-optimal directed networks (roads, railways, flight paths, pipelines, cables etc.). However, despite this continual striving for optimisation, the distribution efficiencies of these networks must decline over time as they expand due to path lengths becoming longer and more tortuous. Therefore, to maintain long-term exponential growth the physical limits placed on the distribution networks appear to be counteracted by innovations deployed elsewhere in the system, namely at the points of acquisition and end-use of resources. We postulate that the maintenance of the growth of industrial society, as measured by global energy use, at the observed rate of ~ 2.4 % yr-1 stems from an implicit desire to optimise patterns of energy use over human working lifetimes.

  2. Towards Engineered Energy Flows in Quantum Dot Assemblies

    NASA Astrophysics Data System (ADS)

    Crooker, Scott A.

    2003-03-01

    Communication, coupling, and coherence between quantum dots are central themes in numerous scientific efforts of present physical and technological interest. In the limit of large numbers of coupled dots, colloidal semiconductor nanocrystal quantum dots (NQDs) are promising building blocks for the bottom-up assembly of macroscopic Â"artificial materialsÂ" having engineered functionality. Although NQDs offer size-tunable optical properties and ease of chemical manipulation into structures of varied complexity, strong inter-dot coupling (e.g., via electron tunneling) requires close proximity and a high degree of structural order, conditions which are difficult to achieve in practice. In this work [1] we investigate an alternative approach involving NQD coupling via long-range dipolar interactions, which allow inter-dot communication via resonant (Förster) energy transfer. We present studies of the dynamics of resonant energy transfer in monodisperse, mixed-size, and energy gradient (layered) assemblies of CdSe NQDs. Time- and spectrally-resolved photoluminescence data directly reveal the energy-dependent transfer rate of excitons from smaller to larger dots, showing sub-nanosecond energy transfer directly across a large tens-of-meV energy gap (i.e., between dots of disparate size). Results from layered NQD assemblies demonstrate unidirectional energy flows, a first step towards artificial light-harvesting structures. In comparison with some of Nature's most efficient energy transfer complexes -- chlorophylls -- the data suggest that inter-dot energy transfer can approach picosecond time scales in structurally optimized systems. [1] S. A. Crooker, J. A. Hollingsworth, S. Tretiak, and V. I. Klimov, Phys. Rev. Lett. v89, p186802 (2002).

  3. Constructive interference in arrays of energy harvesters in fluid flows

    NASA Astrophysics Data System (ADS)

    Azadeh Ranjbar, Vahid; Goushcha, Oleg; Elvin, Niell; Andreopoulos, Yiannis

    2014-11-01

    In the present work we demonstrate some unique opportunities which exist to increase the power harvested with fluidic piezoelectric generators by almost two orders of magnitude higher than existing methods by exploiting dynamic non-linearities and deploying multi-element arrays in carefully selected positions in a fluid flow field. These ac-coupled generators convert fluid kinetic energy, which otherwise would be wasted, into electrical energy. The available power in a flowing fluid is proportional to the cube of its velocity and if it is properly harvested can be used for continuously powering very small electronic devices or can be rectified and stored for intermittent use. Additional experimental work has shown that non-linear arrays of such energy harvesters can produce high output voltages in a very broadband range of frequencies. In our work, we investigate the effect of geometric parameters such as spatial arrangement and the mutual interference between the elements of a non-linear array on their overall performance and efficiency characteristics. Analytical tools based on the non-linear van der Pol oscillator have been also developed and verified with experimental data. Work supported by National Science Foundation under Grant No. CBET #1033117.

  4. An Energy Principle for Ideal MHD Equilibria with Flows

    SciTech Connect

    Yao Zhou and Hong Qin

    2013-03-11

    In the standard ideal MHD energy principle for equilibria with no flows, the stability criterion, which is the defi niteness of the perturbed potential energy, is usually constructed from the linearized equation of motion. Equivalently while more straightforwardly, it can also be obtained from the second variation of the Hamiltonian calculated with proper constraints. For equilibria with flows, a stability criterion was proposed from the linearized equation of motion, but not explained as an energy principle1. In this paper, the second variation of the Hamiltonian is found to provide a stability criterion equivalent to, while more straightforward than, what was constructed from the linearized equation of motion. To calculate the variations of the Hamiltonian, a complete set of constraints on the dynamics of the perturbations is derived from the Euler-Poincare structure of the ideal MHD. In addition, a previous calculation of the second variation of the Hamiltonian was claimed to give a different stability criterion2, and in this paper we argue such a claim is incorrect.

  5. Flow based vs. demand based energy-water modelling

    NASA Astrophysics Data System (ADS)

    Rozos, Evangelos; Nikolopoulos, Dionysis; Efstratiadis, Andreas; Koukouvinos, Antonios; Makropoulos, Christos

    2015-04-01

    The water flow in hydro-power generation systems is often used downstream to cover other type of demands like irrigation and water supply. However, the typical case is that the energy demand (operation of hydro-power plant) and the water demand do not coincide. Furthermore, the water inflow into a reservoir is a stochastic process. Things become more complicated if renewable resources (wind-turbines or photovoltaic panels) are included into the system. For this reason, the assessment and optimization of the operation of hydro-power systems are challenging tasks that require computer modelling. This modelling should not only simulate the water budget of the reservoirs and the energy production/consumption (pumped-storage), but should also take into account the constraints imposed by the natural or artificial water network using a flow routing algorithm. HYDRONOMEAS, for example, uses an elegant mathematical approach (digraph) to calculate the flow in a water network based on: the demands (input timeseries), the water availability (simulated) and the capacity of the transmission components (properties of channels, rivers, pipes, etc.). The input timeseries of demand should be estimated by another model and linked to the corresponding network nodes. A model that could be used to estimate these timeseries is UWOT. UWOT is a bottom up urban water cycle model that simulates the generation, aggregation and routing of water demand signals. In this study, we explore the potentials of UWOT in simulating the operation of complex hydrosystems that include energy generation. The evident advantage of this approach is the use of a single model instead of one for estimation of demands and another for the system simulation. An application of UWOT in a large scale system is attempted in mainland Greece in an area extending over 130×170 km². The challenges, the peculiarities and the advantages of this approach are examined and critically discussed.

  6. Variational energy principle for compressible, baroclinic flow. 2: Free-energy form of Hamilton's principle

    NASA Technical Reports Server (NTRS)

    Schmid, L. A.

    1977-01-01

    The first and second variations are calculated for the irreducible form of Hamilton's Principle that involves the minimum number of dependent variables necessary to describe the kinetmatics and thermodynamics of inviscid, compressible, baroclinic flow in a specified gravitational field. The form of the second variation shows that, in the neighborhood of a stationary point that corresponds to physically stable flow, the action integral is a complex saddle surface in parameter space. There exists a form of Hamilton's Principle for which a direct solution of a flow problem is possible. This second form is related to the first by a Friedrichs transformation of the thermodynamic variables. This introduces an extra dependent variable, but the first and second variations are shown to have direct physical significance, namely they are equal to the free energy of fluctuations about the equilibrium flow that satisfies the equations of motion. If this equilibrium flow is physically stable, and if a very weak second order integral constraint on the correlation between the fluctuations of otherwise independent variables is satisfied, then the second variation of the action integral for this free energy form of Hamilton's Principle is positive-definite, so the action integral is a minimum, and can serve as the basis for a direct trail and error solution. The second order integral constraint states that the unavailable energy must be maximum at equilibrium, i.e. the fluctuations must be so correlated as to produce a second order decrease in the total unavailable energy.

  7. The total flow concept for geothermal energy conversion

    NASA Technical Reports Server (NTRS)

    Austin, A. L.

    1974-01-01

    A geothermal development project has been initiated at the Lawrence Livermore Laboratory (LLL) to emphasize development of methods for recovery and conversion of the energy in geothermal deposits of hot brines. Temperatures of these waters vary from 150 C to more than 300 C with dissolved solids content ranging from less than 0.1% to over 25% by weight. Of particular interest are the deposits of high-temperature/high-salinity brines, as well as less saline brines, known to occur in the Salton Trough of California. Development of this resource will depend on resolution of the technical problems of brine handling, scale and precipitation control, and corrosion/erosion resistant systems for efficient conversion of thermal to electrical energy. Research experience to date has shown these problems to be severe. Hence, the LLL program emphasizes development of an entirely different approach called the Total Flow concept.

  8. Recent trends in energy flows through the Arctic climate system

    NASA Astrophysics Data System (ADS)

    Mayer, Michael; Haimberger, Leo

    2016-04-01

    While Arctic climate change can be diagnosed in many parameters, a comprehensive assessment of long-term changes and low frequency variability in the coupled Arctic energy budget still remains challenging due to the complex physical processes involved and the lack of observations. Here we draw on strongly improved observational capabilities of the past 15 years and employ observed radiative fluxes from CERES along with state-of-the-art atmospheric as well as coupled ocean-ice reanalyses to explore recent changes in energy flows through the Arctic climate system. Various estimates of ice volume and ocean heat content trends imply that the energy imbalance of the Arctic climate system was >1 Wm-2 during the 2000-2015 period, where most of the extra heat warmed the ocean and a comparatively small fraction was used to melt sea ice. The energy imbalance was partly fed by enhanced oceanic heat transports into the Arctic, especially in the mid 2000s. Seasonal trends of net radiation show a very clear signal of the ice-albedo feedback. Stronger radiative energy input during summer means increased seasonal oceanic heat uptake and accelerated sea ice melt. In return, lower minimum sea ice extent and higher SSTs lead to enhanced heat release from the ocean during fall season. These results are consistent with modeling studies finding an enhancement of the annual cycle of surface energy exchanges in a warming Arctic. Moreover, stronger heat fluxes from the ocean to the atmosphere in fall tend to warm the arctic boundary layer and reduce meridional temperature gradients, thereby reducing atmospheric energy transports into the polar cap. Although the observed results are a robust finding, extended high-quality datasets are needed to reliably separate trends from low frequency variability.

  9. Advanced Redox Flow Batteries for Stationary Electrical Energy Storage

    SciTech Connect

    Li, Liyu; Kim, Soowhan; Xia, Guanguang; Wang, Wei; Yang, Zhenguo

    2012-03-19

    This report describes the status of the advanced redox flow battery research being performed at Pacific Northwest National Laboratories for the U.S. Department of Energy’s Energy Storage Systems Program. The Quarter 1 of FY2012 Milestone was completed on time. The milestone entails completion of evaluation and optimization of single cell components for the two advanced redox flow battery electrolyte chemistries recently developed at the lab, the all vanadium (V) mixed acid and V-Fe mixed acid solutions. All the single cell components to be used in future kW-scale stacks have been identified and optimized in this quarter, which include solution electrolyte, membrane or separator; carbon felt electrode and bi-polar plate. Varied electrochemical, chemical and physical evaluations were carried out to assist the component screening and optimization. The mechanisms of the battery capacity fading behavior for the all vanadium redox flow and the Fe/V battery were discovered, which allowed us to optimize the related cell operation parameters and continuously operate the system for more than three months without any capacity decay.

  10. Emissions from Residential Combustion considering End-Uses and Spatial Constraints

    NASA Astrophysics Data System (ADS)

    Bond, T. C.; Lam, N. L.; Winijkul, E.

    2015-12-01

    Cooking, heating, and other activities in the residential sector are major sources of indoor and outdoor air pollution, especially when solid fuels provide energy. Because of these deleterious effects, multinational strategies to alter technology and reduce emissions have been proposed, but to date, they have ignored many constraints on feasibility. We describe a framework to apportion national energy consumption among land types and household end-uses, to calculate emissions, and to evaluate mitigation strategies. We provide year-2010 emissions of particulate matter, black carbon, organic carbon, nitrogen oxides, methane, non-methane hydrocarbons, carbon monoxide, and carbon dioxide. The study area includes regions where solid biomass fuel provides more than 50% of total residential energy: Latin America, Africa, and Asia. Using nightlight data and population density, we classify land types as urban, electrified rural with and without forest access, and non-electrified rural with and without forest access. We apportion national-level residential fuel consumption among land types and end-uses, and assign technologies to each combination. About 13% of energy is consumed in urban areas, and 45% in non-urban land near forests. About half the energy is consumed in land without access to electricity. Cooking accounts for 54% of consumption, heating 9%, and lighting only 2%, with unidentified uses making up the remainder. We examine possible policies, considering realistic factors that constrain mitigation. Scenarios explored are: (1) cleanest current stove, where plausible existing technology is deployed; (2) stove standards, where stoves are designed to meet performance standards; and (3) clean fuels, where users adopt the cleanest plausible fuels; we assume that people living in forest access areas continue to use wood. For cleaner stoves, emission reductions range from 25-82%, depending on the pollutant. The clean-fuels scenario reduces emissions by 18-25%.

  11. Elliptic flow in heavy-ion collisions at NICA energies

    NASA Astrophysics Data System (ADS)

    B. Ivanov, Yu.; Soldatov, A. A.

    2016-08-01

    The transverse-momentum-integrated elliptic flow of charged particles at midrapidity, v2 (charged), and that of identified hadrons from Au+Au collisions are analyzed in the range of incident energies relevant to the Nuclotron-based Ion Collider Facility (NICA). Simulations are performed within a three-fluid model employing three different equations of state (EoSs): a purely hadronic EoS and two versions of the EoS involving the deconfinement transition-a first-order phase transition and a smooth crossover one. The present simulations demonstrate low sensitivity of v2 (charged) to the EoS. All considered scenarios equally well reproduce recent STAR data on v2 (charged) for mid-central Au+Au collisions and properly describe its change of sign at the incident energy decrease below √{s_{NN}} ≈ 3.5 GeV. The predicted integrated elliptic flow of various species exhibits a stronger dependence on the EoS. A noticeable sensitivity to the EoS is found for anti-protons and, to a lesser extent, for K- mesons. Presently there are no experimental data that could verify these predictions. Future experiments at NICA could corroborate these findings.

  12. Residential Lighting End-Use Consumption Study: Estimation Framework and Initial Estimates

    SciTech Connect

    Gifford, Will R.; Goldberg, Miriam L.; Tanimoto, Paulo M.; Celnicker, Dane R.; Poplawski, Michael E.

    2012-12-01

    The U.S. DOE Residential Lighting End-Use Consumption Study is an initiative of the U.S. Department of Energy’s (DOE’s) Solid-State Lighting Program that aims to improve the understanding of lighting energy usage in residential dwellings. The study has developed a regional estimation framework within a national sample design that allows for the estimation of lamp usage and energy consumption 1) nationally and by region of the United States, 2) by certain household characteristics, 3) by location within the home, 4) by certain lamp characteristics, and 5) by certain categorical cross-classifications (e.g., by dwelling type AND lamp type or fixture type AND control type).

  13. End-use matching for solar industrial process heat. Final report

    SciTech Connect

    Brown, K.C.; Hooker, D.W.; Rabl, A.; Stadjuhar, S.A.; West, R.E.

    1980-01-01

    Because of the large energy demand of industry (37% of US demand) and the wide spectrum of temperatures at which heat is required, the industrial sector appears to be very suitable for the matching of solar thermal technology with industrial process heat (IPH) requirements. A methodology for end-use matching has been devised, complete with required data bases and an evaluation program PROSYS/ECONMAT. Six cities in the United States were selected for an analysis of solar applications to IPH. Typical process heat requirements for 70% of the industrial plants in each city were identified and evaluated in conjunction with meteorological and economic data for each site to determine lowest-cost solar systems for each application. The flexibility and scope of PROSYS/ECONMAT is shown in a variety of sensitivity studies that expand the results of the six-city analysis. Case studies of two industrial plants were performed to evaluate the end-use matching procedure; these results are reported.

  14. Dynamics of interaction of directed energy flows with matter

    NASA Astrophysics Data System (ADS)

    Skvortsov, Vladimir A.; Fortov, Vladimir E.

    1992-04-01

    Directed energy flows (DEF), including a High Power ion beams (PIB), are used in different areas of science, engineering and technology. For example, very worth-while is the use of PIB for: the realization of inertial controlled fusion, pumping up gas lasers, the investigations in the area of nuclear physics and energy high density physics, the formation of powerful pulse sources of X-ray and neutron radiation, ion alloying of metals and making surfaces, which improve physical and chemical properties of metals (enlargement of their hardness, corrosion, stability, etc.). The simulation of interaction processes of X-ray radiation with the matter now becomes more actual because of the progress in physics of short length wave laser. High cost and difficulties of the experiments and also the difficulties to get fast changing physical parameters in the area of the DEF--interaction with the target make it necessary to carry out a preliminary computer simulations for the evaluation of the expected physical parameters and the very expediency of such physical experiment. The examples and results of such mathematical simulation on dynamics of intensive pulse actions on metal targets by DEF (high-power ion beams, sharped - charged jets, hypervelocity projectiles, X-ray radiation), are represented in this paper with brief description of used computer models, worked out by High Energy Density Research Center, Russia).

  15. The Redox flow system for solar photovoltaic energy storage

    NASA Technical Reports Server (NTRS)

    Odonnell, P.; Gahn, R. F.

    1976-01-01

    A new method of storage was applied to a solar photovoltaic system. The storage method is a redox flow system which utilizes the oxidation-reduction capability of two soluble electrochemical redox couples for its storage capacity. The particular variant described separates the charging and discharging function of the system such that the electrochemical couples are simultaneously charged and discharged in separate parts of the system. The solar array had 12 solar cells; wired in order to give a range of voltages and currents. The system stored the solar energy so that a load could be run continually day and night. The main advantages of the redox system are that it can accept a charge in the low voltage range and produce a relatively constant output regardless of solar activity.

  16. Energy flow in passive and active 3D cochlear model

    NASA Astrophysics Data System (ADS)

    Wang, Yanli; Puria, Sunil; Steele, Charles

    2015-12-01

    Energy flow in the cochlea is an important characteristic of the cochlear traveling wave, and many investigators, such as von Békésy and Lighthill, have discussed this phenomenon. Particularly after the discovery of the motility of the outer hair cells (OHCs), the nature of the power gain of the cochlea has been a fundamental research question. In the present work, direct three-dimensional (3D) calculations of the power on cross sections of the cochlea and on the basilar membrane are performed based on a box model of the mouse cochlea. The distributions of the fluid pressure and fluid velocity in the scala vestibuli are presented. The power output from the OHCs and the power loss due to fluid viscous damping are calculated along the length of the cochlea. This work provides a basis for theoretical calculations of the power gain of the OHCs from mechanical considerations.

  17. Energy flow in passive and active 3D cochlear model

    SciTech Connect

    Wang, Yanli; Steele, Charles; Puria, Sunil

    2015-12-31

    Energy flow in the cochlea is an important characteristic of the cochlear traveling wave, and many investigators, such as von Békésy and Lighthill, have discussed this phenomenon. Particularly after the discovery of the motility of the outer hair cells (OHCs), the nature of the power gain of the cochlea has been a fundamental research question. In the present work, direct three-dimensional (3D) calculations of the power on cross sections of the cochlea and on the basilar membrane are performed based on a box model of the mouse cochlea. The distributions of the fluid pressure and fluid velocity in the scala vestibuli are presented. The power output from the OHCs and the power loss due to fluid viscous damping are calculated along the length of the cochlea. This work provides a basis for theoretical calculations of the power gain of the OHCs from mechanical considerations.

  18. TEMPO-based catholyte for high-energy density nonaqueous redox flow batteries.

    PubMed

    Wei, Xiaoliang; Xu, Wu; Vijayakumar, Murugesan; Cosimbescu, Lelia; Liu, Tianbiao; Sprenkle, Vincent; Wang, Wei

    2014-12-01

    A TEMPO-based non-aqueous electrolyte with the TEMPO concentration as high as 2.0 m is demonstrated as a high-energy-density catholyte for redox flow battery applications. With a hybrid anode, Li|TEMPO flow cells using this electrolyte deliver an energy efficiency of ca. 70% and an impressively high energy density of 126 W h L(-1) .

  19. Polytropic dark matter flows illuminate dark energy and accelerated expansion

    NASA Astrophysics Data System (ADS)

    Kleidis, K.; Spyrou, N. K.

    2015-04-01

    Currently, a large amount of data implies that the matter constituents of the cosmological dark sector might be collisional. An attractive feature of such a possibility is that, it can reconcile dark matter (DM) and dark energy (DE) in terms of a single component, accommodated in the context of a polytropic-DM fluid. In fact, polytropic processes in a DM fluid have been most successfully used in modeling dark galactic haloes, thus significantly improving the velocity dispersion profiles of galaxies. Motivated by such results, we explore the time evolution and the dynamical characteristics of a spatially-flat cosmological model, in which, in principle, there is no DE at all. Instead, in this model, the DM itself possesses some sort of fluidlike properties, i.e., the fundamental units of the Universe matter-energy content are the volume elements of a DM fluid, performing polytropic flows. In this case, together with all the other physical characteristics, we also take the energy of this fluid's internal motions into account as a source of the universal gravitational field. This form of energy can compensate for the extra energy, needed to compromise spatial flatness, namely, to justify that, today, the total energy density parameter is exactly unity. The polytropic cosmological model, depends on only one free parameter, the corresponding (polytropic) exponent, Γ. We find this model particularly interesting, because for Γ ≤ 0.541, without the need for either any exotic DE or the cosmological constant, the conventional pressure becomes negative enough so that the Universe accelerates its expansion at cosmological redshifts below a transition value. In fact, several physical reasons, e.g., the cosmological requirement for cold DM (CDM) and a positive velocity-of-sound square, impose further constraints on the value of Γ, which is eventually settled down to the range -0.089 < Γ ≤ 0. This cosmological model does not suffer either from the age problem or from the

  20. A Variable Refrigerant Flow Heat Pump Computer Model in EnergyPlus

    SciTech Connect

    Raustad, Richard A.

    2013-01-01

    This paper provides an overview of the variable refrigerant flow heat pump computer model included with the Department of Energy's EnergyPlusTM whole-building energy simulation software. The mathematical model for a variable refrigerant flow heat pump operating in cooling or heating mode, and a detailed model for the variable refrigerant flow direct-expansion (DX) cooling coil are described in detail.

  1. Altered Diastolic Flow Patterns and Kinetic Energy in Subtle Left Ventricular Remodeling and Dysfunction Detected by 4D Flow MRI

    PubMed Central

    Fredriksson, Alexandru; Eriksson, Jonatan; Dyverfeldt, Petter; Ebbers, Tino; Bolger, Ann F.; Engvall, Jan; Carlhäll, Carl-Johan

    2016-01-01

    Aims 4D flow magnetic resonance imaging (MRI) allows quantitative assessment of left ventricular (LV) function according to characteristics of the dynamic flow in the chamber. Marked abnormalities in flow components’ volume and kinetic energy (KE) have previously been demonstrated in moderately dilated and depressed LV’s compared to healthy subjects. We hypothesized that these 4D flow-based measures would detect even subtle LV dysfunction and remodeling. Methods and Results We acquired 4D flow and morphological MRI data from 26 patients with chronic ischemic heart disease with New York Heart Association (NYHA) class I and II and with no to mild LV systolic dysfunction and remodeling, and from 10 healthy controls. A previously validated method was used to separate the LV end-diastolic volume (LVEDV) into functional components: direct flow, which passes directly to ejection, and non-ejecting flow, which remains in the LV for at least 1 cycle. The direct flow and non-ejecting flow proportions of end-diastolic volume and KE were assessed. The proportions of direct flow volume and KE fell with increasing LVEDV-index (LVEDVI) and LVESV-index (LVESVI) (direct flow volume r = -0.64 and r = -0.74, both P<0.001; direct flow KE r = -0.48, P = 0.013, and r = -0.56, P = 0.003). The proportions of non-ejecting flow volume and KE rose with increasing LVEDVI and LVESVI (non-ejecting flow volume: r = 0.67 and r = 0.76, both P<0.001; non-ejecting flow KE: r = 0.53, P = 0.005 and r = 0.52, P = 0.006). The proportion of direct flow volume correlated moderately to LVEF (r = 0.68, P < 0.001) and was higher in a sub-group of patients with LVEDVI >74 ml/m2 compared to patients with LVEDVI <74 ml/m2 and controls (both P<0.05). Conclusion Direct flow volume and KE proportions diminish with increased LV volumes, while non-ejecting flow proportions increase. A decrease in direct flow volume and KE at end-diastole proposes that alterations in these novel 4D flow-specific markers may detect

  2. Analysis of PG&E`s residential end-use metered data to improve electricity demand forecasts -- final report

    SciTech Connect

    Eto, J.H.; Moezzi, M.M.

    1993-12-01

    This report summarizes findings from a unique project to improve the end-use electricity load shape and peak demand forecasts made by the Pacific Gas and Electric Company (PG&E) and the California Energy Commission (CEC). First, the direct incorporation of end-use metered data into electricity demand forecasting models is a new approach that has only been made possible by recent end-use metering projects. Second, and perhaps more importantly, the joint-sponsorship of this analysis has led to the development of consistent sets of forecasting model inputs. That is, the ability to use a common data base and similar data treatment conventions for some of the forecasting inputs frees forecasters to concentrate on those differences (between their competing forecasts) that stem from real differences of opinion, rather than differences that can be readily resolved with better data. The focus of the analysis is residential space cooling, which represents a large and growing demand in the PG&E service territory. Using five years of end-use metered, central air conditioner data collected by PG&E from over 300 residences, we developed consistent sets of new inputs for both PG&E`s and CEC`s end-use load shape forecasting models. We compared the performance of the new inputs both to the inputs previously used by PG&E and CEC, and to a second set of new inputs developed to take advantage of a recently added modeling option to the forecasting model. The testing criteria included ability to forecast total daily energy use, daily peak demand, and demand at 4 P.M. (the most frequent hour of PG&E`s system peak demand). We also tested the new inputs with the weather data used by PG&E and CEC in preparing their forecasts.

  3. Efficient Ionization Investigation for Flow Control and Energy Extraction

    NASA Technical Reports Server (NTRS)

    Schneider, Steven J.; Kamhawi, Hani; Blankson, Isaiah M.

    2009-01-01

    Nonequilibrium ionization of air by nonthermal means is explored for hypersonic vehicle applications. The method selected for evaluation generates a weakly ionized plasma using pulsed nanosecond, high-voltage discharges sustained by a lower dc voltage. These discharges promise to provide a means of energizing and sustaining electrons in the air while maintaining a nearly constant ion/neutral molecule temperature. This paper explores the use of short approx.5 nsec, high-voltage approx.12 to 22 kV, repetitive (40 to 100 kHz) discharges in generating a weakly ionized gas sustained by a 1 kV dc voltage in dry air at pressures from 10 to 80 torr. Demonstrated lifetimes of the sustainer discharge current approx.10 to 25 msec are over three orders of magnitude longer than the 5 nsec pulse that generates the electrons. This life is adequate for many high speed flows, enabling the possibility of exploiting weakly ionized plasma phenomena in flow-fields such as those in hypersonic inlets, combustors, and nozzles. Results to date are obtained in a volume of plasma between electrodes in a bell jar. The buildup and decay of the visible emission from the pulser excited air is photographed on an ICCD camera with nanosecond resolution and the time constants for visible emission decay are observed to be between 10 to 15 nsec decreasing as pressure increases. The application of the sustainer voltage does not change the visible emission decay time constant. Energy consumption as indicated by power output from the power supplies is 194 to 669 W depending on pulse repetition rate.

  4. Residential sector end-use forecasting with EPRI-Reeps 2.1: Summary input assumptions and results

    SciTech Connect

    Koomey, J.G.; Brown, R.E.; Richey, R.

    1995-12-01

    This paper describes current and projected future energy use by end-use and fuel for the U.S. residential sector, and assesses which end-uses are growing most rapidly over time. The inputs to this forecast are based on a multi-year data compilation effort funded by the U.S. Department of Energy. We use the Electric Power Research Institute`s (EPRI`s) REEPS model, as reconfigured to reflect the latest end-use technology data. Residential primary energy use is expected to grow 0.3% per year between 1995 and 2010, while electricity demand is projected to grow at about 0.7% per year over this period. The number of households is expected to grow at about 0.8% per year, which implies that the overall primary energy intensity per household of the residential sector is declining, and the electricity intensity per household is remaining roughly constant over the forecast period. These relatively low growth rates are dependent on the assumed growth rate for miscellaneous electricity, which is the single largest contributor to demand growth in many recent forecasts.

  5. Energy flow, energy density of Timoshenko beam and wave mode incoherence

    NASA Astrophysics Data System (ADS)

    Zhou, Jun; Rao, Zhushi; Ta, Na

    2015-10-01

    Time-averaged energy flow and energy density are of significance in vibration analysis. The wave decomposition method is more fruitful and global in physical sense than the state variables depicted point by point. By wave approach, the Timoshenko beam vibration field is decomposed into two distinct modes: travelling and evanescent waves. Consequently, the power and energy functions defined on these waves' amplitude and phase need to be established. However, such formulas on Timoshenko beam are hardly found in literatures. Furthermore, the incoherence between these two modes is of theoretical and practical significance. This characteristic guarantees that the resultant power or energy of a superposed wave field is equal to the sum of the power or energy that each wave mode would generate individually. Unlike Euler-Bernoulli beam, such incoherence in the Timoshenko beam case has not been theoretically proved so far. Initially, the power and energy formulas based on wave approach and the corresponding incoherence proof are achieved by present work, both in theoretical and numerical ways. Fortunately, the theoretical and numerical results show that the travelling and evanescent wave modes are incoherent with each other both on power and energy functions. Notably, the energy function is unconventional and self-defined in order to obtain the incoherence. Some remarkable power transmission characteristics of the evanescent wave are also illustrated meanwhile.

  6. 7 CFR 782.12 - Filing FSA-750, End-Use Certificate for Wheat.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 7 2012-01-01 2012-01-01 false Filing FSA-750, End-Use Certificate for Wheat. 782.12... Certificate Program § 782.12 Filing FSA-750, End-Use Certificate for Wheat. (a) Each entity that imports wheat originating in Canada shall, for each entry into the U.S., obtain form FSA-750, End-Use Certificate for...

  7. 7 CFR 782.12 - Filing FSA-750, End-Use Certificate for Wheat.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Filing FSA-750, End-Use Certificate for Wheat. 782.12... Certificate Program § 782.12 Filing FSA-750, End-Use Certificate for Wheat. (a) Each entity that imports wheat originating in Canada shall, for each entry into the U.S., obtain form FSA-750, End-Use Certificate for...

  8. 7 CFR 782.12 - Filing FSA-750, End-Use Certificate for Wheat.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 7 2013-01-01 2013-01-01 false Filing FSA-750, End-Use Certificate for Wheat. 782.12... Certificate Program § 782.12 Filing FSA-750, End-Use Certificate for Wheat. (a) Each entity that imports wheat originating in Canada shall, for each entry into the U.S., obtain form FSA-750, End-Use Certificate for...

  9. 7 CFR 782.12 - Filing FSA-750, End-Use Certificate for Wheat.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 7 2011-01-01 2011-01-01 false Filing FSA-750, End-Use Certificate for Wheat. 782.12... Certificate Program § 782.12 Filing FSA-750, End-Use Certificate for Wheat. (a) Each entity that imports wheat originating in Canada shall, for each entry into the U.S., obtain form FSA-750, End-Use Certificate for...

  10. 7 CFR 782.12 - Filing FSA-750, End-Use Certificate for Wheat.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 7 2014-01-01 2014-01-01 false Filing FSA-750, End-Use Certificate for Wheat. 782.12... Certificate Program § 782.12 Filing FSA-750, End-Use Certificate for Wheat. (a) Each entity that imports wheat originating in Canada shall, for each entry into the U.S., obtain form FSA-750, End-Use Certificate for...

  11. Energy and momentum flow in electromagnetic fields and plasma. [solar wind-magnetospheric interaction

    NASA Technical Reports Server (NTRS)

    Parish, J. L.; Raitt, W. J.

    1983-01-01

    The energy momentum tensor for a perfect fluid in a magnetic field is used to predict the momentum density, energy density, momentum flow, and energy flow of the fluid and the electromagnetic field. It is shown that taking the momentum flow from the energy momentum tensor, rather than starting with differential magnetohydrodynamic equations, can produce more accurate results on the basis of magnetic field data. It is suggested that the use of the energy momentum tensor has the potential for application to analysis of data from the more dynamic regions of the solar system, such as the plasma boundaries of Venus, the Jovian ionosphere, and the terrestrial magnetopause.

  12. Measurements of energy distribution and wall temperature in flowing hydrogen microwave plasma systems

    NASA Technical Reports Server (NTRS)

    Chapman, R.; Finzel, M.; Hawley, M. C.

    1985-01-01

    An electrothermal propulsion concept utilizing a microwave plasma system as the mechanism to convert electromagnetic energy into translational energy of the flowing gas is being investigated. A calorimetric experimental system has been designed and built enclosing the microwave plasma system to accurately determine the net energy transferred to the flowing gas. For a flow rate of 8900 micromoles/sec, a pressure of 7.4 torr, and an absorbed power level of 80 W, an energy transfer efficiency of 50 percent has been measured. A heat transfer model that characterizes the energy transfer processes in the plasma is developed. A wall temperature for the plasma system is calculated.

  13. Developing a demand model integrating end uses of water (DMEUW): structure and process of integration.

    PubMed

    Sarker, R C; Gato-Trinidad, S

    2015-01-01

    The process of developing an integrated water demand model integrating end uses of water has been presented. The model estimates and forecasts average daily water demand based on the end-use pattern and trend of residential water consumption, daily rainfall and temperature, water restrictions and water conservation programmes. The end-use model uses the latest end-use data set collected from Yarra Valley Water, Australia. A computer interface has also been developed using hypertext markup language and hypertext pre-processor. The developed model can be used by water authorities and water resource planners in forecasting water demand and by household owners in determining household water consumption. PMID:25746644

  14. Energy flow and the “grassification” of desert shrublands

    USGS Publications Warehouse

    Betancourt, Julio L.

    2015-01-01

    In our directionally and continuously changing world, history still matters, and it does so in increasingly novel and important ways. Human adaptation to global change will rely heavily on robust baselines of historic environmental variability and detailed understanding of how both past and modern ecosystems have responded to both individual and multiple stressors. The question of global change has motivated an upsurge in paleoecological studies that span the late Quaternary and the modern era, and has inspired a growing consideration of time as a fundamental axis in ecology (1). A major challenge in developing pertinent ecological baselines remains how to fuse, into continuous time series, observations and experiments from living systems with paleoecological reconstructions from the same sites (2, 3). Tracing and disentangling complex responses to environmental stress from paleological to present-day communities is especially daunting; for example, how climate change; accelerated land use; and biological invasions are influencing the flows of water, nutrients, and energy. The paper by Terry and Rowe in PNAS (4) is a shining example of how modern ecology and paleoecology can be spliced together to decipher how ecological processes unfold over time scales inaccessible to direct observation or experimentation, and how they can be disrupted by human impacts.

  15. Design Flexibility of Redox Flow Systems. [for energy storage applications

    NASA Technical Reports Server (NTRS)

    Hagedorn, N. H.; Thaller, L. H.

    1982-01-01

    The characteristics inherent in Redox flow systems permit considerable latitude in designing systems for specific storage applications. The first of these characteristics is the absence of plating/deplating reactions with their attendant morphology changes at the electrodes. This permits a given Redox system to operate over a wide range of depths of discharge and charge/discharge rates. The second characteristic is the separation of power generating components (stacks) from the energy storage components (tanks). This results in cost effective system design, ease of system growth via modularization, and freedom from sizing restraints so that the whole spectrum of applications, from utilities down to single residence can be considered. The final characteristic is the commonality of the reactant fluids which assures that all cells at all times are receiving reactants at the same state of charge. Since no cell can be out of balance with respect to any other cell, it is possible for some cells to be charged while others are discharging, in effect creating a DC to DC transformer. It is also possible for various groups of cells to be connected to separate loads, thus supplying a range of output voltages. Also, trim cells can be used to maintain constant bus voltage as the load is changed or as the depth of discharge increases. The commonality of reactant fluids also permits any corrective measures such as rebalancing to occur at the system level instead of at the single cell level.

  16. High-energy redox-flow batteries with hybrid metal foam electrodes.

    PubMed

    Park, Min-Sik; Lee, Nam-Jin; Lee, Seung-Wook; Kim, Ki Jae; Oh, Duk-Jin; Kim, Young-Jun

    2014-07-01

    A nonaqueous redox-flow battery employing [Co(bpy)3](+/2+) and [Fe(bpy)3](2+/3+) redox couples is proposed for use in large-scale energy-storage applications. We successfully demonstrate a redox-flow battery with a practical operating voltage of over 2.1 V and an energy efficiency of 85% through a rational cell design. By utilizing carbon-coated Ni-FeCrAl and Cu metal foam electrodes, the electrochemical reactivity and stability of the nonaqueous redox-flow battery can be considerably enhanced. Our approach intoduces a more efficient conversion of chemical energy into electrical energy and enhances long-term cell durability. The cell exhibits an outstanding cyclic performance of more than 300 cycles without any significant loss of energy efficiency. Considering the increasing demands for efficient energy storage, our achievement provides insight into a possible development pathway for nonaqueous redox-flow batteries with high energy densities.

  17. Meters to answer needs for low-cost EFM, energy measurement. [Electronic Flow Measurement

    SciTech Connect

    Not Available

    1994-03-07

    Research supported by the Gas Research Institute, Chicago, will produce two commercial measurements devices by mid-year. One is a low-cost, compact electronic flow measurement (EFM) system for orifice flow monitoring and custody transfer; the other, an instrument for measuring natural-gas energy and volume flow in pipelines. The paper describes a low-cost EFM, field testing, a total-energy meter, theory of operation, and improvements.

  18. Numerical model for the flow within the tower of a tornado-type wind energy system

    SciTech Connect

    Ayad, S.S.

    1981-11-01

    A two-equation turbulence model is used to predict numerically the flow within the tower of a tornado-type wind energy system. Calculations are carried out for a tower in a uniform flow. Both cases of closed-bottom tower and simulated turbine flow with a variety of turbine-to-tower diameter ratios and turbine flow rates are considered. Calculated values of pressure for closed-bottom tower are compared with experimental values. 11 refs.

  19. High-energy density nonaqueous all redox flow lithium battery enabled with a polymeric membrane.

    PubMed

    Jia, Chuankun; Pan, Feng; Zhu, Yun Guang; Huang, Qizhao; Lu, Li; Wang, Qing

    2015-11-01

    Redox flow batteries (RFBs) are considered one of the most promising large-scale energy storage technologies. However, conventional RFBs suffer from low energy density due to the low solubility of the active materials in electrolyte. On the basis of the redox targeting reactions of battery materials, the redox flow lithium battery (RFLB) demonstrated in this report presents a disruptive approach to drastically enhancing the energy density of flow batteries. With LiFePO4 and TiO2 as the cathodic and anodic Li storage materials, respectively, the tank energy density of RFLB could reach ~500 watt-hours per liter (50% porosity), which is 10 times higher than that of a vanadium redox flow battery. The cell exhibits good electrochemical performance under a prolonged cycling test. Our prototype RFLB full cell paves the way toward the development of a new generation of flow batteries for large-scale energy storage. PMID:26702440

  20. High–energy density nonaqueous all redox flow lithium battery enabled with a polymeric membrane

    PubMed Central

    Jia, Chuankun; Pan, Feng; Zhu, Yun Guang; Huang, Qizhao; Lu, Li; Wang, Qing

    2015-01-01

    Redox flow batteries (RFBs) are considered one of the most promising large-scale energy storage technologies. However, conventional RFBs suffer from low energy density due to the low solubility of the active materials in electrolyte. On the basis of the redox targeting reactions of battery materials, the redox flow lithium battery (RFLB) demonstrated in this report presents a disruptive approach to drastically enhancing the energy density of flow batteries. With LiFePO4 and TiO2 as the cathodic and anodic Li storage materials, respectively, the tank energy density of RFLB could reach ~500 watt-hours per liter (50% porosity), which is 10 times higher than that of a vanadium redox flow battery. The cell exhibits good electrochemical performance under a prolonged cycling test. Our prototype RFLB full cell paves the way toward the development of a new generation of flow batteries for large-scale energy storage. PMID:26702440

  1. High-energy density nonaqueous all redox flow lithium battery enabled with a polymeric membrane.

    PubMed

    Jia, Chuankun; Pan, Feng; Zhu, Yun Guang; Huang, Qizhao; Lu, Li; Wang, Qing

    2015-11-01

    Redox flow batteries (RFBs) are considered one of the most promising large-scale energy storage technologies. However, conventional RFBs suffer from low energy density due to the low solubility of the active materials in electrolyte. On the basis of the redox targeting reactions of battery materials, the redox flow lithium battery (RFLB) demonstrated in this report presents a disruptive approach to drastically enhancing the energy density of flow batteries. With LiFePO4 and TiO2 as the cathodic and anodic Li storage materials, respectively, the tank energy density of RFLB could reach ~500 watt-hours per liter (50% porosity), which is 10 times higher than that of a vanadium redox flow battery. The cell exhibits good electrochemical performance under a prolonged cycling test. Our prototype RFLB full cell paves the way toward the development of a new generation of flow batteries for large-scale energy storage.

  2. 77 FR 51459 - Suspension of End-Use Certificate Program Requirements

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-24

    ...) regulation requiring end-use certificates and tracking of wheat produced in Canada that enters the United... program. As a result of these changes, importers and end- users of Canadian produced wheat are no longer required to provide FSA end-use certificates or consumption and resale reports on wheat produced in...

  3. 15 CFR 744.4 - Restrictions on certain chemical and biological weapons end-uses.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... biological weapons end-uses. 744.4 Section 744.4 Commerce and Foreign Trade Regulations Relating to Commerce... and biological weapons end-uses. (a) General prohibition. In addition to the license requirements for... biological weapons in or by any country or destination, worldwide. (b) Additional prohibition on...

  4. 15 CFR 745.2 - End-Use Certificate reporting requirements under the Chemical Weapons Convention.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... requirements under the Chemical Weapons Convention. 745.2 Section 745.2 Commerce and Foreign Trade Regulations... EXPORT ADMINISTRATION REGULATIONS CHEMICAL WEAPONS CONVENTION REQUIREMENTS § 745.2 End-Use Certificate reporting requirements under the Chemical Weapons Convention. Note: The End-Use Certificate requirement...

  5. 15 CFR 745.2 - End-Use Certificate reporting requirements under the Chemical Weapons Convention.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... requirements under the Chemical Weapons Convention. 745.2 Section 745.2 Commerce and Foreign Trade Regulations... EXPORT ADMINISTRATION REGULATIONS CHEMICAL WEAPONS CONVENTION REQUIREMENTS § 745.2 End-Use Certificate reporting requirements under the Chemical Weapons Convention. Note: The End-Use Certificate requirement...

  6. 15 CFR 745.2 - End-Use Certificate reporting requirements under the Chemical Weapons Convention.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... requirements under the Chemical Weapons Convention. 745.2 Section 745.2 Commerce and Foreign Trade Regulations... EXPORT ADMINISTRATION REGULATIONS CHEMICAL WEAPONS CONVENTION REQUIREMENTS § 745.2 End-Use Certificate reporting requirements under the Chemical Weapons Convention. Note: The End-Use Certificate requirement...

  7. 15 CFR 744.4 - Restrictions on certain chemical and biological weapons end-uses.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... biological weapons end-uses. 744.4 Section 744.4 Commerce and Foreign Trade Regulations Relating to Commerce... and biological weapons end-uses. (a) General prohibition. In addition to the license requirements for... biological weapons in or by any country or destination, worldwide. (b) Additional prohibition on...

  8. 15 CFR 744.4 - Restrictions on certain chemical and biological weapons end-uses.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... biological weapons end-uses. 744.4 Section 744.4 Commerce and Foreign Trade Regulations Relating to Commerce... and biological weapons end-uses. (a) General prohibition. In addition to the license requirements for... biological weapons in or by any country or destination, worldwide. (b) Additional prohibition on...

  9. 15 CFR 745.2 - End-Use Certificate reporting requirements under the Chemical Weapons Convention.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... requirements under the Chemical Weapons Convention. 745.2 Section 745.2 Commerce and Foreign Trade Regulations... EXPORT ADMINISTRATION REGULATIONS CHEMICAL WEAPONS CONVENTION REQUIREMENTS § 745.2 End-Use Certificate reporting requirements under the Chemical Weapons Convention. Note: The End-Use Certificate requirement...

  10. 15 CFR 744.4 - Restrictions on certain chemical and biological weapons end-uses.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... biological weapons end-uses. 744.4 Section 744.4 Commerce and Foreign Trade Regulations Relating to Commerce... and biological weapons end-uses. (a) General prohibition. In addition to the license requirements for... biological weapons in or by any country or destination, worldwide. (b) Additional prohibition on...

  11. 15 CFR 744.5 - Restrictions on certain maritime nuclear propulsion end-uses.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... nuclear propulsion end-uses. 744.5 Section 744.5 Commerce and Foreign Trade Regulations Relating to... nuclear propulsion end-uses. (a) General prohibition. In addition to the license requirements for items... item is for use in connection with a foreign maritime nuclear propulsion project. This...

  12. 15 CFR 744.5 - Restrictions on certain maritime nuclear propulsion end-uses.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... nuclear propulsion end-uses. 744.5 Section 744.5 Commerce and Foreign Trade Regulations Relating to... nuclear propulsion end-uses. (a) General prohibition. In addition to the license requirements for items... item is for use in connection with a foreign maritime nuclear propulsion project. This...

  13. End-use quality of U.S. soft white winter and spring wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    End-use quality of wheat grain is central to the breeding, selection, production, marketing, use, and value of varieties. The objective assessment of the end-use quality of individual wheat varieties and advance breeding lines in the U.S. often falls under the purview of the U.S.D.A. Agricultural Re...

  14. 15 CFR 745.2 - End-Use Certificate reporting requirements under the Chemical Weapons Convention.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... requirements under the Chemical Weapons Convention. 745.2 Section 745.2 Commerce and Foreign Trade Regulations... EXPORT ADMINISTRATION REGULATIONS CHEMICAL WEAPONS CONVENTION REQUIREMENTS § 745.2 End-Use Certificate reporting requirements under the Chemical Weapons Convention. Note: The End-Use Certificate requirement...

  15. 15 CFR 744.4 - Restrictions on certain chemical and biological weapons end-uses.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... biological weapons end-uses. 744.4 Section 744.4 Commerce and Foreign Trade Regulations Relating to Commerce... and biological weapons end-uses. (a) General prohibition. In addition to the license requirements for... biological weapons in or by any country or destination, worldwide. (b) Additional prohibition on...

  16. 15 CFR 744.5 - Restrictions on certain maritime nuclear propulsion end-uses.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... nuclear propulsion end-uses. 744.5 Section 744.5 Commerce and Foreign Trade Regulations Relating to... nuclear propulsion end-uses. (a) General prohibition. In addition to the license requirements for items... item is for use in connection with a foreign maritime nuclear propulsion project. This...

  17. 15 CFR 744.5 - Restrictions on certain maritime nuclear propulsion end-uses.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... nuclear propulsion end-uses. 744.5 Section 744.5 Commerce and Foreign Trade Regulations Relating to... nuclear propulsion end-uses. (a) General prohibition. In addition to the license requirements for items... item is for use in connection with a foreign maritime nuclear propulsion project. This...

  18. 15 CFR 744.5 - Restrictions on certain maritime nuclear propulsion end-uses.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... nuclear propulsion end-uses. 744.5 Section 744.5 Commerce and Foreign Trade Regulations Relating to... nuclear propulsion end-uses. (a) General prohibition. In addition to the license requirements for items... item is for use in connection with a foreign maritime nuclear propulsion project. This...

  19. Global warming and end-use efficiency implications of replacing CFCs

    SciTech Connect

    Fairchild, P.D.; Fischer, S.K.

    1991-12-31

    The direct contribution of CFCs to calculated global warming has been recognized for some time. As a result of the international agreement to phase out CFCs due to stratospheric ozone and the ensuing search for suitable alternatives, there has recently been increased attention on the DIRECT global warming potential (GWP) of the fluorocarbon alternatives as greenhouse gases. However, to date there has been little focus on the INDIRECT global warming effect arising from end-use efficiency changes and associated CO{sub 2} emissions. A study being conducted at Oak Ridge National Laboratory (ORNL) addresses this combined or total global warming impact of viable options to replace CFCs in their major energy-related applications. This paper reviews selected results for air-conditioning, refrigeration, and heat pump applications. The analysis indicates that the CFC user industries have made substantial progress in approaching near-equal energy efficiency with the HCFC/HFC alternative refrigerants. The findings also bring into question the relative importance of the DIRECT (chemical-related) effect in many applications. Replacing CFCs is an important step in reducing the total global warming impact, and at present the HCFC and HFCS appear to offer the best efficiency and lowest total impact of options available in the relatively short time period required for the transition away from CFCs.

  20. Coupling nutrient uptake and energy flow in headwater streams

    SciTech Connect

    Mulholland, Patrick J; Fellows, Christine; Valett, H. Maurice; Dahm, Cliff; Thomas, Steve

    2006-08-01

    Nutrient cycling and energy flow in ecosystems are tightly linked through the metabolic processes of organisms. Greater uptake of inorganic nutrients is expected to be associated with higher rates of metabolism [gross primary production (GPP) and respiration (R)], due to assimilatory demand of both autotrophs and heterotrophs. However, relationships between uptake and metabolism should vary with the relative contribution of autochthonous and allochthonous sources of organic matter. To investigate the relationship between metabolism and nutrient uptake, we used whole-stream and benthic chamber methods to measure rates of nitrate-nitrogen (NO{sub 3}-N) uptake and metabolism in four headwater streams chosen to span a range of light availability and therefore differing rates of GPP and contributions of autochthonous carbon. We coupled whole-stream metabolism with measures of NO{sub 3}-N uptake conducted repeatedly over the same stream reach during both day and night, as well as incubating benthic sediments under both light and dark conditions. NO{sub 3}-N uptake was generally greater in daylight compared to dark conditions, and although day-night differences in whole-stream uptake were not significant, light-dark differences in benthic chambers were significant at three of the four sites. Estimates of N demand indicated that assimilation by photoautotrophs could account for the majority of NO{sub 3}-N uptake at the two sites with relatively open canopies. Contrary to expectations, photoautotrophs contributed substantially to NO{sub 3}-N uptake even at the two closed-canopy sites, which had low values of GPP/R and relied heavily on allochthonous carbon to fuel R.

  1. Emissions from residential combustion considering end-uses and spatial constraints: Part I, methods and spatial distribution

    NASA Astrophysics Data System (ADS)

    Winijkul, Ekbordin; Fierce, Laura; Bond, Tami C.

    2016-01-01

    This study describes a framework to attribute national-level atmospheric emissions in the year 2010 from the residential sector, one of the largest energy-related sources of aerosol emissions. We place special emphasis on end-uses, dividing usage into cooking, heating, lighting, and others. This study covers regions where solid biomass fuel provides more than 50% of total residential energy: Latin America, Africa, and Asia (5.2 billion people in 2010). Using nightlight data and population density, we classify five land types: urban, electrified rural with forest access, electrified rural without forest access, non-electrified rural with forest access, and non-electrified rural without forest access. We then apportion national-level residential fuel consumption among all land-types and end-uses, and assign end-use technologies to each combination. The resulting calculation gives spatially-distributed emissions of particulate matter, black carbon, organic carbon, nitrogen oxides, methane, non-methane hydrocarbons, carbon monoxide, and carbon dioxide. Within this study region, about 13% of the energy is consumed in urban areas, and 45% in non-urban land near forests. About half the energy is consumed in land without access to electricity. Cooking accounts for 54% of the consumption, heating for 9%, and lighting only 2%, with unidentified uses making up the remainder. Because biofuel use is assumed to occur preferentially where wood is accessible and electricity is not, our method shifts emissions to land types without electrification, compared with previous methods. The framework developed here is an important first step in acknowledging the role of household needs and local constraints in choosing energy provision. Although data and relationships described here need further development, this structure offers a more physically-based understanding of residential energy choices and, ultimately, opportunities for emission reduction.

  2. TEMPO-based catholyte for high-energy density nonaqueous redox flow batteries.

    PubMed

    Wei, Xiaoliang; Xu, Wu; Vijayakumar, Murugesan; Cosimbescu, Lelia; Liu, Tianbiao; Sprenkle, Vincent; Wang, Wei

    2014-12-01

    A TEMPO-based non-aqueous electrolyte with the TEMPO concentration as high as 2.0 m is demonstrated as a high-energy-density catholyte for redox flow battery applications. With a hybrid anode, Li|TEMPO flow cells using this electrolyte deliver an energy efficiency of ca. 70% and an impressively high energy density of 126 W h L(-1) . PMID:25327755

  3. Dynamics of suspended microchannel resonators conveying opposite internal fluid flow: Stability, frequency shift and energy dissipation

    NASA Astrophysics Data System (ADS)

    Zhang, Wen-Ming; Yan, Han; Jiang, Hui-Ming; Hu, Kai-Ming; Peng, Zhi-Ke; Meng, Guang

    2016-04-01

    In this paper, the dynamics of suspended microchannel resonators which convey internal flows with opposite directions are investigated. The fluid-structure interactions between the laminar fluid flow and oscillating cantilever are analyzed by comprehensively considering the effects of velocity profile, flow viscosity and added flowing particle. A new model is developed to characterize the dynamic behavior of suspended microchannel resonators with the fluid-structure interactions. The stability, frequency shift and energy dissipation of suspended microchannel resonators are analyzed and discussed. The results demonstrate that the frequency shifts induced by the added flowing particle which are obtained from the new model have a good agreement with the experimental data. The steady mean flow can cause the frequency shift and influence the stability of the dynamic system. As the flow velocity reaches the critical value, the coupled-mode flutter occurs via a Hamiltonian Hopf bifurcation. The perturbation flow resulted from the vibration of the microcantilever leads to energy dissipation, while the steady flow does not directly cause the damping which increases with the increasing of the flow velocity predicted by the classical model. It can also be found that the steady flow firstly changes the mode shape of the cantilever and consequently affects the energy dissipation.

  4. Pulsed-flow air classification for waste to energy production. Final report

    SciTech Connect

    Peirce, J.J.; Vesilind, P.A.

    1983-09-30

    The development and testing of pulsed-flow air classification for waste-to-energy production are discussed. Standard designs generally permit large amounts of combustible material to escape as reject while producing a fuel that is high in metal and glass contaminants. Pulsed-flow classification is presented as a concept which can avoid both pitfalls. Each aspect of theory and laboratory testing is summarized: particle characteristics, theory of pulsed-flow classification, laboratory testing, and pulsed-flow air classification for waste-to-energy production. Conclusions from the research are summarized.

  5. Energy and pseudoenergy flux in the internal wave field generated by tidal flow over topography

    NASA Astrophysics Data System (ADS)

    Lamb, Kevin G.

    2007-05-01

    The mechanical energy and pseudoenergy budgets in the internal wave field generated by tidal flow over topography is considered using a nonlinear, two-dimensional numerical model. The Boussinesq and rigid lid approximations are made, viscosity and diffusion are ignored and the flow is treated as incompressible. Both ridge and bank edge topographies are considered. The nonlinear energy equation and an equation for pseudoenergy (kinetic energy plus available potential energy) are satisfied to within less than 1%. For a uniform stratification (constant buoyancy frequency N) the available potential energy density is identical to the linear potential energy density {1}/{2}(g2/N2)ρ˜d2 where ρ is the density perturbation. For weak tidal flow over a ridge in the deep ocean, using a uniform stratification, the generated waves are small, approximately 2% of the water depth, and the traditional expression for the energy flux, accurately gives the pseudoenergy flux. For a case with strong tidal flow across a bank edge, using a non-uniform stratification, large internal solitary waves are generated. In this case, the linear form of the potential energy is very different from the available potential energy and the traditional energy flux term accounts for only half of the pseudoenergy flux. Fluxes of kinetic and available potential energy are comparable to the traditional energy flux term and hence must be included when estimating energy fluxes in the internal wave field.

  6. Analyzing stability of compressible, swirling pipe flows using disturbance energy mechanisms

    NASA Astrophysics Data System (ADS)

    Samanta, Arnab

    2015-11-01

    We investigate the spatial stability of compressible, viscous pipe flows with radius-dependent mean density profiles, subjected to solid body rotations. Holding the flow Reynolds number fixed, as the Rossby number is lowered (increased swirl), flow usually transitions from being stable to convectively unstable, finally leading to absolute instability. In this work, the role of compressibility on flow stability is characterized via specifying stratified mean densities where for certain choices the flow appears to be unconditionally stable while for others the situation is more complex with an initially convectively unstable state becoming stable as rotational speeds are progressively raised. A disturbance energy-based method is used to obtain physical understanding of the instability mechanisms in such flows with special emphasis on the role of compressibility. We observe that mechanisms due to pressure energy redistribution and entropy perturbations dominate as primary instability mechanisms instead of the energy due to shear in axial velocity, the primary source of instability in incompressible flows. With reference to pipe flows, we quantify the complex interplay between the various energy mechanisms to provide physical insight into the stability of compressible swirling flows.

  7. Energy flow in high speed perforation and cutting

    SciTech Connect

    van Thiel, M.

    1980-10-07

    It is demonstrated that effects of long rod penetrators on targets can be modeled by introducing a high pressure (energy) column on the penetration path in place of the projectile. This energy can be obtained from the kinetic energy of the penetrator; the equations of state of the materials used and a Bernoulli penetration condition. The model is supported by detailed hydro calculations.

  8. Bidirectional control system for energy flow in solar powered flywheel

    NASA Technical Reports Server (NTRS)

    Nola, Frank J. (Inventor)

    1987-01-01

    An energy storage system for a spacecraft is provided which employs a solar powered flywheel arrangement including a motor/generator which, in different operating modes, drives the flywheel and is driven thereby. A control circuit, including a threshold comparator, senses the output of a solar energy converter, and when a threshold voltage is exceeded thereby indicating the availability of solar power for the spacecraft loads, activates a speed control loop including the motor/generator so as to accelerate the flywheel to a constant speed and thereby store mechanical energy, while also supplying energy from the solar converter to the loads. Under circumstances where solar energy is not available and thus the threshold voltage is not exceeded, the control circuit deactivates the speed control loop and activates a voltage control loop that provides for operation of the motor as a generator so that mechanical energy from the flywheel is converted into electrical energy for supply to the spacecraft loads.

  9. System Size, Energy, Pseudorapidity, and Centrality Dependence of Elliptic Flow

    SciTech Connect

    Alver, B.; Ballintijn, M.; Busza, W.; Decowski, M. P.; Gulbrandsen, K.; Henderson, C.; Kane, J. L.; Kulinich, P.; Li, W.; Loizides, C.; Reed, C.; Roland, C.; Roland, G.; Stephans, G. S. F.; Vale, C.; Nieuwenhuizen, G. J. van; Vaurynovich, S. S.; Verdier, R.; Veres, G. I.; Wenger, E.

    2007-06-15

    This Letter presents measurements of the elliptic flow of charged particles as a function of pseudorapidity and centrality from Cu-Cu collisions at 62.4 and 200 GeV using the PHOBOS detector at the Relativistic Heavy Ion Collider. The elliptic flow in Cu-Cu collisions is found to be significant even for the most central events. For comparison with the Au-Au results, it is found that the detailed way in which the collision geometry (eccentricity) is estimated is of critical importance when scaling out system-size effects. A new form of eccentricity, called the participant eccentricity, is introduced which yields a scaled elliptic flow in the Cu-Cu system that has the same relative magnitude and qualitative features as that in the Au-Au system.

  10. Process simulator for time-dependent material and energy flow in a continuous casting system

    SciTech Connect

    Westerberg, K.W.; McClelland, M.A.

    1995-02-06

    A process simulator is developed for the material and energy flow in a continuous casting system which utilizes an electron-beam energy source. A time-dependent, one-dimensional model is used which accounts for energy transport within the ingot and transport to the surroundings by conduction, thermal radiation, and the formation of secondary electrons. Also included are the mass and energy additions associated with the poured metal. A modified finite element method is used to solve the energy equation while tracking boundaries at the pool surface and solidification zone. Model parameters are determined using results from a steady-state experiment and a more detailed two-dimensional model for fluid flow and energy transport. For a transient experiment with pouring, a comparison is made between predicted and measured heat flows.

  11. Anisotropic low-wavenumber constraints on energy in rotating and stratified flows

    NASA Astrophysics Data System (ADS)

    Kurien, Susan; Wingate, Beth; Taylor, Mark

    2007-11-01

    Rapidly rotating, stably stratified three-dimensional inviscid flows conserve both energy and potential enstrophy. We show that in such flows, the forward cascade of potential enstrophy imposes anisotropic constraints on the wavenumber distribution of kinetic and potential energy. The horizontal kinetic energy is suppressed in the large, nearly horizontal wave modes, and should decay with the horizontal wavenumber as kh-3. The potential energy is suppressed in the large, nearly vertical wave modes, and should decay with the vertical wavenumber as kz-3 . These results augment the only other exact prediction for the scaling of energy spectra due to constraints by potential enstrophy obtained by Charney (J. Atmos. Sci. 28, 1087 (1971)), who showed that in the quasi-geostrophic approximation for rotating stratified flows, the energy spectra must scale isotropically with total wavenumber as k-3. We test our predicted scaling estimates using resolved numerical simulations of the Boussinesq equations in the relevant parameter regimes, and find reasonable agreement.

  12. Food Utilization (Energy-Flow) Investigations with Pieris Brassicae (Large White) Caterpillars.

    ERIC Educational Resources Information Center

    Jones, Derek H. T.

    1985-01-01

    Background information, procedures used, and typical results obtained are provided for experiments in which caterpillars are used to investigate energy-flow relationships. Areas in which the experiments could be used include ecology, applied biology, and animal feeding. (DH)

  13. Electromagnetic energy and energy flows in photonic crystals made of arrays of parallel dielectric cylinders.

    PubMed

    Kuo, Chao-Hsien; Ye, Zhen

    2004-10-01

    We consider electromagnetic propagation in two-dimensional photonic crystals, formed by parallel dielectric cylinders embedded a uniform medium. The frequency band structure is computed using the standard plane-wave expansion method, and the corresponding eigenmodes are obtained subsequently. The optical flows of the eigenmodes are calculated by a direct computation approach, and several averaging schemes of the energy current are discussed. The results are compared to those obtained by the usual approach that employs a group velocity calculation. We consider both the case in which the frequency lies within passing band and the situation in which the frequency is in the range of a partial band gap. The agreements and discrepancies between various averaging schemes and the group velocity approach are discussed in detail. The results indicate that the group velocity can be obtained by an appropriate averaging method. Existing experimental methods are also discussed.

  14. Flow depth and energy coefficient relatiohnships for stepped spillways

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A multi-year, large-scale physical model study of stepped chutes was conducted over a broad range of design parameters (i.e. step heights, slopes, and unit discharges). Air entrainment developed naturally as the flow descended the chute. Air entrainment began to develop downstream of the surface i...

  15. An analysis of the acoustic energy in a flow duct with a vortex sheet

    NASA Astrophysics Data System (ADS)

    Boij, Susann

    2009-03-01

    Modelling the acoustic scattering and absorption at an area expansion in a flow duct requires the incorporation of the flow-acoustic interaction. One way to quantify the interaction is to study the energy in the incident and the scattered field respectively. If the interaction is strong, energy may be transferred between the acoustic and the main flow field. In particular, shear layers, that may be the result of the flow separation, are unstable to low frequency perturbations such as acoustic waves. The vortex sheet model is an analytical linear acoustic model, developed to study scattering of acoustic waves in duct with sharp edges including the interaction with primarily the separated flows that arise at sharp edges and corners. In the model the flow field at an area expansion in a duct is described as a jet issuing into the larger part of the duct. In this paper, the flow-acoustic interaction is described in terms of energy flow. The linear convective wave equation is solved for a two-dimensional, rectangular flow duct geometry. The resulting modes are classified as "hydrodynamic" and "acoustic" when separating the acoustic energy from the part of the energy arising from the steady flow field. In the downstream duct, the set of modes for this complex flow field are not orthogonal. For small Strouhal numbers, the plane wave and the two hydrodynamic waves are all plane, although propagating with different wave speeds. As the Strouhal numbers increases, the hydrodynamic modes changes to get a shape where the amplitude is concentrated near the vortex sheet. In an intermediate Strouhal number region, the mode shape of the first higher order mode is very similar to the damped hydrodynamic mode. A physical interpretation of this is that we have a strong coupling between the flow field and the acoustic field when the modes are non-orthogonal. Energy concepts for this duct configuration and mean flow profile are introduced. The energy is formulated such that the vortex

  16. Experimental investigations of the swirling flow in the conical diffuser using flow-feedback control technique with additional energy source

    NASA Astrophysics Data System (ADS)

    Tǎnasǎ, C.; Bosioc, A. I.; Susan-Resiga, R. F.; Muntean, S.

    2012-11-01

    The previous experimental and numerical investigations of decelerated swirling flows in conical diffusers have demonstrated that water injection along to the axis mitigates the pressure fluctuations associated to the precessing vortex rope [1]. However, for swirling flows similar to Francis turbines operated at partial discharge, the water jet becomes effective when the jet discharge is larger than 10% from the turbine discharge, leading to large volumetric losses when the jet is supplied from upstream the runner. As a result, it was introduced a new approach for supplying the jet by using a fraction of the discharge collected downstream the conical diffuser [2]. This is called flow-feedback control technique (FFCT) and it was investigated experimentally in order to assess its capability [3]. The FFCT approach not requires additional energy to supply the jet. Consequently, the turbine efficiency is not diminished due to the volumetric losses injected even if around 10% of the main flow is used. However, the equivalent amplitude of the pressure pulsations associated to the vortex rope decreases with 30% if 10% jet discharge is applied [3]. Using 12% water jet discharge from upstream then the equivalent amplitude of the pressure pulsations is mitigated with 70% according to Bosioc et al. [4]. In our case, an extra 2% jet discharge is required in order to obtain similar results with FFCT. This extra discharge is provided using an additional energy source. Therefore, the paper presents experimental investigation performed with FFCT with additional energy source. The experimental results obtained with this technique are compared against FFCT and the swirling flow with vortex rope, respectively.

  17. Effect of flow oscillations on axial energy transport in a porous material

    NASA Technical Reports Server (NTRS)

    Siegel, R.

    1987-01-01

    The effects of flow oscillations on axial energy diffusion in a porous medium, in which the flow is continuously disrupted by the irregularities of the porous structure, are analyzed. The formulation employs an internal heat transfer coefficient that couples the fluid and solid temperatures. The final relationship shows that the axial energy transport per unit cross-sectional area and time is directly proportional to the axial temperature gradient and the square of the maximum fluid displacement.

  18. Critical behavior in the inverse to forward energy transition in two-dimensional magnetohydrodynamic flow.

    PubMed

    Seshasayanan, Kannabiran; Alexakis, Alexandros

    2016-01-01

    We investigate the critical transition from an inverse cascade of energy to a forward energy cascade in a two-dimensional magnetohydrodynamic flow as the ratio of magnetic to mechanical forcing amplitude is varied. It is found that the critical transition is the result of two competing processes. The first process is due to hydrodynamic interactions and cascades the energy to the large scales. The second process couples small-scale magnetic fields to large-scale flows, transferring the energy back to the small scales via a nonlocal mechanism. At marginality the two cascades are both present and cancel each other. The phase space diagram of the transition is sketched.

  19. Fine powder flow under humid environmental conditions from the perspective of surface energy.

    PubMed

    Karde, Vikram; Ghoroi, Chinmay

    2015-05-15

    The influence of humidity on surface energetics and flow behavior of fine pharmaceutical powders was investigated. Amorphous and crystalline fine powders with hydrophilic (Corn starch and Avicel PH105) and hydrophobic (ibuprofen) nature were considered for this study. The surface energy was determined using surface energy analyzer and flow behavior was measured in terms of unconfined yield stress (UYS) using a shear tester. The study showed that unlike hydrophobic ibuprofen powder, surface energy and flow of hydrophilic excipient powders were affected by relative humidity (RH). The Lifshitz-van der Waals dispersive (γ(LW)) component of surface energy barely changed with varying RH for all pharmaceutical powders. For hydrophilic excipients, the specific component of surface energy (γ(SP)) was found to increase with increasing RH. Furthermore, for these excipients, flow deterioration at elevated RH was observed due to increased capillary bridge formation. Detailed analysis showed that γ(SP) component of surface energy can be an effective indicator for flow behavior of fine powders under varying humid conditions. The present study also brought out the existence of different regimes of probable interparticle forces which dictate the bulk flow behavior of fine hydrophilic powder under humid conditions.

  20. Techno-economic analysis for the evaluation of three UCG synthesis gas end use approaches

    NASA Astrophysics Data System (ADS)

    Nakaten, Natalie; Kempka, Thomas; Burchart-Korol, Dorota; Krawczyk, Piotr; Kapusta, Krzysztof; Stańczyk, Krzysztof

    2016-04-01

    Underground coal gasification (UCG) enables the utilization of coal reserves that are economically not exploitable because of complex geological boundary conditions. In the present study we investigate UCG as a potential economic approach for conversion of deep-seated coals into a synthesis gas and its application within three different utilization options. Related to geological boundary conditions and the chosen gasification agent, UCG synthesis gas composes of varying methane, hydrogen, nitrogen, carbon monoxide and carbon dioxide amounts. In accordance to its calorific value, the processed UCG synthesis gas can be utilized in different manners, as for electricity generation in a combined cycle power plant or for feedstock production making use of its various chemical components. In the present study we analyze UCG synthesis gas utilization economics in the context of clean electricity generation with an integrated carbon capture and storage process (CCS) as well as synthetic fuel and fertilizer production (Kempka et al., 2010) based on a gas composition achieved during an in situ UCG trial in the Wieczorek Mine. Hereby, we also consider chemical feedstock production in order to mitigate CO2 emissions. Within a sensitivity analysis of UCG synthesis gas calorific value variations, we produce a range of capital and operational expenditure bandwidths that allow for an economic assessment of different synthesis gas end use approaches. To carry out the integrated techno-economic assessment of the coupled systems and the sensitivity analysis, we adapted the techno-economic UCG-CCS model developed by Nakaten et al. (2014). Our techno-economic modeling results demonstrate that the calorific value has a high impact on the economics of UCG synthesis gas utilization. In the underlying study, the synthesis gas is not suitable for an economic competitive electricity generation, due to the relatively low calorific value of 4.5 MJ/Nm³. To be a profitable option for electricity

  1. Energy and materials flows in the iron and steel industry

    SciTech Connect

    Sparrow, F.T.

    1983-06-01

    Past energy-consumption trends and future energy-conservation opportunities are investigated for the nation's iron and steel industry. It is estimated that, in 1980, the industry directly consumed approximately 2.46 x 10/sup 15/ Btu of energy (roughly 3% of total US energy consumption) to produce 111 million tons of raw steel and to ship 84 million tons of steel products. Direct plus indirect consumption is estimated to be about 3.1 x 10/sup 15/ Btu. Of the set of conservation technologies identified, most are judged to be ready for commercialization if and when the industry's capital formation and profitability problems are solved and the gradual predicted increase in energy prices reduces the payback periods to acceptable levels.

  2. Investigations on sound energy decays and flows in a monumental mosque.

    PubMed

    Sü Gül, Zühre; Xiang, Ning; Çalışkan, Mehmet

    2016-07-01

    This work investigates the sound energy decays and flows in the Süleymaniye Mosque in İstanbul. This is a single-space superstructure having multiple domes. The study searches for the non-exponential sound energy decay characteristics. The effect of different material surfaces and volumetric contributions are investigated using acoustic simulations and in situ acoustical measurements. Sound energy decay rates are estimated by Bayesian decay analysis. The measured data reveal double- or triple-slope energy decay profiles within the superstructure. To shed light on the mechanism of energy exchanges resulting in multi-slope decay, spatial sound energy distributions and energy flow vectors are studied by diffusion equation model (DEM) simulations. The resulting sound energy flow vector maps highlight the contribution of a sound-reflective central dome contrasted with an absorptive carpeted floor in providing delayed energy feedback. In contrast, no multi-slope energy decay pattern is observed in DEM simulations with a bare marble floor, which generates a much more diffuse sound field than in the real situation with a carpeted floor. The results demonstrate that energy fragmentation, in support of the non-exponential energy decay profile, is due to both the sound absorption characteristics of materials and to their distributions, as well as to relations between the subvolumes of the mosque's interior. PMID:27475158

  3. Variational energy principle for compressible, baroclinic flow. 1: First and second variations of total kinetic action

    NASA Technical Reports Server (NTRS)

    Schmid, L. A.

    1977-01-01

    The case of a cold gas in the absence of external force fields is considered. Since the only energy involved is kinetic energy, the total kinetic action (i.e., the space-time integral of the kinetic energy density) should serve as the total free-energy functional in this case, and as such should be a local minimum for all possible fluctuations about stable flow. This conjecture is tested by calculating explicit, manifestly covariant expressions for the first and second variations of the total kinetic action in the context of Lagrangian kinematics. The general question of the correlation between physical stability and the convexity of any action integral that can be interpreted as the total free-energy functional of the flow is discussed and illustrated for the cases of rectillinear and rotating shearing flows.

  4. Energy and matter flows in a plasma focus discharge

    NASA Astrophysics Data System (ADS)

    Vikhrev, V. V.; Suslin, S. V.

    2016-01-01

    The Plasma Focus is a type of z-pinch that is widely used for both basic research and applied tasks, e.g., as materials modification or research on intense plasma flows. Although the basic mechanisms of z-pinch compression are well-known, many of the processes that occur in the plasma focus have received less attention. This article is devoted to the study of plasma jets and some of its consequences in plasma focus discharges.

  5. Drag reduction by polymers in turbulent channel flows: Energy redistribution between invariant empirical modes.

    PubMed

    De Angelis, Elisabetta; Casciola, Carlo M; L'vov, Victor S; Piva, Renzo; Procaccia, Itamar

    2003-05-01

    We address the phenomenon of drag reduction by a dilute polymeric additive to turbulent flows, using direct numerical simulations (DNS) of the FENE-P model of viscoelastic flows. It had been amply demonstrated that these model equations reproduce the phenomenon, but the results of DNS were not analyzed so far with the goal of interpreting the phenomenon. In order to construct a useful framework for the understanding of drag reduction we initiate in this paper an investigation of the most important modes that are sustained in the viscoelastic and Newtonian turbulent flows, respectively. The modes are obtained empirically using the Karhunen-Loéve decomposition, allowing us to compare the most energetic modes in the viscoelastic and Newtonian flows. The main finding of the present study is that the spatial profile of the most energetic modes is hardly changed between the two flows. What changes is the energy associated with these modes, and their relative ordering in the decreasing order from the most energetic to the least. Modes that are highly excited in one flow can be strongly suppressed in the other, and vice versa. This dramatic energy redistribution is an important clue to the mechanism of drag reduction as is proposed in this paper. In particular, there is an enhancement of the energy containing modes in the viscoelastic flow compared to the Newtonian one; drag reduction is seen in the energy containing modes rather than the dissipative modes, as proposed in some previous theories.

  6. Analysis of atmospheric flow over a surface protrusion using the turbulence kinetic energy equation

    NASA Technical Reports Server (NTRS)

    Frost, W.; Harper, W. L.; Fichtl, G. H.

    1975-01-01

    Atmospheric flow fields resulting from a semi-elliptical surface obstruction in an otherwise horizontally homogeneous statistically stationary flow are modelled with the boundary-layer/Boussinesq-approximation of the governing equation of fluid mechanics. The turbulence kinetic energy equation is used to determine the dissipative effects of turbulent shear on the mean flow. Mean-flow results are compared with those given in a previous paper where the same problem was attacked using a Prandtl mixing-length hypothesis. Iso-lines of turbulence kinetic energy and turbulence intensity are plotted in the plane of the flow. They highlight regions of high turbulence intensity in the stagnation zone and sharp gradients in intensity along the transition from adverse to favourable pressure gradient.

  7. Fluctuation-induced shear flow and energy transfer in plasma interchange turbulence

    SciTech Connect

    Li, B.; Sun, C. K.; Wang, X. Y.; Zhou, A.; Wang, X. G.; Ernst, D. R.

    2015-11-15

    Fluctuation-induced E × B shear flow and energy transfer for plasma interchange turbulence are examined in a flux-driven system with both closed and open magnetic field lines. The nonlinear evolution of interchange turbulence shows the presence of two confinement regimes characterized by low and high E × B flow shear. In the first regime, the large-scale turbulent convection is dominant and the mean E × B shear flow is at a relatively low level. By increasing the heat flux above a certain threshold, the increased turbulent intensity gives rise to the transfer of energy from fluctuations to mean E × B flows. As a result, a transition to the second regime occurs, in which a strong mean E × B shear flow is generated.

  8. Mass, momentum and energy flow from an MPD accelerator. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Cory, J. S.

    1971-01-01

    The mass, momentum, and energy flows are measured over a current range of 8 to 50 kA and inlet mass flows of 2 to 36q/sec of argon. The momentum flux profile indicates that the accelerator produces a uniform, 2-inch diameter axial jet at the anode which expands into a Gaussian profile at an axial station 11 inches from the anode. The electromagnetic component of the thrust is found to follow the familiar quadratic dependence on arc current, while a more complex empirical relation is needed to correlate the gasdynamic contribution with the current and mass flow rate. Using available time-of-flight velocity profiles at a current of 16 kA and a mass flow of 5.9 g/sec, calculated flux profiles of mass and kinetic energy exhibit a tendency for some fraction of the inlet mass flow to leak out at a low velocity around the central high velocity core.

  9. UNDERSTANDING FLOW OF ENERGY IN BUILDINGS USING MODAL ANALYSIS METHODOLOGY

    SciTech Connect

    John Gardner; Kevin Heglund; Kevin Van Den Wymelenberg; Craig Rieger

    2013-07-01

    It is widely understood that energy storage is the key to integrating variable generators into the grid. It has been proposed that the thermal mass of buildings could be used as a distributed energy storage solution and several researchers are making headway in this problem. However, the inability to easily determine the magnitude of the building’s effective thermal mass, and how the heating ventilation and air conditioning (HVAC) system exchanges thermal energy with it, is a significant challenge to designing systems which utilize this storage mechanism. In this paper we adapt modal analysis methods used in mechanical structures to identify the primary modes of energy transfer among thermal masses in a building. The paper describes the technique using data from an idealized building model. The approach is successfully applied to actual temperature data from a commercial building in downtown Boise, Idaho.

  10. Emissions from residential combustion considering end-uses and spatial constraints: Part II, emission reduction scenarios

    NASA Astrophysics Data System (ADS)

    Winijkul, Ekbordin; Bond, Tami C.

    2016-01-01

    Cooking, heating, and other activities in the residential sector are major sources of indoor and outdoor air pollution, especially when solid fuels are used to provide energy. Because of their deleterious effects on the atmosphere and human health, multinational strategies to reduce emissions have been proposed. This study examines the effects of some possible policies, considering realistic factors that constrain mitigation: end-uses, spatial constraints involving proximity to forest or electricity, existing technology, and assumptions about user behavior. Reduction scenarios are applied to a year-2010, spatially distributed baseline of emissions of particulate matter, black carbon, organic carbon, nitrogen oxides, methane, non-methane hydrocarbons, carbon monoxide, and carbon dioxide. Scenarios explored are: (1) cleanest current stove, where we assume that existing technology in each land type is applied to burn existing fuels; (2) stove standards, where we assume that stoves are designed to meet performance standards; and (3) clean fuels, where users adopt the cleanest fuels plausible in each land type. We assume that people living in forest access areas continue to use wood regardless of available fuels, so the clean-fuels scenario leads to a reduction in emissions of 18-25%, depending on the pollutant, across the study region. Cleaner stoves preferentially affect land types with forest access, where about half of the fuel is used; emission reductions range from 25 to 82%, depending on the pollutant. If stove performance standards can be met, particulate matter emissions are reduced by 62% for the loosest standards and 95% for the tightest standards, and carbon monoxide is reduced by 40% and 62% for the loosest and tightest standards. Reductions in specific regions and countries depend on the existing fuel mixture and the population division among land types, and are explored for Latin America, Africa, East Asia, South Asia, and Southeast Asia.

  11. Generalization and extension of the law of acoustic energy conservation in a nonuniform flow

    NASA Technical Reports Server (NTRS)

    Myers, M. K.

    1986-01-01

    An exact conservation equation is derived which generalizes the familiar acoustic energy equations. The new relation is valid for arbitrary disturbances to a viscous, compressible flow. It is suggested by a development of the acoustic energy equation by means of a regular perturbation expansion of the general energy equation of fluid mechanics. A perturbation energy density and flux are defined and identified as the exact physical quantities whose leading order perturbation representations are the usual acoustic energy density and flux. The conservation equation governing the perturbation energy quantities is shown to yield previously known results for several special cases.

  12. Local expansion flows of galaxies: quantifying acceleration effect of dark energy

    NASA Astrophysics Data System (ADS)

    Chernin, A. D.; Teerikorpi, P.

    2013-08-01

    The nearest expansion flow of galaxies observed around the Local group is studied as an archetypical example of the newly discovered local expansion flows around groups and clusters of galaxies in the nearby Universe. The flow is accelerating due to the antigravity produced by the universal dark energy background. We introduce a new acceleration measure of the flow which is the dimensionless ``acceleration parameter" Q (x) = x - x-2 depending on the normalized distance x only. The parameter is zero at the zero-gravity distance x = 1, and Q(x) ∝ x, when x ≫ 1. At the distance x = 3, the parameter Q = 2.9. Since the expansion flows have a self-similar structure in normalized variables, we expect that the result is valid as well for all the other expansion flows around groups and clusters of galaxies on the spatial scales from ˜ 1 to ˜ 10 Mpc everywhere in the Universe.

  13. Transient radiative energy transfer in incompressible laminar flows

    NASA Technical Reports Server (NTRS)

    Tiwari, S. N.; Singh, D. J.

    1987-01-01

    Analysis and numerical procedures are presented to investigate the transient radiative interactions of nongray absorbing-emitting species in laminar fully-developed flows between two parallel plates. The particular species considered are OH, CO, CO2, and H2O and different mixtures of these. Transient and steady-state results are obtained for the temperaure distribution and bulk temperature for different plate spacings, wall temperatures, and pressures. Results, in general, indicate that the rate of radiative heating can be quite high during earlier times. This information is useful in designing thermal protection systems for transient operations.

  14. Aircraft energy efficiency laminar flow control wing design study

    NASA Technical Reports Server (NTRS)

    Bonner, T. F., Jr.; Pride, J. D., Jr.; Fernald, W. W.

    1977-01-01

    An engineering design study was performed in which laminar flow control (LFC) was integrated into the wing of a commercial passenger transport aircraft. A baseline aircraft configuration was selected and the wing geometry was defined. The LFC system, with suction slots, ducting, and suction pumps was integrated with the wing structure. The use of standard aluminum technology and advanced superplastic formed diffusion bonded titanium technology was evaluated. The results of the design study show that the LFC system can be integrated with the wing structure to provide a structurally and aerodynamically efficient wing for a commercial transport aircraft.

  15. Relationships among the energy, emergy, and money flows of the United States from 1900 to 2011.

    EPA Science Inventory

    Energy Systems Language models of the resource base for the U.S. economy and of economic exchange were used, respectively, (1) to show how energy consumption and emergy use contribute to real and nominal gross domestic product (GDP) and (2) to propose a model of coupled flows tha...

  16. Determination of the Arrhenius Activation Energy Using a Temperature-Programmed Flow Reactor.

    ERIC Educational Resources Information Center

    Chan, Kit-ha C.; Tse, R. S.

    1984-01-01

    Describes a novel method for the determination of the Arrhenius activation energy, without prejudging the validity of the Arrhenius equation or the concept of activation energy. The method involves use of a temperature-programed flow reactor connected to a concentration detector. (JN)

  17. Fluctuating kinetic energy budget during homogeneous flow of a fluid solid mixture

    SciTech Connect

    Liljegren, L.M.; Foslein, W.

    1996-01-01

    Ensemble-averaging theorems are applied to derive transport equations for the fluctuating kinetic energy of a particulate mixture consisting of a continuous fluid and solid particles. The evolution of fluctuating kinetic energy in a homogeneous flow is examined and discussed. {copyright} {ital 1996 American Institute of Physics.}

  18. Vibration energy harvesting in a small channel fluid flow using piezoelectric transducer

    NASA Astrophysics Data System (ADS)

    Hassan, Md. Mehedi; Hossain, Md. Yeam; Mazumder, Rakib; Rahman, Roussel; Rahman, Md. Ashiqur

    2016-07-01

    This work is aimed at developing a way to harvest energy from a fluid stream with the application of piezoelectric transducers in a small channel. In this COMSOL Multiphysics based simulation study, it is attempted to harvest energy from the abundant renewable source of energy available in the form of kinetic energy of naturally occurring flow of fluids. The strategy involves harnessing energy from a fluid-actuator through generation of couples, eddies and vortices, resulting from the stagnation and separation of flow around a semi-circular bluff-body attached to a cantilever beam containing a piezoceramic layer. Fluctuation of fluidic pressure impulse on the beam due to vortex shedding and varying lift forces causes the flexible cantilever beam to oscillate in the direction normal to the fluid flow in a periodic manner. The periodic application and release of a mechanical strain upon the beam effected a generation of electric potential within the piezoelectric layer, thus enabling extraction of electrical energy from the kinetic energy of the fluid. The piezoelectric material properties and transducer design are kept unchanged throughout the study, whereas the configuration is tested with different fluids and varying flow characteristics. The size and geometry of the obstructing entity are systematically varied to closely inspect the output from different iterations and for finding the optimum design parameters. The intermittent changes in the generated forces and subsequent variation in the strain on the beam are also monitored to find definitive relationship with the electrical energy output.

  19. Relationships Among the Energy, Emergy, and Money Flows of the United States From 1900 to 2011

    EPA Science Inventory

    In this paper, we examine the relationships among the energy, emergy, and money flows of the United States from 1900 to 2011. To establish a theoretical basis for understanding these relationships, Energy Systems Language models of the resource base for the World System and of e...

  20. Energy and materials flows in the copper industry

    SciTech Connect

    Gaines, L.L.

    1980-12-01

    The copper industry comprises both the primary copper industry, which produces 99.9%-pure copper from copper ore, and the secondary copper industry, which salvages and recycles copper-containing scrap metal to extract pure copper or copper alloys. The United States uses about 2 million tons of copper annually, 60% of it for electrical applications. Demand is expected to increase less than 4% annually for the next 20 years. The primary copper industry is concentrated in the Southwest; Arizona produced 66% of the 1979 total ore output. Primary production uses about 170 x 10/sup 12/ Btu total energy annually (about 100 x 10/sup 6/ Btu/ton pure copper produced from ore). Mining and milling use about 60% of the total consumption, because low-grade ore (0.6% copper) is now being mined. Most copper is extracted by smelting sulfide ores, with concomitant production of sulfur dioxide. Clean air regulations will require smelters to reduce sulfur emissions, necessitating smelting process modifications that could also save 20 x 10/sup 12/ Btu (10 x 10/sup 6/ Btu/ton of copper) in smelting energy. Energy use in secondary copper production averages 20 x 10/sup 6/ Btu/ton of copper. If all copper products were recycled, instead of the 30% now salvaged, the energy conservation potential would be about one-half the total energy consumption of the primary copper industry.

  1. Energy Harvesting from Fluid Flow in Water Pipelines for Smart Metering Applications

    NASA Astrophysics Data System (ADS)

    Hoffmann, D.; Willmann, A.; Göpfert, R.; Becker, P.; Folkmer, B.; Manoli, Y.

    2013-12-01

    In this paper a rotational, radial-flux energy harvester incorporating a three-phase generation principle is presented for converting energy from water flow in domestic water pipelines. The energy harvester together with a power management circuit and energy storage is used to power a smart metering system installed underground making it independent from external power supplies or depleting batteries. The design of the radial-flux energy harvester is adapted to the housing of a conventional mechanical water flow meter enabling the use of standard components such as housing and impeller. The energy harvester is able to generate up to 720 mW when using a flow rate of 20 l/min (fully opened water tab). A minimum flow rate of 3 l/min is required to get the harvester started. In this case a power output of 2 mW is achievable. By further design optimization of the mechanical structure including the impeller and magnetic circuit the threshold flow rate can be further reduced.

  2. Quantifying the influence of environmental and water conservation attitudes on household end use water consumption.

    PubMed

    Willis, Rachelle M; Stewart, Rodney A; Panuwatwanich, Kriengsak; Williams, Philip R; Hollingsworth, Anna L

    2011-08-01

    Within the research field of urban water demand management, understanding the link between environmental and water conservation attitudes and observed end use water consumption has been limited. Through a mixed method research design incorporating field-based smart metering technology and questionnaire surveys, this paper reveals the relationship between environmental and water conservation attitudes and a domestic water end use break down for 132 detached households located in Gold Coast city, Australia. Using confirmatory factor analysis, attitudinal factors were developed and refined; households were then categorised based on these factors through cluster analysis technique. Results indicated that residents with very positive environmental and water conservation attitudes consumed significantly less water in total and across the behaviourally influenced end uses of shower, clothes washer, irrigation and tap, than those with moderately positive attitudinal concern. The paper concluded with implications for urban water demand management planning, policy and practice.

  3. Algebraic structure of general electromagnetic fields and energy flow

    SciTech Connect

    Hacyan, Shahen

    2011-08-15

    Highlights: > Algebraic structure of general electromagnetic fields in stationary spacetime. > Eigenvalues and eigenvectors of the electomagnetic field tensor. > Energy-momentum in terms of eigenvectors and Killing vector. > Explicit form of reference frame with vanishing Poynting vector. > Application of formalism to Bessel beams. - Abstract: The algebraic structures of a general electromagnetic field and its energy-momentum tensor in a stationary space-time are analyzed. The explicit form of the reference frame in which the energy of the field appears at rest is obtained in terms of the eigenvectors of the electromagnetic tensor and the existing Killing vector. The case of a stationary electromagnetic field is also studied and a comparison is made with the standard short-wave approximation. The results can be applied to the general case of a structured light beams, in flat or curved spaces. Bessel beams are worked out as example.

  4. Energy Flow in the Magnetosphere-Ionosphere-Thermosphere (MIT) System

    NASA Astrophysics Data System (ADS)

    Huang, C. Y.; Huang, Y.; Su, Y. J.; Sutton, E. K.; Hairston, M. R.

    2015-12-01

    The conventional model of energy input and dissipation in the IT system assumes that the auroral zone is the primary locus for these processes. Recent work has revealed that, contrary to this traditional view, the polar cap can play a significant role in energy transfer during magnetic storms. DMSP measurements of DC Poynting flux shows high levels of electromagnetic energy entering the polar cap at all local times (LTs) in both hemispheres during storms. An analysis of ion temperature observations at DMSP altitudes shows that the largest temperature increases occur at polar latitudes during magnetic activity. Finally, observations of neutral densities from the CHAMP, GRACE and GOCE spacecraft show that the highest frequency of occurrence of heated neutrals occurs close to the poles in both hemispheres. These results demand a revision of the standard paradigm for MIT coupling.

  5. Valuing uncertain cash flows from investments that enhance energy efficiency.

    PubMed

    Abadie, Luis M; Chamorro, José M; González-Eguino, Mikel

    2013-02-15

    There is a broad consensus that investments to enhance energy efficiency quickly pay for themselves in lower energy bills and spared emission allowances. However, investments that at first glance seem worthwhile usually are not undertaken. One of the plausible, non-excluding explanations is the numerous uncertainties that these investments face. This paper deals with the optimal time to invest in an energy efficiency enhancement at a facility already in place that consumes huge amounts of a fossil fuel (coal) and operates under carbon constraints. We follow the Real Options approach. Our model comprises three sources of uncertainty following different stochastic processes which allows for application in a broad range of settings. We assess the investment option by means of a three-dimensional binomial lattice. We compute the trigger investment cost, i.e., the threshold level below which immediate investment would be optimal. We analyze the major drivers of this decision thus aiming at the most promising policies in this regard.

  6. Energy flow in non-equilibrium conformal field theory

    NASA Astrophysics Data System (ADS)

    Bernard, Denis; Doyon, Benjamin

    2012-09-01

    We study the energy current and its fluctuations in quantum gapless 1d systems far from equilibrium modeled by conformal field theory, where two separated halves are prepared at distinct temperatures and glued together at a point contact. We prove that these systems converge towards steady states, and give a general description of such non-equilibrium steady states in terms of quantum field theory data. We compute the large deviation function, also called the full counting statistics, of energy transfer through the contact. These are universal and satisfy fluctuation relations. We provide a simple representation of these quantum fluctuations in terms of classical Poisson processes whose intensities are proportional to Boltzmann weights.

  7. Vibrational energy flow in the villin headpiece subdomain: Master equation simulations

    SciTech Connect

    Leitner, David M. E-mail: stock@physik.uni-freiburg.de; Buchenberg, Sebastian; Brettel, Paul; Stock, Gerhard E-mail: stock@physik.uni-freiburg.de

    2015-02-21

    We examine vibrational energy flow in dehydrated and hydrated villin headpiece subdomain HP36 by master equation simulations. Transition rates used in the simulations are obtained from communication maps calculated for HP36. In addition to energy flow along the main chain, we identify pathways for energy transport in HP36 via hydrogen bonding between residues quite far in sequence space. The results of the master equation simulations compare well with all-atom non-equilibrium simulations to about 1 ps following initial excitation of the protein, and quite well at long times, though for some residues we observe deviations between the master equation and all-atom simulations at intermediate times from about 1–10 ps. Those deviations are less noticeable for hydrated than dehydrated HP36 due to energy flow into the water.

  8. Anticipation Driving Behavior and Related Reduction of Energy Consumption in Traffic Flow

    NASA Astrophysics Data System (ADS)

    Shi, Wei; Wei, Yan-Fang; Song, Tao; Dai, Shi-Qiang; Dong, Li-Yun

    In view that drivers would pay attention to the variation of headway on roads, an extended optimal velocity model is proposed by considering anticipation driving behavior. A stability criterion is given through linear stability analysis of traffic flows. The mKdV equation is derived with the reductive perturbation method for headway evolution which could be used to describe the stop-and-go traffic phenomenon. The results show a good effect of anticipation driving behavior on the stabilization of car flows and the anticipation driving behavior can improve the numerical stability of the model as well. In addition, the fluctuation of kinetic energy and the consumption of average energy in congested traffic flows are systematically analyzed. The results show that the reasonable level of anticipation driving behavior can save energy consumption in deceleration process effectively and lead to an associated relation like a "bow-tie" between the energy-saving and the value of anticipation factor.

  9. Non-invasive energy meter for fixed and variable flow systems

    DOEpatents

    Menicucci, David F.; Black, Billy D.

    2005-11-01

    An energy metering method and apparatus for liquid flow systems comprising first and second segments of one or more conduits through which a liquid flows, comprising: attaching a first temperature sensor for connection to an outside of the first conduit segment; attaching a second temperature sensor for connection to an outside of the second conduit segment; via a programmable control unit, receiving data from the sensors and calculating energy data therefrom; and communicating energy data from the meter; whereby the method and apparatus operate without need to temporarily disconnect or alter the first or second conduit segments. The invention operates with both variable and fixed flow systems, and is especially useful for both active and passive solar energy systems.

  10. Kinematic, Dynamic, and Energy Characteristics of Diastolic Flow in the Left Ventricle

    PubMed Central

    Khalafvand, Seyed Saeid; Hung, Tin-Kan; Ng, Eddie Yin-Kwee; Zhong, Liang

    2015-01-01

    Blood flow characteristics in the normal left ventricle are studied by using the magnetic resonance imaging, the Navier-Stokes equations, and the work-energy equation. Vortices produced during the mitral valve opening and closing are modeled in a two-dimensional analysis and correlated with temporal variations of the Reynolds number and pressure drop. Low shear stress and net pressures on the mitral valve are obtained for flow acceleration and deceleration. Bernoulli energy flux delivered to blood from ventricular dilation is practically balanced by the energy influx and the rate change of kinetic energy in the ventricle. The rates of work done by shear and energy dissipation are small. The dynamic and energy characteristics of the 2D results are comparable to those of a 3D model. PMID:26417381

  11. Active flow control integrated diffuser (afcid) for increased energy efficiency in variable air volume systems

    NASA Astrophysics Data System (ADS)

    Van Der Schijff, Hermanus P.

    Variable air volume (VAV) air terminals are designed to save energy by reducing airflow into a given space based on occupancy and required load. Systems are typically designed to operate at peak load, however as load is reduced, performance is compromised due to inadequate throw. As a result, fans are installed to adjust for the losses, negating many of the energy savings. Additionally flow is vectored by the use of vanes, a basic passive type of flow control. An experimental investigation was performed to study the application of flow control on that of a HVAC diffuser using synthetic jets distributed evenly along the diffuser edge parallel to the flow field. The study was conducted on a 1:3 scale typical office space (150 ft2), which included a simulated scale HVAC system supplied by compressed air. Two different jet blowing ratios were investigated for system loads of 60% and 90%. The flow field was established using hot wire anemometry and Particle Image Velocimetry (PIV). This study demonstrates the effectiveness of synthetic jet based active flow control at controlling airflow, showing ability to affect throw parameters for changing flow rates within the test chamber. Vectoring of up to 20% and improvement in jet spread of 200% was demonstrated. The use of such devices has the potential to improve air quality and air distribution in building while simultaneously lowering energy demands of HVAC systems.

  12. Energy flow in a hadronic cascade: Application to hadroncalorimetry

    SciTech Connect

    Groom, Donald E.

    2006-05-17

    The hadronic cascade description developed in an earlierpaper is extended to the response of an idealized fine-sampling hadroncalorimeter. Calorimeter response is largely determined by the transferof energy E_e from the hadronic to the electromagnetic sector via \\pi0production. Fluctuations in this quantity produce the "constant term" inhadron calorimeter resolution. The increase of its fractional mean, f_\\rmem^0= \\vevE_e/E, with increasing incident energy E causes the energydependence of the \\pi/e ratio in a noncompensating calorimeter. The meanhadronic energy fraction, f_h0 = 1-f_\\rm em0, was shown to scaleverynearly as a power law in E: f_h0 = (E/E_0)m-1, where E_0\\approx1~;GeV forpions, and m\\approx0.83. It follows that \\pi/e=1-(1-h/e)(E/E_0)m-1, whereelectromagnetic and hadronic energy deposits are detected withefficiencies e and h, respectively. Fluctuations in these quantities,along with sampling fluctuations, are in corporated to give an overallunderstanding of resolution, which is different from the usual treatmentsin interesting ways. The conceptual framework is also extended to theresponse to jets and the difference between pi and presponse.

  13. Spectral wave flow attenuation within submerged canopies: Implications for wave energy dissipation

    NASA Astrophysics Data System (ADS)

    Lowe, Ryan J.; Falter, James L.; Koseff, Jeffrey R.; Monismith, Stephen G.; Atkinson, Marlin J.

    2007-05-01

    Communities of benthic organisms can form very rough surfaces (canopies) on the seafloor. Previous studies have shown that an oscillatory flow induced by monochromatic surface waves will drive more flow inside a canopy than a comparable unidirectional current. This paper builds on these previous studies by investigating how wave energy is attenuated within canopies under spectral wave conditions, or random wave fields defined by many frequencies. A theoretical model is first developed to predict how flow attenuation within a canopy varies among the different wave components and predicts that shorter-period components will generally be more effective at driving flow within a canopy than longer-period components. To investigate the model performance, a field experiment was conducted on a shallow reef flat in which flow was measured both inside and above a model canopy array. Results confirm that longer-period components in the spectrum are significantly more attenuated than shorter-period components, in good agreement with the model prediction. This paper concludes by showing that the rate at which wave energy is dissipated by a canopy is closely linked to the flow structure within the canopy. Under spectral wave conditions, wave energy within a model canopy array is dissipated at a greater rate among the shorter-period wave components. These observations are consistent with previous observations of how wave energy is dissipated by the bottom roughness of a coral reef.

  14. A flow microcalorimeter system for the measurement of dynamic energy variables of isolated perfused hearts.

    PubMed

    Niesler, R A; Axon, D W

    1981-11-01

    An isothermic flow microcalorimeter system for fluid rates of 1-50 cm3 min -1 has been developed to measure the total heat flow produced by isolated perfused small animal hearts and its rate of change. The heat, which is absorbed by the perfusion fluid flowing through the coronary capillary system, is detected by passing the coronary effluent through a plate heat exchanger mounted in intimate contact with the internal surface of a gradient layer calorimeter. By employing electrical calibration, this heat flow detector gives a precision of +/- 0.2 m W for average effluent rates of about 15 cm3 min-1. The method provides direct comparison of the biologically produced heat flow with electrically generated energy flows. The response time to step changes in heat flow is 1 min to 90% of the total change. Possible systematic errors are analysed and quantified, using a heart bypass flow technique and a thermoelectric differential temperature meter. The accuracy of the measurement of constant heat sources with the complete system over the range of 5-40 mW is +/- 2% for fluid rates up to 40 cm3 min-1. Measurements with small rat hearts have given absolute values between 17 and 36 mW measured with an accuracy of +/- 3%. The rate of total myocardial energy turnover can be studied with the system.

  15. Vibrational energy flow models for the Rayleigh-Love and Rayleigh-Bishop rods

    NASA Astrophysics Data System (ADS)

    Han, Ju-Bum; Hong, Suk-Yoon; Song, Jee-Hun; Kwon, Hyun-Wung

    2014-01-01

    Energy Flow Analysis (EFA) has been developed to predict the vibrational energy density of the system structures in the medium-to-high frequency range. The elementary longitudinal wave theory is often used to describe the longitudinal vibration of a slender rod. However, for relatively large diameter rods or high frequency ranges, the elementary longitudinal wave theory is inaccurate because the lateral motions are not taken into account. In this paper, vibrational energy flow models are developed to analyze the longitudinally vibrating Rayleigh-Love rod considering the effect of lateral inertia, and the Rayleigh-Bishop rod considering the effect not only of the lateral inertia but also of the shear stiffness. The derived energy governing equations are second-order differential equations which predict the time and space averaged energy density and active intensity distributions in a rod. To verify the accuracy of the developed energy flow models, various numerical analyses are performed for a rod and coupled rods. Also, the EFA results for the Rayleigh-Love and Rayleigh-Bishop rods are compared with the analytical solutions for these models, the traditional energy flow solutions, and the analytical solutions for the classical rod.

  16. The Impact of Neighbourhood Density on the Energy Demand of Passive Houses and on Potential Energy Sources from the Waste Flows and Solar Energy

    NASA Astrophysics Data System (ADS)

    Stupka, Robert

    This study demonstrates how the density of a neighbourhood affects its energy demand, metabolism (energy and material flows) and its ability to produce its own energy. Single-family detached houses and row townhouses were each modeled using passive solar housing guidelines with the DesignBuilder building energy simulation software. Energy demand is then modeled within neighbourhoods at two densities based on south facing windows fully un-shaded at 9:00 am, and 12:00 pm solar time on Dec. 21. The neighbourhood metabolisms were then calculated based on location and density. The potential energy supply was evaluated from the spatial characteristics of the neighbourhood (for solar) and the metabolism (municipal solid waste and wastewater flows.) The potential energy demand and supply are then compared for the varying building types and densities to determine the sensitivity of the energy supply and demand relationships.

  17. Energy flow and functional compensation in Great Basin small mammals under natural and anthropogenic environmental change

    PubMed Central

    Terry, Rebecca C.; Rowe, Rebecca J.

    2015-01-01

    Research on the ecological impacts of environmental change has primarily focused at the species level, leaving the responses of ecosystem-level properties like energy flow poorly understood. This is especially so over millennial timescales inaccessible to direct observation. Here we examine how energy flow within a Great Basin small mammal community responded to climate-driven environmental change during the past 12,800 y, and use this baseline to evaluate responses observed during the past century. Our analyses reveal marked stability in energy flow during rapid climatic warming at the terminal Pleistocene despite dramatic turnover in the distribution of mammalian body sizes and habitat-associated functional groups. Functional group turnover was strongly correlated with climate-driven changes in regional vegetation, with climate and vegetation change preceding energetic shifts in the small mammal community. In contrast, the past century has witnessed a substantial reduction in energy flow caused by an increase in energetic dominance of small-bodied species with an affinity for closed grass habitats. This suggests that modern changes in land cover caused by anthropogenic activities—particularly the spread of nonnative annual grasslands—has led to a breakdown in the compensatory dynamics of energy flow. Human activities are thus modifying the small mammal community in ways that differ from climate-driven expectations, resulting in an energetically novel ecosystem. Our study illustrates the need to integrate across ecological and temporal scales to provide robust insights for long-term conservation and management. PMID:26170294

  18. Energy flow and functional compensation in Great Basin small mammals under natural and anthropogenic environmental change.

    PubMed

    Terry, Rebecca C; Rowe, Rebecca J

    2015-08-01

    Research on the ecological impacts of environmental change has primarily focused at the species level, leaving the responses of ecosystem-level properties like energy flow poorly understood. This is especially so over millennial timescales inaccessible to direct observation. Here we examine how energy flow within a Great Basin small mammal community responded to climate-driven environmental change during the past 12,800 y, and use this baseline to evaluate responses observed during the past century. Our analyses reveal marked stability in energy flow during rapid climatic warming at the terminal Pleistocene despite dramatic turnover in the distribution of mammalian body sizes and habitat-associated functional groups. Functional group turnover was strongly correlated with climate-driven changes in regional vegetation, with climate and vegetation change preceding energetic shifts in the small mammal community. In contrast, the past century has witnessed a substantial reduction in energy flow caused by an increase in energetic dominance of small-bodied species with an affinity for closed grass habitats. This suggests that modern changes in land cover caused by anthropogenic activities--particularly the spread of nonnative annual grasslands--has led to a breakdown in the compensatory dynamics of energy flow. Human activities are thus modifying the small mammal community in ways that differ from climate-driven expectations, resulting in an energetically novel ecosystem. Our study illustrates the need to integrate across ecological and temporal scales to provide robust insights for long-term conservation and management. PMID:26170294

  19. Valuing uncertain cash flows from investments that enhance energy efficiency.

    PubMed

    Abadie, Luis M; Chamorro, José M; González-Eguino, Mikel

    2013-02-15

    There is a broad consensus that investments to enhance energy efficiency quickly pay for themselves in lower energy bills and spared emission allowances. However, investments that at first glance seem worthwhile usually are not undertaken. One of the plausible, non-excluding explanations is the numerous uncertainties that these investments face. This paper deals with the optimal time to invest in an energy efficiency enhancement at a facility already in place that consumes huge amounts of a fossil fuel (coal) and operates under carbon constraints. We follow the Real Options approach. Our model comprises three sources of uncertainty following different stochastic processes which allows for application in a broad range of settings. We assess the investment option by means of a three-dimensional binomial lattice. We compute the trigger investment cost, i.e., the threshold level below which immediate investment would be optimal. We analyze the major drivers of this decision thus aiming at the most promising policies in this regard. PMID:23295678

  20. Energy harvesting by means of flow-induced vibrations on aerospace vehicles

    NASA Astrophysics Data System (ADS)

    Li, Daochun; Wu, Yining; Da Ronch, Andrea; Xiang, Jinwu

    2016-10-01

    This paper reviews the design, implementation, and demonstration of energy harvesting devices that exploit flow-induced vibrations as the main source of energy. Starting with a presentation of various concepts of energy harvesters that are designed to benefit from a general class of flow-induced vibrations, specific attention is then given at those technologies that may offer, today or in the near future, a potential benefit to extend the operational capabilities and to monitor critical parameters of unmanned aerial vehicles. Various phenomena characterized by flow-induced vibrations are discussed, including limit cycle oscillations of plates and wing sections, vortex-induced and galloping oscillations of bluff bodies, vortex-induced vibrations of downstream structures, and atmospheric turbulence and gusts. It was found that linear or linearized modeling approaches are commonly employed to support the design phase of energy harvesters. As a result, highly nonlinear and coupled phenomena that characterize flow-induced vibrations are neglected in the design process. The Authors encourage a shift in the current design paradigm: considering coupled nonlinear phenomena, and adequate modeling tools to support their analysis, from a design limitation to a design opportunity. Special emphasis is placed on identifying designs and implementations applicable to aircraft configurations. Application fields of flow-induced vibrations-based energy harvesters are discussed including power supply for wireless sensor networks and simultaneous energy harvest and control. A large body of work on energy harvesters is included in this review journal. Whereas most of the references claim direct applications to unmanned aerial vehicles, it is apparent that, in most of the cases presented, the working principles and characteristics of the energy harvesters are incompatible with any aerospace applications. Finally, the challenges that hold back the integration of energy harvesting

  1. Multichannel readout ASIC design flow for high energy physics and cosmic rays experiments

    NASA Astrophysics Data System (ADS)

    Voronin, A.; Malankin, E.

    2016-02-01

    In the large-scale high energy physics and astrophysics experiments multi-channel readout application specific integrated circuits (ASICs) are widely used. The ASICs for such experiments are complicated systems, which usually include both analog and digital building blocks. The complexity and large number of channels in such ASICs require the proper methodological approach to their design. The paper represents the mixed-signal design flow of the ASICs for high energy physics and cosmic rays experiments. This flow was successfully embedded to the development of the read-out ASIC prototype for the muon chambers of the CBM experiment. The approach was approved in UMC CMOS MMRF 180 nm process. The design flow enable to analyse the mixed-signal system operation on the different levels: functional, behavioural, schematic and post layout including parasitic elements. The proposed design flow allows reducing the simulation period and eliminating the functionality mismatches on the very early stage of the design.

  2. Preferential flow in connected soil structures and the principle of "maximum energy dissipation": A thermodynamic perspective

    NASA Astrophysics Data System (ADS)

    Zehe, E.; Blume, T.; Bloeschl, G.

    2009-04-01

    Helmholtz free energy. Thermodynamic equilibrium is a state of minimum free energy. The latter is determined by potential energy and capillary energy in soil, which in turn strongly depends on soil moisture, pore size distribution and depth to groundwater. The objective of this study is threefold. First, we will introduce the necessary theoretical background. Second we suggest ? based on simulations with a physically based hydrological model ? that water flow in connected preferential pathways assures a faster relaxation towards thermodynamic equilibrium through a faster drainage of ?excess water? and a faster redistribution of ?capillary water? within the soil. The latter process is of prime importance in case of cohesive soils where the pore size distribution is dominated by medium and small pores. Third, an application of a physically based hydrological model to predict water flow and runoff response from a pristine catchment in the Chilenean Andes underpins this hypothesis. Behavioral model structures that allow a good match of the observed hydrographs turned out to be most efficient in dissipating free energy by means of preferential flow. It seems that a population of connected preferential pathways is favourable both for resilience and stability of these soils during extreme events and to retain water resources for the ecosystem at the same time. We suggest that this principle of ?maximum energy dissipation? may on the long term help us to better understand why soil structures remain stable, threshold nature of preferential as well as offer a means to further reduce model structural uncertainty. Bloeschl, G. 2006. Idle thoughts on a unifying theory of catchment Hydrology. Geophysical Research Abstracts, Vol. 8, 10677, 2006 SRef-ID: 1607-7962/gra/EGU06-A-10677 European Geosciences Union 2006 Kleidon, A., and S. Schymanski (2008), Thermodynamics and optimality of the water budget on land: A review, Geophys. Res. Lett., 35, L20404, doi:10.1029/ 2008GL035393.

  3. A Stable Vanadium Redox-Flow Battery with High Energy Density for Large-scale Energy Storage

    SciTech Connect

    Li, Liyu; Kim, Soowhan; Wang, Wei; Vijayakumar, M.; Nie, Zimin; Chen, Baowei; Zhang, Jianlu; Xia, Guanguang; Hu, Jian Z.; Graff, Gordon L.; Liu, Jun; Yang, Zhenguo

    2011-05-01

    Low cost, high performance redox flow batteries are highly demanded for up to multi-megawatt levels of renewable and grid energy storage. Here, we report a new vanadium redox flow battery with a significant improvement over the current technologies. This new battery utilizes a sulfate-chloride mixed solution, which is capable of dissolving more than 2.5 M vanadium or about a 70% increase in the energy storage capacity over the current vanadium sulfate system. More importantly, the new electrolyte remains stable over a wide temperature range of -5 to 60oC, potentially eliminating the need of active heat management. Its high energy density, broad operational temperature window, and excellent electrochemical performance would lead to a significant reduction in the cost of energy storage, thus accelerating its market penetration.

  4. Modeling end-use quality in U. S. soft wheat germplasm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    End-use quality in soft wheat (Triticum aestivum L.) can be assessed by a wide array of measurements, generally categorized into grain, milling, and baking characteristics. Samples were obtained from four regional nurseries. Selected parameters included: test weight, kernel hardness, kernel size, ke...

  5. Chaper 20: Passing the Test on Wheat End-Use Quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Optimum results for wheat flour products depend on a specific array of functional properties. The factors that impact suitability for a specific end-use include kernel texture, starch properties, and gluten composition. Each of the attributes that contribute to product quality vary qualitatively or ...

  6. Ambipolar zinc-polyiodide electrolyte for a high-energy density aqueous redox flow battery

    NASA Astrophysics Data System (ADS)

    Li, Bin; Nie, Zimin; Vijayakumar, M.; Li, Guosheng; Liu, Jun; Sprenkle, Vincent; Wang, Wei

    2015-02-01

    Redox flow batteries are receiving wide attention for electrochemical energy storage due to their unique architecture and advantages, but progress has so far been limited by their low energy density (~25 Wh l-1). Here we report a high-energy density aqueous zinc-polyiodide flow battery. Using the highly soluble iodide/triiodide redox couple, a discharge energy density of 167 Wh l-1 is demonstrated with a near-neutral 5.0 M ZnI2 electrolyte. Nuclear magnetic resonance study and density functional theory-based simulation along with flow test data indicate that the addition of an alcohol (ethanol) induces ligand formation between oxygen on the hydroxyl group and the zinc ions, which expands the stable electrolyte temperature window to from -20 to 50 °C, while ameliorating the zinc dendrite. With the high-energy density and its benign nature free from strong acids and corrosive components, zinc-polyiodide flow battery is a promising candidate for various energy storage applications.

  7. PCB Food Web Dynamics Quantify Nutrient and Energy Flow in Aquatic Ecosystems.

    PubMed

    McLeod, Anne M; Paterson, Gordon; Drouillard, Ken G; Haffner, G Douglas

    2015-11-01

    Measuring in situ nutrient and energy flows in spatially and temporally complex aquatic ecosystems represents a major ecological challenge. Food web structure, energy and nutrient budgets are difficult to measure, and it is becoming more important to quantify both energy and nutrient flow to determine how food web processes and structure are being modified by multiple stressors. We propose that polychlorinated biphenyl (PCB) congeners represent an ideal tracer to quantify in situ energy and nutrient flow between trophic levels. Here, we demonstrate how an understanding of PCB congener bioaccumulation dynamics provides multiple direct measurements of energy and nutrient flow in aquatic food webs. To demonstrate this novel approach, we quantified nitrogen (N), phosphorus (P) and caloric turnover rates for Lake Huron lake trout, and reveal how these processes are regulated by both growth rate and fish life history. Although minimal nutrient recycling was observed in young growing fish, slow growing, older lake trout (>5 yr) recycled an average of 482 Tonnes·yr(-1) of N, 45 Tonnes·yr(-1) of P and assimilated 22 TJ yr(-1) of energy. Compared to total P loading rates of 590 Tonnes·yr(-1), the recycling of primarily bioavailable nutrients by fish plays an important role regulating the nutrient states of oligotrophic lakes.

  8. Ambipolar zinc-polyiodide electrolyte for a high-energy density aqueous redox flow battery

    PubMed Central

    Li, Bin; Nie, Zimin; Vijayakumar, M.; Li, Guosheng; Liu, Jun; Sprenkle, Vincent; Wang, Wei

    2015-01-01

    Redox flow batteries are receiving wide attention for electrochemical energy storage due to their unique architecture and advantages, but progress has so far been limited by their low energy density (~25 Wh l−1). Here we report a high-energy density aqueous zinc-polyiodide flow battery. Using the highly soluble iodide/triiodide redox couple, a discharge energy density of 167 Wh l−1 is demonstrated with a near-neutral 5.0 M ZnI2 electrolyte. Nuclear magnetic resonance study and density functional theory-based simulation along with flow test data indicate that the addition of an alcohol (ethanol) induces ligand formation between oxygen on the hydroxyl group and the zinc ions, which expands the stable electrolyte temperature window to from −20 to 50 °C, while ameliorating the zinc dendrite. With the high-energy density and its benign nature free from strong acids and corrosive components, zinc-polyiodide flow battery is a promising candidate for various energy storage applications. PMID:25709083

  9. Ambipolar zinc-polyiodide electrolyte for a high-energy density aqueous redox flow battery.

    PubMed

    Li, Bin; Nie, Zimin; Vijayakumar, M; Li, Guosheng; Liu, Jun; Sprenkle, Vincent; Wang, Wei

    2015-01-01

    Redox flow batteries are receiving wide attention for electrochemical energy storage due to their unique architecture and advantages, but progress has so far been limited by their low energy density (~25 Wh l(-1)). Here we report a high-energy density aqueous zinc-polyiodide flow battery. Using the highly soluble iodide/triiodide redox couple, a discharge energy density of 167 Wh l(-1) is demonstrated with a near-neutral 5.0 M ZnI2 electrolyte. Nuclear magnetic resonance study and density functional theory-based simulation along with flow test data indicate that the addition of an alcohol (ethanol) induces ligand formation between oxygen on the hydroxyl group and the zinc ions, which expands the stable electrolyte temperature window to from -20 to 50 °C, while ameliorating the zinc dendrite. With the high-energy density and its benign nature free from strong acids and corrosive components, zinc-polyiodide flow battery is a promising candidate for various energy storage applications. PMID:25709083

  10. Ambipolar zinc-polyiodide electrolyte for a high-energy density aqueous redox flow battery.

    PubMed

    Li, Bin; Nie, Zimin; Vijayakumar, M; Li, Guosheng; Liu, Jun; Sprenkle, Vincent; Wang, Wei

    2015-02-24

    Redox flow batteries are receiving wide attention for electrochemical energy storage due to their unique architecture and advantages, but progress has so far been limited by their low energy density (~25 Wh l(-1)). Here we report a high-energy density aqueous zinc-polyiodide flow battery. Using the highly soluble iodide/triiodide redox couple, a discharge energy density of 167 Wh l(-1) is demonstrated with a near-neutral 5.0 M ZnI2 electrolyte. Nuclear magnetic resonance study and density functional theory-based simulation along with flow test data indicate that the addition of an alcohol (ethanol) induces ligand formation between oxygen on the hydroxyl group and the zinc ions, which expands the stable electrolyte temperature window to from -20 to 50 °C, while ameliorating the zinc dendrite. With the high-energy density and its benign nature free from strong acids and corrosive components, zinc-polyiodide flow battery is a promising candidate for various energy storage applications.

  11. Rotational-translational energy transfer in rarefied nonequilibrium flows

    NASA Technical Reports Server (NTRS)

    Boyd, Iain D.

    1990-01-01

    A new model for simulating the transfer of energy between the translational and rotational modes is derived for a homogeneous gas of diatomic molecules. The model has been developed specifically for use in discrete particle simulation methods where molecular motion and intermolecular collisions are treated at the molecular level. A temperature dependence is introduced which has been predicted by theory and observed in experiment. The new model is applied to the relaxation of rotational temperature, and is found to produce significant differences in comparison with the model normally employed at both high and low temperatures. Calculations have also been performed for a Mach 7 normal shock wave.

  12. 7 CFR 782.11 - Extent to which commodities are subject to end-use certificate regulations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Extent to which commodities are subject to end-use... (Continued) FARM SERVICE AGENCY, DEPARTMENT OF AGRICULTURE SPECIAL PROGRAMS END-USE CERTIFICATE PROGRAM Implementation of the End-Use Certificate Program § 782.11 Extent to which commodities are subject to...

  13. Numerical simulation of material and energy flow in an e-beam melt furnace

    SciTech Connect

    Westerberg, K.W.; McClelland, M.A.; Finlayson, B.A.

    1993-12-01

    A numerical analysis is made of the material and energy flow in an electron-beam furnace. Energy from an electron beam vaporizes metal confined in a water-cooled crucible. At the beam impact site a. recirculating liquid metal pool is surrounded by a shell of its own solid. A Galerkin finite element method is modified to solve for the flow and temperature fields along with interface locations. The deforming mesh is parameterized using spines that pivot and stretch as the interfaces move. Results are given for an aluminum vaporizer in which parametric variations are made in the e-beam power and liquid viscosity. The calculations reveal the importance of the coupling between the free boundaries and the flow and energy fields.

  14. Influence of Dissipated Forming Energy on Flow Curves of Austenitic Stainless Steel

    NASA Astrophysics Data System (ADS)

    Steinheimer, Rainer; Engel, Bernd

    2011-08-01

    Finite element (FE) simulations are widely used to design sheet metal forming processes. Flow curves and forming limit curves of the semi-finished goods are required for these computations. Mostly flow curves are obtained by conversions of stress-strain caracteristics from uniaxial tensile tests. In these calculations, uniform strain and stress within the gauge length is postulated until reaching elongation without necking. This precondition is true only if specimens remain homogenous during the test procedure. Effects from dissipated mechanical energy and heat flow on the results of uniaxial tensile tests were examined with specimen made of austenitic stainless steels with practical experiments and FE simulations.

  15. Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems

    SciTech Connect

    Hong, Tainzhen; Liu, Xaiobing

    2009-11-01

    With the current movement toward net zero energy buildings, many technologies are promoted with emphasis on their superior energy efficiency. The variable refrigerant flow (VRF) and ground source heat pump (GSHP) systems are probably the most competitive technologies among these. However, there are few studies reporting the energy efficiency of VRF systems compared with GSHP systems. In this article, a preliminary comparison of energy efficiency between the air-source VRF and GSHP systems is presented. The computer simulation results show that GSHP system is more energy efficient than the air-source VRF system for conditioning a small office building in two selected US climates. In general, GSHP system is more energy efficient than the air-source VRV system, especially when the building has significant heating loads. For buildings with less heating loads, the GSHP system could still perform better than the air-source VRF system in terms of energy efficiency, but the resulting energy savings may be marginal.

  16. Energy Efficient Thermal Management for Natural Gas Engine Aftertreatment via Active Flow Control

    SciTech Connect

    David K. Irick; Ke Nguyen; Vitacheslav Naoumov; Doug Ferguson

    2005-04-01

    The project is focused on the development of an energy efficient aftertreatment system capable of reducing NOx and methane by 90% from lean-burn natural gas engines by applying active exhaust flow control. Compared to conventional passive flow-through reactors, the proposed scheme cuts supplemental energy by 50%-70%. The system consists of a Lean NOx Trap (LNT) system and an oxidation catalyst. Through alternating flow control, a major amount of engine exhaust flows through a large portion of the LNT system in the absorption mode, while a small amount of exhaust goes through a small portion of the LNT system in the regeneration or desulfurization mode. By periodically reversing the exhaust gas flow through the oxidation catalyst, a higher temperature profile is maintained in the catalyst bed resulting in greater efficiency of the oxidation catalyst at lower exhaust temperatures. The project involves conceptual design, theoretical analysis, computer simulation, prototype fabrication, and empirical studies. This report details the progress during the first twelve months of the project. The primary activities have been to develop the bench flow reactor system, develop the computer simulation and modeling of the reverse-flow oxidation catalyst, install the engine into the test cell, and begin design of the LNT system.

  17. ENERGY EFFICIENT THERMAL MANAGEMENT FOR NATURAL GAS ENGINE AFTERTREATMENT VIA ACTIVE FLOW CONTROL

    SciTech Connect

    David K. Irick; Ke Nguyen

    2004-04-01

    The project is focused on the development of an energy efficient aftertreatment system capable of reducing NOx and methane by 90% from lean-burn natural gas engines by applying active exhaust flow control. Compared to conventional passive flow-through reactors, the proposed scheme cuts supplemental energy by 50%-70%. The system consists of a Lean NOx Trap (LNT) system and an oxidation catalyst. Through alternating flow control, a major amount of engine exhaust flows through a large portion of the LNT system in the absorption mode, while a small amount of exhaust goes through a small portion of the LNT system in the regeneration or desulfurization mode. By periodically reversing the exhaust gas flow through the oxidation catalyst, a higher temperature profile is maintained in the catalyst bed resulting in greater efficiency of the oxidation catalyst at lower exhaust temperatures. The project involves conceptual design, theoretical analysis, computer simulation, prototype fabrication, and empirical studies. This report details the progress during the first twelve months of the project. The primary activities have been to develop the bench flow reactor system, develop the computer simulation and modeling of the reverse-flow oxidation catalyst, install the engine into the test cell, and begin design of the LNT system.

  18. ZaP-HD: High Energy Density Z-Pinch Plasmas using Sheared Flow Stabilization

    NASA Astrophysics Data System (ADS)

    Golingo, R. P.; Shumlak, U.; Nelson, B. A.; Claveau, E. L.; Doty, S. A.; Forbes, E. G.; Hughes, M. C.; Kim, B.; Ross, M. P.; Weed, J. R.

    2015-11-01

    The ZaP-HD flow Z-pinch project investigates scaling the flow Z-pinch to High Energy Density Plasma, HEDP, conditions by using sheared flow stabilization. ZaP used a single power supply to produce 100 cm long Z-pinches that were quiescent for many radial Alfven times and axial flow-through times. The flow Z-pinch concept provides an approach to achieve HED plasmas, which are dimensionally large and persist for extended durations. The ZaP-HD device replaces the single power supply from ZaP with two separate power supplies to independently control the plasma flow and current in the Z-pinch. Equilibrium is determined by diagnostic measurements of the density with interferometry and digital holography, the plasma flow and temperature with passive spectroscopy, the magnetic field with surface magnetic probes, and plasma emission with optical imaging. The diagnostics fully characterize the plasma from its initiation in the coaxial accelerator, through the pinch, and exhaust from the assembly region. The plasma evolution is modeled with high resolution codes: Mach2, WARPX, and NIMROD. Experimental results and scaling analyses are presented. This work is supported by grants from the U.S. Department of Energy and the U.S. National Nuclear Security Administration.

  19. Energy Efficient Thermal Management for Natural Gas Engine Aftertreatment via Active Flow Control

    SciTech Connect

    David K. Irick; Ke Nguyen; Vitacheslav Naoumov; Doug Ferguson

    2006-04-01

    The project is focused on the development of an energy efficient aftertreatment system capable of reducing NOx and methane by 90% from lean-burn natural gas engines by applying active exhaust flow control. Compared to conventional passive flow-through reactors, the proposed scheme cuts supplemental energy by 50%-70%. The system consists of a Lean NOx Trap (LNT) system and an oxidation catalyst. Through alternating flow control, a major amount of engine exhaust flows through a large portion of the LNT system in the absorption mode, while a small amount of exhaust goes through a small portion of the LNT system in the regeneration or desulfurization mode. By periodically reversing the exhaust gas flow through the oxidation catalyst, a higher temperature profile is maintained in the catalyst bed resulting in greater efficiency of the oxidation catalyst at lower exhaust temperatures. The project involves conceptual design, theoretical analysis, computer simulation, prototype fabrication, and empirical studies. This report details the progress during the first twelve months of the project. The primary activities have been to develop the bench flow reactor system, develop the computer simulation and modeling of the reverse-flow oxidation catalyst, install the engine into the test cell, and begin design of the LNT system.

  20. Rossby wave energy dispersion from tropical cyclone in zonal basic flows

    NASA Astrophysics Data System (ADS)

    Shi, Wenli; Fei, Jianfang; Huang, Xiaogang; Liu, Yudi; Ma, Zhanhong; Yang, Lu

    2016-04-01

    This study investigates tropical cyclone energy dispersion under horizontally sheared flows using a nonlinear barotropic model. In addition to common patterns, unusual features of Rossby wave trains are also found in flows with constant vorticity and vorticity gradients. In terms of the direction of the energy dispersion, the wave train can rotate clockwise and elongate southwestward under anticyclonic circulation (ASH), which contributes to the reenhancement of the tropical cyclone (TC). The wave train even splits into two obvious wavelike trains in flows with a southward vorticity gradient (WSH). Energy dispersed from TCs varies over time, and variations in the intensity of the wave train components typically occur in two stages. Wave-activity flux diagnosis and ray tracing calculations are extended to the frame that moves along with the TC to reveal the concrete progress of wave propagation. The direction of the wave-activity flux is primarily determined by the combination of the basic flow and the TC velocity. Along the flux, the distribution of pseudomomentum effectively illustrates the development of wave trains, particularly the rotation and split of wave propagation. Ray tracing involves the quantitative tracing of wave features along rays, which effectively coincide with the wave train regimes. Flows of a constant shear (parabolic meridional variation) produce linear (nonlinear) wave number variations. For the split wave trains, the real and complex wave number waves move along divergent trajectories and are responsible for different energy dispersion ducts.

  1. Experiences with a large load research project in the Pacific Northwest: ELCAP (End-Use Load and Consumer Assessment Program)

    SciTech Connect

    Gillman, R.A.; Sandusky, W.F.; Patton, J.E.; Hauser, S.G.

    1989-05-01

    The Bonneville Power Administration (Bonneville) began the End-Use Load and Consumer Assessment Program (ELCAP) in August, 1983, to support demand side planning, forecasting, and demand side program development and delivery. This project, conducted for Bonneville by the Pacific Northwest Laboratory (PNL), which is operated for the Department of Energy by the Battelle Memorial Institute, involves the collection and analysis of hourly end-use electricity usage data together with detailed characteristics from approximately 400 residences and 100 commercial buildings in the Pacific Northwest. The purpose of this paper is to relate our experiences with the ELCAP from its early days to its current status. This paper will explore Bonneville's and PNL's experiences ranging from project formulation to technology development to current management issues. We will specifically cover knowledge gained from the development of data loggers, loggers installation, measurement protocols, and data quality assurance. Additionally, the more global issues associated with managing the ELCAP and maintaining agency support in a time of cost-consciousness will be discussed. These issues include the areas of budgets, perceptions, producing useful results, and data availability. 3 refs.

  2. Energy Efficient Engine Low Pressure Subsystem Flow Analysis

    NASA Technical Reports Server (NTRS)

    Hall, Edward J.; Lynn, Sean R.; Heidegger, Nathan J.; Delaney, Robert A.

    1998-01-01

    The objective of this project is to provide the capability to analyze the aerodynamic performance of the complete low pressure subsystem (LPS) of the Energy Efficient Engine (EEE). The analyses were performed using three-dimensional Navier-Stokes numerical models employing advanced clustered processor computing platforms. The analysis evaluates the impact of steady aerodynamic interaction effects between the components of the LPS at design and off-design operating conditions. Mechanical coupling is provided by adjusting the rotational speed of common shaft-mounted components until a power balance is achieved. The Navier-Stokes modeling of the complete low pressure subsystem provides critical knowledge of component aero/mechanical interactions that previously were unknown to the designer until after hardware testing.

  3. Influence of NO-containing gas flow on various parameters of energy metabolism in erythrocytes.

    PubMed

    Martusevich, A K; Solov'yova, A G; Peretyagin, S P; Karelin, V I; Selemir, V D

    2014-11-01

    We studied the influence of NO-containing gas phase on some parameters of energy metabolism in human erythrocytes. Whole blood samples were aerated with gas flows from the Plazon instrument (NO concentrations 800 and 80 ppm) and from the experimental generator (75 ppm). Activity of lactate dehydrogenase in direct and reverse reactions, lactate level, and a number of derived coefficients were estimated. Treatment of blood with 800 ppm NO inhibited erythrocyte energy metabolism, and its 10-fold dilution attenuated the effect. The use of ROS-free gas flow containing 75 ppm of NO promoted optimization of the process under investigation.

  4. Influence of NO-containing gas flow on various parameters of energy metabolism in erythrocytes.

    PubMed

    Martusevich, A K; Solov'yova, A G; Peretyagin, S P; Karelin, V I; Selemir, V D

    2014-11-01

    We studied the influence of NO-containing gas phase on some parameters of energy metabolism in human erythrocytes. Whole blood samples were aerated with gas flows from the Plazon instrument (NO concentrations 800 and 80 ppm) and from the experimental generator (75 ppm). Activity of lactate dehydrogenase in direct and reverse reactions, lactate level, and a number of derived coefficients were estimated. Treatment of blood with 800 ppm NO inhibited erythrocyte energy metabolism, and its 10-fold dilution attenuated the effect. The use of ROS-free gas flow containing 75 ppm of NO promoted optimization of the process under investigation. PMID:25403392

  5. Momentum-energy transport from turbulence driven by parallel flow shear

    SciTech Connect

    Dong, J.Q.; Horton, W.; Bengtson, R.D.; Li, G.X.

    1994-04-01

    The low frequency E {times} B turbulence driven by the shear in the mass flow velocity parallel to the magnetic field is studied using the fluid theory in a slab configuration with magnetic shear. Ion temperature gradient effects are taken into account. The eigenfunctions of the linear instability are asymmetric about the mode rational surfaces. Quasilinear Reynolds stress induced by such asymmetric fluctuations produces momentum and energy transport across the magnetic field. Analytic formulas for the parallel and perpendicular Reynolds stress, viscosity and energy transport coefficients are given. Experimental observations of the parallel and poloidal plasma flows on TEXT-U are presented and compared with the theoretical models.

  6. Ambipolar zinc-polyiodide electrolyte for a high-energy density aqueous redox flow battery

    DOE PAGES

    Li, Bin; Nie, Zimin; Vijayakumar, M.; Li, Guosheng; Liu, Jun; Sprenkle, Vincent L.; Wang, Wei

    2015-02-24

    Large-scale energy storage systems are crucial for substantial deployment of renewable energy sources. Energy storage systems with high energy density, high safety, and low cost and environmental friendliness are desired. To overcome the major limitations of the current aqueous redox flow battery systems, namely lower energy density (~25 Wh L-1) and presence of strong acids and/or other hazardous, a high energy density aqueous zinc/polyiodide flow battery (ZIB) is designed with near neutral ZnI2 solutions as catholytes. The energy density of ZIB could reach 322 Wh L-1 at the solubility limit of ZnI2 in water (~7 M). We demonstrate charge andmore » discharge energy densities of 245.9 Wh/L and 166.7 Wh L-1 with ZnI2 electrolyte at 5.0 M, respectively. The addition of ethanol (EtOH) in ZnI2 electrolyte can effectively mitigate the growth of zinc dendrite at the anode and improve the stability of catholytes with wider temperature window (-20 to 50°C), which enable ZIB system to be a promising alternative as a high-energy and high- safety stationary energy storage system.« less

  7. Ambipolar zinc-polyiodide electrolyte for a high-energy density aqueous redox flow battery

    SciTech Connect

    Li, Bin; Nie, Zimin; Vijayakumar, M.; Li, Guosheng; Liu, Jun; Sprenkle, Vincent L.; Wang, Wei

    2015-02-24

    Large-scale energy storage systems are crucial for substantial deployment of renewable energy sources. Energy storage systems with high energy density, high safety, and low cost and environmental friendliness are desired. To overcome the major limitations of the current aqueous redox flow battery systems, namely lower energy density (~25 Wh L-1) and presence of strong acids and/or other hazardous, a high energy density aqueous zinc/polyiodide flow battery (ZIB) is designed with near neutral ZnI2 solutions as catholytes. The energy density of ZIB could reach 322 Wh L-1 at the solubility limit of ZnI2 in water (~7 M). We demonstrate charge and discharge energy densities of 245.9 Wh/L and 166.7 Wh L-1 with ZnI2 electrolyte at 5.0 M, respectively. The addition of ethanol (EtOH) in ZnI2 electrolyte can effectively mitigate the growth of zinc dendrite at the anode and improve the stability of catholytes with wider temperature window (-20 to 50°C), which enable ZIB system to be a promising alternative as a high-energy and high- safety stationary energy storage system.

  8. Boltzmann rovibrational collisional coarse-grained model for internal energy excitation and dissociation in hypersonic flows.

    PubMed

    Munafò, A; Panesi, M; Magin, T E

    2014-02-01

    A Boltzmann rovibrational collisional coarse-grained model is proposed to reduce a detailed kinetic mechanism database developed at NASA Ames Research Center for internal energy transfer and dissociation in N(2)-N interactions. The coarse-grained model is constructed by lumping the rovibrational energy levels of the N(2) molecule into energy bins. The population of the levels within each bin is assumed to follow a Boltzmann distribution at the local translational temperature. Excitation and dissociation rate coefficients for the energy bins are obtained by averaging the elementary rate coefficients. The energy bins are treated as separate species, thus allowing for non-Boltzmann distributions of their populations. The proposed coarse-grained model is applied to the study of nonequilibrium flows behind normal shock waves and within converging-diverging nozzles. In both cases, the flow is assumed inviscid and steady. Computational results are compared with those obtained by direct solution of the master equation for the rovibrational collisional model and a more conventional multitemperature model. It is found that the proposed coarse-grained model is able to accurately resolve the nonequilibrium dynamics of internal energy excitation and dissociation-recombination processes with only 20 energy bins. Furthermore, the proposed coarse-grained model provides a superior description of the nonequilibrium phenomena occurring in shock heated and nozzle flows when compared with the conventional multitemperature models.

  9. Joint torque and mechanical energy flow in the support legs of skilled race walkers.

    PubMed

    Hoga, Koji; Ae, Michiyoshi; Enomoto, Yasushi; Yokozawa, Toshiharu; Fujii, Norihisa

    2006-07-01

    This study analyzed the joint torque and the mechanical energy flow in the support legs of skilled male race walkers. Twelve race walkers were videotaped using a high-speed camera at a frame rate of 250 Hz set perpendicular to the sagittal plane of motion; their ground reaction forces were measured with two force platforms. A two-dimensional, 14-segment, linked model was used to calculate the kinetics of the support leg joints. In the initial part of the support phase, the mechanical energy flowed into the thigh and shank by the torque of the large hip extensors and knee flexors. In the middle part, the mechanical energy generated by the torque of the large plantar flexors flowed to the foot and from the foot to the shank by the ankle joint force. The mechanical energy flow by the forward joint force of the support hip was significantly related to the walking speed in the final part of the support phase. Our findings suggest that race walkers in the final part of the support phase should exert the torque of the knee extensors and hip flexors to transfer the mechanical energy more effectively to the support thigh and shank.

  10. Pathways to low-cost electrochemical energy storage: a comparison of aqueous and nonaqueous flow batteries

    DOE PAGES

    Darling, Robert M.; Gallagher, Kevin G.; Kowalski, Jeffrey A.; Ha, Seungbum; Brushett, Fikile R.

    2014-11-01

    Energy storage is increasingly seen as a valuable asset for electricity grids composed of high fractions of intermittent sources, such as wind power or, in developing economies, unreliable generation and transmission services. However, the potential of batteries to meet the stringent cost and durability requirements for grid applications is largely unquantified. We investigate electrochemical systems capable of economically storing energy for hours and present an analysis of the relationships among technological performance characteristics, component cost factors, and system price for established and conceptual aqueous and nonaqueous batteries. We identified potential advantages of nonaqueous flow batteries over those based on aqueousmore » electrolytes; however, new challenging constraints burden the nonaqueous approach, including the solubility of the active material in the electrolyte. Requirements in harmony with economically effective energy storage are derived for aqueous and nonaqueous systems. The attributes of flow batteries are compared to those of aqueous and nonaqueous enclosed and hybrid (semi-flow) batteries. Flow batteries are a promising technology for reaching these challenging energy storage targets owing to their independent power and energy scaling, reliance on facile and reversible reactants, and potentially simpler manufacture as compared to established enclosed batteries such as lead–acid or lithium-ion.« less

  11. Pathways to low-cost electrochemical energy storage: a comparison of aqueous and nonaqueous flow batteries

    SciTech Connect

    Darling, Robert M.; Gallagher, Kevin G.; Kowalski, Jeffrey A.; Ha, Seungbum; Brushett, Fikile R.

    2014-11-01

    Energy storage is increasingly seen as a valuable asset for electricity grids composed of high fractions of intermittent sources, such as wind power or, in developing economies, unreliable generation and transmission services. However, the potential of batteries to meet the stringent cost and durability requirements for grid applications is largely unquantified. We investigate electrochemical systems capable of economically storing energy for hours and present an analysis of the relationships among technological performance characteristics, component cost factors, and system price for established and conceptual aqueous and nonaqueous batteries. We identified potential advantages of nonaqueous flow batteries over those based on aqueous electrolytes; however, new challenging constraints burden the nonaqueous approach, including the solubility of the active material in the electrolyte. Requirements in harmony with economically effective energy storage are derived for aqueous and nonaqueous systems. The attributes of flow batteries are compared to those of aqueous and nonaqueous enclosed and hybrid (semi-flow) batteries. Flow batteries are a promising technology for reaching these challenging energy storage targets owing to their independent power and energy scaling, reliance on facile and reversible reactants, and potentially simpler manufacture as compared to established enclosed batteries such as lead–acid or lithium-ion.

  12. Impact of Groundwater Flow and Energy Load on Multiple Borehole Heat Exchangers.

    PubMed

    Dehkordi, S Emad; Schincariol, Robert A; Olofsson, Bo

    2015-01-01

    The effect of array configuration, that is, number, layout, and spacing, on the performance of multiple borehole heat exchangers (BHEs) is generally known under the assumption of fully conductive transport. The effect of groundwater flow on BHE performance is also well established, but most commonly for single BHEs. In multiple-BHE systems the effect of groundwater advection can be more complicated due to the induced thermal interference between the boreholes. To ascertain the influence of groundwater flow and borehole arrangement, this study investigates single- and multi-BHE systems of various configurations. Moreover, the influence of energy load balance is also examined. The results from corresponding cases with and without groundwater flow as well as balanced and unbalanced energy loads are cross-compared. The groundwater flux value, 10(-7) m/s, is chosen based on the findings of previous studies on groundwater flow interaction with BHEs and thermal response tests. It is observed that multi-BHE systems with balanced loads are less sensitive to array configuration attributes and groundwater flow, in the long-term. Conversely, multi-BHE systems with unbalanced loads are influenced by borehole array configuration as well as groundwater flow; these effects become more pronounced with time, unlike when the load is balanced. Groundwater flow has more influence on stabilizing loop temperatures, compared to array characteristics. Although borehole thermal energy storage (BTES) systems have a balanced energy load function, preliminary investigation on their efficiency shows a negative impact by groundwater which is due to their dependency on high temperature gradients between the boreholes and surroundings.

  13. Impact of Groundwater Flow and Energy Load on Multiple Borehole Heat Exchangers.

    PubMed

    Dehkordi, S Emad; Schincariol, Robert A; Olofsson, Bo

    2015-01-01

    The effect of array configuration, that is, number, layout, and spacing, on the performance of multiple borehole heat exchangers (BHEs) is generally known under the assumption of fully conductive transport. The effect of groundwater flow on BHE performance is also well established, but most commonly for single BHEs. In multiple-BHE systems the effect of groundwater advection can be more complicated due to the induced thermal interference between the boreholes. To ascertain the influence of groundwater flow and borehole arrangement, this study investigates single- and multi-BHE systems of various configurations. Moreover, the influence of energy load balance is also examined. The results from corresponding cases with and without groundwater flow as well as balanced and unbalanced energy loads are cross-compared. The groundwater flux value, 10(-7) m/s, is chosen based on the findings of previous studies on groundwater flow interaction with BHEs and thermal response tests. It is observed that multi-BHE systems with balanced loads are less sensitive to array configuration attributes and groundwater flow, in the long-term. Conversely, multi-BHE systems with unbalanced loads are influenced by borehole array configuration as well as groundwater flow; these effects become more pronounced with time, unlike when the load is balanced. Groundwater flow has more influence on stabilizing loop temperatures, compared to array characteristics. Although borehole thermal energy storage (BTES) systems have a balanced energy load function, preliminary investigation on their efficiency shows a negative impact by groundwater which is due to their dependency on high temperature gradients between the boreholes and surroundings. PMID:25227154

  14. Nuclear energy information flow from DOE to the public

    SciTech Connect

    Simmons, J.L.; Rankin, W.L.; Nealey, S.M.

    1980-06-01

    The objective of this research was to study the DOE's program for educating the public about nuclear power and nuclear waste management. DOE's organizational structuree and the procedures used within this structure to disseminate information were studied and readability tests on nuclear information distributed by DOE were conducted. Initial information was obtained through interviews with 29 local, state, and federal DOE representatives. This was supplemented with additional information as it was released by the DOE. The primary goals of the DOE's information program are to encourage two-way communication between the DOE and the public and to encourage public participation in policy-making decisions. Most of this communication, however, is presented orally. Relative to other energy technologies and conservation, very few nuclear brochures are currently being distributed by the DOE. This is especially true with regard to information about nuclear waste. A recent public survey found that a majority of the public wants to learn more about nuclear power and that, with regard to the nuclear fuel cycle, the public wants most to learn about nuclear waste management. Thus, the DOE appears to be missing an eager audience.

  15. Energy Flow in the Polar F-region Ionosphere-Thermosphere System through an Indirect Momentum-Energy Coupling Mechanism

    NASA Astrophysics Data System (ADS)

    Hsu, V.; Thayer, J. P.; Wang, W.; Burns, A. G.

    2015-12-01

    Thermospheric neutral properties, such as wind, temperature, and neutral mass density, are driven by momentum and energy sources. Much work has focused on the response of the thermosphere when driven by energy sources from the magnetosphere, resulting in direct heating of the neutral gas. This leads to a dynamical response of the thermosphere described as a direct wind circulation. However, sources that change the momentum transfer to the neutral gas can also lead to thermal changes through a dynamical response that would be characterized as an indirect wind circulation. The ionosphere-thermosphere (I/T) system is tightly coupled by momentum and energy. The path for a direct energy source is to change the energy and then the momentum, while the route for an indirect energy source is to change the momentum and then the energy. For the indirect energy source, changes in the ion drag force cause a divergence in the neutral wind field, which results in thermal changes due to adiabatic heating or cooling via vertical winds. All of the important forces and processes exist for describing both the direct and indirect energy sources, but it is the time evolution of the processes that will define how the thermosphere responds. In this work, we present an indirect energy mechanism that can alter the thermospheric neutral mass density and temperature in the polar F-region. Similar to energy partitioning within the high-latitude I/T from an external energy source, energy can be transferred from kinetic to internal energy from a momentum source. We use the NCAR TIEGCM to analyze quantitatively how energy flows through the polar I/T system due to an internal momentum modification. These results illustrate how changes in the ion drag force can affect the thermal energy of the polar F-region I/T system, and create neutral mass density and temperature anomalies.

  16. Transient unidirectional energy flow and diode-like phenomenon induced by non-Markovian environments

    PubMed Central

    Jing, Jun; Segal, Dvira; Li, Baowen; Wu, Lian-Ao

    2015-01-01

    Relying on an exact time evolution scheme, we identify a novel transient energy transfer phenomenon in an exactly-solvable quantum microscopic model consisting of a three-level system coupled to two non-Markovian zero-temperature bosonic baths through two separable quantum channels. The dynamics of this model can be solved exactly using the quantum-state-diffusion equation formalism, demonstrating finite intervals of unidirectional energy flow across the system, typically, from the non-Markovian environment towards the more Markovian bath. Furthermore, when introducing a spatial asymmetry into the system, an analogue of the rectification effect is realized. In the long time limit, the dynamics arrives at a stationary state and the effects recede. Understanding temporal characteristics of directional energy flow will aid in designing microscopic energy transfer devices. PMID:26478230

  17. Design and optimization of a large flow rate booster pump in SWRO energy recovery system

    NASA Astrophysics Data System (ADS)

    Lai, Z. N.; Wu, P.; Wu, D. Z.; Wang, L. Q.

    2013-12-01

    Seawater reverse osmosis (SWRO) is a high energy-consumption industry, so energy efficiency is an important issue. Energy recovery systems, which contain a pressure exchanger and a booster pump, are widely used in SWRO plants. As a key part of energy recovery system, the difficulty of designing booster pumps lies in high inlet pressure, high medium causticity and large flow rate. High inlet pressure adds difficulties to seal design, and large flow rate and high efficiency requirement bring high demand for hydraulic design. In this paper, a 625 m3/h booster pump is designed and optimized according to the CFD (Computational Fluid Dynamics) simulation results. The impeller and volute is well designed, a new type of high pressure mechanical seal is applied and axial force is well balanced. After optimization based on blade redesign, the efficiency of the pump was improved. The best efficiency reaches more than 85% at design point according to the CFD simulation result.

  18. Transient unidirectional energy flow and diode-like phenomenon induced by non-Markovian environments.

    PubMed

    Jing, Jun; Segal, Dvira; Li, Baowen; Wu, Lian-Ao

    2015-10-19

    Relying on an exact time evolution scheme, we identify a novel transient energy transfer phenomenon in an exactly-solvable quantum microscopic model consisting of a three-level system coupled to two non-Markovian zero-temperature bosonic baths through two separable quantum channels. The dynamics of this model can be solved exactly using the quantum-state-diffusion equation formalism, demonstrating finite intervals of unidirectional energy flow across the system, typically, from the non-Markovian environment towards the more Markovian bath. Furthermore, when introducing a spatial asymmetry into the system, an analogue of the rectification effect is realized. In the long time limit, the dynamics arrives at a stationary state and the effects recede. Understanding temporal characteristics of directional energy flow will aid in designing microscopic energy transfer devices.

  19. Impact of Energy Slope Averaging Methods on Numerical Solution of 1D Steady Gradually Varied Flow

    NASA Astrophysics Data System (ADS)

    Artichowicz, Wojciech; Prybytak, Dzmitry

    2015-12-01

    In this paper, energy slope averaging in the one-dimensional steady gradually varied flow model is considered. For this purpose, different methods of averaging the energy slope between cross-sections are used. The most popular are arithmetic, geometric, harmonic and hydraulic means. However, from the formal viewpoint, the application of different averaging formulas results in different numerical integration formulas. This study examines the basic properties of numerical methods resulting from different types of averaging.

  20. Material and Energy Flows Associated with Select Metals in GREET 2. Molybdenum, Platinum, Zinc, Nickel, Silicon

    SciTech Connect

    Benavides, Pahola T.; Dai, Qiang; Sullivan, John L.; Kelly, Jarod C.; Dunn, Jennifer B.

    2015-09-01

    In this work, we analyzed the material and energy consumption from mining to production of molybdenum, platinum, zinc, and nickel. We also analyzed the production of solar- and semiconductor-grade silicon. We described new additions to and expansions of the data in GREET 2. In some cases, we used operating permits and sustainability reports to estimate the material and energy flows for molybdenum, platinum, and nickel, while for zinc and silicon we relied on information provided in the literature.

  1. Revealing β-relaxation mechanism based on energy distribution of flow units in metallic glass

    NASA Astrophysics Data System (ADS)

    Lu, Z.; Shang, B. S.; Sun, Y. T.; Zhu, Z. G.; Guan, P. F.; Wang, W. H.; Bai, H. Y.

    2016-04-01

    The β-relaxation, which is the source of the dynamics in glass state and has practical significance to relaxation and mechanical properties of glasses, has been an open question for decades. Here, we propose a flow unit perspective to explain the structural origin and evolution of β-relaxation based on experimentally obtained energy distribution of flow units using stress relaxation method under isothermal and linear heating modes. Through the molecular dynamics simulations, we creatively design various artificial metallic glass systems and build a direct relation between β-relaxation behavior and features of flow units. Our results demonstrate that the β-relaxation in metallic glasses originates from flow units and is modulated by the energy distribution of flow units, and the density and distribution of flow units can effectively regulate the β-relaxation behavior. The results provide a better understanding of the structural origin of β-relaxation and also afford a method for designing metallic glasses with obvious β-relaxation and better mechanical properties.

  2. Shear flow energy redistribution stipulated by the internal-gravity wavy structures in the dissipative ionosphere

    NASA Astrophysics Data System (ADS)

    Aburjania, G. D.; Chargazia, K. Z.; Kharshiladze, O. A.

    2013-07-01

    The linear mechanism of generation, intensification and further nonlinear dynamics of internal gravity waves (IGW) in stably stratified dissipative ionosphere with non-uniform zonal wind (shear flow) is studied. In case of the shear flows the operators of linear problem are non-selfadjoint, and the corresponding Eigen functions - nonorthogonal. Thus, canonical - modal approach is of less use studying such motions. Non-modal mathematical analysis becomes more adequate for such problems. On the basis of non-modal approach, the equations of dynamics and the energy transfer of IGW disturbances in the ionosphere with a shear flow is obtained. Exact analytical solutions of the linear as well as the nonlinear dynamic equations of the problem are built. The increment of shear instability of IGW is defined. It is revealed that the transient amplification of IGW disturbances due time does not flow exponentially, but in algebraic - power law manner. The effectiveness of the linear amplification mechanism of IGW at interaction with non-uniform zonal wind is analyzed. It is shown that at initial linear stage of evolution IGW effectively temporarily draws energy from the shear flow significantly increasing (by an order of magnitude) own amplitude and energy. With amplitude growth the nonlinear mechanism turns on and the process ends with self-organization of nonlinear solitary, strongly localized IGW vortex structures (the monopole vortex, the transverse vortex chain or the longitudinal vortex street). Accumulation of these vortices in the ionospheric medium can create the strongly turbulent state.

  3. Chemical Energy Release in Several Recently Discovered Detonation and Deflagration Flows

    NASA Astrophysics Data System (ADS)

    Tarver, Craig M.

    2010-10-01

    Several recent experiments on complex detonation and deflagration flows are analyzed in terms of the chemical energy release required to sustain these flows. The observed double cellular structures in detonating gaseous nitromethane-oxygen and NO2-fuel (H2, CH4, and C2H6) mixtures are explained by the amplification of two distinct pressure wave frequencies by two exothermic reactions, the faster reaction forming vibrationally excited NO* and the slower reaction forming highly vibrationally excited N2**. The establishment of a Chapman-Jouguet (C-J) deflagration behind a weak shock wave, the C-J detonation established after a head-on collision with a shock front, and the C-J detonation conditions established in reactive supersonic flows are quantitatively calculated using the chemical energy release of a H2 + Cl2 mixture. For these three reactive flows, these calculations illustrate that different fractions of the exothermic chemical energy are used to sustain steady-state propagation. C-J detonation calculations on the various initial states using the CHEETAH chemical equilibrium code are shown to be in good agreement with experimental detonation velocity measurements for the head-on collision and supersonic flow detonations.

  4. A Crosswalk of Mineral Commodity End Uses and North American Industry Classification System (NAICS) codes

    USGS Publications Warehouse

    Barry, James J.; Matos, Grecia R.; Menzie, W. David

    2015-09-14

    The links between the end uses of mineral commodities and the NAICS codes provide an instrument for analyzing the use of mineral commodities in the economy. The crosswalk is also a guide, highlighting those industrial sectors in the economy that rely heavily on mineral commodities. The distribution of mineral commodities across the economy is dynamic and does differ from year to year. This report reflects a snapshot of the state of the economy and mineral commodities in 2010.

  5. A Crosswalk of Mineral Commodity End Uses and North American Industry Classification System (NAICS) codes

    USGS Publications Warehouse

    Barry, James J.; Matos, Grecia R.; Menzie, W. David

    2015-01-01

    The links between the end uses of mineral commodities and the NAICS codes provide an instrument for analyzing the use of mineral commodities in the economy. The crosswalk is also a guide, highlighting those industrial sectors in the economy that rely heavily on mineral commodities. The distribution of mineral commodities across the economy is dynamic and does differ from year to year. This report reflects a snapshot of the state of the economy and mineral commodities in 2010.

  6. Aqueous Lithium-Iodine Solar Flow Battery for the Simultaneous Conversion and Storage of Solar Energy.

    PubMed

    Yu, Mingzhe; McCulloch, William D; Beauchamp, Damian R; Huang, Zhongjie; Ren, Xiaodi; Wu, Yiying

    2015-07-01

    Integrating both photoelectric-conversion and energy-storage functions into one device allows for the more efficient solar energy usage. Here we demonstrate the concept of an aqueous lithium-iodine (Li-I) solar flow battery (SFB) by incorporation of a built-in dye-sensitized TiO2 photoelectrode in a Li-I redox flow battery via linkage of an I3(-)/I(-) based catholyte, for the simultaneous conversion and storage of solar energy. During the photoassisted charging process, I(-) ions are photoelectrochemically oxidized to I3(-), harvesting solar energy and storing it as chemical energy. The Li-I SFB can be charged at a voltage of 2.90 V under 1 sun AM 1.5 illumination, which is lower than its discharging voltage of 3.30 V. The charging voltage reduction translates to energy savings of close to 20% compared to conventional Li-I batteries. This concept also serves as a guiding design that can be extended to other metal-redox flow battery systems. PMID:26102317

  7. Aqueous Lithium-Iodine Solar Flow Battery for the Simultaneous Conversion and Storage of Solar Energy.

    PubMed

    Yu, Mingzhe; McCulloch, William D; Beauchamp, Damian R; Huang, Zhongjie; Ren, Xiaodi; Wu, Yiying

    2015-07-01

    Integrating both photoelectric-conversion and energy-storage functions into one device allows for the more efficient solar energy usage. Here we demonstrate the concept of an aqueous lithium-iodine (Li-I) solar flow battery (SFB) by incorporation of a built-in dye-sensitized TiO2 photoelectrode in a Li-I redox flow battery via linkage of an I3(-)/I(-) based catholyte, for the simultaneous conversion and storage of solar energy. During the photoassisted charging process, I(-) ions are photoelectrochemically oxidized to I3(-), harvesting solar energy and storing it as chemical energy. The Li-I SFB can be charged at a voltage of 2.90 V under 1 sun AM 1.5 illumination, which is lower than its discharging voltage of 3.30 V. The charging voltage reduction translates to energy savings of close to 20% compared to conventional Li-I batteries. This concept also serves as a guiding design that can be extended to other metal-redox flow battery systems.

  8. A comprehensive framework for the assessment of new end uses in recycled water schemes.

    PubMed

    Chen, Zhuo; Ngo, Huu Hao; Guo, Wenshan; Lim, Richard; Wang, Xiaochang C; O'Halloran, Kelly; Listowski, Andrzej; Corby, Nigel; Miechel, Clayton

    2014-02-01

    Nowadays, recycled water has provided sufficient flexibility to satisfy short-term freshwater needs and increase the reliability of long-term water supplies in many water scarce areas, which becomes an essential component of integrated water resources management. However, the current applications of recycled water are still quite limited that are mainly associated with non-potable purposes such as irrigation, industrial uses, toilet flushing and car washing. There is a large potential to exploit and develop new end uses of recycled water in both urban and rural areas. This can greatly contribute to freshwater savings, wastewater reduction and water sustainability. Consequently, the paper identified the potentials for the development of three recycled water new end uses, household laundry, livestock feeding and servicing, and swimming pool, in future water use market. To validate the strengths of these new applications, a conceptual decision analytic framework was proposed. This can be able to facilitate the optional management strategy selection process and thereafter provide guidance on the future end use studies within a larger context of the community, processes, and models in decision-making. Moreover, as complex evaluation criteria were selected and taken into account to narrow down the multiple management alternatives, the methodology can successfully add transparency, objectivity and comprehensiveness to the assessment. Meanwhile, the proposed approach could also allow flexibility to adapt to particular circumstances of each case under study.

  9. Deterministic and stochastic algorithms for resolving the flow fields in ducts and networks using energy minimization

    NASA Astrophysics Data System (ADS)

    Sochi, Taha

    2016-09-01

    Several deterministic and stochastic multi-variable global optimization algorithms (Conjugate Gradient, Nelder-Mead, Quasi-Newton and global) are investigated in conjunction with energy minimization principle to resolve the pressure and volumetric flow rate fields in single ducts and networks of interconnected ducts. The algorithms are tested with seven types of fluid: Newtonian, power law, Bingham, Herschel-Bulkley, Ellis, Ree-Eyring and Casson. The results obtained from all those algorithms for all these types of fluid agree very well with the analytically derived solutions as obtained from the traditional methods which are based on the conservation principles and fluid constitutive relations. The results confirm and generalize the findings of our previous investigations that the energy minimization principle is at the heart of the flow dynamics systems. The investigation also enriches the methods of computational fluid dynamics for solving the flow fields in tubes and networks for various types of Newtonian and non-Newtonian fluids.

  10. Catchment organisation, free energy dynamics and network control on critical zone water flows

    NASA Astrophysics Data System (ADS)

    Zehe, E.; Ehret, U.; Kleidon, A.; Jackisch, C.; Scherer, U.; Blume, T.

    2012-04-01

    as that these flow structures organize and dominate flows of water, dissolved matter and sediments during rainfall driven conditions at various scales: - Surface connected vertical flow structures of anecic worm burrows or soil cracks organize and dominated vertical flows at the plot scale - this is usually referred to as preferential flow; - Rill networks at the soil surface organise and dominate hillslope scale overland flow response and sediment yields; - Subsurface pipe networks at the bedrock interface organize and dominate hillslope scale lateral subsurface water and tracer flows; - The river net organizes and dominates flows of water, dissolved matter and sediments to the catchment outlet and finally across continental gradients to the sea. Fundamental progress with respect to the parameterization of hydrological models, subscale flow networks and to understand the adaptation of hydro-geo ecosystems to change could be achieved by discovering principles that govern the organization of catchments flow networks in particular at least during steady state conditions. This insight has inspired various scientists to suggest principles for organization of ecosystems, landscapes and flow networks; as Bejans constructural law, Minimum Energy Expenditure , Maximum Entropy Production. In line with these studies we suggest that a thermodynamic/energetic treatment of the catchment is might be a key for understanding the underlying principles that govern organisation of flow and transport. Our approach is to employ a) physically based hydrological model that address at least all the relevant hydrological processes in the critical zone in a coupled way, behavioural representations of the observed organisation of flow structures and textural elements, that are consistent with observations in two well investigated research catchments and have been tested against distributed observations of soil moisture and catchment scale discharge; to simulate the full concert of hydrological

  11. Subsonic and Supersonic shear flows in laser driven high-energy-density plasmas

    NASA Astrophysics Data System (ADS)

    Harding, E. C.; Drake, R. P.; Gillespie, R. S.; Grosskopf, M. J.; Kuranz, C. C.; Visco, A.; Ditmar, J. R.; Aglitskiy, Y.; Weaver, J. L.; Velikovich, A. L.; Hurricane, O. A.; Hansen, J. F.; Remington, B. A.; Robey, H. F.; Bono, M. J.; Plewa, T.

    2009-05-01

    Shear flows arise in many high-energy-density (HED) and astrophysical systems, yet few laboratory experiments have been carried out to study their evolution in these extreme environments. Fundamentally, shear flows can initiate mixing via the Kelvin-Helmholtz (KH) instability and may eventually drive a transition to turbulence. We present two dedicated shear flow experiments that created subsonic and supersonic shear layers in HED plasmas. In the subsonic case the Omega laser was used to drive a shock wave along a rippled plastic interface, which subsequently rolled-upped into large KH vortices. In the supersonic shear experiment the Nike laser was used to drive Al plasma across a low-density foam surface also seeded with a ripple. Unlike the subsonic case, detached shocks developed around the ripples in response to the supersonic Al flow.

  12. Neuroimaging and Neuroenergetics: Brain Activations as Information-Driven Reorganization of Energy Flows

    ERIC Educational Resources Information Center

    Strelnikov, Kuzma

    2010-01-01

    There is increasing focus on the neurophysiological underpinnings of brain activations, giving birth to an emerging branch of neuroscience--neuroenergetics. However, no common definition of "brain activation" exists thus far. In this article, we define brain activation as the information-driven reorganization of energy flows in a population of…

  13. Characterization of changes in commercial building structure, equipment, and occupants: End-Use Load and Consumer Assessment Program

    SciTech Connect

    Lucas, R.G.; Taylor, Z.T.; Miller, N.E.; Pratt, R.G.

    1990-12-01

    Changes in commercial building structure, equipment, and occupants result in changes in building energy use. The frequency and magnitude of those changes have substantial implications for conservation programs and resource planning. For example, changes may shorten the useful lifetime of a conservation measure as well as impact the savings from that measure. This report summarizes the frequency of changes in a commercial building sample that was end-use metered under the End-Use Load and Consumer Assessment Program (ELCAP). The sample includes offices, dry good retails, groceries, restaurants, warehouses, schools, and hotels. Two years of metered data, site visit records, and audit data were examined for evidence of building changes. The observed changes were then classified into 12 categories, which included business type, equipment, remodel, vacancy, and operating schedule. The analysis characterized changes in terms of frequency of types of change; relationship to building vintage and floor area; and variation by building type. The analysis also examined the energy impacts of various changes. The analysis determined that the rate of change in commercial buildings is high--50% of the buildings experienced one type of change during the 2 years for which monitoring data were examined. Equipment changes were found to be most frequent in offices and retail stores. Larger, older office buildings tend to experience a wider variety of changes more frequently than the smaller, newer buildings. Key findings and observations are presented in Section 2. Section 3 provides the underlying motivation and objectives. In Section 4, the methodology used is documented, including the commercial building sample and the data sources used. Included are the definitions of change events and the overall approach taken. Results are analyzed in Section 5, with additional technical details in Appendixes. 2 refs., 46 figs., 22 tabs. (JF)

  14. Experiment of Flow Control Using Laser Energy Deposition Around High Speed Propulsion System

    NASA Astrophysics Data System (ADS)

    Lee, HyoungJin; Jeung, InSeuck; Lee, SangHun; Kim, Seihwan

    2011-11-01

    An experimental investigation was conducted to examine the effect of a pulsed Nd:YAG laser energy deposition on the shock structures in supersonic/hypersonic flow and quiescent air. The effect of the laser energy and pressure in the blast wave generation were also investigated. As a result, the strength of plasma and blast wave becomes stronger as pressure or laser energy increase. And the breakdown threshold of air by laser energy deposition is 0.015 bar at 508 mJ laser energy, the blast wave threshold generation in air by laser energy deposition is 0.100 bar at same laser energy. As qualitative analysis, schlieren images are also obtained. After the series of experiments, the effect of laser energy deposition (LED) on high speed flow around the shock—shock interaction created by a wedge and blunt body. By LED, the structure of shock—shock interaction was collapsed momentary and the pressure of the stagnation point was fluctuated while interference of wave.

  15. Alpha-helices direct excitation energy flow in the Fenna Matthews Olson protein.

    PubMed

    Müh, Frank; Madjet, Mohamed El-Amine; Adolphs, Julia; Abdurahman, Ayjamal; Rabenstein, Björn; Ishikita, Hiroshi; Knapp, Ernst-Walter; Renger, Thomas

    2007-10-23

    In photosynthesis, light is captured by antenna proteins. These proteins transfer the excitation energy with almost 100% quantum efficiency to the reaction centers, where charge separation takes place. The time scale and pathways of this transfer are controlled by the protein scaffold, which holds the pigments at optimal geometry and tunes their excitation energies (site energies). The detailed understanding of the tuning of site energies by the protein has been an unsolved problem since the first high-resolution crystal structure of a light-harvesting antenna appeared >30 years ago [Fenna RE, Matthews BW (1975) Nature 258:573-577]. Here, we present a combined quantum chemical/electrostatic approach to compute site energies that considers the whole protein in atomic detail and provides the missing link between crystallography and spectroscopy. The calculation of site energies of the Fenna-Matthews-Olson protein results in optical spectra that are in quantitative agreement with experiment and reveals an unexpectedly strong influence of the backbone of two alpha-helices. The electric field from the latter defines the direction of excitation energy flow in the Fenna-Matthews-Olson protein, whereas the effects of amino acid side chains, hitherto thought to be crucial, largely compensate each other. This result challenges the current view of how energy flow is regulated in pigment-protein complexes and demonstrates that attention has to be paid to the backbone architecture. PMID:17940020

  16. Energy and materials flows in the production of liquid and gaseous oxygen

    SciTech Connect

    Shen, S.; Wolsky, A.M.

    1980-08-01

    Liquid and gaseous oxygen is produced in an energy-intensive air separation processo that also generates nitrogen. More than 65% of the cost of oxygen is attributable to energy costs. Energy use and materials flows are analyzed for various air separation methods. Effective approaches to energy and material conservation in air separation plants include efficient removal of contaminants (carbon dioxide and water), centralization of air products user-industries so that large air separation plants are cost-effective and the energy use in transportation is minimized, and increased production of nitrogen. Air separation plants can produce more than three times more nitrogen than oxygen, but present markets demand, at most, only 1.5 times more. Full utlization of liquid and gaseous nitrogen should be encouraged, so that the wasted separation energy is minimized. There are potential markets for nitrogen in, for example, cryogenic separation of metallic and plastic wastes, cryogenic particle size reduction, and production of ammonia for fertilizer.

  17. A Thermally-Regenerative Ammonia-Based Flow Battery for Electrical Energy Recovery from Waste Heat.

    PubMed

    Zhu, Xiuping; Rahimi, Mohammad; Gorski, Christopher A; Logan, Bruce

    2016-04-21

    Large amounts of low-grade waste heat (temperatures <130 °C) are released during many industrial, geothermal, and solar-based processes. Using thermally-regenerative ammonia solutions, low-grade thermal energy can be converted to electricity in battery systems. To improve reactor efficiency, a compact, ammonia-based flow battery (AFB) was developed and tested at different solution concentrations, flow rates, cell pairs, and circuit connections. The AFB achieved a maximum power density of 45 W m(-2) (15 kW m(-3) ) and an energy density of 1260 Wh manolyte (-3) , with a thermal energy efficiency of 0.7 % (5 % relative to the Carnot efficiency). The power and energy densities of the AFB were greater than those previously reported for thermoelectrochemical and salinity-gradient technologies, and the voltage or current could be increased using stacked cells. These results demonstrated that an ammonia-based flow battery is a promising technology to convert low-grade thermal energy to electricity.

  18. Bounded energy states in homogeneous turbulent shear flow: An alternative view

    NASA Technical Reports Server (NTRS)

    Bernard, Peter S.; Speziale, Charles G.

    1990-01-01

    The equilibrium structure of homogeneous turbulent shear flow is investigated from a theoretical standpoint. Existing turbulence models, in apparent agreement with physical and numerical experiments, predict an unbounded exponential time growth of the turbulent kinetic energy and dissipation rate; only the anisotropy tensor and turbulent time scale reach a structural equilibrium. It is shown that if vortex stretching is accounted for in the dissipation rate transport equation, then there can exist equilibrium solutions, with bounded energy states, where the turbulence production is balanced by its dissipation. Illustrative calculations are present for a k-epsilon model modified to account for vortex stretching. The calculations indicate an initial exponential time growth of the turbulent kinetic energy and dissipation rate for elapsed times that are as large as those considered in any of the previously conducted physical or numerical experiments on homogeneous shear flow. However, vortex stretching eventually takes over and forces a production-equals-dissipation equilibrium with bounded energy states. The validity of this result is further supported by an independent theoretical argument. It is concluded that the generally accepted structural equilibrium for homogeneous shear flow with unbounded component energies is in need of re-examination.

  19. Energy Harvesting for Micropower Applications by Flow-Induced Flutter of an Inverted Piezoelectric Flag

    NASA Astrophysics Data System (ADS)

    Shoele, Kourosh; Mittal, Rajat

    2015-11-01

    Piezoelectric flexible flags can be used to continuously generate energy for small-scale sensor used in a wide variety of applications ranging from measurement/monitoring of environmental conditions (outdoors or indoors) to in-situ tracking of wild animals. Here, we study the energy harvesting performance as well as the flow-structure interaction of an inverted piezoelectric flag. We use a coupled fluid-structure-electric solver to examine the dynamic response of the inverted flag as well as the associated vortical characteristics with different inertia and bending stiffness. Simulations indicate that large amplitude vibrations can be achieved over a large range of parameters over which lock-on between the flag flutter and the intrinsic wake shedding occurs. The effects of initial inclination of the flag to the prevailing flow as well as Reynolds number of the flow are explored, and the effect of piezoelectric material parameters on the energy harvesting performance of this flutter state is examined in detail. The maximum energy efficiency occurs when there is a match between the intrinsic timescales of flutter and the piezoelectric circuit. The simulations are used to formulate a scaling law that could be used to predict the energy harvesting performance of such devices. The support for this study comes from AFSOR, NSF, EPRI and Johns Hopkins E2SHI Seed Grant.

  20. A Thermally-Regenerative Ammonia-Based Flow Battery for Electrical Energy Recovery from Waste Heat.

    PubMed

    Zhu, Xiuping; Rahimi, Mohammad; Gorski, Christopher A; Logan, Bruce

    2016-04-21

    Large amounts of low-grade waste heat (temperatures <130 °C) are released during many industrial, geothermal, and solar-based processes. Using thermally-regenerative ammonia solutions, low-grade thermal energy can be converted to electricity in battery systems. To improve reactor efficiency, a compact, ammonia-based flow battery (AFB) was developed and tested at different solution concentrations, flow rates, cell pairs, and circuit connections. The AFB achieved a maximum power density of 45 W m(-2) (15 kW m(-3) ) and an energy density of 1260 Wh manolyte (-3) , with a thermal energy efficiency of 0.7 % (5 % relative to the Carnot efficiency). The power and energy densities of the AFB were greater than those previously reported for thermoelectrochemical and salinity-gradient technologies, and the voltage or current could be increased using stacked cells. These results demonstrated that an ammonia-based flow battery is a promising technology to convert low-grade thermal energy to electricity. PMID:26990485

  1. Drag Reduction by Laser-Plasma Energy Addition in Hypersonic Flow

    SciTech Connect

    Oliveira, A. C.; Minucci, M. A. S.; Toro, P. G. P.; Chanes, J. B. Jr; Myrabo, L. N.

    2008-04-28

    An experimental study was conducted to investigate the drag reduction by laser-plasma energy addition in a low density Mach 7 hypersonic flow. The experiments were conducted in a shock tunnel and the optical beam of a high power pulsed CO{sub 2} TEA laser operating with 7 J of energy and 30 MW peak power was focused to generate the plasma upstream of a hemispherical model installed in the tunnel test section. The non-intrusive schlieren optical technique was used to visualize the effects of the energy addition to hypersonic flow, from the plasma generation until the mitigation of the shock wave profile over the model surface. Aside the optical technique, a piezoelectric pressure transducer was used to measure the impact pressure at stagnation point of the hemispherical model and the pressure reduction could be observed.

  2. Inlet Diameter and Flow Volume Effects on Separation and Energy Efficiency of Hydrocyclones

    NASA Astrophysics Data System (ADS)

    Erikli, Ş.; Olcay, A. B.

    2015-08-01

    This study investigates hydrocyclone performance of an oil injected screw compressor. Especially, the oil separation efficiency of a screw compressor plays a significant role for air quality and non-stop working hour of compressors has become an important issue when the efficiency in energy is considered. In this study, two separation efficiency parameters were selected to be hydrocyclone inlet diameter and flow volume height between oil reservoir surface and top of the hydrocyclone. Nine different cases were studied in which cyclone inlet diameter and flow volume height between oil reservoir surface and top were investigated in regards to separation and energy performance aspects and the effect of the parameters on the general performance appears to be causing powerful influence. Flow inside the hydrocyclone geometry was modelled by Reynolds Stress Model (RSM) and hydro particles were tracked by Discrete Phase Model (DPM). Besides, particle break up was modelled by the Taylor Analogy Breakup (TAB) model. The reversed vortex generation was observed at different planes. The upper limit of the inlet diameter of the cyclone yields the centrifugal force on particles to decrease while the flow becomes slower; and the larger diameter implies slower flow. On the contrary, the lower limit is increment in speed causes breakup problems that the particle diameters become smaller; consequently, it is harder to separate them from gas.

  3. Preliminary study of high energy density Zn/Ni flow batteries

    NASA Astrophysics Data System (ADS)

    Liu, Jin; Wang, Yan

    2015-10-01

    The escalation of power system promotes the development of energy storage technologies (ESTs). Among all of ESTs, battery technologies develop quickly and diversely because of its huge application market. Aqueous redox flow batteries (RFBs) are very attractive to customers in the energy grid system, and their noticeable technological innovations in past decades are driving them to gradually replace the conventional ESTs under certain circumstance. Here, the first fully-flow-able zinc-nickel flow battery (ZNFB) is preliminary reported in this paper, and its superior performance is supposed to be suitable for both large-scale storage need and carry-on powertrain in cars. Through using semi-solid fuel cell (SSFC) technology, we incorporates the beneficial features of Zn/Ni chemistry (essentially sustainable, eco-friendly and deposit-abundant) into RFB structure to make a "hybrid" flow battery system, which can take the advantage of both. The relationship between carbon loading and suspension conductivity is determined. Electrochemical properties of ZNFB as static test, cycling test, and fully flowing test are studied to demonstrate our design.

  4. Wave energy and wave-induced flow reduction by full-scale model Posidonia oceanica seagrass

    NASA Astrophysics Data System (ADS)

    Manca, E.; Cáceres, I.; Alsina, J. M.; Stratigaki, V.; Townend, I.; Amos, C. L.

    2012-12-01

    This paper presents results from experiments in a large flume on wave and flow attenuation by a full-scale artificial Posidonia oceanica seagrass meadow in shallow water. Wave height and in-canopy wave-induced flows were reduced by the meadow under all tested regular and irregular wave conditions, and were affected by seagrass density, submergence and distance from the leading edge. The energy of irregular waves was reduced at all components of the spectra, but reduction was greater at the peak spectral frequency. Energy dissipation factors were largest for waves with small orbital amplitudes and at low wave Reynolds numbers. An empirical model, commonly applied to predict friction factors by rough beds, proved applicable to the P. oceanica bed. However at the lowest Reynolds numbers, under irregular waves, the data deviated significantly from the model. In addition, the wave-induced flow dissipation in the lower canopy increased with increasing wave orbital amplitude and increasing density of the mimics. The analysis of the wave-induced flow spectra confirm this trend: the reduction of flow was greatest at the longer period component of the spectra. Finally, we discuss the implications of these findings for sediment dynamics and the role of P. oceanica beds in protecting the shore from erosion.

  5. Scale-to-scale energy transfer in mixing flow induced by the Richtmyer-Meshkov instability

    NASA Astrophysics Data System (ADS)

    Liu, Han; Xiao, Zuoli

    2016-05-01

    The Richtmyer-Meshkov instability (RMI) mixing flow induced by a planar shock wave of Mach 1.6 is investigated using direct numerical simulation method. Interfacial perturbations of different scales between air and sulfur hexafluoride are introduced to study the effect of the initial conditions. Focus is placed on the analysis of the scale-to-scale transfer of kinetic energy in both Fourier and physical spaces. The kinetic energy injected from the perturbation scales is transferred to both larger and smaller scales in an average sense within the inner mixing zone (IMZ) at early times and is mainly passed down into smaller scales at the late stage. The physical-space energy flux due to the subgrid-scale (SGS) stress is studied using a filtering approach in order to shed light on the physical origin of the scale-to-scale kinetic energy transfer. It is found that the pointwise SGS energy flux is highly correlated with the local spike and bubble structures in the IMZ. Moreover, it turns out that the mean SGS energy flux is mainly ascribed to the component in the direction of shock wave propagation. An analysis using the method of conditional averaging manifests that the generation of local SGS energy flux is associated with the property of the surrounding flow induced by quadrupolar or dipolar vortex structures.

  6. International energy trade impacts on water resource crises: an embodied water flows perspective

    NASA Astrophysics Data System (ADS)

    Zhang, J. C.; Zhong, R.; Zhao, P.; Zhang, H. W.; Wang, Y.; Mao, G. Z.

    2016-07-01

    Water and energy are coupled in intimate ways (Siddiqi and Anadon 2011 Energy Policy 39 4529-40), which is amplified by international energy trade. The study shows that the total volume of energy related international embodied water flows averaged 6298 Mm3 yr-1 from 1992-2010, which represents 10% of the water used for energy production including oil, coal, gas and electricity production. This study calculates embodied water import and export status of 219 countries from 1992 to 2010 and embodied water flow changes of seven regions over time (1992/2000/2010). In addition, the embodied water net export risk-crisis index and net embodied water import benefit index are established. According to the index system, 33 countries export vast amounts of water who have a water shortage, which causes water risk and crisis related to energy trade. While 29 countries abate this risk due to their rich water resource, 45 countries import embodied water linked to energy imports. Based on the different status of countries studied, the countries were classified into six groups with different policy recommendations.

  7. International energy trade impacts on water resource crises: an embodied water flows perspective

    NASA Astrophysics Data System (ADS)

    Zhang, J. C.; Zhong, R.; Zhao, P.; Zhang, H. W.; Wang, Y.; Mao, G. Z.

    2016-07-01

    Water and energy are coupled in intimate ways (Siddiqi and Anadon 2011 Energy Policy 39 4529–40), which is amplified by international energy trade. The study shows that the total volume of energy related international embodied water flows averaged 6298 Mm3 yr‑1 from 1992–2010, which represents 10% of the water used for energy production including oil, coal, gas and electricity production. This study calculates embodied water import and export status of 219 countries from 1992 to 2010 and embodied water flow changes of seven regions over time (1992/2000/2010). In addition, the embodied water net export risk-crisis index and net embodied water import benefit index are established. According to the index system, 33 countries export vast amounts of water who have a water shortage, which causes water risk and crisis related to energy trade. While 29 countries abate this risk due to their rich water resource, 45 countries import embodied water linked to energy imports. Based on the different status of countries studied, the countries were classified into six groups with different policy recommendations.

  8. Scale-to-scale energy transfer in mixing flow induced by the Richtmyer-Meshkov instability.

    PubMed

    Liu, Han; Xiao, Zuoli

    2016-05-01

    The Richtmyer-Meshkov instability (RMI) mixing flow induced by a planar shock wave of Mach 1.6 is investigated using direct numerical simulation method. Interfacial perturbations of different scales between air and sulfur hexafluoride are introduced to study the effect of the initial conditions. Focus is placed on the analysis of the scale-to-scale transfer of kinetic energy in both Fourier and physical spaces. The kinetic energy injected from the perturbation scales is transferred to both larger and smaller scales in an average sense within the inner mixing zone (IMZ) at early times and is mainly passed down into smaller scales at the late stage. The physical-space energy flux due to the subgrid-scale (SGS) stress is studied using a filtering approach in order to shed light on the physical origin of the scale-to-scale kinetic energy transfer. It is found that the pointwise SGS energy flux is highly correlated with the local spike and bubble structures in the IMZ. Moreover, it turns out that the mean SGS energy flux is mainly ascribed to the component in the direction of shock wave propagation. An analysis using the method of conditional averaging manifests that the generation of local SGS energy flux is associated with the property of the surrounding flow induced by quadrupolar or dipolar vortex structures. PMID:27300983

  9. Magnetic resonance temperature imaging-based quantification of blood flow-related energy losses.

    PubMed

    Dillon, Christopher; Roemer, Robert; Payne, Allison

    2015-07-01

    This study presents a new approach for evaluating bioheat transfer equation (BHTE) models used in treatment planning, control and evaluation of all thermal therapies. First, 3D magnetic resonance temperature imaging (MRTI) data are used to quantify blood flow-related energy losses, including the effects of perfusion and convection. Second, this information is used to calculate parameters of a BHTE model: in this paper the widely used Pennes BHTE. As a self-consistency check, the BHTE parameters are utilized to predict the temperatures from which they were initially derived. The approach is evaluated with finite-difference simulations and implemented experimentally with focused ultrasound heating of an ex vivo porcine kidney perfused at 0, 20 and 40 ml/min (n = 4 each). The simulation results demonstrate accurate quantification of blood flow-related energy losses, except in regions of sharp blood flow discontinuities, where the transitions are spatially smoothed. The smoothed transitions propagate into estimates of the Pennes perfusion parameter but have limited effect on the accuracy of temperature predictions using these estimates. Longer acquisition time periods mitigate the effects of MRTI noise, but worsen the effect of flow discontinuities. For the no-flow kidney experiments the estimates of a uniform, constant Pennes perfusion parameter are approximately zero, and at 20 and 40 ml/min the average estimates increase with flow rate to 3.0 and 4.2 kg/m(3) /s, respectively. When Pennes perfusion parameter values are allowed to vary spatially, but remain temporally constant, BHTE temperature predictions are more accurate than when using spatially uniform, constant Pennes perfusion values, with reductions in RMSE values of up to 79%. Locations with large estimated perfusion values correspond to high flow regions of the kidney observed in T1 -weighted MR images. This novel, MRTI-based technique holds promise for improving understanding of thermal therapy biophysics

  10. Transient river flow into a fjord and its control of plume energy partitioning

    NASA Astrophysics Data System (ADS)

    O'Callaghan, J. M.; Stevens, C. L.

    2015-05-01

    The influence of variable inflows on near-field plume dynamics and energy partitioning was examined using observations of a controlled flow into Doubtful Sound, New Zealand. The high temporal changes in flows passing through the Manapouri hydroelectric power station mimic the magnitude and variability seen in small mountainous river systems (SMRS) globally. The variable flow coupled with strong vertical density gradients akin to ambient conditions in coastal systems enabled plume behavior to be characterized for differing flow, wind, and tidal inputs in a quasi-idealized "laboratory" system. Comparisons of the frequency distributions of energy for different forcing conditions showed that baroclinic and barotropic processes were closely intertwined for transient forcing. The periodicity of density due to tidal oscillations was initially absent; headwaters of the fjord absorbed the momentum when inflows were substantially increased from the mean of ˜420 m3 s-1. From the buoyancy frequency squared N2, six events were identified when N2 was greater than 0.07 s-2. Seven occurrences of supercritical flow (Froude number, Fri > 1) and associated transitions to subcritical flow were observed over the duration of mooring deployment. Transient inflows induced internal hydraulic jumps in the near-field region which lead to a rapid breakdown of vertical stratification. The horizontal length scale of an internal hydraulic jump is O (1 km). Not all transitions from Fri > 1 to <1 are explained by transient forcing and the role of strong, up-fjord wind stress is likely to initiate supercritical flows via setup at the head of the fjord.

  11. Harvesting energy from a water flow through ionic polymer metal composites' buckling

    NASA Astrophysics Data System (ADS)

    Cellini, Filippo; Cha, Youngsu; Porfiri, Maurizio

    2014-03-01

    This study seeks to investigate the feasibility of energy harvesting from mechanical buckling of ionic polymer metal composites (IPMCs) induced by a steady fluid flow. In particular, we propose a harvesting device composed of a paddle wheel, a slider-crank mechanism, and two IPMCs clamped at both their ends. We test the system in a water tunnel to estimate the effects of the flow speed and the shunting resistance on power harvesting. The classical post-buckling theory of inextensible rods is utilized, in conjunction with a black-box model for IPMC sensing, to interpret experimental results.

  12. Electron-temperature and energy-flow history in an imploding plasma.

    PubMed

    Gregorian, L; Kroupp, E; Davara, G; Starobinets, A; Fisher, V I; Bernshtam, V A; Ralchenko, Yu V; Maron, Y; Fisher, A; Hoffmann, D H H

    2005-05-01

    The time-dependent radial distribution of the electron temperature in a 0.6 micros, 220-kA gas-puff z-pinch plasma is studied using spatially-resolved observations of line emission from singly to fivefold ionized oxygen ions during the plasma implosion, up to 50 ns before maximum compression. The temperature obtained, together with the previously determined radial distributions of the electron density, plasma radial velocity, and magnetic field, allows for studying the history of the magnetic-field energy coupling to the plasma by comparing the energy deposition and dissipation rates in the plasma. It is found that at this phase of the implosion, approximately 65% of the energy deposited in the plasma is imparted to the plasma radial flow, with the rest of the energy being converted into internal energy and radiation. PMID:16089655

  13. Energy dynamics in the Richtmyer-Meshkov instability induced turbulent mixing flow

    NASA Astrophysics Data System (ADS)

    Xiao, Zuoli; Liu, Han

    2014-11-01

    The Richtmyer-Meshkov instability (RMI) induced turbulent mixing flow in a shock tube is numerically investigated by using direct numerical simulation based on an effective in-house high-order turbulence solver (HOTS). The energy transfer and transport characteristics are studied both before and after re-shock. The celebrated Kolmogorov -5/3 spectrum can be observed in a long inertial subrange during the development of the turbulent mixing zone (TMZ). Insight is taken into the underlying mechanism by evaluating the energy-budget equations. A posteriori analysis of the influence of subgrid scales on resolved motions also gives a consistent picture of energy transfer in the RMI-induced turbulent mixing. Moreover, the kinetic energy cascade in the TMZ is discussed by using Favre filtering approach in physical space. A nonlinear vortex-stretching model for the subgrid-scale stress serves to explain the underlying mechanism of the energy cascade in the RMI-induced turbulence.

  14. Electron-temperature and energy-flow history in an imploding plasma.

    PubMed

    Gregorian, L; Kroupp, E; Davara, G; Starobinets, A; Fisher, V I; Bernshtam, V A; Ralchenko, Yu V; Maron, Y; Fisher, A; Hoffmann, D H H

    2005-05-01

    The time-dependent radial distribution of the electron temperature in a 0.6 micros, 220-kA gas-puff z-pinch plasma is studied using spatially-resolved observations of line emission from singly to fivefold ionized oxygen ions during the plasma implosion, up to 50 ns before maximum compression. The temperature obtained, together with the previously determined radial distributions of the electron density, plasma radial velocity, and magnetic field, allows for studying the history of the magnetic-field energy coupling to the plasma by comparing the energy deposition and dissipation rates in the plasma. It is found that at this phase of the implosion, approximately 65% of the energy deposited in the plasma is imparted to the plasma radial flow, with the rest of the energy being converted into internal energy and radiation.

  15. A chemistry and material perspective on lithium redox flow batteries towards high-density electrical energy storage.

    PubMed

    Zhao, Yu; Ding, Yu; Li, Yutao; Peng, Lele; Byon, Hye Ryung; Goodenough, John B; Yu, Guihua

    2015-11-21

    Electrical energy storage system such as secondary batteries is the principle power source for portable electronics, electric vehicles and stationary energy storage. As an emerging battery technology, Li-redox flow batteries inherit the advantageous features of modular design of conventional redox flow batteries and high voltage and energy efficiency of Li-ion batteries, showing great promise as efficient electrical energy storage system in transportation, commercial, and residential applications. The chemistry of lithium redox flow batteries with aqueous or non-aqueous electrolyte enables widened electrochemical potential window thus may provide much greater energy density and efficiency than conventional redox flow batteries based on proton chemistry. This Review summarizes the design rationale, fundamentals and characterization of Li-redox flow batteries from a chemistry and material perspective, with particular emphasis on the new chemistries and materials. The latest advances and associated challenges/opportunities are comprehensively discussed. PMID:26265165

  16. A chemistry and material perspective on lithium redox flow batteries towards high-density electrical energy storage.

    PubMed

    Zhao, Yu; Ding, Yu; Li, Yutao; Peng, Lele; Byon, Hye Ryung; Goodenough, John B; Yu, Guihua

    2015-11-21

    Electrical energy storage system such as secondary batteries is the principle power source for portable electronics, electric vehicles and stationary energy storage. As an emerging battery technology, Li-redox flow batteries inherit the advantageous features of modular design of conventional redox flow batteries and high voltage and energy efficiency of Li-ion batteries, showing great promise as efficient electrical energy storage system in transportation, commercial, and residential applications. The chemistry of lithium redox flow batteries with aqueous or non-aqueous electrolyte enables widened electrochemical potential window thus may provide much greater energy density and efficiency than conventional redox flow batteries based on proton chemistry. This Review summarizes the design rationale, fundamentals and characterization of Li-redox flow batteries from a chemistry and material perspective, with particular emphasis on the new chemistries and materials. The latest advances and associated challenges/opportunities are comprehensively discussed.

  17. Minimum energy as the general form of critical flow and maximum flow efficiency and for explaining variations in river channel pattern

    NASA Astrophysics Data System (ADS)

    Huang, He Qing; Chang, Howard H.; Nanson, Gerald C.

    2004-04-01

    Although the Bélanger-Böss theorem of critical flow has been widely applied in open channel hydraulics, it was derived from the laws governing ideal frictionless flow. This study explores a more general expression of this theorem and examines its applicability to flow with friction and sediment transport. It demonstrates that the theorem can be more generally presented as the principle of minimum energy (PME), with maximum efficiency of energy use and minimum friction or minimum energy dissipation as its equivalents. Critical flow depth under frictionless conditions, the best hydraulic section where friction is introduced, and the most efficient alluvial channel geometry where both friction and sediment transport apply are all shown to be the products of PME. Because PME in liquids characterizes the stationary state of motion in solid materials, flow tends to rapidly expend excess energy when more than minimally demanded energy is available. This leads to the formation of relatively stable but dynamic energy-consuming meandering and braided channel planforms and explains the existence of various extremal hypotheses.

  18. Measurement of the Turbulence Kinetic Energy Budget of a Turbulent Planar Wake Flow in Pressure Gradients

    NASA Technical Reports Server (NTRS)

    Liu, Xiao-Feng; Thomas, Flint O.; Nelson, Robert C.

    2001-01-01

    Turbulence kinetic energy (TKE) is a very important quantity for turbulence modeling and the budget of this quantity in its transport equation can provide insight into the flow physics. Turbulence kinetic energy budget measurements were conducted for a symmetric turbulent wake flow subjected to constant zero, favorable and adverse pressure gradients in year-three of research effort. The purpose of this study is to clarify the flow physics issues underlying the demonstrated influence of pressure gradient on wake development and provide experimental support for turbulence modeling. To ensure the reliability of these notoriously difficult measurements, the experimental procedure was carefully designed on the basis of an uncertainty analysis. Four different approaches, based on an isotropic turbulence assumption, a locally axisymmetric homogeneous turbulence assumption, a semi-isotropy assumption and a forced balance of the TKE equation, were applied for the estimate of the dissipation term. The pressure transport term is obtained from a forced balance of the turbulence kinetic energy equation. This report will present the results of the turbulence kinetic energy budget measurement and discuss their implication on the development of strained turbulent wakes.

  19. Power flow as a complement to statistical energy analysis and finite element analysis

    NASA Technical Reports Server (NTRS)

    Cuschieri, J. M.

    1987-01-01

    Present methods of analysis of the structural response and the structure-borne transmission of vibrational energy use either finite element (FE) techniques or statistical energy analysis (SEA) methods. The FE methods are a very useful tool at low frequencies where the number of resonances involved in the analysis is rather small. On the other hand SEA methods can predict with acceptable accuracy the response and energy transmission between coupled structures at relatively high frequencies where the structural modal density is high and a statistical approach is the appropriate solution. In the mid-frequency range, a relatively large number of resonances exist which make finite element method too costly. On the other hand SEA methods can only predict an average level form. In this mid-frequency range a possible alternative is to use power flow techniques, where the input and flow of vibrational energy to excited and coupled structural components can be expressed in terms of input and transfer mobilities. This power flow technique can be extended from low to high frequencies and this can be integrated with established FE models at low frequencies and SEA models at high frequencies to form a verification of the method. This method of structural analysis using power flo and mobility methods, and its integration with SEA and FE analysis is applied to the case of two thin beams joined together at right angles.

  20. A TECHNOLOGY ASSESSMENT AND FEASIBILITY EVALUATION OF NATURAL GAS ENERGY FLOW MEASUREMENT ALTERNATIVES

    SciTech Connect

    Kendricks A. Behring II; Eric Kelner; Ali Minachi; Cecil R. Sparks; Thomas B. Morrow; Steven J. Svedeman

    1999-01-01

    Deregulation and open access in the natural gas pipeline industry has changed the gas business environment towards greater reliance on local energy flow rate measurement. What was once a large, stable, and well-defined source of natural gas is now a composite from many small suppliers with greatly varying gas compositions. Unfortunately, the traditional approach to energy flow measurement [using a gas chromatograph (GC) for composition assay in conjunction with a flow meter] is only cost effective for large capacity supplies (typically greater than 1 to 30 million scfd). A less costly approach will encourage more widespread use of energy measurement technology. In turn, the US will benefit from tighter gas inventory control, more efficient pipeline and industrial plant operations, and ultimately lower costs to the consumer. An assessment of the state and direction of technology for natural gas energy flow rate measurement is presented. The alternative technologies were ranked according to their potential to dramatically reduce capital and operating and maintenance (O and M) costs, while improving reliability and accuracy. The top-ranked technologies take an unconventional inference approach to the energy measurement problem. Because of that approach, they will not satisfy the fundamental need for composition assay, but have great potential to reduce industry reliance on the GC. Technological feasibility of the inference approach was demonstrated through the successful development of data correlations that relate energy measurement properties (molecular weight, mass-based heating value, standard density, molar ideal gross heating value, standard volumetric heating value, density, and volume-based heating value) to three inferential properties: standard sound speed, carbon dioxide concentration, and nitrogen concentration (temperature and pressure are also required for the last two). The key advantage of this approach is that inexpensive on-line sensors may be used

  1. Geography and end use drive the diversification of worldwide winter rye populations.

    PubMed

    Parat, Florence; Schwertfirm, Grit; Rudolph, Ulrike; Miedaner, Thomas; Korzun, Viktor; Bauer, Eva; Schön, Chris-Carolin; Tellier, Aurélien

    2016-01-01

    To meet the current challenges in human food production, improved understanding of the genetic diversity of crop species that maximizes the selection efficacy in breeding programs is needed. The present study offers new insights into the diversity, genetic structure and demographic history of cultivated rye (Secale cereale L.). We genotyped 620 individuals from 14 global rye populations with a different end use (grain or forage) at 32 genome-wide simple sequence repeat markers. We reveal the relationships among these populations, their sizes and the timing of domestication events using population genetics and model-based inference with approximate Bayesian computation. Our main results demonstrate (i) a high within-population variation and genetic diversity, (ii) an unexpected absence of reduction in diversity with an increasing improvement level and (iii) patterns suggestive of multiple domestication events. We suggest that the main drivers of diversification of winter rye are the end use of rye in two early regions of cultivation: rye forage in the Mediterranean area and grain in northeast Europe. The lower diversity and stronger differentiation of eastern European populations were most likely due to more intensive cultivation and breeding of rye in this region, in contrast to the Mediterranean region where it was considered a secondary crop or even a weed. We discuss the relevance of our results for the management of gene bank resources and the pitfalls of inference methods applied to crop domestication due to violation of model assumptions and model complexity.

  2. Inter-phase heat transfer and energy coupling in turbulent dispersed multiphase flows

    NASA Astrophysics Data System (ADS)

    Ling, Y.; Balachandar, S.; Parmar, M.

    2016-03-01

    The present paper addresses important fundamental issues of inter-phase heat transfer and energy coupling in turbulent dispersed multiphase flows through scaling analysis. In typical point-particle or two-fluid approaches, the fluid motion and convective heat transfer at the particle scale are not resolved and the momentum and energy coupling between fluid and particles are provided by proper closure models. By examining the kinetic energy transfer due to the coupling forces from the macroscale to microscale fluid motion, closure models are obtained for the contributions of the coupling forces to the energy coupling. Due to the inviscid origin of the added-mass force, its contribution to the microscale kinetic energy does not contribute to dissipative transfer to fluid internal energy as was done by the quasi-steady force. Time scale analysis shows that when the particle is larger than a critical diameter, the diffusive-unsteady kernel decays at a time scale that is smaller than the Kolmogorov time scale. As a result, the computationally costly Basset-like integral form of diffusive-unsteady heat transfer can be simplified to a non-integral form. Conventionally, the fluid-to-particle volumetric heat capacity ratio is used to evaluate the relative importance of the unsteady heat transfer to the energy balance of the particles. Therefore, for gas-particle flows, where the fluid-to-particle volumetric heat capacity ratio is small, unsteady heat transfer is usually ignored. However, the present scaling analysis shows that for small fluid-to-particle volumetric heat capacity ratio, the importance of the unsteady heat transfer actually depends on the ratio between the particle size and the Kolmogorov scale. Furthermore, the particle mass loading multiplied by the heat capacity ratio is usually used to estimate the importance of the thermal two-way coupling effect. Through scaling argument, improved estimates are established for the energy coupling parameters of each

  3. Vertical dipole above a dielectric or metallic half space: Energy-flow considerations.

    PubMed

    Berman, P R; Zandbergen, S R; Khitrova, G

    2015-07-01

    The emission pattern from a classical dipole located above and oriented perpendicular to a metallic or dielectric half space is calculated for a dipole driven at constant amplitude. Emphasis is placed on the fields in the metal or dielectric. It is shown that the radial Poynting vector in the metal points inwards when the frequency of the dipole is below the surface plasmon resonance frequency. In this case, energy actually flows out of the interface at small radii and the power entering the metal can actually oscillate as a function of radius. The Joule heating in the metal is also calculated for a cylindrical volume in the metal. When the metal is replaced by a dielectric having permittivity less than that of the medium in which the dipole is immersed, it is found that energy flows out of the interface for sufficiently large radii, a result reminiscent of the Goos-Hänchen effect. PMID:26274297

  4. Two-stage acceleration of interstellar ions driven by high-energy lepton plasma flows

    NASA Astrophysics Data System (ADS)

    Cui, YunQian; Sheng, ZhengMing; Lu, QuanMing; Li, YuTong; Zhang, Jie

    2015-10-01

    We present the particle-in-cell (PIC) simulation results of the interaction of a high-energy lepton plasma flow with background electron-proton plasma and focus on the acceleration processes of the protons. It is found that the acceleration follows a two-stage process. In the first stage, protons are significantly accelerated transversely (perpendicular to the lepton flow) by the turbulent magnetic field "islands" generated via the strong Weibel-type instabilities. The accelerated protons shows a perfect inverse-power energy spectrum. As the interaction continues, a shockwave structure forms and the protons in front of the shockwave are reflected at twice of the shock speed, resulting in a quasi-monoenergetic peak located near 200 MeV under the simulation parameters. The presented scenario of ion acceleration may be relevant to cosmic-ray generation in some astrophysical environments.

  5. A theoretical analysis of fluid flow and energy transport in hydrothermal systems

    USGS Publications Warehouse

    Faust, Charles R.; Mercer, James W.

    1977-01-01

    A mathematical derivation for fluid flow and energy transport in hydrothermal systems is presented. Specifically, the mathematical model describes the three-dimensional flow of both single- and two-phase, single-component water and the transport of heat in porous media. The derivation begins with the point balance equations for mass, momentum, and energy. These equations are then averaged over a finite volume to obtain the macroscopic balance equations for a porous medium. The macroscopic equations are combined by appropriate constitutive relationships to form two similified partial differential equations posed in terms of fluid pressure and enthalpy. A two-dimensional formulation of the simplified equations is also derived by partial integration in the vertical dimension. (Woodard-USGS)

  6. Reaction and internal energy relaxation rates in viscous thermochemically non-equilibrium gas flows

    SciTech Connect

    Kustova, E. V.; Oblapenko, G. P.

    2015-01-15

    In the present paper, reaction and energy relaxation rates as well as the normal stress are studied for viscous gas flows with vibrational and chemical non-equilibrium. Using the modified Chapman-Enskog method, multi-temperature models based on the Treanor and Boltzmann vibrational distributions are developed for the general case taking into account all kinds of vibrational energy transitions, exchange reactions, dissociation, and recombination. Integral equations specifying the first-order corrections to the normal mean stress and reaction rates are derived, as well as approximate systems of linear equations for their numerical computation. Generalized thermodynamic driving forces associated with all non-equilibrium processes are introduced. It is shown that normal stresses and rates of non-equilibrium processes can be expressed in terms of the same driving forces; the symmetry of kinetic coefficients in these expressions is proven. The developed general model is applied to a particular case of a pure N{sub 2} viscous flow with slow VT relaxation. Normal stress and rates of vibrational relaxation are studied for various ratios of vibrational and translational temperatures. The cross effects between different vibrational transitions in viscous flows are evaluated, along with the influence of anharmonicity and flow compressibility on the first-order corrections to the relaxation rate. Limits of validity for the widely used Landau–Teller model of vibrational relaxation are indicated.

  7. Reaction and internal energy relaxation rates in viscous thermochemically non-equilibrium gas flows

    NASA Astrophysics Data System (ADS)

    Kustova, E. V.; Oblapenko, G. P.

    2015-01-01

    In the present paper, reaction and energy relaxation rates as well as the normal stress are studied for viscous gas flows with vibrational and chemical non-equilibrium. Using the modified Chapman-Enskog method, multi-temperature models based on the Treanor and Boltzmann vibrational distributions are developed for the general case taking into account all kinds of vibrational energy transitions, exchange reactions, dissociation, and recombination. Integral equations specifying the first-order corrections to the normal mean stress and reaction rates are derived, as well as approximate systems of linear equations for their numerical computation. Generalized thermodynamic driving forces associated with all non-equilibrium processes are introduced. It is shown that normal stresses and rates of non-equilibrium processes can be expressed in terms of the same driving forces; the symmetry of kinetic coefficients in these expressions is proven. The developed general model is applied to a particular case of a pure N2 viscous flow with slow VT relaxation. Normal stress and rates of vibrational relaxation are studied for various ratios of vibrational and translational temperatures. The cross effects between different vibrational transitions in viscous flows are evaluated, along with the influence of anharmonicity and flow compressibility on the first-order corrections to the relaxation rate. Limits of validity for the widely used Landau-Teller model of vibrational relaxation are indicated.

  8. Properties of the kinetic energy budgets in wall-bounded turbulent flows

    NASA Astrophysics Data System (ADS)

    Zhou, Ang; Klewicki, Joseph

    2016-08-01

    Available high-quality numerical simulation data are used to investigate and characterize the kinetic energy budgets for fully developed turbulent flow in pipes and channels, and in the zero-pressure gradient turbulent boundary layer. The mean kinetic energy equation in these flows is empirically and analytically shown to respectively exhibit the same four-layer leading-order balance structure as the mean momentum equation. This property of the mean kinetic energy budget provides guidance on how to group terms in the more complicated turbulence and total kinetic energy budgets. Under the suggested grouping, the turbulence budget shows either a two- or three-layer structure (depending on channel or pipe versus boundary layer flow), while the total kinetic energy budget exhibits a clear four-layer structure. These layers, however, differ in position and size and exhibit variations with friction Reynolds number (δ+) that are distinct from the layer structure associated with the mean dynamics. The present analyses indicate that each of the four layers is characterized by a predominance of a reduced set of the grouped terms in the governing equation. The width of the third layer is mathematically reasoned to scale like δ+-√{δ+} at finite Reynolds numbers. In the boundary layer the upper bounds of both the second and third layers convincingly merge under this normalization, as does the width of the third layer. This normalization also seems to be valid for the width of the third layer in pipes and channels, but only for δ+>1000 . The leading-order balances in the total kinetic energy budget are shown to arise from a nontrivial interweaving of the mean and turbulence budget contributions with distance from the wall.

  9. Comparing the magnitude of simulated residential rebound effects from electric end-use efficiency across the US

    NASA Astrophysics Data System (ADS)

    Thomas, Brinda A.; Hausfather, Zeke; Azevedo, Inês L.

    2014-07-01

    Many US states rely on energy efficiency goals as a strategy to reduce CO2e emissions and air pollution, to minimize investments in new power plants, and to create jobs. For those energy efficiency interventions that are cost-effective, i.e., saving money and reducing energy, consumers may increase their use of energy services, or re-spend cost savings on other carbon- and energy-intensive goods and services. In this paper, we simulate the magnitude of these ‘rebound effects’ in each of the 50 states in terms of CO2e emissions, focusing on residential electric end-uses under plausible assumptions. We find that a 10% reduction in annual electricity use by a household results in an emissions’ reduction penalty ranging from 0.1 ton CO2e in California to 0.3 ton CO2e in Alabama (from potential emissions reductions of 0.3 ton CO2e and 1.6 ton CO2e, respectively, in the no rebound case). Rebound effects, percentage-wise, range from 6% in West Virginia (which has a high-carbon electricity and low electricity prices), to as high as 40% in California (which has low-carbon electricity and high electricity prices). The magnitude of rebound effects percentage-wise depends on the carbon intensity of the grid: in states with low emissions factors and higher electricity prices, such as California, the rebound effects are much larger percentage-wise than in states like Pennsylvania. Conversely, the states with larger per cent rebound effects are the ones where the implications in terms of absolute emissions changes are the smallest.

  10. A PCM/forced convection conjugate transient analysis of energy storage systems with annular and countercurrent flows

    NASA Technical Reports Server (NTRS)

    Cao, Y.; Faghri, A.; Juhasz, A.

    1991-01-01

    Latent heat energy storage systems with both annular and countercurrent flows are modeled numerically. The change of phase of the phase-change material (PCM) and the transient forced convective heat transfer for the transfer fluid are solved simultaneously as a conjugate problem. A parametric study and a system optimization are conducted. It is found that the energy storage system with the countercurrent flow is an efficient way to absorb heat energy in a short period for pulsed power load space applications.

  11. Nonlinear effects of energy sources and the jet at supersonic flow in the channel

    NASA Astrophysics Data System (ADS)

    Zamuraev, V. P.; Kalinina, A. P.

    2016-10-01

    The work is devoted to the mathematical modeling of the influence of transversal jet and the near-wall energy sources on the shock wave structure of supersonic flow in channel with variable cross section. Stable regimes with the region of transonic velocities are obtained. Their stability is confirmed by the width of the corridor of the input power in the area of the regime existence.

  12. An energy analysis of the stability of flexible filaments in coaxial flow

    NASA Astrophysics Data System (ADS)

    Iadikin, Iu. V.

    1982-12-01

    An energy-balance equation is obtained for flexible filaments of constant and variable lengths oscillating in coaxial flow. It is found that for any boundary conditions, the stability of a filament increases with internal and external damping, and decreases with hydrodynamic drag. It is also shown that tensile and gyroscopic forces applied to the free end of a filament increase the filament stability, whereas the centrifugal force of the associated liquid mass has the opposite effect.

  13. Upscale energy transfer and flow topology in free-surface turbulence.

    PubMed

    Lovecchio, Salvatore; Zonta, Francesco; Soldati, Alfredo

    2015-03-01

    Free-surface turbulence, albeit constrained onto a two-dimensional space, exhibits features that barely resemble predictions of simplified two-dimensional modeling. We demonstrate that, in a three-dimensional open channel flow, surface turbulence is characterized by upscale energy transfer, which controls the long-term evolution of the larger scales. We are able to associate downscale and upscale energy transfer at the surface with the two-dimensional divergence of velocity. We finally demonstrate that surface compressibility confirms the strongly three-dimensional nature of surface turbulence.

  14. Bounded energy states in homogeneous turbulent shear flow - An alternative view

    NASA Technical Reports Server (NTRS)

    Bernard, P. S.; Speziale, C. G.

    1992-01-01

    The equilibrium structure of homogeneous turbulent shear flow is investigated from a theoretical standpoint. Existing turbulence models, in apparent agreement with physical and numerical experiments, predict an unbounded exponential time growth of the turbulent kinetic energy and dissipation rate; only the anisotropy tensor and turbulent time scale reach a structural equilibrium. It is shown that if a residual vortex stretching term is maintained in the dissipation rate transport equation, then there can exist equilibrium solutions, with bounded energy states, where the turbulence production is balanced by its dissipation. Illustrative calculations are presented for a k-epsilon model modified to account for net vortex stretching.

  15. Effect of Surface Energy Pulses on Supersonic Flow in a Channel of Variable Cross Section

    NASA Astrophysics Data System (ADS)

    Zamuraev, V. P.; Kalinina, A. P.

    2016-05-01

    The influence of a surface pulse-periodic supply of energy on the formation of shock-wave structures in a plane channel of variable cross section has been studied. Energy is supplied to the constant cross-section units of the channel with the flow Mach number M = 2. The time-average supplied power corresponds to the combustion of hydrogen with the excess-air coefficient from 1 to 10. The problem is solved within the framework of the Euler equations. A dimensionless approach is used to analyze the effect of sources. The applicability of the analytical relations obtained is confirmed by numerical solution of two-dimensional Euler equations.

  16. A high-energy-density redox flow battery based on zinc/polyhalide chemistry.

    PubMed

    Zhang, Liqun; Lai, Qinzhi; Zhang, Jianlu; Zhang, Huamin

    2012-05-01

    Zn and the Art of Battery Development: A zinc/polyhalide redox flow battery employs Br(-) /ClBr(2-) and Zn/Zn(2+) redox couples in its positive and negative half-cells, respectively. The performance of the battery is evaluated by charge-discharge cycling tests and reveals a high energy efficiency of 81%, based on a Coulombic efficiency of 96% and voltage efficiency of 84%. The new battery technology can provide high performance and energy density at an acceptable cost.

  17. Hybrid piezoelectric-inductive flow energy harvesting and dimensionless electroaeroelastic analysis for scaling

    NASA Astrophysics Data System (ADS)

    Dias, J. A. C.; De Marqui, C.; Erturk, A.

    2013-01-01

    Piezoelectric and electromagnetic transduction techniques have peculiar advantages to leverage in the growing field of flow energy harvesting from aeroelastic vibrations. This letter presents the concept of hybrid piezoelectric-inductive power generation with electroaeroelastic modeling and simulations. Dimensionless analysis of the coupled system dynamics is indispensable to proper geometric scaling and optimization of aeroelastic energy harvesters. The governing electroaeroelastic equations are given in dimensionless form, and the effects of aeroelastic and electrical properties are investigated in detail toward understanding the dependence of the cut-in speed (flutter speed) and the maximum power output of the harvester on the system parameters.

  18. The formation of reverse shocks in magnetized high energy density supersonic plasma flows

    SciTech Connect

    Lebedev, S. V. E-mail: l.suttle10@imperial.ac.uk; Suttle, L.; Swadling, G. F.; Bennett, M.; Bland, S. N.; Burdiak, G. C.; Chittenden, J. P.; Grouchy, P. de; Hall, G. N.; Hare, J. D.; Kalmoni, N.; Niasse, N.; Patankar, S.; Smith, R. A.; Suzuki-Vidal, F.; Burgess, D.; Clemens, A.; Ciardi, A.; Sheng, L.; Yuan, J.; and others

    2014-05-15

    A new experimental platform was developed, based on the use of supersonic plasma flow from the ablation stage of an inverse wire array z-pinch, for studies of shocks in magnetized high energy density physics plasmas in a well-defined and diagnosable 1-D interaction geometry. The mechanism of flow generation ensures that the plasma flow (Re{sub M} ∼ 50, M{sub S} ∼ 5, M{sub A} ∼ 8, V{sub flow} ≈ 100 km/s) has a frozen-in magnetic field at a level sufficient to affect shocks formed by its interaction with obstacles. It is found that in addition to the expected accumulation of stagnated plasma in a thin layer at the surface of a planar obstacle, the presence of the magnetic field leads to the formation of an additional detached density jump in the upstream plasma, at a distance of ∼c/ω{sub pi} from the obstacle. Analysis of the data obtained with Thomson scattering, interferometry, and local magnetic probes suggests that the sub-shock develops due to the pile-up of the magnetic flux advected by the plasma flow.

  19. Active Flow Control Integrated Diffuser for increased Energy Efficiency in Variable Air Volume Systems

    NASA Astrophysics Data System (ADS)

    van der Schijff, Hermanus; Menicovich, David; Vollen, Jason; Amitay, Michael

    2013-11-01

    An experimental investigation was performed to study the application of flow control on an HVAC diffuser using synthetic jets distributed evenly along the diffuser edges. The study was conducted on 1:3 scale typical office space (150 ft2) , which included a simulated scale HVAC system supplied by compressed air. Two different jet momentum coefficients were investigated for two inlet flow rates of 40 and 60 CFM. The flow field was measured using hot wire anemometry and Particle Image Velocimetry. Current Variable Air Volume HVAC systems vary the incoming airflow to adjust to changing temperature conditions in the conditioned space. However, when the air flow rate drops below ideal, air distribution becomes inefficient. This study demonstrates the effectiveness of synthetic jets at controlling the incoming airflow and the distribution in the room, showing ability to affect throw coefficient parameters for different flow rates within the test chamber. The use of such devices has the potential to improve air quality and air distribution in building while simultaneously lowering energy demands of HVAC systems.

  20. Analysis of the dynamic energy flow associated with phagocytosis of bacteria.

    PubMed

    Okpala, Paul; Omenyi, Sam; Ozoegwu, Godwin; Achebe, Chinonso

    2015-09-01

    This paper treats the phenomenon of phagocytosis from the flow of energy point of view. Considerable efforts have been made towards elucidating the subject of phagocytosis in other fields of learning, but little has been said about the mechanical work that is done during phagocytosis. Phagocytosis without doubt is an interaction that involves the flow of energy. Energy equation model of phagocytosis is then presented in this paper to analyze the mechanical energy that is involved in the build-up of the engulfment of bacteria by the phagocytes. Data of the E Coli bacteria from published work was then applied to the solution of the energy equation. A borderline contact angle [Formula: see text] of [Formula: see text] between the phagocyte and the bacteria at [Formula: see text] was deduced in this work. It was shown that when [Formula: see text], [Formula: see text], engulfment is favoured and when [Formula: see text], [Formula: see text], engulfment is not favoured for E-coli. This condition is conceptually in line with ΔFNET approach reported in the literature. Data of four different bacterial species were also used to plot the graphs of the engulfment parameter [Formula: see text] against contact angle [Formula: see text] which revealed that the more hydrophobic bacteria are easily phagocytized than the more hydrophilic ones. PMID:27441215

  1. Harvesting Energy from the Flow-Induced Flutter of a `Piezoleaf'

    NASA Astrophysics Data System (ADS)

    Ruas, Andre; Orrego, Santiago; Doran, Kyle; Rips, Aaron; Shoele, Kourosh; Kang, Sung Hoon; Mittal, Rajat

    The objective of our research is to examine energy harvesting from the flow-induced flutter of a small piezoelectric membrane, which we call a `Piezoleaf'. Piezoleaves are small, low-cost, low-maintenance devices capable of powering small portable electronics or wireless sensors in remote areas. It is well known that piezoelectric membranes subjected to time-varying strains generate electrical energy that can be harvested. In the current project, we have designed and constructed a new, low-speed wind-tunnel (1'x1', cross-section) to analyze the flow-induced flutter and energy harvesting performance of a small (approximately 1''x2'') piezoleaf. One of the novel features of this research is that the membrane is fixed at its trailing-edge (i.e. an inverted flag) since this is expected to generate more energy than a regular flag configuration. Guided by numerical simulation, we are conducting tests of this configuration in our wind tunnel for various wind speeds (maximum speeds of about 10 m/s) to examine the effect of wind-speed on the flutter and energy harvesting. High-speed videography is also being used to examine the dynamics of the flag and results from this project will be presented.

  2. 7 CFR 782.23 - Failure to file end-use certificates or consumption and resale reports.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 7 2011-01-01 2011-01-01 false Failure to file end-use certificates or consumption... Records and Reports § 782.23 Failure to file end-use certificates or consumption and resale reports... Certificate for Wheat, and form FSA-751, Wheat Consumption and Resale Report, as applicable, and retain...

  3. 7 CFR 782.23 - Failure to file end-use certificates or consumption and resale reports.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Failure to file end-use certificates or consumption... Records and Reports § 782.23 Failure to file end-use certificates or consumption and resale reports... Certificate for Wheat, and form FSA-751, Wheat Consumption and Resale Report, as applicable, and retain...

  4. Flow of chemical energy in Alwar jheel of Yamuna basin near Allahabad.

    PubMed

    Kumar, Amit; Watal, Geeta

    2006-07-01

    The water quality, rate of energy transformation, chemical composition of producers and flow of chemical energy were studied in both feeding river Yamuna and Alwar jheel near Allahabad. As the river Yamuna had high value of alkalinity (210.0 mgl(-1)), conductance (518.0 micromhos), dissolved solids (260.0 mgl(-1)), hardness (162.0 mgl(-1)) and chloride (54.6 mgl(-1)) jheel also showed high values of these parameters. The rate of energy transformation from kinetic radiant energy to chemical energy was very high in the jheel 32,315 Cal m(-2) day(-1) of which 25,620 Cal m(-2) day(-1) was contributed by aquatic plants. Out of 11,764 x 10(4) Kcal ha(-1) yr(-1) total energy fixed in the system, producers stored 7,154 x 10(4) Kcal ha(-1) yr(-1) and the rest was lost as heat of respiration. The pattern of storage of energy was different in two groups of producers and thus most of the energy fixed by phytoplankton was stored as protein (56.2%) and less as carbohydrate (11.7%) while aquatic plants stored more energy as carbohydrate (40.8%) than protein (23.2%). The chemical energy obtained from the system was 1,85,000 Kcal ha(-1) yr(-1) and thus only 0.260% of the chemical energy stored by producers was harvested. The potential chemical energy resource in the jheel was 81.4 x 10(4) Kcal ha(-1) yr(-1) of which only 22.6% was harvested in the jheel and there is enough scope for further enhancement. PMID:17402247

  5. Flow of chemical energy in Alwar jheel of Yamuna basin near Allahabad.

    PubMed

    Kumar, Amit; Watal, Geeta

    2006-07-01

    The water quality, rate of energy transformation, chemical composition of producers and flow of chemical energy were studied in both feeding river Yamuna and Alwar jheel near Allahabad. As the river Yamuna had high value of alkalinity (210.0 mgl(-1)), conductance (518.0 micromhos), dissolved solids (260.0 mgl(-1)), hardness (162.0 mgl(-1)) and chloride (54.6 mgl(-1)) jheel also showed high values of these parameters. The rate of energy transformation from kinetic radiant energy to chemical energy was very high in the jheel 32,315 Cal m(-2) day(-1) of which 25,620 Cal m(-2) day(-1) was contributed by aquatic plants. Out of 11,764 x 10(4) Kcal ha(-1) yr(-1) total energy fixed in the system, producers stored 7,154 x 10(4) Kcal ha(-1) yr(-1) and the rest was lost as heat of respiration. The pattern of storage of energy was different in two groups of producers and thus most of the energy fixed by phytoplankton was stored as protein (56.2%) and less as carbohydrate (11.7%) while aquatic plants stored more energy as carbohydrate (40.8%) than protein (23.2%). The chemical energy obtained from the system was 1,85,000 Kcal ha(-1) yr(-1) and thus only 0.260% of the chemical energy stored by producers was harvested. The potential chemical energy resource in the jheel was 81.4 x 10(4) Kcal ha(-1) yr(-1) of which only 22.6% was harvested in the jheel and there is enough scope for further enhancement.

  6. Nanofluid heat transfer under mixed convection flow in a tube for solar thermal energy applications.

    PubMed

    Sekhar, Y Raja; Sharma, K V; Kamal, Subhash

    2016-05-01

    The solar flat plate collector operating under different convective modes has low efficiency for energy conversion. The energy absorbed by the working fluid in the collector system and its heat transfer characteristics vary with solar insolation and mass flow rate. The performance of the system is improved by reducing the losses from the collector. Various passive methods have been devised to aid energy absorption by the working fluid. Also, working fluids are modified using nanoparticles to improve the thermal properties of the fluid. In the present work, simulation and experimental studies are undertaken for pipe flow at constant heat flux boundary condition in the mixed convection mode. The working fluid at low Reynolds number in the mixed laminar flow range is undertaken with water in thermosyphon mode for different inclination angles of the tube. Local and average coefficients are determined experimentally and compared with theoretical values for water-based Al2O3 nanofluids. The results show an enhancement in heat transfer in the experimental range with Rayleigh number at higher inclinations of the collector tube for water and nanofluids.

  7. Energy policy act transportation study: Interim report on natural gas flows and rates

    SciTech Connect

    1995-11-17

    This report, Energy Policy Act Transportation Study: Interim Report on Natural Gas Flows and Rates, is the second in a series mandated by Title XIII, Section 1340, ``Establishment of Data Base and Study of Transportation Rates,`` of the Energy Policy Act of 1992 (P.L. 102--486). The first report Energy Policy Act Transportation Study: Availability of Data and Studies, was submitted to Congress in October 1993; it summarized data and studies that could be used to address the impact of legislative and regulatory actions on natural gas transportation rates and flow patterns. The current report presents an interim analysis of natural gas transportation rates and distribution patterns for the period from 1988 through 1994. A third and final report addressing the transportation rates and flows through 1997 is due to Congress in October 2000. This analysis relies on currently available data; no new data collection effort was undertaken. The need for the collection of additional data on transportation rates will be further addressed after this report, in consultation with the Congress, industry representatives, and in other public forums.

  8. Vibrational energy flow in photoactive yellow protein revealed by infrared pump-visible probe spectroscopy.

    PubMed

    Nakamura, Ryosuke; Hamada, Norio

    2015-05-14

    Vibrational energy flow in the electronic ground state of photoactive yellow protein (PYP) is studied by ultrafast infrared (IR) pump-visible probe spectroscopy. Vibrational modes of the chromophore and the surrounding protein are excited with a femtosecond IR pump pulse, and the subsequent vibrational dynamics in the chromophore are selectively probed with a visible probe pulse through changes in the absorption spectrum of the chromophore. We thus obtain the vibrational energy flow with four characteristic time constants. The vibrational excitation with an IR pulse at 1340, 1420, 1500, or 1670 cm(-1) results in ultrafast intramolecular vibrational redistribution (IVR) with a time constant of 0.2 ps. The vibrational modes excited through the IVR process relax to the initial ground state with a time constant of 6-8 ps in parallel with vibrational cooling with a time constant of 14 ps. In addition, upon excitation with an IR pulse at 1670 cm(-1), we observe the energy flow from the protein backbone to the chromophore that occurs with a time constant of 4.2 ps. PMID:25896223

  9. Nanofluid heat transfer under mixed convection flow in a tube for solar thermal energy applications.

    PubMed

    Sekhar, Y Raja; Sharma, K V; Kamal, Subhash

    2016-05-01

    The solar flat plate collector operating under different convective modes has low efficiency for energy conversion. The energy absorbed by the working fluid in the collector system and its heat transfer characteristics vary with solar insolation and mass flow rate. The performance of the system is improved by reducing the losses from the collector. Various passive methods have been devised to aid energy absorption by the working fluid. Also, working fluids are modified using nanoparticles to improve the thermal properties of the fluid. In the present work, simulation and experimental studies are undertaken for pipe flow at constant heat flux boundary condition in the mixed convection mode. The working fluid at low Reynolds number in the mixed laminar flow range is undertaken with water in thermosyphon mode for different inclination angles of the tube. Local and average coefficients are determined experimentally and compared with theoretical values for water-based Al2O3 nanofluids. The results show an enhancement in heat transfer in the experimental range with Rayleigh number at higher inclinations of the collector tube for water and nanofluids. PMID:26593731

  10. Harvesting Energy from Salinity Differences Using Battery Electrodes in a Concentration Flow Cell.

    PubMed

    Kim, Taeyoung; Rahimi, Mohammad; Logan, Bruce E; Gorski, Christopher A

    2016-09-01

    Salinity-gradient energy (SGE) technologies produce carbon-neutral and renewable electricity from salinity differences between seawater and freshwater. Capacitive mixing (CapMix) is a promising class of SGE technologies that captures energy using capacitive or battery electrodes, but CapMix devices have produced relatively low power densities and often require expensive materials. Here, we combined existing CapMix approaches to develop a concentration flow cell that can overcome these limitations. In this system, two identical battery (i.e., faradaic) electrodes composed of copper hexacyanoferrate (CuHCF) were simultaneously exposed to either high (0.513 M) or low (0.017 M) concentration NaCl solutions in channels separated by a filtration membrane. The average power density produced was 411 ± 14 mW m(-2) (normalized to membrane area), which was twice as high as previously reported values for CapMix devices. Power production was continuous (i.e., it did not require a charging period and did not vary during each step of a cycle) and was stable for 20 cycles of switching the solutions in each channel. The concentration flow cell only used inexpensive materials and did not require ion-selective membranes or precious metals. The results demonstrate that the concentration flow cell is a promising approach for efficiently harvesting energy from salinity differences. PMID:27518198

  11. Harvesting Energy from Salinity Differences Using Battery Electrodes in a Concentration Flow Cell.

    PubMed

    Kim, Taeyoung; Rahimi, Mohammad; Logan, Bruce E; Gorski, Christopher A

    2016-09-01

    Salinity-gradient energy (SGE) technologies produce carbon-neutral and renewable electricity from salinity differences between seawater and freshwater. Capacitive mixing (CapMix) is a promising class of SGE technologies that captures energy using capacitive or battery electrodes, but CapMix devices have produced relatively low power densities and often require expensive materials. Here, we combined existing CapMix approaches to develop a concentration flow cell that can overcome these limitations. In this system, two identical battery (i.e., faradaic) electrodes composed of copper hexacyanoferrate (CuHCF) were simultaneously exposed to either high (0.513 M) or low (0.017 M) concentration NaCl solutions in channels separated by a filtration membrane. The average power density produced was 411 ± 14 mW m(-2) (normalized to membrane area), which was twice as high as previously reported values for CapMix devices. Power production was continuous (i.e., it did not require a charging period and did not vary during each step of a cycle) and was stable for 20 cycles of switching the solutions in each channel. The concentration flow cell only used inexpensive materials and did not require ion-selective membranes or precious metals. The results demonstrate that the concentration flow cell is a promising approach for efficiently harvesting energy from salinity differences.

  12. DEVELOPMENT OF A LOW-COST INFERENTIAL NATURAL GAS ENERGY FLOW RATE PROTOTYPE RETROFIT MODULE

    SciTech Connect

    E. Kelner; T.E. Owen; D.L. George; A. Minachi; M.G. Nored; C.J. Schwartz

    2004-03-01

    In 1998, Southwest Research Institute{reg_sign} began a multi-year project co-funded by the Gas Research Institute (GRI) and the U.S. Department of Energy. The project goal is to develop a working prototype instrument module for natural gas energy measurement. The module will be used to retrofit a natural gas custody transfer flow meter for energy measurement, at a cost an order of magnitude lower than a gas chromatograph. Development and evaluation of the prototype retrofit natural gas energy flow meter in 2000-2001 included: (1) evaluation of the inferential gas energy analysis algorithm using supplemental gas databases and anticipated worst-case gas mixtures; (2) identification and feasibility review of potential sensing technologies for nitrogen diluent content; (3) experimental performance evaluation of infrared absorption sensors for carbon dioxide diluent content; and (4) procurement of a custom ultrasonic transducer and redesign of the ultrasonic pulse reflection correlation sensor for precision speed-of-sound measurements. A prototype energy meter module containing improved carbon dioxide and speed-of-sound sensors was constructed and tested in the GRI Metering Research Facility at SwRI. Performance of this module using transmission-quality natural gas and gas containing supplemental carbon dioxide up to 9 mol% resulted in gas energy determinations well within the inferential algorithm worst-case tolerance of {+-}2.4 Btu/scf (nitrogen diluent gas measured by gas chromatograph). A two-week field test was performed at a gas-fired power plant to evaluate the inferential algorithm and the data acquisition requirements needed to adapt the prototype energy meter module to practical field site conditions.

  13. Resource Evaluation and Energy Production Estimate for a Tidal Energy Conversion Installation using Acoustic Flow Measurements

    NASA Astrophysics Data System (ADS)

    Gagnon, Ian; Baldwin, Ken; Wosnik, Martin

    2015-11-01

    The ``Living Bridge'' project plans to install a tidal turbine at Memorial Bridge in the Piscataqua River at Portsmouth, NH. A spatio-temporal tidal energy resource assessment was performed using long term bottom-deployed Acoustic Doppler Current Profilers ADCP. Two locations were evaluated: at the planned deployment location and mid-channel. The goal was to determine the amount of available kinetic energy that can be converted into usable electrical energy on the bridge. Changes in available kinetic energy with ebb/flood and spring/neap tidal cycles and electrical energy demand were analyzed. A system model is used to calculate the net energy savings using various tidal generator and battery bank configurations. Differences in the tidal characteristics between the two measurement locations are highlighted. Different resource evaluation methodologies were also analyzed, e.g., using a representative ADCP ``bin'' vs. a more refined, turbine-geometry-specific methodology, and using static bin height vs. bin height that move w.r.t. the free surface throughout a tidal cycle (representative of a bottom-fixed or floating turbine deployment, respectively). ADCP operating frequencies and bin sizes affect the standard deviation of measurements, and measurement uncertainties are evaluated. Supported by NSF-IIP grant 1430260.

  14. Flow at Brookhaven AGS Energy (11.6 GeV/nucleon): A barometer for high density effects?

    SciTech Connect

    Kahana, D.E.; Shuryak, E.; Pang, Y.; Pang, Y.

    1997-07-01

    Preliminary data on transverse energy {open_quotes}flow{close_quotes} and event asymmetries reported by the E877(814) Collaborations are compared to ARC (a relativistic cascade) model calculations for Au+Au at full AGS Brookhaven (Alternating Gradient Synchroton) beam energy. ARC triple differential cross sections for protons and pions are presented. Proton flow is produced in ARC, with the maximum {l_angle}P{sub x}{r_angle}{approximately}120 MeV/c. For central events {l_angle}P{sub x}{r_angle} for the pions is near zero, consistent with experiment. The comparison with data provides a constraint on the size of flow at the highest energy available, to be put beside that at Bevalac energy. This sets the stage for examining flow at intermediate energies, now being measured by E895, for signs of baryon rich plasma. {copyright} {ital 1997} {ital The American Physical Society}

  15. 1980 survey and evaluation of utility conservation, load management, and solar end-use projects. Volume 3: utility load management projects. Final report

    SciTech Connect

    Not Available

    1982-01-01

    The results of the 1980 survey of electric utility-sponsored energy conservation, load management, and end-use solar energy conversion projects are described. The work is an expansion of a previous survey and evaluation and has been jointly sponsored by EPRI and DOE through the Oak Ridge National Laboratory. There are three volumes and a summary document. Each volume presents the results of an extensive survey to determine electric utility involvement in customer-side projects related to the particular technology (i.e., conservation, solar, or load management), selected descriptions of utility projects and results, and first-level technical and economic evaluations.

  16. Reaction mechanism and reaction coordinates from the viewpoint of energy flow.

    PubMed

    Li, Wenjin; Ma, Ao

    2016-03-21

    Reaction coordinates are of central importance for correct understanding of reaction dynamics in complex systems, but their counter-intuitive nature made it a daunting challenge to identify them. Starting from an energetic view of a reaction process as stochastic energy flows biased towards preferred channels, which we deemed the reaction coordinates, we developed a rigorous scheme for decomposing energy changes of a system, both potential and kinetic, into pairwise components. The pairwise energy flows between different coordinates provide a concrete statistical mechanical language for depicting reaction mechanisms. Application of this scheme to the C7eq → C7ax transition of the alanine dipeptide in vacuum revealed novel and intriguing mechanisms that eluded previous investigations of this well studied prototype system for biomolecular conformational dynamics. Using a cost function developed from the energy decomposition components by proper averaging over the transition path ensemble, we were able to identify signatures of the reaction coordinates of this system without requiring any input from human intuition.

  17. Influences of trunk flexion on mechanical energy flow in the lower extremities during gait

    PubMed Central

    Takeda, Takuya; Anan, Masaya; Takahashi, Makoto; Ogata, Yuta; Tanimoto, Kenji; Shinkoda, Koichi

    2016-01-01

    [Purpose] The time-series waveforms of mechanical energy generation, absorption, and transfer through the joints indicate how movements are produced and controlled. Previous studies have used these waveforms to evaluate and describe the efficiency of human movements. The purpose of this study was to examine the influence of trunk flexion on mechanical energy flow in the lower extremities during gait. [Subjects and Methods] The subjects were 8 healthy young males (mean age, 21.8 ± 1.3 years, mean height, 170.5 ± 6.8 cm, and mean weight, 60.2 ± 6.8 kg). Subjects walked at a self-selected gait speed under 2 conditions: normal gait (condition N), and gait with trunk flexion formed with a brace to simulate spinal curvature (condition TF). The data collected from initial contact to the mid-stance of gait was analyzed. [Results] There were no significant differences between the 2 conditions in the mechanical energy flow in the knee joint and negative mechanical work in the knee joint. However, the positive mechanical work of the knee joint under condition TF was significantly less than that under condition N. [Conclusion] Trunk flexion led to knee flexion in a standing posture. Thus, a strategy of moving of center of mass upward by knee extension using less mechanical energy was selected during gait in the trunk flexed posture. PMID:27313351

  18. Management of old landfills by utilizing forest and energy industry waste flows.

    PubMed

    Niutanen, Ville; Korhonen, Jouni

    2002-05-01

    The lack of landfill capacity, forthcoming EU waste disposal and landfill management legislation and the use of non-renewable and energy intensive natural resources for the end-treatment of old landfills increase pressures to develop new landfill management methods. This paper considers a method for the end-management of old landfills in Finland, which is based on the utilization of forest and paper industry waste flows, wastes from paper recycling (de-inking) and wastes from forest industry energy production. Fibre clay wastes from paper mills, de-inking sludges from de-inking of recovered waste paper and incineration ash from forest industry power plants serve to substitute the use of natural clay for the building of landfill structures for closed landfills. Arguably, this method is preferable to existing practices of natural clay use for landfill building, because it (1) substitutes non-renewable natural clay, (2) consumes less energy and generates less CO2 emissions than the use of natural clay, and (3) eliminates considerable amounts of wastes from paper production, paper consumption and from forest industry energy production. Some difficulties in the application of the method are considered and the waste flow utilization is incorporated into a local forest industry recycling network. PMID:12173421

  19. Influences of trunk flexion on mechanical energy flow in the lower extremities during gait.

    PubMed

    Takeda, Takuya; Anan, Masaya; Takahashi, Makoto; Ogata, Yuta; Tanimoto, Kenji; Shinkoda, Koichi

    2016-05-01

    [Purpose] The time-series waveforms of mechanical energy generation, absorption, and transfer through the joints indicate how movements are produced and controlled. Previous studies have used these waveforms to evaluate and describe the efficiency of human movements. The purpose of this study was to examine the influence of trunk flexion on mechanical energy flow in the lower extremities during gait. [Subjects and Methods] The subjects were 8 healthy young males (mean age, 21.8 ± 1.3 years, mean height, 170.5 ± 6.8 cm, and mean weight, 60.2 ± 6.8 kg). Subjects walked at a self-selected gait speed under 2 conditions: normal gait (condition N), and gait with trunk flexion formed with a brace to simulate spinal curvature (condition TF). The data collected from initial contact to the mid-stance of gait was analyzed. [Results] There were no significant differences between the 2 conditions in the mechanical energy flow in the knee joint and negative mechanical work in the knee joint. However, the positive mechanical work of the knee joint under condition TF was significantly less than that under condition N. [Conclusion] Trunk flexion led to knee flexion in a standing posture. Thus, a strategy of moving of center of mass upward by knee extension using less mechanical energy was selected during gait in the trunk flexed posture.

  20. Quality evaluation of energy consumed in flow regulation method by speed variation in centrifugal pumps

    NASA Astrophysics Data System (ADS)

    Morales, S.; Culman, M.; Acevedo, C.; Rey, C.

    2014-06-01

    Nowadays, energy efficiency and the Electric Power Quality are two inseparable issues in the evaluation of three-phase induction motors, framed within the program of Rational and Efficient Use of Energy (RUE).The use of efficient energy saving devices has been increasing significantly in RUE programs, for example the use of variable frequency drives (VFD) in pumping systems.The overall objective of the project was to evaluate the impact on power quality and energy efficiency in a centrifugal pump driven by an induction three-phase motor, using the flow control method of speed variation by VFD. The fundamental purpose was to test the opinions continuously heard about the use of flow control methods in centrifugal pumps, analyzing the advantages and disadvantages that have been formulated deliberately in order to offer support to the industry in taking correct decisions. The VFD changes the speed of the motor-pump system increasing efficiency compared to the classical methods of regulation. However, the VFD originates conditions that degrade the quality of the electric power supplied to the system and therefore its efficiency, due to the nonlinearity and presence of harmonic currents. It was possible to analyze the power quality, ensuring that the information that comes to the industry is generally biased.

  1. A low-cost iron-cadmium redox flow battery for large-scale energy storage

    NASA Astrophysics Data System (ADS)

    Zeng, Y. K.; Zhao, T. S.; Zhou, X. L.; Wei, L.; Jiang, H. R.

    2016-10-01

    The redox flow battery (RFB) is one of the most promising large-scale energy storage technologies that offer a potential solution to the intermittency of renewable sources such as wind and solar. The prerequisite for widespread utilization of RFBs is low capital cost. In this work, an iron-cadmium redox flow battery (Fe/Cd RFB) with a premixed iron and cadmium solution is developed and tested. It is demonstrated that the coulombic efficiency and energy efficiency of the Fe/Cd RFB reach 98.7% and 80.2% at 120 mA cm-2, respectively. The Fe/Cd RFB exhibits stable efficiencies with capacity retention of 99.87% per cycle during the cycle test. Moreover, the Fe/Cd RFB is estimated to have a low capital cost of 108 kWh-1 for 8-h energy storage. Intrinsically low-cost active materials, high cell performance and excellent capacity retention equip the Fe/Cd RFB to be a promising solution for large-scale energy storage systems.

  2. Management of old landfills by utilizing forest and energy industry waste flows.

    PubMed

    Niutanen, Ville; Korhonen, Jouni

    2002-05-01

    The lack of landfill capacity, forthcoming EU waste disposal and landfill management legislation and the use of non-renewable and energy intensive natural resources for the end-treatment of old landfills increase pressures to develop new landfill management methods. This paper considers a method for the end-management of old landfills in Finland, which is based on the utilization of forest and paper industry waste flows, wastes from paper recycling (de-inking) and wastes from forest industry energy production. Fibre clay wastes from paper mills, de-inking sludges from de-inking of recovered waste paper and incineration ash from forest industry power plants serve to substitute the use of natural clay for the building of landfill structures for closed landfills. Arguably, this method is preferable to existing practices of natural clay use for landfill building, because it (1) substitutes non-renewable natural clay, (2) consumes less energy and generates less CO2 emissions than the use of natural clay, and (3) eliminates considerable amounts of wastes from paper production, paper consumption and from forest industry energy production. Some difficulties in the application of the method are considered and the waste flow utilization is incorporated into a local forest industry recycling network.

  3. Reaction mechanism and reaction coordinates from the viewpoint of energy flow

    NASA Astrophysics Data System (ADS)

    Li, Wenjin; Ma, Ao

    2016-03-01

    Reaction coordinates are of central importance for correct understanding of reaction dynamics in complex systems, but their counter-intuitive nature made it a daunting challenge to identify them. Starting from an energetic view of a reaction process as stochastic energy flows biased towards preferred channels, which we deemed the reaction coordinates, we developed a rigorous scheme for decomposing energy changes of a system, both potential and kinetic, into pairwise components. The pairwise energy flows between different coordinates provide a concrete statistical mechanical language for depicting reaction mechanisms. Application of this scheme to the C7eq → C7ax transition of the alanine dipeptide in vacuum revealed novel and intriguing mechanisms that eluded previous investigations of this well studied prototype system for biomolecular conformational dynamics. Using a cost function developed from the energy decomposition components by proper averaging over the transition path ensemble, we were able to identify signatures of the reaction coordinates of this system without requiring any input from human intuition.

  4. Impact of Groundwater Flow on Thermal Energy Storage and Borehole Thermal Interference

    NASA Astrophysics Data System (ADS)

    Emad Dehkordi, S.; Schincariol, Robert A.

    2013-04-01

    Borehole heat exchanger (BHE) systems are drawing increasing attention and popularity due to their potential energy efficiency and environmental sustainability, as well as their worldwide applicability. Consequently the concern for sustainable designs and proper implementation is rising too. Furthermore an improperly planned and executed system can be economically unjustifiable. To address these issues related design software and to some extent regulatory guidelines have been developed. Thermal input load function and interaction with the subsurface significantly affect thermal performance and sustainability of geothermal heat pump (GHP) systems. Of particular interest is the interaction of such systems with groundwater flow and its impacts. However the related guidelines and the design software do not seem to properly address this growing concern. Typically regulations do not distinguish between high and no groundwater flow conditions, nor do they specify a groundwater velocity threshold at which it becomes important. A further limitation is that most BHE design software used by industry assume a closed box approach discounting the heat transport in/out by the groundwater flow. To efficiently model grids of multiple BHEs, FEFLOW® 6 and the integrated BHE solution is used. Single and multiple borehole grids with U-tube heat exchanger are modeled and compared here. All boreholes are assigned equal heat extraction and flow rates; loop temperatures are then calculated over the system lifetime to compare the thermal efficiency and evaluate the thermal interference between boreholes. For the purpose of assessing the effect of groundwater flow on thermal storage as well as interference, multiple heat loads (balanced and unbalanced) are simulated. Groundwater velocity and borehole spacing are also varied to identify possible thresholds for each case. The study confirms the significance of groundwater flow in certain conditions. The results can be applied to improve the

  5. Internal energy flows of coma-affected singular beams in low-numerical-aperture systems.

    PubMed

    Bahl, Monika; Singh, Brijesh Kumar; Singh, Rakesh Kumar; Senthilkumaran, P

    2015-04-01

    The circulating phase gradient component of a singular beam gets modified when focused by a low-numerical-aperature system suffering from coma aberration. The gradient due to this coma aberration splits the higher charge vortex into elementary vortices and distributes them spatially. This splitting depends on the charge and polarity of the incident singular beam as well as the sign and magnitude of the aberration coefficient. The transverse component of the Poynting vector field distribution at the focal plane is decomposed into the curl or solenoidal component and divergence or irrotational component using the Helmholtz-Hodge decomposition technique. The solenoidal component that relates to the orbital angular momentum carries the circulating energy, while the irrotational component shows the sources and sinks of the energy. Intriguing results of the study of energy flow around the edge dislocations apart from the point phase defects in the irrotational components are also presented.

  6. Modeling of energy transfer between two crossing smoothed laser beams in a plasma with flow profile

    NASA Astrophysics Data System (ADS)

    Colaitis, A.; Hüller, S.; Tikhonchuk, V. T.; Pesme, D.; Duchateau, G.; Porzio, A.

    2016-05-01

    We study the crossed beam energy transfer (CBET) between laser fields generated by optical smoothing methods. The energy transfer, as well as the angular distribution of the outgoing light fields are investigated for two incident smoothed laser beams in a plasma with a flow gradient, allowing for resonant transfer close to the sonic point. Simulations with the code HARMONY based on time-dependent paraxial light propagation are compared to simulations using a new approach based on paraxial complex geometrical optics (PCGO). Both approaches show good agreement for the average energy transfer past a short transient period, which is a promising result for the use of the PCGO method as a module within a hydrodynamics code to efficiently compute CBET in mm-scale plasma configurations. Statistical aspects related to role of laser speckles in CBET are considered via an ensemble of different phase plate realizations.

  7. How rapidly oscillating collapsible tubes extract energy from a viscous mean flow

    NASA Astrophysics Data System (ADS)

    Heil, Matthias; Waters, Sarah L.

    We present a combined theoretical and computational analysis of three-dimensional unsteady finite-Reynolds-number flows in collapsible tubes whose walls perform prescribed high-frequency oscillations which resemble those typically observed in experiments with a Starling resistor. Following an analysis of the flow fields, we investigate the system's overall energy budget and establish the critical Reynolds number, Recrit, at which the wall begins to extract energy from the flow. We conjecture that Recrit corresponds to the Reynolds number beyond which collapsible tubes are capable of performing sustained self-excited oscillations. Our computations suggest a simple functional relationship between Recrit and the system parameters, and we present a scaling argument to explain this observation. Finally, we demonstrate that, within the framework of the instability mechanism analysed here, self-excited oscillations of collapsible tubes are much more likely to develop from steady-state configurations in which the tube is buckled non-axisymmetrically, rather than from axisymmetric steady states, which is in agreement with experimental observations.

  8. Elasto-Aerodynamics-Driven Triboelectric Nanogenerator for Scavenging Air-Flow Energy.

    PubMed

    Wang, Shuhua; Mu, Xiaojing; Wang, Xue; Gu, Alex Yuandong; Wang, Zhong Lin; Yang, Ya

    2015-10-27

    Efficient scavenging the kinetic energy from air-flow represents a promising approach for obtaining clean, sustainable electricity. Here, we report an elasto-aerodynamics-driven triboelectric nanogenerator (TENG) based on contact electrification. The reported TENG consists of a Kapton film with two Cu electrodes at each side, fixed on two ends in an acrylic fluid channel. The relationship between the TENG output power density and its fluid channel dimensions is systematically studied. TENG with a fluid channel size of 125 × 10 × 1.6 mm(3) delivers the maximum output power density of about 9 kW/m(3) under a loading resistance of 2.3 MΩ. Aero-elastic flutter effect explains the air-flow induced vibration of Kapton film well. The output power scales nearly linearly with parallel wiring of multiple TENGs. Connecting 10 TENGs in parallel gives an output power of 25 mW, which allows direct powering of a globe light. The TENG is also utilized to scavenge human breath induced air-flow energy to sustainably power a human body temperature sensor. PMID:26343789

  9. A broadband bi-stable flow energy harvester based on the wake-galloping phenomenon

    NASA Astrophysics Data System (ADS)

    Alhadidi, A. H.; Daqaq, M. F.

    2016-07-01

    Linear wake-galloping flow energy harvesters have a narrow frequency bandwidth restricted to the lock-in region, where the vortex shedding frequency is close to the natural frequency of the harvester. As a result, their performance is very sensitive to variations in the flow speed around the nominal design value. This letter demonstrates that the lock-in region of a wake-galloping flow energy harvester can be improved by exploiting a bi-stable restoring force. To demonstrate the enhanced performance, the response behavior of a bi-stable piezoelectric cantilever harvester is evaluated in a wind tunnel. A Von Kármán vortex street is generated by placing a rectangular rod in the windward direction of the harvester and the voltage response of the harvester is evaluated as a function of the wind speed. It is shown that, compared to the linear design, bi-stability can be used to improve the steady-state bandwidth considerably.

  10. Hybridized electromagnetic-triboelectric nanogenerator for scavenging air-flow energy to sustainably power temperature sensors.

    PubMed

    Wang, Xue; Wang, Shuhua; Yang, Ya; Wang, Zhong Lin

    2015-04-28

    We report a hybridized nanogenerator with dimensions of 6.7 cm × 4.5 cm × 2 cm and a weight of 42.3 g that consists of two triboelectric nanogenerators (TENGs) and two electromagnetic generators (EMGs) for scavenging air-flow energy. Under an air-flow speed of about 18 m/s, the hybridized nanogenerator can deliver largest output powers of 3.5 mW for one TENG (in correspondence of power per unit mass/volume: 8.8 mW/g and 14.6 kW/m(3)) at a loading resistance of 3 MΩ and 1.8 mW for one EMG (in correspondence of power per unit mass/volume: 0.3 mW/g and 0.4 kW/m(3)) at a loading resistance of 2 kΩ, respectively. The hybridized nanogenerator can be utilized to charge a capacitor of 3300 μF to sustainably power four temperature sensors for realizing self-powered temperature sensor networks. Moreover, a wireless temperature sensor driven by a hybridized nanogenerator charged Li-ion battery can work well to send the temperature data to a receiver/computer at a distance of 1.5 m. This work takes a significant step toward air-flow energy harvesting and its potential applications in self-powered wireless sensor networks.

  11. Nitrogen-doped mesoporous carbon for energy storage in vanadium redox flow batteries

    NASA Astrophysics Data System (ADS)

    Shao, Yuyan; Wang, Xiqing; Engelhard, Mark; Wang, Chongmin; Dai, Sheng; Liu, Jun; Yang, Zhenguo; Lin, Yuehe

    We demonstrate an excellent performance of nitrogen-doped mesoporous carbon (N-MPC) for energy storage in vanadium redox flow batteries. Mesoporous carbon (MPC) is prepared using a soft-template method and doped with nitrogen by heat-treating MPC in NH 3. N-MPC is characterized with X-ray photoelectron spectroscopy and transmission electron microscopy. The redox reaction of [VO] 2+/[VO 2] + is characterized with cyclic voltammetry and electrochemical impedance spectroscopy. The electrocatalytic kinetics of the redox couple [VO] 2+/[VO 2] + is significantly enhanced on N-MPC electrode compared with MPC and graphite electrodes. The reversibility of the redox couple [VO] 2+/[VO 2] + is greatly improved on N-MPC (0.61 for N-MPC vs. 0.34 for graphite), which is expected to increase the energy storage efficiency of redox flow batteries. Nitrogen doping facilitates the electron transfer on electrode/electrolyte interface for both oxidation and reduction processes. N-MPC is a promising material for redox flow batteries. This also opens up new and wider applications of nitrogen-doped carbon.

  12. Comparison of spatio-temporal resolution of different flow measurement techniques for marine renewable energy applications

    NASA Astrophysics Data System (ADS)

    Lyon, Vincent; Wosnik, Martin

    2013-11-01

    Marine hydrokinetic (MHK) energy conversion devices are subject to a wide range of turbulent scales, either due to upstream bathymetry, obstacles and waves, or from wakes of upstream devices in array configurations. The commonly used, robust Acoustic Doppler Current Profilers (ADCP) are well suited for long term flow measurements in the marine environment, but are limited to low sampling rates due to their operational principle. The resulting temporal and spatial resolution is insufficient to measure all turbulence scales of interest to the device, e.g., ``blade-scale turbulence.'' The present study systematically characterizes the spatial and temporal resolution of ADCP, Acoustic Doppler Velocimetry (ADV), and Particle Image Velocimetry (PIV). Measurements were conducted in a large cross section tow tank (3.7m × 2.4m) for several benchmark cases, including low and high turbulence intensity uniform flow as well as in the wake of a cylinder, to quantitatively investigate the flow scales which each of the instruments can resolve. The purpose of the study is to supply data for mathematical modeling to improve predictions from ADCP measurements, which can help lead to higher-fidelity energy resource assessment and more accurate device evaluation, including wake measurements. Supported by NSF-CBET grant 1150797.

  13. Elasto-Aerodynamics-Driven Triboelectric Nanogenerator for Scavenging Air-Flow Energy.

    PubMed

    Wang, Shuhua; Mu, Xiaojing; Wang, Xue; Gu, Alex Yuandong; Wang, Zhong Lin; Yang, Ya

    2015-10-27

    Efficient scavenging the kinetic energy from air-flow represents a promising approach for obtaining clean, sustainable electricity. Here, we report an elasto-aerodynamics-driven triboelectric nanogenerator (TENG) based on contact electrification. The reported TENG consists of a Kapton film with two Cu electrodes at each side, fixed on two ends in an acrylic fluid channel. The relationship between the TENG output power density and its fluid channel dimensions is systematically studied. TENG with a fluid channel size of 125 × 10 × 1.6 mm(3) delivers the maximum output power density of about 9 kW/m(3) under a loading resistance of 2.3 MΩ. Aero-elastic flutter effect explains the air-flow induced vibration of Kapton film well. The output power scales nearly linearly with parallel wiring of multiple TENGs. Connecting 10 TENGs in parallel gives an output power of 25 mW, which allows direct powering of a globe light. The TENG is also utilized to scavenge human breath induced air-flow energy to sustainably power a human body temperature sensor.

  14. Dark energy in six nearby galaxy flows: Synthetic phase diagrams and self-similarity

    NASA Astrophysics Data System (ADS)

    Chernin, A. D.; Teerikorpi, P.; Dolgachev, V. P.; Kanter, A. A.; Domozhilova, L. M.; Valtonen, M. J.; Byrd, G. G.

    2012-09-01

    Outward flows of galaxies are observed around groups of galaxies on spatial scales of about 1 Mpc, and around galaxy clusters on scales of 10 Mpc. Using recent data from the Hubble Space Telescope (HST), we have constructed two synthetic velocity-distance phase diagrams: one for four flows on galaxy-group scales and the other for two flows on cluster scales. It has been shown that, in both cases, the antigravity produced by the cosmic dark-energy background is stronger than the gravity produced by the matter in the outflow volume. The antigravity accelerates the flows and introduces a phase attractor that is common to all scales, corresponding to a linear velocity-distance relation (the local Hubble law). As a result, the bundle of outflow trajectories mostly follow the trajectory of the attractor. A comparison of the two diagrams reveals the universal self-similar nature of the outflows: their gross phase structure in dimensionless variables is essentially independent of their physical spatial scales, which differ by approximately a factor of 10 in the two diagrams.

  15. Self-Excited Energy Harvesting in Uniform Fluid Flows Using Piezoelectric Generators

    NASA Astrophysics Data System (ADS)

    Akaydin, Dogus; Elvin, Niell; Andreopoulos, Yiannis

    2010-11-01

    A novel energy harvesting configuration consisting of a circular cylinder attached to a piezoelectric beam is investigated experimentally in this study. The cylinder is attached to the free end of a cantilever beam and undergoes bending deformation due to vortex shedding under uniform fluid flow. The periodic change of strain along the piezoelectric beam generates an alternating voltage that can be used to power an electrical circuit such as a wireless sensor. Two major governing parameters were studied: First, the ratio of the length of the cylinder to its diameter and second, the ratio of the length of the beam to the diameter of the cylinder. Both parameters alter the forcing frequency and magnitude of the flow, natural frequency of the structure and ultimately determine the magnitude of the resultant vibrations. The configuration is different from those previously studies since it is a combination of an oscillating cylinder with a flexible splitter plate and the vibrations are induced within a steady, uniform flow. Three dimensionality of the flow complicates its structure and nonlinear oscillations and lock-in phenomena were observed in experiments with beams of low stiffness. It was also observed that aerodynamic interference with several components of the harvester can significantly alter the harvested power.

  16. Water flow and energy balance for a tropical dry semideciduous forest

    NASA Astrophysics Data System (ADS)

    Andrade, J. L.; Garruña-Hernandez, R.; Leon-Palomo, M.; Us-Santamaria, R.; Sima, J. L.

    2013-05-01

    Tropical forests cool down locally because increase water evaporation from the soil to the atmosphere, reduce albedo and help forming clouds that reflect solar radiation back to the atmosphere; this, aligned to the carbon catchment, increase forests value. We will present an estimation of the sap flow and energy balance for the tropical dry semideciduous forest at Kiuic, Yucatan, Mexico during a year. We use a meteorological tower equipped with a rain gauge, temperature and relative humidity, heat flow plates, thermocouples and volumetric soil water content. We recorded net radiation and soil heat flux and estimated sensible heat and latent heat. Besides, we estimated latent heat by measuring sap flow directly in tres using disispation constant heat probes during the rainy season. Results show the influence of the seasonality on net radiation, air temperatura and vapor pressure deficit, because during the dry season his variables were higher and with more duation than during the rainy and early dry season. Sap flow was different for trees belonging to the family Fabaceae compared to trees from other families.

  17. High Performance Hydrogen/Bromine Redox Flow Battery for Grid-Scale Energy Storage

    SciTech Connect

    Cho, KT; Ridgway, P; Weber, AZ; Haussener, S; Battaglia, V; Srinivasan, V

    2012-01-01

    The electrochemical behavior of a promising hydrogen/bromine redox flow battery is investigated for grid-scale energy-storage application with some of the best redox-flow-battery performance results to date, including a peak power of 1.4 W/cm(2) and a 91% voltaic efficiency at 0.4 W/cm(2) constant-power operation. The kinetics of bromine on various materials is discussed, with both rotating-disk-electrode and cell studies demonstrating that a carbon porous electrode for the bromine reaction can conduct platinum-comparable performance as long as sufficient surface area is realized. The effect of flow-cell designs and operating temperature is examined, and ohmic and mass-transfer losses are decreased by utilizing a flow-through electrode design and increasing cell temperature. Charge/discharge and discharge-rate tests also reveal that this system has highly reversible behavior and good rate capability. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.018211jes] All rights reserved.

  18. Dynamo dominated accretion and energy flow: The mechanism of active galactic nuclei

    SciTech Connect

    Colgate, S.A.; Li, H.

    1998-12-31

    An explanation of the magnetic fields of the universe, the central mass concentration of galaxies, the massive black hole of every galaxy, and the AGN phenomena has been an elusive goal. The authors suggest here the outlines of such a theoretical understanding and point out where the physical understanding is missing. They believe there is an imperative to the sequence of mass flow and hence energy flow in the collapse of a galactic mass starting from the first non-linearity appearing in structure formation following decoupling. This first non-linearity of a two to one density fluctuation, the Lyman-{alpha} clouds, ultimately leads to the emission spectra of the phenomenon of AGN, quasars, blazars, etc. The over-arching physical principle is the various mechanisms for the transport of angular momentum. They believe they have now understood the new physics of two of these mechanisms that have previously been illusive and as a consequence they impose strong constraints on the initial conditions of the mechanisms for the subsequent emission of the gravitational binding energy. The new phenomena described are: (1) the Rossby vortex mechanism of the accretion disk {alpha}-viscosity, and (2) the mechanism of the {alpha}-{Omega} dynamo in the accretion disk. The Rossby vortex mechanism leads to a prediction of the black hole mass and rate of energy release and the {alpha}-{Omega} dynamo leads to the generation of the magnetic flux of the galaxy (and the far greater magnetic flux of clusters) and separately explains the primary flux of energy emission as force-free magnetic energy density. This magnetic flux and magnetic energy density separately are the necessary consequence of the saturation of a dynamo created by the accretion disk with a gain greater than unity.

  19. Flow-Log Analysis for Hydraulic Characterization of Selected Test Wells at the Indian Point Energy Center, Buchanan, New York

    USGS Publications Warehouse

    Williams, John H.

    2008-01-01

    Flow logs from 24 test wells were analyzed as part of the hydraulic characterization of the metamorphosed and fractured carbonate bedrock at the Indian Point Energy Center in Buchanan, New York. The flow logs were analyzed along with caliper, optical- and acoustic-televiewer, and fluid-resistivity and temperature logs to determine the character and distribution of fracture-flow zones and estimate their transmissivities and hydraulic heads. Many flow zones were associated with subhorizontal to shallow-dipping fractured zones, southeast-dipping bedding fractures, northwest-dipping conjugate fractures, or combinations of bedding and conjugate fractures. Flow-log analysis generally provided reasonable first-order estimates of flow-zone transmissivity and head differences compared with the results of conventional hydraulic-test analysis and measurements. Selected results of an aquifer test and a tracer test provided corroborating information in support of the flow-log analysis.

  20. Indirect Energy Flows in Niche Model Food Webs: Effects of Size and Connectance.

    PubMed

    Shevtsov, Jane; Rael, Rosalyn

    2015-01-01

    Indirect interactions between species have long been of interest to ecologists. One such interaction type takes place when energy or materials flow via one or more intermediate species between two species with a direct predator-prey relationship. Previous work has shown that, although each such flow is small, their great number makes them important in ecosystems. A new network analysis method, dynamic environ approximation, was used to quantify the fraction of energy flowing from prey to predator over paths of length greater than 1 (flow indirectness or FI) in a commonly studied food web model. Web structure was created using the niche model and dynamics followed the Yodzis-Innes model. The effect of food web size (10 to 40 species) and connectance (0.1 to 0.48) on FI was examined. For each of 250 model realizations run for each pair of size and connectance values, the FI of every predator-prey interaction in the model was computed and then averaged over the whole network. A classification and regression tree (CART) analysis was then used to find the best predictors of FI. The mean FI of the model food webs is 0.092, with a standard deviation of 0.0279. It tends to increase with system size but peaks at intermediate connectance levels. Of 27 potential predictor variables, only five (mean path length, dominant eigenvalue of the adjacency matrix, connectance, mean trophic level and fraction of species belonging to intermediate trophic levels) were selected by the CART algorithm as best accounting for variation in the data; mean path length and the dominant eigenvalue of the adjacency matrix were dominant.

  1. Regional blood flow and skeletal muscle energy status in endotoxemic rats

    SciTech Connect

    Jepson, M.M.; Cox, M.; Bates, P.C.; Rothwell, N.J.; Stock, M.J.; Cady, E.B.; Millward, D.J.

    1987-05-01

    Endotoxins induce muscle wasting in part as a result of depressed protein synthesis. To investigate whether these changes reflect impaired energy transduction, blood flow, O/sub 2/ extraction, and high-energy phosphates in muscle and whole-body O/sub 2/ consumption (Vo/sub 2/) have been measured. Vo/sub 2/ was measured for 6 h after an initial sublethal dose of endotoxin (Escherichia coli lipopolysaccharide 0.3 mg/100 g body wt sc) or saline and during 6 h after a second dose 24 h later. In fed or fasted rats, Vo/sub 2/ was either increased or better maintained after endotoxin. In anesthetized fed rats 3-4 h after the second dose of endotoxin Vo/sub 2/ was increased, and this was accompanied by increased blood flow measured by /sup 57/Co-labelled microspheres to liver (hepatic arterial supply), kidney, and perirenal brown adipose tissue and a 57 and 64% decrease in flow to back and hindlimb muscle, respectively, with no change in any other organ. Hindlimb arteriovenous O/sub 2/ was unchanged, indicating markedly decreased aerobic metabolism in muscle, and the contribution of the hindlimb to whole-body Vo/sub 2/ decreased by 46%. Adenosine 5'-triphosphate levels in muscle were unchanged in endotoxin-treated rats, and this was confirmed by topical nuclear magnetic resonance spectroscopy, which also showed muscle pH to be unchanged. These results show that, although there is decreased blood flow and aerobic oxidation in muscle, adenosine 5'-triphosphate availability does not appear to be compromised so that the endotoxin-induced muscle catabolism and decreased protein synthesis must reflex some other mechanism.

  2. Modeling of dissociation and energy transfer in shock-heated nitrogen flows

    SciTech Connect

    Munafò, A.; Liu, Y.; Panesi, M.

    2015-12-15

    This work addresses the modeling of dissociation and energy transfer processes in shock heated nitrogen flows by means of the maximum entropy linear model and a newly proposed hybrid bin vibrational collisional model. Both models aim at overcoming two of the main limitations of the state of the art non-equilibrium models: (i) the assumption of equilibrium between rotational and translational energy modes of the molecules and (ii) the reliance on the quasi-steady-state distribution for the description of the population of the internal levels. The formulation of the coarse-grained models is based on grouping the energy levels into bins, where the population is assumed to follow a Maxwell-Boltzmann distribution at its own temperature. Different grouping strategies are investigated. Following the maximum entropy principle, the governing equations are obtained by taking the zeroth and first-order moments of the rovibrational master equations. The accuracy of the proposed models is tested against the rovibrational master equation solution for both flow quantities and population distributions. Calculations performed for free-stream velocities ranging from 5 km/s to 10 km/s demonstrate that dissociation can be accurately predicted by using only 2-3 bins. It is also shown that a multi-temperature approach leads to an under-prediction of dissociation, due to the inability of the former to account for the faster excitation of high-lying vibrational states.

  3. Energy Simulation of Integrated Multiple-Zone Variable Refrigerant Flow System

    SciTech Connect

    Shen, Bo; Rice, C Keith; Baxter, Van D

    2013-01-01

    We developed a detailed steady-state system model, to simulate the performance of an integrated five-zone variable refrigerant flow (VRF)heat pump system. The system is multi-functional, capable of space cooling, space heating, combined space cooling and water heating, and dedicated water heating. Methods were developed to map the VRF performance in each mode, based on the abundant data produced by the equipment system model. The performance maps were used in TRNSYS annual energy simulations. Using TRNSYS, we have successfully setup and run cases for a multiple-split, VRF heat pump and dehumidifier combination in 5-zone houses in 5 climates that control indoor dry-bulb temperature and relative humidity. We compared the calculated energy consumptions for the VRF heat pump against that of a baseline central air source heat pump, coupled with electric water heating and the standalone dehumidifiers. In addition, we investigated multiple control scenarios for the VRF heat pump, i.e. on/off control, variable indoor air flow rate, and using different zone temperature setting schedules, etc. The energy savings for the multiple scenarios were assessed.

  4. Effects of the pulsatile flow settings on pulsatile waveforms and hemodynamic energy in a PediVAS centrifugal pump.

    PubMed

    Wang, Shigang; Rider, Alan R; Kunselman, Allen R; Richardson, J Scott; Dasse, Kurt A; Undar, Akif

    2009-01-01

    The objective of this study was to test different pulsatile flow settings of the PediVAS centrifugal pump to seek an optimum setting for pulsatile flow to achieve better pulsatile energy and minimal backflow. The PediVAS centrifugal pump and the conventional pediatric clinical circuit, including a pediatric membrane oxygenator, arterial filter, arterial cannula, and 1/4 in circuit tubing were used. The circuit was primed with 40% glycerin water mixture. Postcannula pressure was maintained at 40 mm Hg by a Hoffman clamp. The experiment was conducted at 800 ml/min of pump flow with a modified pulsatile flow setting at room temperature. Pump flow and pressure readings at preoxygenator and precannula sites were simultaneously recorded by a data acquisition system. The results showed that backflows appeared at flow rates of 200-800 ml/min (200 ml/min increments) with the default pulsatile flow setting and only at 200 ml/min with the modified pulsatile flow setting. With an increased rotational speed difference ratio and a decreased pulsatile width, the pulsatility increased in terms of surplus hemodynamic energy and total hemodynamic energy at preoxygenator and precannula sites. Backflows seemed at preoxygenator and precannula sites at a 70% of rotational speed difference ratio. The modified pulsatile flow setting was better than the default pulsatile flow setting in respect to pulsatile energy and backflow. The pulsatile width and the rotational speed difference ratio significantly affected pulsatility. The parameter of the rotational speed difference ratio can automatically increase pulsatility with increased rotational speeds. Further studies will be conducted to optimize the pulsatile flow setting of the centrifugal pump.

  5. Mobile Methane Measurements of Natural Gas Distribution and End-use Emissions in Indianapolis

    NASA Astrophysics Data System (ADS)

    Lamb, B. K.; Roscioli, J. R.; Floerchinger, C. R.; Herndon, S. C.; Ferrara, T.

    2015-12-01

    Indianapolis is the site of the INFLUX program to investigate greenhouse gas emissions from a large metropolitan area. A key question in INFLUX is the relative contributions of methane emissions from the local gas distribution system in comparison to biogenic sources, such as the wastewater treatment system and landfills, and of end use emissions from furnaces and other combustion devices downstream of customer gas meters. During February and March, 2015, the Aerodyne van was used to measure methane, ethane, CO2 and other trace gases during mobile sampling traverses through a number of urban and suburban Indianapolis neighborhoods. Signatures of distinct natural gas emissions, biogenic emissions, and combustion emissions were observed in small plumes. In a number of cases, these sources were identified as manhole covers in city streets, where nearby leaks can seep into the local wastewater system. Quantification of ethane and methane from 45 manholes reveal that some had emissions that were clearly biogenic while others had a distinct natural gas signature. This paper describes the results from the analysis of these mobile data in the context of the current Indianapolis methane emission inventory.

  6. Heat and mass transfer in unsteady rotating fluid flow with binary chemical reaction and activation energy.

    PubMed

    Awad, Faiz G; Motsa, Sandile; Khumalo, Melusi

    2014-01-01

    In this study, the Spectral Relaxation Method (SRM) is used to solve the coupled highly nonlinear system of partial differential equations due to an unsteady flow over a stretching surface in an incompressible rotating viscous fluid in presence of binary chemical reaction and Arrhenius activation energy. The velocity, temperature and concentration distributions as well as the skin-friction, heat and mass transfer coefficients have been obtained and discussed for various physical parametric values. The numerical results obtained by (SRM) are then presented graphically and discussed to highlight the physical implications of the simulations. PMID:25250830

  7. Heat and Mass Transfer in Unsteady Rotating Fluid Flow with Binary Chemical Reaction and Activation Energy

    PubMed Central

    Awad, Faiz G.; Motsa, Sandile; Khumalo, Melusi

    2014-01-01

    In this study, the Spectral Relaxation Method (SRM) is used to solve the coupled highly nonlinear system of partial differential equations due to an unsteady flow over a stretching surface in an incompressible rotating viscous fluid in presence of binary chemical reaction and Arrhenius activation energy. The velocity, temperature and concentration distributions as well as the skin-friction, heat and mass transfer coefficients have been obtained and discussed for various physical parametric values. The numerical results obtained by (SRM) are then presented graphically and discussed to highlight the physical implications of the simulations. PMID:25250830

  8. Probing the energy flow in Bessel light beams using atomic photoionization

    NASA Astrophysics Data System (ADS)

    Surzhykov, A.; Seipt, D.; Fritzsche, S.

    2016-09-01

    The growing interest in twisted light beams also requires a better understanding of their complex internal structure. Particular attention is currently being given to the energy circulation in these beams as usually described by the Poynting vector field. In the present study we propose to use the photoionization of alkali-metal atoms as a probe process to measure (and visualize) the energy flow in twisted light fields. Such measurements are possible since the angular distribution of photoelectrons, emitted from a small atomic target, appears sensitive to and is determined by the local direction of the Poynting vector. To illustrate the feasibility of the proposed method, detailed calculations were performed for the ionization of sodium atoms by nondiffractive Bessel beams.

  9. Multiphase flow measurement using multiple energy gamma ray absorption (MEGRA) composition measurement

    SciTech Connect

    Scheers, A.M.; Slijkerman, W.F.J.

    1996-12-31

    Some multiphase flowmeters use the principle of Dual Energy Gamma Ray Absorption (DEGRA) composition measurement to determine the individual water, oil and gas fractions. Under homogeneous flow conditions the ultimate uncertainty in phase fractions achievable with this technique depends strongly on the choice of hardware. The meter presented in this paper uses unique components that have been optimized for the water, oil and gas fraction measurement with theoretical uncertainties of 2% in the fractions over a 1 second measurement period. Generally, composition meters are sensitive to a change in production water salinity and this will cause significant systematic effort in the fraction and watercut measurements. A new measurement concept is presented that is not sensitive to salinity variations and based on Multiple Energy Gamma Ray Absorption (MEGRA) composition measurement. A multiphase flowmeter equipped with the MEGRA concept does not require field-calibration, a decisive advantage in subsea or marginal field developments.

  10. Combining LCT tools for the optimization of an industrial process: material and energy flow analysis and best available techniques.

    PubMed

    Rodríguez, M T Torres; Andrade, L Cristóbal; Bugallo, P M Bello; Long, J J Casares

    2011-09-15

    Life cycle thinking (LCT) is one of the philosophies that has recently appeared in the context of the sustainable development. Some of the already existing tools and methods, as well as some of the recently emerged ones, which seek to understand, interpret and design the life of a product, can be included into the scope of the LCT philosophy. That is the case of the material and energy flow analysis (MEFA), a tool derived from the industrial metabolism definition. This paper proposes a methodology combining MEFA with another technique derived from sustainable development which also fits the LCT philosophy, the BAT (best available techniques) analysis. This methodology, applied to an industrial process, seeks to identify the so-called improvable flows by MEFA, so that the appropriate candidate BAT can be selected by BAT analysis. Material and energy inputs, outputs and internal flows are quantified, and sustainable solutions are provided on the basis of industrial metabolism. The methodology has been applied to an exemplary roof tile manufacture plant for validation. 14 Improvable flows have been identified and 7 candidate BAT have been proposed aiming to reduce these flows. The proposed methodology provides a way to detect improvable material or energy flows in a process and selects the most sustainable options to enhance them. Solutions are proposed for the detected improvable flows, taking into account their effectiveness on improving such flows.

  11. IMPROVING ENERGY EFFICIENCY VIA OPTIMIZED CHARGE MOTION AND SLURRY FLOW IN PLANT SCALE SAG MILLS

    SciTech Connect

    Raj K. Rajamani; Sanjeeva Latchireddi; Sravan K. Prathy; Trilokyanath Patra

    2005-12-01

    The U.S. mining industry operates approximately 80 semi-autogenesis grinding mills (SAG) throughout the United States. Depending on the mill size the SAG mills draws between 2 MW and 17 MW. The product from the SAG mill is further reduced in size using pebble crushers and ball mills. Hence, typical gold or copper ore requires between 2.0 and 7.5 kWh per ton of energy to reduce the particle size. Considering a typical mining operation processes 10,000 to 100,000 tons per day the energy expenditure in grinding is 50 percent of the cost of production of the metal. A research team from the University of Utah is working to make inroads into saving energy in these SAG mills. In 2003, Industries of the Future Program of the Department of Energy tasked the University of Utah team to build a partnership between the University and the mining industry for the specific purpose of reducing energy consumption in SAG mills. A partnership was formed with Cortez Gold Mines, Kennecott Utah Copper Corporation, Process Engineering Resources Inc. and others. In the current project, Cortez Gold Mines played a key role in facilitating the 26-ft SAG mill at Cortez as a test mill for this study. According to plant personnel, there were a number of unscheduled shut downs to repair broken liners and the mill throughput fluctuated depending on ore type. The University team had two softwares, Millsoft and FlowMod to tackle the problem. Millsoft is capable of simulating the motion of charge in the mill. FlowMod calculates the slurry flow through the grate and pulp lifters. Based on this data the two models were fine-tuned to fit the Cortez SAG will. In the summer of 2004 a new design of shell lifters were presented to Cortez and in September 2004 these lifters were installed in the SAG mill. By December 2004 Cortez Mines realized that the SAG mill is drawing approximately 236-kW less power than before while maintaining the same level of production. In the first month there was extreme cycling

  12. Analysis of atmospheric flow over a surface protrusion using the turbulence kinetic energy equation with reference to aeronautical operating systems

    NASA Technical Reports Server (NTRS)

    Frost, W.; Harper, W. L.

    1975-01-01

    Flow over surface obstructions can produce significantly large wind shears such that adverse flying conditions can occur for aeronautical systems (helicopters, STOL vehicles, etc.). Atmospheric flow fields resulting from a semi-elliptical surface obstruction in an otherwise horizontally homogeneous statistically stationary flow are modelled with the boundary-layer/Boussinesq-approximation of the governing equation of fluid mechanics. The turbulence kinetic energy equation is used to determine the dissipative effects of turbulent shear on the mean flow. Iso-lines of turbulence kinetic energy and turbulence intensity are plotted in the plane of the flow and highlight regions of high turbulence intensity in the stagnation zone and sharp gradients in intensity along the transition from adverse to favourable pressure gradient. Discussion of the effects of the disturbed wind field in CTOL and STOL aircraft flight path and obstruction clearance standards is given. The results indicate that closer inspection of these presently recommended standards as influenced by wind over irregular terrains is required.

  13. Application of the methods of gas dynamics to water flows with free surface I : flows with no energy dissipation

    NASA Technical Reports Server (NTRS)

    Preiswerk, Ernst

    1940-01-01

    The application is treated in sufficient detail to facilitate as much as possible its application by the engineer who is less familiar with the subject. The present work was undertaken with two objects in view. In the first place, it is considered as a contribution to the water analogy of gas flows, and secondly, a large portion is devoted to the general theory of the two-dimensional supersonic flows.

  14. Mineral carbonation: energy costs of pretreatment options and insights gained from flow loop reaction studies

    SciTech Connect

    Penner, Larry R.; O'Connor, William K.; Dahlin, David C.; Gerdemann, Stephen J.; Rush, Gilbert E.

    2004-01-01

    Sequestration of carbon as a stable mineral carbonate has been proposed to mitigate environmental concerns that carbon dioxide may with time escape from its sequestered matrix using alternative sequestration technologies. A method has been developed to prepare stable carbonate products by reacting CO2 with magnesium silicate minerals in aqueous bicarbonate/chloride media at high temperature and pressure. Because this approach is inherently expensive due to slow reaction rates and high capital costs, studies were conducted to improve the reaction rates through mineral pretreatment steps and to cut expenses through improved reactor technology. An overview is given for the estimated cost of the process including sensitivity to grinding and heating as pretreatment options for several mineral feedstocks. The energy costs are evaluated for each pretreatment in terms of net carbon avoided. New studies with a high-temperature, high-pressure flow-loop reactor have yielded information on overcoming kinetic barriers experienced with processing in stirred autoclave reactors. Repeated tests with the flow-loop reactor have yielded insights on wear and failure of system components, on challenges to maintain and measure flow, and for better understanding of the reaction mechanism.

  15. Dissociative energy flow, vibrational energy redistribution, and conformeric structural dynamics in bifunctional amine model systems.

    PubMed

    Bush, Joseph C; Minitti, Michael P; Weber, Peter M

    2010-10-28

    Time-resolved multiphoton ionization mass spectrometry coupled with Rydberg Fingerprint Spectroscopy (RFS) has been used to analyze the structural and electronic dynamics of N,N-dimethylphenethylamine (PENNA) and N,N-dimethylcyclohexethylamine (CENNA). In PENNA, the molecule converts from 3p to 3s on a time scale of 149 fs, a process that is reflected in the mass spectrum as the onset of fragmentation. Once in 3s, the overall signal intensity of the PENNA 3s signal shows biexponential decay kinetics, which is attributed to the electronic curve crossing from the Rydberg state to a dissociative antibonding orbital of the ethylenic bridge. This curve crossing exemplifies a possible fragmentation pathway observed in electron capture dissociation of proteins. The initially fast reaction (1.3 ps) is greatly slowed down as a result of an apparent relaxation process with a 5.6 ps time constant. The electron binding energy of the 3s Rydberg state of PENNA is observed to shift with a time constant of 4.8 ps, which is correlated to a cation-π interaction driven conformeric rearrangement.

  16. Significant ELCAP analysis results: Summary report. [End-use Load and Consumer Assessment Program

    SciTech Connect

    Pratt, R.G.; Conner, C.C.; Drost, M.K.; Miller, N.E.; Cooke, B.A.; Halverson, M.A.; Lebaron, B.A.; Lucas, R.G.; Jo, J.; Richman, E.E.; Sandusky, W.F. ); Ritland, K.G. ); Taylor, M.E. ); Hauser, S.G. )

    1991-02-01

    The evolution of the End-Use Load and Consumer Assessment Program (ELCAP) since 1983 at Bonneville Power Administration (Bonneville) has been eventful and somewhat tortuous. The birth pangs of a data set so large and encompassing as this have been overwhelming at times. The early adolescent stage of data set development and use has now been reached and preliminary results of early analyses of the data are becoming well known. However, the full maturity of the data set and the corresponding wealth of analytic insights are not fully realized. This document is in some sense a milestone in the brief history of the program. It is a summary of the results of the first five years of the program, principally containing excerpts from a number of previous reports. It is meant to highlight significant accomplishments and analytical results, with a focus on the principal results. Many of the results have a broad application in the utility load research community in general, although the real breadth of the data set remains largely unexplored. The first section of the document introduces the data set: how the buildings were selected, how the metering equipment was installed, and how the data set has been prepared for analysis. Each of the sections that follow the introduction summarize a particular analytic result. A large majority of the analyses to date involve the residential samples, as these were installed first and had highest priority on the analytic agenda. Two exploratory analyses using commercial data are included as an introduction to the commercial analyses that are currently underway. Most of the sections reference more complete technical reports which the reader should refer to for details of the methodology and for more complete discussion of the results. Sections have been processed separately for inclusion on the data base.

  17. Mechanical energy flow in the recovery leg of elite race walkers.

    PubMed

    Hoga, Koji; Ae, Michiyoshi; Enomoto, Yasushi; Fujii, Norihisa

    2003-01-01

    The purpose of this study was to investigate the mechanical energy flow in the recovery leg and its relationship to performance descriptors of elite male race walkers in an official race. Male race walkers participating in official 20 km races were videotaped with a VTR camera (60 Hz) set perpendicular to the course. The 28 elite race walkers (race records 1:19'50"-1:33'58") were selected as subjects. A two dimensional 14-segment linked model was used to calculate biomechanical parameters from the walking motion in the early phase of the race. The walking speed was significantly related to the step length but not related to the step frequency. Large mechanical energy flows at the hip occurred from the trunk to the foot during the first half of the recovery phase and from the foot to the trunk during the second half by the joint force power. Joint force powers at the hip in the second half of the recovery phase were significantly related to the walking speed and the step length. It is suggested that large joint force power at the hip would be one of the important factors to obtain high walking speed.

  18. Quantum localization and protein-assisted vibrational energy flow in cofactors

    NASA Astrophysics Data System (ADS)

    Leitner, David M.

    2010-08-01

    Quantum effects influence vibrational dynamics and energy flow in biomolecules, which play a central role in biomolecule function, including control of reaction kinetics. Lifetimes of many vibrational modes of proteins and their temperature dependence, as determined by quantum golden-rule-based calculations, exhibit trends consistent with experimental observation and distinct from estimates based on classical modeling. Particularly notable are quantum coherence effects that give rise to localization of vibrational states of sizable organic molecules in the gas phase. Even when such a molecule, for instance a cofactor, is embedded in a protein, remnants of quantum localization survive that influence vibrational energy flow and its dependence on temperature. We discuss these effects on the mode-damping rates of a cofactor embedded in a protein, using the green fluorescent protein chromophore as a specific example. We find that for cofactors of this size embedded in their protein and solvent environment at room temperature a golden-rule calculation often overestimates the mode-damping rate.

  19. Schlieren Visualization of the Energy Addition by Multi Laser Pulse in Hypersonic Flow

    SciTech Connect

    Oliveira, A. C.; Minucci, M. A. S.; Toro, P. G. P.; Chanes, J. B. Jr; Myrabo, L. N.

    2008-04-28

    The experimental results of the energy addition by multi laser pulse in Mach 7 hypersonic flow are presented. Two high power pulsed CO{sub 2} TEA lasers (TEA1 5.5 J, TEA2 3.9 J) were assembled sharing the same optical cavity to generate the plasma upstream of a hemispherical model installed in the tunnel test section. The lasers can be triggered with a selectable time delay and in the present report the results obtained with delay between 30 {mu}s and 80 {mu}s are shown. The schlieren technique associated with a high speed camera was used to accomplish the influence of the energy addition in the mitigation of the shock wave formed on the model surface by the hypersonic flow. A piezoelectric pressure transducer was used to obtain the time history of the impact pressure at stagnation point of the model and the pressure reduction could be measured. The total recovery of the shock wave between pulses as well as the prolonged effect of the mitigation without recovery was observed by changing the delay.

  20. Parametric CFD study of micro-energy harvesting in a flow channel exploiting vortex shedding

    NASA Astrophysics Data System (ADS)

    Koubogiannis, Dimitrios G.

    2016-05-01

    Miniature energy harvesting devices are increasingly used in various fields. For example, Wireless Sensor Networks have recently made great progress in many applications. However, their main drawback, i.e. the limited duration of operation, poses the requirement for an effective way to recharge their batteries. In this context, the presentwork focuses on the study of micro-energy harvesting from flow by exploiting vortex shedding behind bluff bodies, in order to cause oscillations to a piezoelectric film and generate the required electrical power. To this end, a Computational Fluid Dynamics (CFD) tool is validated on a particular miniature device configuration proposed in the literature and implemented for the numerical simulations of flow around bluff micro-bodies in a very small channel. Aiming to enhance vortex shedding, parametric studies corresponding to different bluff body shapes and arrangements for a fixed Reynolds number are performed, the main parameters involved in the phenomenon are highlighted and the potential for vortex shedding exploitation is qualitatively assessed.

  1. UV DRIVEN EVAPORATION OF CLOSE-IN PLANETS: ENERGY-LIMITED, RECOMBINATION-LIMITED, AND PHOTON-LIMITED FLOWS

    SciTech Connect

    Owen, James E.; Alvarez, Marcelo A.

    2016-01-01

    We have investigated the evaporation of close-in exoplanets irradiated by ionizing photons. We find that the properties of the flow are controlled by the ratio of the recombination time to the flow timescale. When the recombination timescale is short compared to the flow timescale, the flow is in approximate local ionization equilibrium with a thin ionization front where the photon mean free path is short compared to the flow scale. In this “recombination-limited” flow the mass-loss scales roughly with the square root of the incident flux. When the recombination time is long compared to the flow timescale the ionization front becomes thick and encompasses the entire flow with the mass-loss rate scaling linearly with flux. If the planet's potential is deep, then the flow is approximately “energy-limited”; however, if the planet's potential is shallow, then we identify a new limiting mass-loss regime, which we term “photon-limited.” In this scenario, the mass-loss rate is purely limited by the incoming flux of ionizing photons. We have developed a new numerical approach that takes into account the frequency dependence of the incoming ionizing spectrum and performed a large suite of 1D simulations to characterize UV driven mass-loss around low-mass planets. We find that the flow is “recombination-limited” at high fluxes but becomes “energy-limited” at low fluxes; however, the transition is broad occurring over several orders of magnitude in flux. Finally, we point out that the transitions between the different flow types do not occur at a single flux value but depend on the planet's properties, with higher-mass planets becoming “energy-limited” at lower fluxes.

  2. CFEST Coupled Flow, Energy & Solute Transport Version CFEST005 User’s Guide

    SciTech Connect

    Freedman, Vicky L.; Chen, Yousu; Gilca, Alex; Cole, Charles R.; Gupta, Sumant K.

    2006-07-20

    The CFEST (Coupled Flow, Energy, and Solute Transport) simulator described in this User’s Guide is a three-dimensional finite-element model used to evaluate groundwater flow and solute mass transport. Confined and unconfined aquifer systems, as well as constant and variable density fluid flows can be represented with CFEST. For unconfined aquifers, the model uses a moving boundary for the water table, deforming the numerical mesh so that the uppermost nodes are always at the water table. For solute transport, changes in concentra¬tion of a single dissolved chemical constituent are computed for advective and hydrodynamic transport, linear sorption represented by a retardation factor, and radioactive decay. Although several thermal parameters described in this User’s Guide are required inputs, thermal transport has not yet been fully implemented in the simulator. Once fully implemented, transport of thermal energy in the groundwater and solid matrix of the aquifer can also be used to model aquifer thermal regimes. The CFEST simulator is written in the FORTRAN 77 language, following American National Standards Institute (ANSI) standards. Execution of the CFEST simulator is controlled through three required text input files. These input file use a structured format of associated groups of input data. Example input data lines are presented for each file type, as well as a description of the structured FORTRAN data format. Detailed descriptions of all input requirements, output options, and program structure and execution are provided in this User’s Guide. Required inputs for auxillary CFEST utilities that aide in post-processing data are also described. Global variables are defined for those with access to the source code. Although CFEST is a proprietary code (CFEST, Inc., Irvine, CA), the Pacific Northwest National Laboratory retains permission to maintain its own source, and to distribute executables to Hanford subcontractors.

  3. Effect of intraprostatic blood flow on laser energy penetration in the canine prostate

    NASA Astrophysics Data System (ADS)

    Cowles, Robert S., III; Hubbard, Bradley S.; Rawlings, Clarence A.

    1995-05-01

    Visual Laser Ablation of the Prostate has been shown to be an effective treatment for the relief of bladder outlet obstruction secondary to benign prostatic hyperplasia. Dosimetry studies using the potato and live canine model are commonly used to advocate application of the Nd:YAG energy into the prostatic tissue. Questions have been raised as to the accuracy of tissue heat penetration in such models based on the scatter and diffusion caused by variations in blood flow and tissue differences from one prostate to another. Thus a study was done to evaluate differences, it any, in heat energy penetration caused by blood flow in the prostate. Mature canine prostates were lased in the (1) live dog, (2) euthanized dog, and (3) en bloc resected canine prostates immersed in a water bath of 101 degree(s)F. Prostates were lased using 60 watts for 60 seconds in the 2, 4, 8, and 10 o'clock positions. One prostate model was lased in the 8 and 10 o'clock positions while alive and then removed in bloc, immersed in a water bath at 101 degree(s)F and lased at the 2 and 4 o'clock positions. A third prostate, having been completely removed two days prior to lasing and frozen, was immersed in a water bath at 101 degree(s)F and lased. The findings indicate in the resected prostate loss of the ring of thermal damage, however, a zone of coagulative necrosis which is consistent with that seen in the live model. Thus blood flow does not appear to have a significant effect on Nd:YAG depth of penetration.

  4. Seventeenth century organic agriculture in China: II. Energy flows through an agroecosystem in Jiaxing Region

    SciTech Connect

    Dazhong, W.; Pimentel, D.

    1986-03-01

    The energy flows in a seventeenth century agroecosystem in Jiaxing Region of eastern China were analyzed on the basis of historical data. The agroecosystem included cropping, mulberry-silkworm livestock, and fishing systems. In terms of energy, the agroecosystem was sustainable. Human labor provided all the power with inputs of about 3700 hr per hectare of farmland. Most or 70% of the labor was expended in the cropping system. Human and animal manure provided most of the nutrients for crop and mulberry production. About two-thirds of the total manure was used in crop production and one-third in the mulberry plantations. The only fossil energy input was a few hand tools. Approximately 55% of the grain was consumed directly by local residents, about one-third of the grain was used to make an alcohol drink and produce distillers' grains, which was fed to pigs, and only 2% of the grains were exported outside the agroecosystem. About two-thirds of the harvested crop residues were used as household fuel, while the remainder was returned to the field as an organic fertilizer. Pork accounted for 85% and silk cocoons 14% of the total animal products produced. Even though the agroecosystem was generally sustainable in terms of energy, the major environmental problem was that two-thirds of the harvested crop residues were used for household fuel. This reduced nutrient cycling in the system. Insufficient land was available to produce fuelwood; thus, crop residues were the primary source of fuel for the people.

  5. Kinetic model for the vibrational energy exchange in flowing molecular gas mixtures. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Offenhaeuser, F.

    1987-01-01

    The present study is concerned with the development of a computational model for the description of the vibrational energy exchange in flowing gas mixtures, taking into account a given number of energy levels for each vibrational degree of freedom. It is possible to select an arbitrary number of energy levels. The presented model uses values in the range from 10 to approximately 40. The distribution of energy with respect to these levels can differ from the equilibrium distribution. The kinetic model developed can be employed for arbitrary gaseous mixtures with an arbitrary number of vibrational degrees of freedom for each type of gas. The application of the model to CO2-H2ON2-O2-He mixtures is discussed. The obtained relations can be utilized in a study of the suitability of radiation-related transitional processes, involving the CO2 molecule, for laser applications. It is found that the computational results provided by the model agree very well with experimental data obtained for a CO2 laser. Possibilities for the activation of a 16-micron and 14-micron laser are considered.

  6. DEVELOPMENT OF A LOW COST INFERENTIAL NATURAL GAS ENERGY FLOW RATE PROTOTYPE RETROFIT MODULE

    SciTech Connect

    E. Kelner; D. George; T. Morrow; T. Owen; M. Nored; R. Burkey; A. Minachi

    2005-05-01

    In 1998, Southwest Research Institute began a multi-year project to develop a working prototype instrument module for natural gas energy measurement. The module will be used to retrofit a natural gas custody transfer flow meter for energy measurement, at a cost an order of magnitude lower than a gas chromatograph. Development and evaluation of the prototype energy meter in 2002-2003 included: (1) refinement of the algorithm used to infer properties of the natural gas stream, such as heating value; (2) evaluation of potential sensing technologies for nitrogen content, improvements in carbon dioxide measurements, and improvements in ultrasonic measurement technology and signal processing for improved speed of sound measurements; (3) design, fabrication and testing of a new prototype energy meter module incorporating these algorithm and sensor refinements; and (4) laboratory and field performance tests of the original and modified energy meter modules. Field tests of the original energy meter module have provided results in close agreement with an onsite gas chromatograph. The original algorithm has also been tested at a field site as a stand-alone application using measurements from in situ instruments, and has demonstrated its usefulness as a diagnostic tool. The algorithm has been revised to use measurement technologies existing in the module to measure the gas stream at multiple states and infer nitrogen content. The instrumentation module has also been modified to incorporate recent improvements in CO{sub 2} and sound speed sensing technology. Laboratory testing of the upgraded module has identified additional testing needed to attain the target accuracy in sound speed measurements and heating value.

  7. Exploiting a nonlinear restoring force to improve the performance of flow energy harvesters

    NASA Astrophysics Data System (ADS)

    Bibo, Amin; Alhadidi, Ali H.; Daqaq, Mohammed F.

    2015-01-01

    This paper investigates employing a nonlinear restoring force to improve the performance of flow energy harvesters (FEHs). To that end, a galloping FEH possessing a quartic potential energy function of the form V =1/2 μy2+1/4 γy4 is considered. This potential function is used to model either a softening (μ > 0, γ < 0), hardening (μ > 0, γ > 0), or bi-stable (μ < 0, γ > 0) restoring force. A physics-based model of the harvester is obtained assuming piezoelectric transduction and a quasi-steady flow field. The model is validated against experimental data and used to obtain a closed-form solution of the response by employing a multiple scaling perturbation analysis using the Jacobi elliptic functions. The attained solution is subsequently used to investigate the influence of the nonlinearity on the performance of the harvester and to illustrate how to optimize the restoring force in order to maximize the output power for given design conditions and airflow parameters. Specifically, it is shown that for similar design parameters and equal magnitudes of μ, and γ, a bi-stable energy harvester outperforms all other configurations as long as the inter-well motions are activated. On the other hand, if the motion of the bi-stable harvester is limited to a single well, then a harvester incorporating a softening nonlinear restoring force outperforms all other configurations. Furthermore, when comparing two FEHs incorporating the same type of restoring force at the optimal load and similar values of μ, then the FEH with the smaller γ is shown to provide higher output power levels.

  8. Uncertainty in life cycle greenhouse gas emissions from United States natural gas end-uses and its effects on policy.

    PubMed

    Venkatesh, Aranya; Jaramillo, Paulina; Griffin, W Michael; Matthews, H Scott

    2011-10-01

    Increasing concerns about greenhouse gas (GHG) emissions in the United States have spurred interest in alternate low carbon fuel sources, such as natural gas. Life cycle assessment (LCA) methods can be used to estimate potential emissions reductions through the use of such fuels. Some recent policies have used the results of LCAs to encourage the use of low carbon fuels to meet future energy demands in the U.S., without, however, acknowledging and addressing the uncertainty and variability prevalent in LCA. Natural gas is a particularly interesting fuel since it can be used to meet various energy demands, for example, as a transportation fuel or in power generation. Estimating the magnitudes and likelihoods of achieving emissions reductions from competing end-uses of natural gas using LCA offers one way to examine optimal strategies of natural gas resource allocation, given that its availability is likely to be limited in the future. In this study, the uncertainty in life cycle GHG emissions of natural gas (domestic and imported) consumed in the U.S. was estimated using probabilistic modeling methods. Monte Carlo simulations are performed to obtain sample distributions representing life cycle GHG emissions from the use of 1 MJ of domestic natural gas and imported LNG. Life cycle GHG emissions per energy unit of average natural gas consumed in the U.S were found to range between -8 and 9% of the mean value of 66 g CO(2)e/MJ. The probabilities of achieving emissions reductions by using natural gas for transportation and power generation, as a substitute for incumbent fuels such as gasoline, diesel, and coal were estimated. The use of natural gas for power generation instead of coal was found to have the highest and most likely emissions reductions (almost a 100% probability of achieving reductions of 60 g CO(2)e/MJ of natural gas used), while there is a 10-35% probability of the emissions from natural gas being higher than the incumbent if it were used as a

  9. Hypersolidus geothermal energy from the moving freeze-fracture-flow boundary

    NASA Astrophysics Data System (ADS)

    Carrigan, Charles; Eichelberger, John; Sigmundsson, Freysteinn; Papale, Paolo; Sun, Yunwei

    2014-05-01

    Rhyolitic magmas at low pressure undergo much of their crystallization over a small temperature interval just above the solidus. This hypersolidus material has a high energy density and effective heat capacity because of stored heat of crystallization, yet may sustain fractures and therefore admit heat exchange with fluids because of its interlocking crystal framework. Rhyolitic magmas emplaced near the liquidus should at first cool rapidly, owing to internal convection, modest crystallization with declining temperature, and extreme temperature gradients at their boundaries. However, once the solidus is approached the rapid rise in effective heat capacity should result in low temperature gradients and rates of heat flow within the bodies. They are suspended for a time in the hypersolidus state. Prodigious quantities of heat can be released from these thermal masses by hydrothermal systems, natural or perhaps stimulated, fracturing their way inward from the margins. The fracture front drives the solidus isotherm ahead of it. Heat of crystallization in front of the advancing solidus is transferred across the thin, moving boundary zone to the external fluid, which advects it away. Once the material is below (outboard of) the solidus, it behaves as normal rock and cools rapidly, having a heat capacity only about 20% that of water. Variations on this theme were published by Lister (1974) for mid-ocean ridges, Hardee (1980) for lava lakes, and Bjornsson et al (1982) for Grimsvotn and Heimaey, who cited possible geothermal energy exploitiation. This scenario is consistent with a number of observations: 1. The geophysical rarity of imaging mostly liquid magma in the shallow crust, despite common petrologic evidence that silicic magma has undergone shallow storage. 2. More common imaging of "partial melt" volumes, whose inferred properties suggest some, but not dominant proportion of melt. 3. Evidence that pure-melt rhyolitic eruptions may have drained relatively shallow

  10. Compare Energy Use in Variable Refrigerant Flow Heat Pumps Field Demonstration and Computer Model

    SciTech Connect

    Sharma, Chandan; Raustad, Richard

    2013-06-01

    Variable Refrigerant Flow (VRF) heat pumps are often regarded as energy efficient air-conditioning systems which offer electricity savings as well as reduction in peak electric demand while providing improved individual zone setpoint control. One of the key advantages of VRF systems is minimal duct losses which provide significant reduction in energy use and duct space. However, there is limited data available to show their actual performance in the field. Since VRF systems are increasingly gaining market share in the US, it is highly desirable to have more actual field performance data of these systems. An effort was made in this direction to monitor VRF system performance over an extended period of time in a US national lab test facility. Due to increasing demand by the energy modeling community, an empirical model to simulate VRF systems was implemented in the building simulation program EnergyPlus. This paper presents the comparison of energy consumption as measured in the national lab and as predicted by the program. For increased accuracy in the comparison, a customized weather file was created by using measured outdoor temperature and relative humidity at the test facility. Other inputs to the model included building construction, VRF system model based on lab measured performance, occupancy of the building, lighting/plug loads, and thermostat set-points etc. Infiltration model inputs were adjusted in the beginning to tune the computer model and then subsequent field measurements were compared to the simulation results. Differences between the computer model results and actual field measurements are discussed. The computer generated VRF performance closely resembled the field measurements.

  11. The thermal effects on high-frequency vibration of beams using energy flow analysis

    NASA Astrophysics Data System (ADS)

    Zhang, Wenbo; Chen, Hualing; Zhu, Danhui; Kong, Xiangjie

    2014-04-01

    In this paper, the energy flow analysis (EFA) method is developed to predict the high-frequency response of beams in a thermal environment, which is a topic of concern in aerospace and automotive industries. The temperature load applied on the structures can generate thermal stresses and change material properties. The wavenumber and group velocity associated with the in-plane axial force arising from thermal stresses are included in the derivation of the governing energy equation, and the input power is obtained from the derived effective bending stiffness. In addition, effect of temperature-dependent material properties is considered in the EFA model. To verify the proposed formulation, numerical simulations are performed for a pinned-pinned beam in a uniform thermal environment. The EFA results are compared with the modal solutions for various frequencies and damping loss factors, and good correlations are observed. The results show that the spatial distributions and levels of energy density can be affected by the thermal effects, and the vibration response of beams increases with temperature.

  12. Information flow and its significance in coherently integrated policymaking for promoting energy efficiency.

    PubMed

    Kua, Harn Wei

    2007-05-01

    Why do negative, unexpected outcomes occur in sustainable development policies? What can we learn from them? Studies have shown clearly that, to be effective, sustainable development policies must be as coherent and integrated as possible; however, policy integration should not evolve into a tool that restricts creativity and undermines the relevance of local policy initiatives. The Coherently Integrated Policymaking frameworks, based on the precept that information flow is pivotal to the success of policymaking, are proposed and then applied to design an integrated energy efficiency policy that coaddresses a set of indicators. These indicators are energy and greenhouse gas reduction, improvement of public's health, increase in material efficiency, enhancementof energy equity, provision of employment and education opportunities, improvement of workers' health, improvement of local economy, and reduction in derived costs for the business community. Our framework also provides guidance for the magnitude of change a policy should introduce at one time, guided by five distinct types of feedback loops that link the different stakeholders involved in the design, implementation, and monitoring of integrated policies.

  13. System size, energy and centrality dependence of strange hadron elliptic flow at STAR

    SciTech Connect

    Masui, Hiroshi

    2008-12-21

    The elliptic flow (v{sub 2}) pattern in terms of hadron mass and transverse momentum p{sub T} is qualitatively described for p{sub T} < 2 GeV/c by ideal hydrodynamics in Au + Au collisions at RHIC. In addition, for p{sub T} = 2-6 GeV/c the measured v{sub 2} follow a universal scaling by the number of quarks explained by quark coalescence/recombination models. These observations suggest that a partonic collectivity develops in the matter in early stage of heavy ion collisions. Centrality as well as system size and energy dependence of the v{sub 2} is important to shed light on the underlying collision dynamics in heavy ion collisions. We present the measurements of centrality dependence of v{sub 2} at {radical}s{sub NN} = 200 and 62.4 GeV in Au + Au and Cu + Cu collisions for K{sub S}{sup 0}, {phi}, {Lambda}, {Xi} and {Omega} at STAR experiment. We focus on the recent Cu + Cu results and discuss the centrality dependence of v{sub 2} as well as the number of quark scaling as a function of transverse kinetic energy at different system size and energies. We also discuss the eccentricity scaled v{sub 2} for identified hadrons and implications that ideal hydrodynamical limit has not been reached at RHIC.

  14. Numerical modeling of plasma meta-materials for electromagnetic energy flow control

    NASA Astrophysics Data System (ADS)

    Kourtzanidis, Konstantinos; Pederson, Dylan; Raja, Laxminarayan

    2015-09-01

    Meta-materials are a new and promising technology that could enable advances in several scientific fields - especially in electromagnetic (EM) energy flow control. These materials though present a major drawback: They can only interact with a limited range of EM frequencies and their structure is pre-defined, rendering them non-tunable and non-reconfigurable. Instead of using structural crystal patterns as in common meta-materials, micro-plasma discharges can be used to control the EM energy propagation. Plasmas present resonant frequencies depending on their degree of ionization - their charged particles density. By adjusting the plasma density, different EM wave frequencies can be manipulated - controlled. In this article, we present 2D and 3D numerical results of plasma meta-materials and their interaction with high frequency (HF) EM waves. Maxwell's equations are coupled with the electron momentum equation and a quasi-neutral fluid description for the plasma dynamics. We study the interaction between a plasma array and HF EM waves demonstrating significant reduction in the transmitted EM energy. Remote ignition of the plasma micro-discharges by the EM waves is also numerically investigated in a simplified configuration. Supported by the Air Force Office of Scientific Research (AFOSR) through a Multi-University Research Initiative (MURI) grant titled ``Plasma-Based Reconfigurable Photonic Crystals and Metamaterials'' with Dr. Mitat Birkan as the program manager.

  15. Analysis of material and energy flow in sewage treatment facilities in Japan.

    PubMed

    Goto, N; Hu, H Y; Lim, B R; Fujie, K

    2001-05-01

    Energy consumption in sewage treatment facilities in Japan has increased due to increasing tap water consumption. To reduce the resource/energy consumption in sewage treatment facilities, measures such as the selection of optimum treatment processes and operating conditions should be considered. The objective of this study is to gather information necessary for the determination of optimum sewage treatment processes and optimum operating conditions. The energy consumption and material flow in sewage treatment facilities in Japan are analyzed using statistical data. In 1994, reuse rate of treated sewage outside the treatment facilities in Japan was 18% of the amount of domestic treated water. In this regard, reuse of water outside facilities should be encouraged. Average electric power consumption per unit volume of wastewater in sewage treatment facilities varies widely from facility to facility and closely correlates with the facility scale. For example, the smaller the facility scale, the larger the electric power consumption. Treatment volume of sewage in smaller facilities is much less than their capacity. 3.7 million t year-1 of dehydration cake is incinerated and 0.1 million t year-1 of it is converted by composting. The recycle rate of the cake was low. Developing a new sludge treatment process other than incineration is necessary.

  16. Geophysical turbulence and the duality of the energy flow across scales.

    PubMed

    Pouquet, A; Marino, R

    2013-12-01

    The ocean and the atmosphere, and hence the climate, are governed at large scale by interactions between pressure gradient and Coriolis and buoyancy forces. This leads to a quasigeostrophic balance in which, in a two-dimensional-like fashion, the energy injected by solar radiation, winds, or tides goes to large scales in what is known as an inverse cascade. Yet, except for Ekman friction, energy dissipation and turbulent mixing occur at a small scale implying the formation of such scales associated with breaking of geostrophic dynamics through wave-eddy interactions or frontogenesis, in opposition to the inverse cascade. Can it be both at the same time? We exemplify here this dual behavior of energy with the help of three-dimensional direct numerical simulations of rotating stratified Boussinesq turbulence. We show that efficient small-scale mixing and large-scale coherence develop simultaneously in such geophysical and astrophysical flows, both with constant flux as required by theoretical arguments, thereby clearly resolving the aforementioned contradiction. PMID:24476276

  17. New understanding of the role of cerebrospinal fluid: offsetting of arterial and brain pulsation and self-dissipation of cerebrospinal fluid pulsatile flow energy.

    PubMed

    Min, Kyung Jay; Yoon, Soo Han; Kang, Jae-Kyu

    2011-06-01

    Many theories have been postulated to date regarding the mechanisms involved in the absorption of the intracranial arterial blood flow energy in the intracranial space, but it is as yet nor clearly defined. The blood flow energy that is transmitted from the heart formulates the cerebrospinal fluid (CSF) pulsatile flow, and is known to constitute the major energy of the CSF flow, while the bulk flow carries only small energy. The intracranial space that is enclosed in a solid cranium and is an isolate system as in the Monroe-Kellie doctrine, and the authors propose to re-analyze the Monroe-Kellie doctrine concept in terms of energy transfer and dissipation of the Windkessel effect. We propose that the large blood flow energy that initiates in the heart is transferred in order of precedence to the arteries, arterioles, brain parenchyma, and finally to CSF within the cranium, in which the energy is confined and unable to be transferred, so that the final transfer of energy to the CSF pulsatile flow is self-dissipated in terms of direction and chronology in CSF pulsatile flow. In order for the CSF pulsatile flow that is transferred from arterial blood flow energy to be dissipated in the intracranial space, this cannot be explained with bulk flow energy in any perspective, since the pulsatile flow kinetic energy is greater than the bulk flow kinetic energy by at least a 100-fold. The pulsatile flow energy within the closed intracranial space cannot be transferred and is confined, as postulated by the Monroe-Kellie doctrine, and therefore the authors propound that the pulsatile flow dissipates by itself. The dissipation of the CSF pulsatile flow kinetic energy will be in all directions in a diffuse and random manner, and is offset by the CSF flow energy vector due to the CSF mixing process. Such energy dissipation will lead to maintenance of low CSF flow energy, which will result in maintaining low intracranial pressure (ICP), and sufficient brain perfusion. It is our

  18. New Class of Flow Batteries for Terrestrial and Aerospace Energy Storage Applications

    NASA Technical Reports Server (NTRS)

    Bugga, Ratnakumar V.; West, William C.; Kindler, Andrew; Smart, Marshall C.

    2013-01-01

    Future sustainable energy generation technologies such as photovoltaic and wind farms require advanced energy storage systems on a massive scale to make the alternate (green) energy options practical. The daunting requirements of such large-scale energy systems such as long operating and cycle life, safety, and low cost are not adequately met by state-of-the-art energy storage technologies such as vanadium flow cells, lead-acid, and zinc-bromine batteries. Much attention is being paid to redox batteries specifically to the vanadium redox battery (VRB) due to their simplicity, low cost, and good life characteristics compared to other related battery technologies. NASA is currently seeking high-specific- energy and long-cycle-life rechargeable batteries in the 10-to-100-kW range to support future human exploration missions, such as planetary habitats, human rovers, etc. The flow batteries described above are excellent candidates for these applications, as well as other applications that propose to use regenerative fuel cells. A new flow cell technology is proposed based on coupling two novel electrodes in the form of solvated electron systems (SES) between an alkali (or alkaline earth) metal and poly aromatic hydrocarbons (PAH), separated by an ionically conducting separator. The cell reaction involves the formation of such SES with a PAH of high voltage in the cathode, while the alkali (or alkaline earth metal) is reduced from such an MPAH complex in the anode half-cell. During recharge, the reactions are reversed in both electrodes. In other words, the alkali (alkaline earth) metal ion simply shuttles from one M-PAH complex (SES) to another, which are separated by a metal-ion conducting solid or polymer electrolyte separator. As an example, the concept was demonstrated with Li-naphthalene//Li DDQ (DDQ is 2,3-Dichloro-5,6-dicyano- 1,4-benzoquinone) separated by lithium super ion conductor, either ceramic or polymer (solid polymer or gel polymer) electrolytes. The

  19. Buoyant Turbulent Kinetic Energy Production in Steep-Slope Katabatic Flow

    NASA Astrophysics Data System (ADS)

    Oldroyd, Holly J.; Pardyjak, Eric R.; Higgins, Chad W.; Parlange, Marc B.

    2016-07-01

    We develop several critical concepts that should be considered when interpreting, modelling and designing future experiments for flows over sloping terrain. Vertical buoyancy fluxes in katabatic flows can be positive and a source of turbulent kinetic energy (TKE) despite the statically stable, thermal stratification that drives these flows. This phenomenon occurs when the ratio of along-slope to slope-normal kinematic heat fluxes is greater than the cotangent of the slope angle, suggesting a critical value of slope-angle steepness found in earlier studies. We provide field-data-based evidence that the along-slope heat flux may dominate the variables in this inequality, and therefore in generating buoyant TKE production or suppression over a steep slope. These data show the along-slope heat flux can be more variable and significantly larger in magnitude than the slope-normal component. The gradient Richardson number does not include the effects of the along-slope buoyancy; furthermore, none of the canonical stability parameters can properly reflect the TKE redistribution from turbulent transport divergence and the sink of TKE in cases of counter-gradient momentum fluxes, which we frequently observe near the peak of the katabatic jet. In such cases, canonical stability parameters inadequately represent the physical mechanisms associated with stability. These results have broad implications related to accurately modelling turbulence and surface exchanges over sloping terrain and illustrate the need to more thoroughly investigate the along-slope heat flux and its drivers, the meaning and definitions of stability, and the effects of non-local turbulent transport.

  20. Measurement of Electromagnetic Energy Flow Through a Sparse Particulate Medium: A Perspective

    NASA Technical Reports Server (NTRS)

    Mishchenko, Michael I.

    2013-01-01

    First-principle analysis of the functional design of a well-collimated radiometer (WCR) reveals that in general, this instrument does not record the instantaneous directional flow of electromagnetic energy. Only in special cases can a sequence of measurements with a WCR yield the magnitude and direction of the local time-averaged Poynting vector. Our analysis demonstrates that it is imperative to clearly formulate the physical nature of the actual measurement afforded by a directional radiometer rather than presume desirable measurement capabilities. Only then can the directional radiometer be considered a legitimate part of physically based remote sensing and radiation-budget applications. We also emphasize the need for a better understanding of the nature of measurements with panoramic radiometers.

  1. Damage evaluation based on a wave energy flow map using multiple PZT sensors.

    PubMed

    Liu, Yaolu; Hu, Ning; Xu, Hong; Yuan, Weifeng; Yan, Cheng; Li, Yuan; Goda, Riu; Alamusi, Emptyyn Y; Qiu, Jinhao; Ning, Huiming; Wu, Liangke

    2014-01-23

    A new wave energy flow (WEF) map concept was proposed in this work. Based on it, an improved technique incorporating the laser scanning method and Betti's reciprocal theorem was developed to evaluate the shape and size of damage as well as to realize visualization of wave propagation. In this technique, a simple signal processing algorithm was proposed to construct the WEF map when waves propagate through an inspection region, and multiple lead zirconate titanate (PZT) sensors were employed to improve inspection reliability. Various damages in aluminum and carbon fiber reinforced plastic laminated plates were experimentally and numerically evaluated to validate this technique. The results show that it can effectively evaluate the shape and size of damage from wave field variations around the damage in the WEF map.

  2. Damage Evaluation Based on a Wave Energy Flow Map Using Multiple PZT Sensors

    PubMed Central

    Liu, Yaolu; Hu, Ning; Xu, Hong; Yuan, Weifeng; Yan, Cheng; Li, Yuan; Goda, Riu; Alamusi; Qiu, Jinhao; Ning, Huiming; Wu, Liangke

    2014-01-01

    A new wave energy flow (WEF) map concept was proposed in this work. Based on it, an improved technique incorporating the laser scanning method and Betti's reciprocal theorem was developed to evaluate the shape and size of damage as well as to realize visualization of wave propagation. In this technique, a simple signal processing algorithm was proposed to construct the WEF map when waves propagate through an inspection region, and multiple lead zirconate titanate (PZT) sensors were employed to improve inspection reliability. Various damages in aluminum and carbon fiber reinforced plastic laminated plates were experimentally and numerically evaluated to validate this technique. The results show that it can effectively evaluate the shape and size of damage from wave field variations around the damage in the WEF map. PMID:24463430

  3. Design and experimental evaluation of flextensional-cantilever based piezoelectric transducers for flow energy harvesting

    NASA Astrophysics Data System (ADS)

    Lee, Hyeong Jae; Sherrit, Stewart; Tosi, Luis Phillipe; Colonius, Tim

    2016-04-01

    Cantilever type piezoelectric harvesters, such as bimorphs, are typically used for vibration induced energy harvesting. However, a major drawback of a piezoelectric bimorph is its brittle nature in harsh environments, precipitating short life-times as well as output power degradation. The emphasis in this work is to design robust, highly efficient piezoelectric harvesters that are capable of generating electrical power in the milliwatt range. Various harvesters were modeled, designed and prototyped, and the flextensional actuator based harvester, where the metal cantilever is mounted and coupled between two flextensional actuators, was found to be a viable alternative to the cantilever type piezoelectric harvesters. Preliminary tests show that these devices equipped with 5x5x36 mm two piezoelectric PZT stacks can produce greater than 50 mW of power under air flow induced vibrations.

  4. Levelized cost of energy and sensitivity analysis for the hydrogen-bromine flow battery

    NASA Astrophysics Data System (ADS)

    Singh, Nirala; McFarland, Eric W.

    2015-08-01

    The technoeconomics of the hydrogen-bromine flow battery are investigated. Using existing performance data the operating conditions were optimized to minimize the levelized cost of electricity using individual component costs for the flow battery stack and other system units. Several different configurations were evaluated including use of a bromine complexing agent to reduce membrane requirements. Sensitivity analysis of cost is used to identify the system elements most strongly influencing the economics. The stack lifetime and round-trip efficiency of the cell are identified as major factors on the levelized cost of electricity, along with capital components related to hydrogen storage, the bipolar plate, and the membrane. Assuming that an electrocatalyst and membrane with a lifetime of 2000 cycles can be identified, the lowest cost market entry system capital is 220 kWh-1 for a 4 h discharge system and for a charging energy cost of 0.04 kWh-1 the levelized cost of the electricity delivered is 0.40 kWh-1. With systems manufactured at large scales these costs are expected to be lower.

  5. Impact of the postpump resistance on pressure-flow waveform and hemodynamic energy level in a neonatal pulsatile centrifugal pump.

    PubMed

    Wang, Shigang; Haines, Nikkole; Richardson, J Scott; Dasse, Kurt A; Undar, Akif

    2009-01-01

    This study tested the impact of different postpump resistances on pulsatile pressure-flow waveforms and hemodynamic energy output in a mock extracorporeal system. The circuit was primed with a 40% glycerin-water mixture, and a PediVAS centrifugal pump was used. The pre- and postpump pressures and flow rates were monitored via a data acquisition system. The postpump resistance was adjusted using a Hoffman clamp at the outlet of the pump. Five different postpump resistances and rotational speeds were tested with nonpulsatile (NP: 5000 RPM) and pulsatile (P: 4000 RPM) modes. No backflow was found when using pulsatile flow. With isoresistance, increased arterial resistances decreased pump flow rates (NP: from 1,912 ml/min to 373 ml/min; P: from 1,485 ml/min to 288 ml/min), increased postpump pressures (NP: from 333 mm Hg to 402 mm Hg; P: from 223 mm Hg to 274 mm Hg), and increased hemodynamic energy output with pulsatile mode. Pump flow rate correlated linearly with rotational speed (RPMs) of the pump, whereas postpump pressures and hemodynamic energy outputs showed curvilinear relationships with RPMs. The maximal pump flow rate also increased from 618 ml/min to 4,293 ml/min with pulsatile mode and from 581 ml/min to 5,665 ml/min with nonpulsatile mode. Results showed that higher postpump resistance reduced the pump flow range, and increased postpump pressure and surplus hemodynamic energy output with pulsatile mode. Higher rotational speeds also generated higher pump flow rates, postpump pressures, and increased pulsatility.

  6. The principle of 'maximum energy dissipation': a novel thermodynamic perspective on rapid water flow in connected soil structures.

    PubMed

    Zehe, Erwin; Blume, Theresa; Blöschl, Günter

    2010-05-12

    Preferential flow in biological soil structures is of key importance for infiltration and soil water flow at a range of scales. In the present study, we treat soil water flow as a dissipative process in an open non-equilibrium thermodynamic system, to better understand this key process. We define the chemical potential and Helmholtz free energy based on soil physical quantities, parametrize a physically based hydrological model based on field data and simulate the evolution of Helmholtz free energy in a cohesive soil with different populations of worm burrows for a range of rainfall scenarios. The simulations suggest that flow in connected worm burrows allows a more efficient redistribution of water within the soil, which implies a more efficient dissipation of free energy/higher production of entropy. There is additional evidence that the spatial pattern of worm burrow density at the hillslope scale is a major control of energy dissipation. The pattern typically found in the study is more efficient in dissipating energy/producing entropy than other patterns. This is because upslope run-off accumulates and infiltrates via the worm burrows into the dry soil in the lower part of the hillslope, which results in an overall more efficient dissipation of free energy. PMID:20368256

  7. An energy signature scheme for steam trap assessment and flow rate estimation using pipe-induced acoustic measurements

    NASA Astrophysics Data System (ADS)

    Olama, Mohammed M.; Allgood, Glenn O.; Kuruganti, Teja P.; Lake, Joe E.

    2012-06-01

    The US Congress has passed legislation dictating that all government agencies establish a plan and process for improving energy efficiencies at their sites. In response to this legislation, Oak Ridge National Laboratory (ORNL) has recently conducted a pilot study to explore the deployment of a wireless sensor system for a real-time measurement-based energy efficiency optimization framework within the steam distribution system within the ORNL campus. We make assessments on the real-time status of the distribution system by observing the state measurements of acoustic sensors mounted on the steam pipes/traps/valves. In this paper, we describe a spectral-based energy signature scheme that interprets acoustic vibration sensor data to estimate steam flow rates and assess steam traps health status. Experimental results show that the energy signature scheme has the potential to identify different steam trap health status and it has sufficient sensitivity to estimate steam flow rate. Moreover, results indicate a nearly quadratic relationship over the test region between the overall energy signature factor and flow rate in the pipe. The analysis based on estimated steam flow and steam trap status helps generate alerts that enable operators and maintenance personnel to take remedial action. The goal is to achieve significant energy-saving in steam lines by monitoring and acting on leaking steam pipes/traps/valves.

  8. The principle of ‘maximum energy dissipation’: a novel thermodynamic perspective on rapid water flow in connected soil structures

    PubMed Central

    Zehe, Erwin; Blume, Theresa; Blöschl, Günter

    2010-01-01

    Preferential flow in biological soil structures is of key importance for infiltration and soil water flow at a range of scales. In the present study, we treat soil water flow as a dissipative process in an open non-equilibrium thermodynamic system, to better understand this key process. We define the chemical potential and Helmholtz free energy based on soil physical quantities, parametrize a physically based hydrological model based on field data and simulate the evolution of Helmholtz free energy in a cohesive soil with different populations of worm burrows for a range of rainfall scenarios. The simulations suggest that flow in connected worm burrows allows a more efficient redistribution of water within the soil, which implies a more efficient dissipation of free energy/higher production of entropy. There is additional evidence that the spatial pattern of worm burrow density at the hillslope scale is a major control of energy dissipation. The pattern typically found in the study is more efficient in dissipating energy/producing entropy than other patterns. This is because upslope run-off accumulates and infiltrates via the worm burrows into the dry soil in the lower part of the hillslope, which results in an overall more efficient dissipation of free energy. PMID:20368256

  9. Energy law preserving C{sup 0} finite element schemes for phase field models in two-phase flow computations

    SciTech Connect

    Hua Jinsong; Lin Ping; Liu Chun; Wang Qi

    2011-08-10

    Highlights: {yields} We study phase-field models for multi-phase flow computation. {yields} We develop an energy-law preserving C0 FEM. {yields} We show that the energy-law preserving method work better. {yields} We overcome unphysical oscillation associated with the Cahn-Hilliard model. - Abstract: We use the idea in to develop the energy law preserving method and compute the diffusive interface (phase-field) models of Allen-Cahn and Cahn-Hilliard type, respectively, governing the motion of two-phase incompressible flows. We discretize these two models using a C{sup 0} finite element in space and a modified midpoint scheme in time. To increase the stability in the pressure variable we treat the divergence free condition by a penalty formulation, under which the discrete energy law can still be derived for these diffusive interface models. Through an example we demonstrate that the energy law preserving method is beneficial for computing these multi-phase flow models. We also demonstrate that when applying the energy law preserving method to the model of Cahn-Hilliard type, un-physical interfacial oscillations may occur. We examine the source of such oscillations and a remedy is presented to eliminate the oscillations. A few two-phase incompressible flow examples are computed to show the good performance of our method.

  10. An Energy Signature Scheme for Steam Trap Assessment and Flow Rate Estimation Using Pipe-Induced Acoustic Measurements

    SciTech Connect

    Olama, Mohammed M; Allgood, Glenn O; Kuruganti, Phani Teja; Lake, Joe E

    2012-01-01

    The US Congress has passed legislation dictating that all government agencies establish a plan and process for improving energy efficiencies at their sites. In response to this legislation, Oak Ridge National Laboratory (ORNL) has recently conducted a pilot study to explore the deployment of a wireless sensor system for a real-time measurement-based energy efficiency optimization framework within the steam distribution system within the ORNL campus. We make assessments on the real-time status of the distribution system by observing the state measurements of acoustic sensors mounted on the steam pipes/traps/valves. In this paper, we describe a spectral-based energy signature scheme that interprets acoustic vibration sensor data to estimate steam flow rates and assess steam traps health status. Experimental results show that the energy signature scheme has the potential to identify different steam trap health status and it has sufficient sensitivity to estimate steam flow rate. Moreover, results indicate a nearly quadratic relationship over the test region between the overall energy signature factor and flow rate in the pipe. The analysis based on estimated steam flow and steam trap status helps generate alerts that enable operators and maintenance personnel to take remedial action. The goal is to achieve significant energy-saving in steam lines by monitoring and acting on leaking steam pipes/traps/valves.

  11. Effect of Radial Density Configuration on Wave Field and Energy Flow in Axially Uniform Helicon Plasma

    NASA Astrophysics Data System (ADS)

    Chang, Lei; Li, Qingchong; Zhang, Huijie; Li, Yinghong; Wu, Yun; Zhang, Bailing; Zhuang, Zhong

    2016-08-01

    The effect of the radial density configuration in terms of width, edge gradient and volume gradient on the wave field and energy flow in an axially uniform helicon plasma is studied in detail. A three-parameter function is employed to describe the density, covering uniform, parabolic, linear and Gaussian profiles. It finds that the fraction of power deposition near the plasma edge increases with density width and edge gradient, and decays in exponential and “bump-on-tail” profiles, respectively, away from the surface. The existence of a positive second-order derivative in the volume density configuration promotes the power deposition near the plasma core, which to our best knowledge has not been pointed out before. The transverse structures of wave field and current density remain almost the same during the variation of density width and gradient, confirming the robustness of the m=1 mode observed previously. However, the structure of the electric wave field changes significantly from a uniform density configuration, for which the coupling between the Trivelpiece-Gould (TG) mode and the helicon mode is very strong, to non-uniform ones. The energy flow in the cross section of helicon plasma is presented for the first time, and behaves sensitive to the density width and edge gradient but insensitive to the volume gradient. Interestingly, the radial distribution of power deposition resembles the radial profile of the axial component of current density, suggesting the control of the power deposition profile in the experiment by particularly designing the antenna geometry to excite a required axial current distribution. supported by National Natural Science Foundation of China (No. 11405271)

  12. Assessing the effusion rate of lava flows from their thermal radiated energy: theoretical study and lab-scale experiments

    NASA Astrophysics Data System (ADS)

    Garel, F.; Kaminski, E.; Tait, S.; Limare, A.

    2010-12-01

    A quantitative monitoring of lava flow is required to manage a volcanic crisis, in order to assess where the flow will go, and when will it stop. As the spreading of lava flows is mainly controlled by its rheology and the eruptive mass flux, the key question is how to evaluate them during the eruption (rather than afterwards.) A relationship between the lava flow temperature and the eruption rate is likely to exist, based on the first-order argument that higher eruption rates should correspond to larger energy radiated by a lava flow. The semi-empirical formula developed by Harris and co-workers (e.g. Harris et al., 2007) is used to estimate lava flow rate from satellite observations. However, the complete theoretical bases of this technique, especially its domain of validity, remain to be firmly established. Here we propose a theoretical study of the cooling of a viscous axisymmetric gravity current fed at constant flux rate to investigate whether or not this approach can and/or should be refined and/or modify to better assess flow rates. Our study focuses on the influence of boundary conditions at the surface of the flow, where cooling can occur both by radiation and convection, and at the base of the flow. Dimensionless numbers are introduced to quantify the relative interplay between the model parameters, such as the lava flow rate and the efficiency of the various cooling processes (conduction, convection, radiation.) We obtain that the thermal evolution of the flow can be described as a two-stage evolution. After a transient phase of dynamic cooling, the flow reaches a steady state, characterized by a balance between surface and base cooling and heat advection in the flow, in which the surface temperature structure is constant. The duration of the transient phase and the radiated energy in the steady regime are shown to be a function of the dimensionless numbers. In the case of lava flows, we obtain that the steady state regime is reached after a few days. In

  13. Energy dependence of elliptic flow from heavy-ion collision models

    SciTech Connect

    Nasim, Md.; Mohanty, Bedangadas; Kumar, Lokesh; Netrakanti, Pawan Kumar

    2010-11-15

    We have compared the experimental data on charged-particle elliptic flow parameter (v{sub 2}) in Au + Au collisions at midrapidity for {radical}(s{sub NN})=9.2, 19.6, 62.4, and 200 GeV with results from various models in heavy-ion collisions such as the ultrarelativistic quantum molecular dynamics (UrQMD) model, a multiphase transport model (AMPT), and heavy-ion jet interaction generator (HIJING). We observe that the average v{sub 2} () from the transport model UrQMD agrees well with the measurements at {radical}(s{sub NN})=9.2 GeV but increasingly falls short of the experimental values as the beam energy increases. The difference in is of the order of 60% at {radical}(s{sub NN})=200 GeV. The results from HIJING are consistent with zero, while those from AMPT with default settings, a model based on HIJING with additional initial- and final-state rescattering effects included, give a value of about 4% for all the beam energies studied. This is in contrast to an increase in with beam energy for the experimental data. A different version of the AMPT model, which includes partonic effects and quark coalescence as a mechanism of hadronization, gives higher values of among the models studied and is in agreement with the measured values at {radical}(s{sub NN})=200 GeV. These studies show that the experimental has substantial contribution from partonic interactions at {radical}(s{sub NN})=200 GeV, whose magnitude reduces with decrease in beam energy. We also compare the available data on the transverse momentum and pseudorapidity dependence of v{sub 2} to those from these models.

  14. Water flows, energy demand, and market analysis of the informal water sector in Kisumu, Kenya.

    PubMed

    Sima, Laura C; Kelner-Levine, Evan; Eckelman, Matthew J; McCarty, Kathleen M; Elimelech, Menachem

    2013-03-01

    In rapidly growing urban areas of developing countries, infrastructure has not been able to cope with population growth. Informal water businesses fulfill unmet water supply needs, yet little is understood about this sector. This paper presents data gathered from quantitative interviews with informal water business operators (n=260) in Kisumu, Kenya, collected during the dry season. Sales volume, location, resource use, and cost were analyzed by using material flow accounting and spatial analysis tools. Estimates show that over 76% of the city's water is consumed by less than 10% of the population who have water piped into their dwellings. The remainder of the population relies on a combination of water sources, including water purchased directly from kiosks (1.5 million m(3) per day) and delivered by hand-drawn water-carts (0.75 million m(3) per day). Energy audits were performed to compare energy use among various water sources in the city. Water delivery by truck is the highest per cubic meter energy demand (35 MJ/m(3)), while the city's tap water has the highest energy use overall (21,000 MJ/day). We group kiosks by neighborhood and compare sales volume and cost with neighborhood-level population data. Contrary to popular belief, we do not find evidence of price gouging; the lowest prices are charged in the highest-demand low-income area. We also see that the informal sector is sensitive to demand, as the number of private boreholes that serve as community water collection points are much larger where demand is greatest.

  15. Water flows, energy demand, and market analysis of the informal water sector in Kisumu, Kenya

    PubMed Central

    Sima, Laura C.; Kelner-Levine, Evan; Eckelman, Matthew J.; McCarty, Kathleen M.; Elimelech, Menachem

    2013-01-01

    In rapidly growing urban areas of developing countries, infrastructure has not been able to cope with population growth. Informal water businesses fulfill unmet water supply needs, yet little is understood about this sector. This paper presents data gathered from quantitative interviews with informal water business operators (n=260) in Kisumu, Kenya, collected during the dry season. Sales volume, location, resource use, and cost were analyzed by using material flow accounting and spatial analysis tools. Estimates show that over 76% of the city's water is consumed by less than 10% of the population who have water piped into their dwellings. The remainder of the population relies on a combination of water sources, including water purchased directly from kiosks (1.5 million m3 per day) and delivered by hand-drawn water-carts (0.75 million m3 per day). Energy audits were performed to compare energy use among various water sources in the city. Water delivery by truck is the highest per cubic meter energy demand (35 MJ/m3), while the city's tap water has the highest energy use overall (21,000 MJ/day). We group kiosks by neighborhood and compare sales volume and cost with neighborhood-level population data. Contrary to popular belief, we do not find evidence of price gouging; the lowest prices are charged in the highest-demand low-income area. We also see that the informal sector is sensitive to demand, as the number of private boreholes that serve as community water collection points are much larger where demand is greatest. PMID:23543887

  16. Analysis of free-surface flows through energy considerations: Single-phase versus two-phase modeling

    NASA Astrophysics Data System (ADS)

    Marrone, Salvatore; Colagrossi, Andrea; Di Mascio, Andrea; Le Touzé, David

    2016-05-01

    The study of energetic free-surface flows is challenging because of the large range of interface scales involved due to multiple fragmentations and reconnections of the air-water interface with the formation of drops and bubbles. Because of their complexity the investigation of such phenomena through numerical simulation largely increased during recent years. Actually, in the last decades different numerical models have been developed to study these flows, especially in the context of particle methods. In the latter a single-phase approximation is usually adopted to reduce the computational costs and the model complexity. While it is well known that the role of air largely affects the local flow evolution, it is still not clear whether this single-phase approximation is able to predict global flow features like the evolution of the global mechanical energy dissipation. The present work is dedicated to this topic through the study of a selected problem simulated with both single-phase and two-phase models. It is shown that, interestingly, even though flow evolutions are different, energy evolutions can be similar when including or not the presence of air. This is remarkable since, in the problem considered, with the two-phase model about half of the energy is lost in the air phase while in the one-phase model the energy is mainly dissipated by cavity collapses.

  17. Analysis of free-surface flows through energy considerations: Single-phase versus two-phase modeling.

    PubMed

    Marrone, Salvatore; Colagrossi, Andrea; Di Mascio, Andrea; Le Touzé, David

    2016-05-01

    The study of energetic free-surface flows is challenging because of the large range of interface scales involved due to multiple fragmentations and reconnections of the air-water interface with the formation of drops and bubbles. Because of their complexity the investigation of such phenomena through numerical simulation largely increased during recent years. Actually, in the last decades different numerical models have been developed to study these flows, especially in the context of particle methods. In the latter a single-phase approximation is usually adopted to reduce the computational costs and the model complexity. While it is well known that the role of air largely affects the local flow evolution, it is still not clear whether this single-phase approximation is able to predict global flow features like the evolution of the global mechanical energy dissipation. The present work is dedicated to this topic through the study of a selected problem simulated with both single-phase and two-phase models. It is shown that, interestingly, even though flow evolutions are different, energy evolutions can be similar when including or not the presence of air. This is remarkable since, in the problem considered, with the two-phase model about half of the energy is lost in the air phase while in the one-phase model the energy is mainly dissipated by cavity collapses.

  18. Analysis of free-surface flows through energy considerations: Single-phase versus two-phase modeling.

    PubMed

    Marrone, Salvatore; Colagrossi, Andrea; Di Mascio, Andrea; Le Touzé, David

    2016-05-01

    The study of energetic free-surface flows is challenging because of the large range of interface scales involved due to multiple fragmentations and reconnections of the air-water interface with the formation of drops and bubbles. Because of their complexity the investigation of such phenomena through numerical simulation largely increased during recent years. Actually, in the last decades different numerical models have been developed to study these flows, especially in the context of particle methods. In the latter a single-phase approximation is usually adopted to reduce the computational costs and the model complexity. While it is well known that the role of air largely affects the local flow evolution, it is still not clear whether this single-phase approximation is able to predict global flow features like the evolution of the global mechanical energy dissipation. The present work is dedicated to this topic through the study of a selected problem simulated with both single-phase and two-phase models. It is shown that, interestingly, even though flow evolutions are different, energy evolutions can be similar when including or not the presence of air. This is remarkable since, in the problem considered, with the two-phase model about half of the energy is lost in the air phase while in the one-phase model the energy is mainly dissipated by cavity collapses. PMID:27300984

  19. Zonal-flow-driven nonlinear energy transfer in experiment and simulation

    SciTech Connect

    Holland, C.; Tynan, G. R.; Fonck, R. J.; McKee, G. R.; Candy, J.; Waltz, R. E.

    2007-05-15

    Using a newly developed algorithm, the nonlinear transfer of internal fluctuation energy vertical bar n-tilde vertical bar{sup 2} due to convection of drift-wave turbulence by a geodesic acoustic mode (GAM, a finite-frequency zonal flow) has now been measured directly in a high-temperature plasma. By combining spatially resolved density fluctuation measurements obtained via an upgraded beam emission spectroscopy system in the edge region of the DIII-D tokamak [J. L. Luxon, Nucl. Fusion 42, 614 (2002)] with a velocity inference algorithm, the convection of turbulent fluctuations by the GAM has been measured. Taken together, the results strongly suggest that GAM convection of turbulence leads to a transfer of internal fluctuation energy from low to high frequencies, in agreement with expectations from theory and simulation. In addition, the GAM is found to modulate the intensity of the density fluctuations. Calculations of the measured nonlinear interactions in the gyrokinetic code GYRO are found to be in good qualitative agreement with the experimental observations.

  20. Cyclic Performance Analysis of Hydrogen/Bromine Flow Batteries for Grid-Scale Energy Storage

    SciTech Connect

    Cho, KT; Tucker, MC; Ding, M; Ridgway, P; Battaglia, VS; Srinivasan, V; Weber, AZ

    2014-06-03

    This paper explores the critical factors dominating the cycle performance of the hydrogen/bromine redox flow battery (RFB). Carbon electrode oxidation to CO2 was seen as the dominant side reaction, which can be prevented by operating the cell below 1.4 V. Crossover of bromide species from the positive to the negative electrode, especially during charge, dominates the coulombic efficiency, and can result in dissolution of the Pt catalyst if an adequate hydrogen supply is not maintained. This paper also describes the tradeoffs in voltaic, energy, and coulombic efficiencies during cycling, including the determination of the peak energy efficiency with respect to the HBr concentration and current density. Long-term cycling demonstrates negligible cell-component degradation over 600 cycles (approximate to 3 months), with capacity loss caused by the bromine from the system, which can be mitigated by proper system design. The data and methodologies provided in this paper can be used to understand better the operation of this and other RFBs.