Science.gov

Sample records for district cooling phase

  1. District cooling gets hot

    SciTech Connect

    Seeley, R.S.

    1996-07-01

    Utilities across the country are adopting cool storage methods, such as ice-storage and chilled-water tanks, as an economical and environmentally safe way to provide cooling for cities and towns. The use of district cooling, in which cold water or steam is pumped to absorption chillers and then to buildings via a central community chiller plant, is growing strongly in the US. In Chicago, San Diego, Pittsburgh, Baltimore, and elsewhere, independent district-energy companies and utilities are refurbishing neglected district-heating systems and adding district cooling, a technology first developed approximately 35 years ago.

  2. Assessment of impact of advanced energy transmission fluids on district heating and cooling systems (Phase 1)

    SciTech Connect

    Kasza, K.E.; Chen, M.M.

    1987-09-01

    Argonne National Laboratory (ANL), under sponsorship of the US Department of Energy (DOE) Office of Buildings and Community Systems, has embarked upon a comprehensive, long-range program to develop high-performance advanced energy transmission fluids for use in district heating and cooling (DHC) systems. ANL has the lead technical role in this DOE program. These advanced fluids will substantially reduce flow frictional losses and enhance energy transfer. In system enhancement scoping studies conducted by ANL, the fluids yielded potentially significant upfront capital equipment cost reductions by allowing the use of smaller pipes, pumps, heat exchangers, and storage tanks as well as reductions in operational costs. This report presents the first-phase results of assessment of impact of the advanced fluids on DHC systems. Future reports will focus on assessment of impact on hardware performance, capital eqiupment, and operation costs. 9 refs., 30 figs., 2 tab.

  3. District heating and cooling for the city and port of Tacoma: Phase 1, Feasibility study

    SciTech Connect

    Bloomquist, R.G.; Simpson, S.J.

    1988-01-05

    Expansion and up grade of Tacoma's largest sewage treatment facility together with a proposed biomass cogeneration plant sparked the interest of Washington State Energy Office (WSEO) to look at the district heating and cooling (DHC) potential. Sewage effluent is used in several Swedish cities as a heat source in heat pump assisted district heating systems. The treament facility is located adjacent to downtown and the new effluent transfer pipline will run through the port district in route to the Commencement Bay. Other potential heat sources are the proposed biomass cogeneration plant and Simpson Tacoma Kraft Pulp and Paper Mill. The pulp mill is also adjacent to downtown, however, the proposed cogeneration plant will be about a mile away. A preliminary district heating analysis was performed using a computer analysis tool called HEATPLAN. The analysis was favorable and a decision to move ahead with further study was made by WSEO.

  4. Feasibility of energy recovery for district heating and cooling from the METRO Renton effluent transfer system: Phase one report

    SciTech Connect

    Not Available

    1985-08-01

    The Municipality of Metropolitan Seattle (Metro) is constructing an effluent transfer system (ETS) from its Renton treatment plant through Seattle's largest industrial area to Duwamish Head. Preliminary evaluation indicates that heat pumps could produce between 500 and 800 million Btu per hour if all of the Renton plant's current flows were utilized. The market for district heating and coolign near the ETS route was divided into five study areas for purposes of Phase 1 work as follows: Sea-Tac International Airport; Tukwila/Renton; Metro South Base and Vicinity; Pacific Highway/Spokane Street; and Spokane Street/Kingdome. In each of these areas heating and cooling demands were inventoried, and preliminary concepts for district heating and cooling service were prepared and subjected to economic assessment. Initial results are presented.

  5. New Orleans district cooling system

    SciTech Connect

    Not Available

    1990-03-15

    The purpose of this study is to investigate the economic and energy saving potential of ammonia refrigeration for district cooling, as an alternate to equipment using CFC refrigerants. In order to be able offer a refrigeration machine that is safe to install inside a building, and is both low in capital cost and reasonably efficient, manufacturers have resorted to high speed centrifugal compressors to move the refrigerant. These machines have very narrow requirements for refrigerants. These machines are utterly dependent upon the particular CFC refrigerants that are slated for phase out by the year 2000 if not sooner. While the chemical industry is hard at work on replacements, it is highly unlikely that they will be able to produce a chemical that can be used in existing equipment. The most promising replacement refrigerant requires major modifications to existing machines. As a result, there is a real need for alternate means of producing refrigeration for cooling buildings. Ammonia refrigeration is a well developed, energy efficient way to produce cooling, with little of the environmental problems of the CFC refrigerants. While safety considerations restrict the use of ammonia in buildings, there should be few such restrictions on a central plant. This study compares the capital and operating costs of a new central cooling plant, remote from the buildings cooled, with the energy costs of operating the present cooling systems. 27 refs., 26 figs.

  6. Assessment of the potential of using district heating and cooling systems in Newark, New Jersey. Phase I. District heating and cooling assessment program. Final report

    SciTech Connect

    Not Available

    1988-01-01

    Objectives included: thermal market identification and development; identification of potential heat sources; evaluation of potential transmission/distribution network configurations; conceptual design and analysis of central plant options; economic feasibility of developing and operating a DHC system; analysis of financing options; and identification of the legal, regulatory, and institutional issues. Technically, it was concluded that a DHC system is feasible for the central business district of Newark, however: (1) the system must offer cooling as well as heating; (2) the medium should be steam at 150 psi or higher, and (3) no adequately sized thermal plants are available for leasing. Economically, the project is considered feasible, but (a) boiler-only plants are not economic; (b) new cogeneration is uncertain; and (c) electric sales are needed as well as heating and chilled-water sales. System-wise, the preferred system should be based on refuse, which has the fewest hurdles and mostly tax-exempt financing.

  7. Minnesota Project: district heating and cooling through power plant retrofit and distribution network. Final report. Phase 1. [Minnesota Project

    SciTech Connect

    1980-01-01

    Appendices are presented for the Minnesota Project: District Heating and Cooling Through Power Plant Retrofit and Distribution Network. These are: SYNTHA results (SYNTHA II is a proprietary program of the SYNTHA Corporation); Market Survey Questionnaire: Environmental Review Procedures; Public Service Commission Regulation of District Heating; Energy Use Normalization Procedures; Power Plant Description; Letters of Commitment; Bond Opinion and Issuance; and Marvin Koeplin Letter, Chairman of Public Service Commission, Moorehead, Minnesota.

  8. District Heating and Cooling Technology Development Program: Phase 2, Investigation of reduced-cost heat-actuated desiccant cooling systems for DHC applications

    SciTech Connect

    Patch, K.D.; DiBella, F.A.; Becker, F.E.

    1992-02-01

    A detailed assessment has been completed of the use of desiccant-based customer-sited heat-actuated cooling for District Heating and Cooling (DHC) systems, showing that introduction of a reduced-cost desiccant cooling system would result in widespread market penetration. This program consisted of three principal components: a market study of existing and future reduced-cost liquid desiccant cooling (LDC) systems; an examination of the installed costs of these existing and reduced-cost LDC systems; and four detailed case studies. Both the installed cost and equivalent chilled water cost of existing large LDC systems were found to be quite competitive with district chilled water, while the high capital cost of small LDC systems made them more expensive than district chilled water. Potential total system sales in this existing large-scale LDC market are quite low, since most of the market for DHC space conditioning is in smaller equipment sizes. Cost savings realized from producing a reduced-cost LDC system would result in small LDC systems (sized well below 6,000 cfm) becoming competitive with the current range of district chilled water costs.

  9. Choice materials for district cooling

    SciTech Connect

    Bergman, J.

    1995-12-31

    Stockholm Energi is anxious to get suggestions on pipe designs for district cooling systems that will be built in the future. A lot of effort has been put into this area when designing their first system. Operation of this system started in May of this year. Even if the pipes chosen so far will provide a long life time to the pipe system, the company expects that in the future other designs will give the same result for less money. Exchange of practical experiences across the ocean should make smarter and happier operators on both shores. The pipes chosen by Stockholm Energi for putting in the ground and in rock tunnels are steel pipes preinsulated with polyurethane foam covered with polyethylene. Design for indoor like installation has been stainless steel pipes insulated on site by foam injected in a cover of aluminium. The author will be happy to exchange further details on your request.

  10. An assessment of district heating and cooling potential in Joliet, Illinois: Phase I technical and economic feasibility study, final report

    SciTech Connect

    Not Available

    1987-11-01

    A preliminary assessment of the technical and economic feasibility of a district heating and cooling (DHC) system serving a portion of Joliet, Illinois, has been completed. The basic system, which was designed to provide thermal and electrical energy services to the assessment area, was found to be economically feasible while providing energy services at prices that are less than or equal to current costs. The DHC assessment area included the following: the Downtown Business District; the newly-designated Heritage Business Park; and the Joliet Correctional Center. The Heritage Business Park is the site of a former steel wire and rod mill. Approximately one-third of the site is currently occupied by a rod mill operated by American Steel and Wire while the rest of the Park is essentially undeveloped. In late 1985, plans were formulated to redevelop the site into an industrial park for light industry, offices and research and development facilities. The installation of a DHC system over the next five to ten years would not only complement the redevelopment of the Downtown Business District that was recently begun, but would help to encourage the eventual development of the Heritage Business Park as well.

  11. Phase 1 feasibility study: district heating and cooling using wastewater effluent and sea water in Olympia, Washington

    SciTech Connect

    Not Available

    1986-01-01

    The feasibility of district heating and cooling (DHC) using low-temperature hydrothermal sources in conjunction with heat pumps has been assessed on a preliminary basis for downtown Olympia and the Capitol Campus. The conclusion is that DHC can provide thermal energy at approximately 75 to 85% of the lowest competing fuel cost in the community. Three potential hydrothermal sources for DHC were evaluated: treated wastewater effluent from the LOTT plant; surface water from Capitol Lake or Budd Inlet; and waste process water from the Olympia Brewery. LOTT effluent and Budd Inlet sea water were both found to be favorable sources, possessing heat pump output potentials far in excess of the service area's heating or cooling demands. Capitol Lake was found to be an unfavorable source because its maximum potential as a heat pump source falls below the service area's thermal demands. The Olympia Brewery was also eliminated because its waste heat was likewise insufficient to meet winter demands, and it requires a costly transmission pipeline to the service area. However, it should be noted that at some point in the future the Brewery could become a DHC customer if its large demand for conventionally-fueled process heat becomes too costly.

  12. District heating and cooling for the city of Olympia and the Washington State Capitol Campus: Phase 1 feasibility study

    SciTech Connect

    Bloomquist, R.G.; Simpson, S.J.

    1986-06-01

    A new secondary treatment plant is operating adjacent to downtown Olympia and only 18 blocks or 2 kilometers from the Washington State Capitol Campus. The feasibility was studied of a district heating and cooling (DHC) system which would utilize the effluent from the sewage treatment plant and/or other available hydrothermal resources. The proposed DHC system in Olympia would extract heat from the sewage effluent or other hydrothermal sources through the use of one or more large water-to-water heat pumps. Hot water from the heat pumps would, in turn, be distributed through a pipeline network to areas of downtown Olympia and the Capitol Campus. Individual buildings would connect to the system thus alleviating the need for a boiler, furnace, or other heating unit. The top rated scenario for downtown Olympia utilizes sewage effluent from a secondary treatment plant in conjunction with a large water source heat pump. Existing boilers at the Capitol Campus and new boilers, to be constructed near the heat pump, will provide peaking and back-up capabilities to the system. The heat pump plant will be located adjacent to the sewage treatment plant and will extract 15/sup 0/ to 20/sup 0/F from the treated effluent stream prior to its disposal in Budd Inlet. The DHC system could produce 10 to 25% savings over the fuels presently being used.

  13. District cooling in Stockholm using sea water

    SciTech Connect

    Fermbaeck, G.

    1995-12-31

    In May this year Stockholm Energi started supplying properties in central Stockholm with cooling for comfort and for various processes from its new district cooling system. The project is unique in that most of the cooling energy is produced using cold water from the Baltic Sea. The following article describes the system and provides a summary of the considerations that resulted in venturing to invest in sea-water cooling for such a large project. There is also a description of the hydrological conditions that made the system feasible in Stockholm and some speculations about the possibilities to use cooled sea water elsewhere in the world.

  14. Handbook of district heating and cooling models

    SciTech Connect

    Reisman, A.W.

    1985-05-01

    In response to recent renewed interest in district heating and cooling (DHC) in the United States, consultants, city planners, and engineering firms have begun to search for existing models which might help identify and analyze new DHC projects. The United States Department of Energy (DOE), aware of the need to inform potential users of the existence of the public domain models developed under DOE sponsorship, has provided funds to Brookhaven National Laboratory (BNL), Upton, New York to produce this Handbook. In addition, the International District Heating and Cooling Association (IDHCA) has agreed to print and distribute the Handbook under its auspices, thus ensuring a wide audience in the district heating and cooling industry. At IDHCA's suggestion, the scope of the Handbook was expanded to allow inclusion of proprietary as well as public domain models.

  15. District cooling technology characterization case study: Austin, Texas

    SciTech Connect

    Coughlan, R.T.; Andrews, J.W.; Piraino, M.; Strasser, J.J.

    1990-01-01

    This report describes the work performed under Part 2 of the project entitled District Heating and Cooling Market Potential and Penetration Study.'' The project's primary objective is to study the potential of conventional and innovative district heating and cooling (DHC) space conditioning systems in the United States, in particular, those areas with significant heating and cooling load requirements. Part 2 entitled Implementation and Application of the Conceptual Approach,'' employs the DHC characterization methodology, previously developed in the initial phase of the project, to compare the economic feasibility of selected DHC system types in a specific community. Task 1 of Part 2 explored a broad-brush'' DHC characterization study of a high-heating load location using Milwaukee, Wisconsin, as a case area. This report addresses the completion of Task 2 of Part 2 which examines the potential of a few selected DHC systems in Austin, Texas, whose climate indicates a large demand for cooling. The subject matter described in this report focuses on the study of some district cooling technologies in Austin using the DHC characterization computer model developed at BNL. The model was employed to compare the economic viability of selected DHC system types, particularly those involving the production of chilled water and slush ice from cogenerator waste heat. Thermal storage applications were also considered. The annualized delivered energy cost was taken as the economic figure-of-merit. 6 refs., 33 figs., 5 tabs.

  16. District heating, cooling and cogeneration. Technology assessment

    SciTech Connect

    1997-11-01

    District heating and cooling/cogeneration (DHC/C) is the distribution of thermal energy from a central facility to multiple end-users in the surrounding area. This assessment evaluates the benefits and costs of DHC/C with and without cogeneration, estimates the New York State potential, and recommends actions to increase DHC/C use in the State. Specific tasks include: (1) Reviewing DHC/C technologies; (2) Quantifying energy, environmental and economic benefits; (3) Estimating the potential for DHC/C development in New York State; (4) Evaluating the role of technology research and development; and (5) Recommending actions to increase DHC/C in New York State.

  17. Mission Bay district heating and cooling feasibility study

    SciTech Connect

    Not Available

    1990-11-01

    The project known as Mission Bay is currently one of the largest urban redevelopment projects in the nation. In the planning stages for over six years, the 300 acre site will ultimately support a new, high density, mixed use community containing as many as 8000 new housing units and 6.8 million square feet of commercial space. In 1987, the City's Public Utilities Commission, Bureau of Energy Conservation prepared energy design recommendations for the Mission Bay project. These recommendations became known as the Energy Plan for Mission Bay. One of the recommendations of the Energy Plan was that district heating and cooling be carefully examined for its energy efficiency and environmental benefits, and for its positive impact on the local economic development of the new Mission Bay community. This report presents the findings of both the work on district cooling funded by USDOE, and on the studies of district heating funded by PG E. These have been combined together to provide a comprehensive feasibility study on a centralized cooling and heating system for the Mission Bay development. In May 1989, the City of San Francisco and Pacific Gas and Electric Company distributed a Request for Qualifications for experienced engineering firms to assess the economic and technical feasibility of District Heating and Cooling (DHC) at Mission Bay. VBB Pacific Planners/Engineers/Economist was selected to perform this feasibility study. The objective of this study was to examine the viability of a DHC system for Phase I and II of Mission Bay's planned construction while allowing for future phased expansion to the remainder of the Mission Bay development. 36 refs., 19 figs., 17 tabs.

  18. District Heating and Cooling Technology Development Program: Phase 2, Investigation of reduced-cost heat-actuated desiccant cooling systems for DHC applications. Final report, August 20, 1990--January 1, 1992

    SciTech Connect

    Patch, K.D.; DiBella, F.A.; Becker, F.E.

    1992-02-01

    A detailed assessment has been completed of the use of desiccant-based customer-sited heat-actuated cooling for District Heating and Cooling (DHC) systems, showing that introduction of a reduced-cost desiccant cooling system would result in widespread market penetration. This program consisted of three principal components: a market study of existing and future reduced-cost liquid desiccant cooling (LDC) systems; an examination of the installed costs of these existing and reduced-cost LDC systems; and four detailed case studies. Both the installed cost and equivalent chilled water cost of existing large LDC systems were found to be quite competitive with district chilled water, while the high capital cost of small LDC systems made them more expensive than district chilled water. Potential total system sales in this existing large-scale LDC market are quite low, since most of the market for DHC space conditioning is in smaller equipment sizes. Cost savings realized from producing a reduced-cost LDC system would result in small LDC systems (sized well below 6,000 cfm) becoming competitive with the current range of district chilled water costs.

  19. District heating and cooling market assessment

    SciTech Connect

    Teotia, A.P.S.; Karvelas, D.E.; Daniels, E.J.; Anderson, J.L.

    1993-06-01

    For more than 10 years, the U.S. Department of Energy (DOE) has supported research on and development of district steam, hot-water, and chilled-water systems in the residential and commercial sectors. In 1991, DOE sponsored a research project at Argonne National Laboratory (ANL) to reestimate the national market for district heating and cooling (DHC) systems to the year 2010. ANL had previously developed a DHC market-penetration model and used it to project future market penetration. The first step in the project was to conduct a literature search to identify major data sources on historical DHC markets and any past studies on the future market potential of DHC systems. On the basis of an evaluation of the available data and methodologies for estimating market penetration of new technologies, it was concluded that ANL should develop a new econometric model for forecasting DHC markets. By using the 1989 DOE/Energy Information Administration Commercial Buildings Energy Consumption Surveys (CBECS) public-use-tape data, a model was estimated for steam, hot-water, and chilled-water demand in the buildings surveyed. The model provides estimates of building steam, hot-water, and chilled-water consumption and expenditures between now and the year 2010. The analysis shows that the total U.S. market for district steam, hot water, and chilled water could grow from 0.8 quadrillion British thermal units (quad) in 1989 to 1.0 quad by 2000 and 1.25 quad by 2010. The demand for chilled water could nearly double in the forecast period, and its share could approach one-third of the total DHC market. This model, and the results, should be of use to policymakers, researchers, and market participants involved in the planning and implementation of community-based, energy-conserving, and environmentally beneficial energy systems.

  20. Two-phase transpiration cooling

    NASA Astrophysics Data System (ADS)

    El-Masri, M. A.

    1982-04-01

    The history of cooling technologies for gas turbines is briefly considered. It is pointed out that two-phase transpiration cooling offers significant benefits. A major incentive to study two-phase transpiration cooling is the thermodynamic benefit if fuel could be used as the transpiration coolant. The heat transfer problem in a transpired wall is composed of two matched subproblems, including the internal heat transfer between the coolant and the porous wall and the interaction of the transpired stream with the external boundary layer. An analysis of two-phase transpiration cooling is conducted, taking into account a model physical description, governing equations, regimes and modes of operation, and the two-phase range. On the basis of the analysis, two-phase transpiration is identified as a potentially-powerful cooling scheme for gas turbines. Moderate blade temperatures may be maintained in very high temperature gas streams without separating the boundary layer or incurring large aerodynamic or cooling penalties.

  1. District heating and cooling technology development program: Phase 2, Investigation of reduced-cost heat-actuated, desiccant cooling systems for DHC applications; Quarterly report, August 20, 1990--November 24, 1990

    SciTech Connect

    Patch, K.D.; DiBella, F.A.; Becker, F.E.

    1990-01-01

    This is the first Quarterly Report for DOE Project Number FG01-90CE26603. The principal objective of this program is to perform a more detailed study aimed at producing lower-cost heat-actuated liquid desiccant cooling system for use with two-pipe District Heating (DH) systems. This quarterly report covers project work conducted from August 20, 1990 to November 24, 1990. The goals of the project have their basis in the desire to lower the operating temperature of the transport medium in a DH system, but still enable cooling via that transport medium. At this time a district heating and cooling (DHC) system must use a four-pipe heating and cooling delivery system -- two pipes for hot water supply and return and two pipes for chilled water supply and return if both heating and cooling are to be provided. Unfortunately, such a four-pipe system is expensive, especially for existing DH systems that already have a two-pipe system installed.

  2. District heating and cooling systems for communities through power plant retrofit distribution network. Phase 2. Final report, 1 March 1980-31 January 1984

    SciTech Connect

    Not Available

    1984-01-01

    The potential for district heating was examined in terms of a total (regional) system and two subsystems of overlapping scales. The basis of the economic analysis of district heating was that the utility's electric and gas customers would not be economically burdened by the implementation of district heating, and that any incremental costs due to district heating (e.g. district heating capital and operating costs, replacement electric power, abandonment of unamortized gas mains) would be charged to district heating customers.

  3. District heating and cooling technology selection and characterization. Final report

    SciTech Connect

    Metz, P.D.; Catan, M.; Piraino, M.; Timmerman, R.W.; Gleason, J.

    1986-03-01

    This report describes the district heating and cooling (DHC) technology selection and characterization tasks performed under Part I of the project ''District Heating and Cooling Market Potential and Penetration Study'' for the USDOE. The purpose of this project is to determine the applicability of various DHC technologies to different community types and regions of the country. The results will be used by DOE to guide R and D program planning.

  4. The feasibility and economics of slush ice district cooling systems

    SciTech Connect

    Metz, P.; Margen, P.

    1987-06-01

    District cooling systems offer advantages over individual building systems by allowing the selection of central sites close to rivers or other low summer temperature heat sinks, sites close to open spaces for cool storage, and the advantage of reducing specific chiller and cool storage costs by economy of scale. These advantages are obtained at the penalty of the cost of an additional distribution system. This paper examines the technology status of slush ice district cooling systems. Then, using the BNL District Heating and Cooling (DHC) Technology Characterization Computer Model with delivered energy cost as the figure of merit, a wide range of central and individual building cooling systems are compared. Slush ice district systems are found to be most competitive with sharply-peaked cooling loads, premium piping installation costs, premium storage cost, and high on-peak electric rates. Research and development needs include an efficient low-cost reliable ice-making evaporator, an efficient heat-activated ice-making chiller, greater slush ice storage experience, and flow research -- particularly concerning frictional factors and segregation behavior.

  5. Cogeneration, district heating and district cooling: A century of district energy in Indianapolis

    SciTech Connect

    Pierce, M.A.

    1995-09-01

    In 1888, the proprietors of the Grand Opera House in Indianapolis requested electric light and steam heating service from the new Marmon-Perry Lighting Company, which the following year installed a small plant nearby to light several buildings and also heat the Opera House with exhaust steam piped through 250 feet of four-inch pipe. Indianapolis soon turned to natural gas for its heating needs, but the depletion of local gas fields at the turn of the century led to installation of several new low pressure steam and hot water district heating systems in the Indiana capital. These combined heat and power systems were finally merged together in 1927 to form Indianapolis Power and Light, which recently became a subsidiary of IPALCO Enterprises and is now the second-largest district energy utility in the United States. Mid-America Energy Resources, and unregulated subsidiary of IPALCO Enterprises formed in 1989, operates a 20,000 ton (70.4 mW) chilled water plant serving seventeen customers in downtown Indianapolis and also owns another district heating and cooling system serving downtown Cleveland.

  6. District cooling and heating development in Stamford, CT. Final report

    SciTech Connect

    1994-12-01

    This report summarizes the development options for introducing district cooling and heating in downtown Stamford, Connecticut. A district energy system as defined for the Stamford project is the production of chilled and hot water at a central energy plant, and its distribution underground to participating building in the vicinity. The objective of the study was to investigate implementation of a district energy system in conjunction with cogeneration as a means to encourage energy conservation and provide the city with an economic development tool. Analysis of the system configuration focused on selecting an arrangement which offered a realistic opportunity for implementation. Three main alternatives were investigated: (1) construction of an 82 MW cogeneration plant and a district heating and cooling system to serve downtown buildings, (2) construction of a small (4 MW) in-fence cogeneration plant combined with cooling and heating, and (3) construction of a district cooling and heating plant to supply selected buildings. Option (1) was determined to be unfeasible at this time due to low electricity prices. The analysis demonstrated that alternatives (2) and (3) were feasible. A number of recommendations are made for detailed cost estimates and ownership, leasing, and financial issues. 12 figs., 10 tabs.

  7. 1992 National census for district heating, cooling and cogeneration

    SciTech Connect

    Not Available

    1993-07-01

    District energy systems are a major part of the energy use and delivery infrastructure of the United States. With nearly 6,000 operating systems currently in place, district energy represents approximately 800 billion BTU per hour of installed thermal production capacity, and provides over 1.1 quadrillion BTU of energy annually -- about 1.3% of all energy used in the US each year. Delivered through more that 20,000 miles of pipe, this energy is used to heat and cool almost 12 billion square feet of enclosed space in buildings that serve a diverse range of office, education, health care, military, industrial and residential needs. This Census is intended to provide a better understanding of the character and extent of district heating, cooling and cogeneration in the United States. It defines a district energy system as: Any system that provides thermal energy (steam, hot water, or chilled water) for space heating, space cooling, or process uses from a central plant, and that distributes the energy to two or more buildings through a network of pipes. If electricity is produced, the system is a cogenerating facility. The Census was conducted through surveys administered to the memberships of eleven national associations and agencies that collectively represent the great majority of the nation`s district energy system operators. Responses received from these surveys account for about 11% of all district systems in the United States. Data in this report is organized and presented within six user sectors selected to illustrate the significance of district energy in institutional, community and utility settings. Projections estimate the full extent of district energy systems in each sector.

  8. District heating and cooling systems for communities through power plant retrofit distribution network. Phase 2. Final report, March 1, 1980-January 31, 1984. Volume IV

    SciTech Connect

    Not Available

    1984-01-31

    This volume contains the following: discussion of cost estimating methodology, detailed cost estimates of Hudson No. 2 retrofit, intermediate thermal plant (Kearny No. 12) and local heater plants; transmission and distribution cost estimate; landfill gas cost estimate; staged development scenarios; economic evaluation; fuel use impact; air quality impact; and alternatives to district heating.

  9. Feasibility study for district heating and cooling for the city of Des Moines, Iowa

    SciTech Connect

    Not Available

    1987-01-01

    District heating and cooling are technically feasible, with the Iowa Power Plant as a primary energy source with cogeneration and three types of distribution media: high and low temperature water for heating and chilled water for cooling. District heating is economically feasible, but additional studies are needed for cooling. In general, district cooling should be considered mainly in addition to heating, except perhaps for small systems. To be economically feasible, the large consumer/producers (Capitol Complex, Drake University, and the four hospitals) should be included, and a strong marketing effort conducted to induce a large portion of major downtown buildings to join the system. To help in marketing, piping connections and system conversions in the buildings or groups of buildings should be included in the overall construction project and its financing. Further consideration should be given to construct the metro refuse burning plant as an additional energy source for district heating and cooling, or to have this function take place at the Iowa Power Plant with fluidized-bed boilers. The large consumer/producers can reduce the peak load conditions and enjoy reduced interruptible rates. The Iowa Gas Company could be considered as an alternate energy source, with a downtown location for a DHC plant. The City of Des Moines should proceed with Phase II, Site Specific Feasibility Study, in accordance with the tentative plan submitted, and seek funding for it.

  10. District heating and cooling feasibility study, Dunkirk, New York

    SciTech Connect

    Not Available

    1988-06-01

    The objective of this project is to perform a preliminary investigation of the technical and economic feasibility of implementing a district heating and cooling (DHC) system in the City of Dunkirk, New York. The study was conducted by first defining a heating and cooling (HC) load service area. Then, questionnaires were sent to prospective DHC customers. After reviewing the owners responses, large consumers of energy were interviewed for more detail of their HC systems, including site visits, to determine possibilities of retrofitting their systems to district heating and cooling. Peak HC loads for the buildings were estimated by Burns and Roe's in-house computer programs. Based on the peak loads, certain customers were determined for suitability as anchor customers. Various options using cogeneration were investigated for possible HC sources. Equipment for HC sources and HC loads were sized and their associated costs estimated. Finally, economic analyses were performed. The conclusion is that it is technically and economically feasible to implement a district heating and cooling system in the City of Dunkirk. 14 figs., 15 tabs.

  11. Modular cogeneration in district heating and cooling systems

    SciTech Connect

    Andrews, J.W.; Aalto, P.; Gleason, T.C.J.; Skalafuris, A.J.

    1987-12-01

    The use of prepackaged cogeneration systems of modular size (100 kWe - 10 MWe) in conjunction with district heating and cooling is proposed as a way to enhance the energy conservation potential of both cogeneration and district energy systems. This report examines the technical and institutional aspects of this marriage of technologies, and develops a research agenda whose goal is to define this potential use of cogeneration more accurately and to develop the generic technology base needed to bring it to actuality. 11 refs.

  12. District heating and cooling systems for communities through power plant retrofit distribution network, Phase 2. Final report, March 1, 1980-January 31, 1984. Volume 5, Appendix A

    SciTech Connect

    Not Available

    1984-01-31

    This volume contains the backup data for the portion of the load and service assessment in Section 2, Volume II of this report. This includes: locations of industrial and commercial establishments, locations of high rise buildings, data from the Newark (Essex County) Directory of Business, data from the Hudson County Industrial Directory, data from the N. J. Department of Energy Inventory of Public Buildings, data on commercial and industrial establishments and new developments in the Hackensack Meadowlands, data on urban redevelopment and Operation Breakthrough, and list of streets in the potential district heating areas of Newark/Harrison and Jersey City/Hoboken.

  13. Oklahoma City explosion effect on the district heating & cooling system

    SciTech Connect

    DeJong, V.

    1995-09-01

    On April 19, 1995, in Oklahoma City, a bomb destroyed the Alfred P. Murrah Federal Office Building. The building was served by the Trigen-Oklahoma City Energy Corporation, a district heating and cooling (DHC) company. This paper describes the effect on the system and actions taken by personnel to restore heating and cooling to other customers. Associated with the bomb blast was a failure of the main electrical bus to the DHC plant. This occurred approximately 12 1/2 hours later. The effects of this event are also described.

  14. District cooling and thermal storage in pharmaceutical applications

    SciTech Connect

    Strause, R.; Morgan, T.

    1995-12-31

    Many of the guidelines for designing a central or district cooling plant can be applied to the pharmaceutical industry. Most pharmaceutical companies with central cooling plants have operated these plants very inefficiently for many years and these problems are now being addressed by the industry. The Clean Air Act and new tax guidelines have forced the pharmaceutical industry to address their utility costs. This paper will address some of the common problems faced by the industry and describe measures the industry has taken to correct them.

  15. Air conditioning with ammonia for district cooling

    SciTech Connect

    Toth, S.J. )

    1994-07-01

    This article describes a new system design incorporating 15 safety features which makes ammonia a viable choice for certain air-conditioning applications. CFC refrigerants will be phased out by the end of 1995 and will be replaced with environmentally friendly refrigerants. Because most air conditioning in the US is done with CFCs, a search for alternative refrigerants is now underway. Although ammonia (R-717) is perceived as an alternative refrigerant, it was actually the first refrigerant successfully used on a large scale in both the US and Europe, dating back to the 19th Century. Then and now, ammonia is one of the most efficient refrigerants for air conditioning, and it also offers zero ozone depleting potential and zero global warming potential.

  16. Steamtown District Heating and Cooling Project, Scranton, Pennsylvania. Final report

    SciTech Connect

    1990-04-01

    This report summarizes the activities of a study intended to examine the feasibility of a district heating and cooling alternative for the Steamtown National Historic Site in Scranton, PA. The objective of the study was to investigate the import of steam from the existing district heating system in Scranton which is operated by the Community Central Energy Corporation and through the use of modern technology provide hot and chilled water to Steamtown for its internal heating and cooling requirements. Such a project would benefit Steamtown by introducing a clean technology, eliminating on-site fuel use, avoiding first costs for central heating and cooling plants and reducing operation and maintenance expenditures. For operators of the existing district heating system, this project represents an opportunity to expand their customer base and demonstrate new technologies. The study was conducted by Joseph Technology Corporation, Inc. and performed for the Community Central Energy Corporation through a grant by the US Department of Energy. Steamtown was represented by the National Park Service, the developers of the site.

  17. District heating and cooling systems for communities through power plant retrofit distribution network, Phase 2. Final report, 1 March 1980-31 January 1984. Volume II

    SciTech Connect

    Not Available

    1984-01-31

    This volume begins with an Introduction summarizing the history, methodology and scope of the study, the project team members and the private and public groups consulted in the course of the study. The Load and Service Area Assessment follows, including: a compilation and analysis of existing statistical thermal load data from census data, industrial directories, PSE and G records and other sources; an analysis of responses to a detailed, 4-page thermal load questionnaire; data on public buildings and fuel and energy use provided by the New Jersey Dept. of Energy; and results of other customer surveys conducted by PSE and G. A discussion of institutional questions follows. The general topic of rates is then discussed, including a draft hypothetical Tariff for Thermal Services. Financial considerations are discussed including a report identifying alternative ownership/financing options for district heating systems and the tax implications of these options. Four of these options were then selected by PSE and G and a financial (cash-flow) analysis done (by the PSE and G System Planning Dept.) in comparison with a conventional heating alternative. Year-by-year cost of heat ($/10/sup 6/ Btu) was calculated and tabulated, and the various options compared.

  18. Downtown district cooling: A 21st century approach

    SciTech Connect

    1995-12-01

    On December 1, 1992, the Board of Directors of the Metropolitan Pier and Exposition Authority (MPEA) met on Chicago`s historic Navy Pier and ushered in a new era of competition for energy supply in Chicago. The MPEA, a state agency created for the purposes of promoting and operating fair and exposition facilities within the Chicago area (including the McCormick Place exposition center and Navy Pier), voted to accept a third-party proposal to provide district heating and cooling services to the existing McCormick Place facilities and a million square feet of new exposition space. The winning bidder was a joint venture between Trigen Energy, the nation`s largest provider of district energy services, and Peoples Gas, the gas distribution company which serves Chicago. This vote culminated two years of effort by the Energy Division of Chicago`s Department of Environment to analyze the feasibility and promote the implementation of a district energy system to serve the expanded McCormick Place and its environs in the South Loop neighborhood. Initial services began in November, 1993, with a new hot and cold water piping system interconnecting the three existing exhibition facilities. The final buildout of the system, with a combined peak demand predicted at 160 MMBtu of heating and 15,920 tons of and cooling, is scheduled for completion in the summer of 1997.

  19. Optimal energy transmission fluids for district heating and cooling applications

    SciTech Connect

    Kasza, K.E.; Choi, U.S.; Kaminsky, J.

    1987-05-01

    The US Department of Energy is sponsoring the development of improving energy transmission fluids for district heating and cooling applications. This long-range-program has as its objectives: (1) identifying and developing high performance thermal-hydraulic energy transmission fluids and the components to best utilize the fluids in DHC systems; (2) demonstrating that these fluids substantially reduce frictional losses and improve heat transfer, resulting in the ability to use smaller piping, pumps, heat exchangers, and storage tanks; and (3) generating friction and heat transfer correlations and system performance information needed for design of improved DHC systems.

  20. District heating/cooling assessment for Richmond, Indiana. Final report

    SciTech Connect

    Not Available

    1982-09-14

    The potential for one or more district heating and cooling systems in the City of Richmond was assessed. Appropriate community energy suppliers and users are identified and government policy-makers and private concerns were educated as to the options available. Recommendations were made concerning the most technically and economically sound system alternatives. A time frame was suggested for project construction, ownership, and operating arrangements, and institutional and legal considerations, as well as potential benefits to the City of Richmond were identified. Three early-start projects were identified which have the potential for near-term DHC system development within the city. A plan of action is presented.

  1. Optimal energy transmission fluids for District Heating and Cooling applications

    SciTech Connect

    Kasza, K.E.; Choi, U.S.; Kaminsky, J.

    1986-06-01

    Argonne National Laboratory under sponsorship of the US DOE Office of Buildings and Community Systems has embarked upon a comprehensive program to develop high performance energy transmission fluids for use in district Heating and cooling (DHC) Systems. These fluids would substantially reduce flow frictional losses and enhance heat transfer. The fluids have been shown in system enhancement scoping studies conducted by ANL to yield potentially significant upfront capital equipment cost reductions by allowing the use of smaller pipes, pumps and heat exchangers as well as reductions in operational costs.

  2. District heating and cooling: Renewed interest in old concept

    SciTech Connect

    Elliott, T.

    1987-02-01

    District heating and cooling (DHC) systems are thermal energy networks that distribute hot water, chilled water, or steam through insulated pipes to serve commercial, residential, institutional, and industrial energy needs for space heating, space cooling, and industrial purposes. DHC systems permit energy, as distinguished from fuel, to be bought and sold as a commodity. This article points out that DHC does seem to be making a comeback in municipal or ''downtown'' applications. The comeback has been given impetus by the general resurgence of urban areas in recent years, many of them neglected since World War II, a neglect compounded by the flight of industry, capital, and people from cities to suburbs. Now municipal governments across the nation are working to check this urban decay and rejuvenate their inner cities and towns. In the process, they are discovering that DHC systems can be a powerful adjunct to their rebuilding programs, helping stimulate economic development, providing job opportunities, and establishing stable, affordable energy supplies.

  3. Development of district heating and cooling plant operation support system

    SciTech Connect

    Iwasaki, Yoshihiko; Kobayashi, Shuichirou; Nagaiwa, Akihiro; Yamada, Yukihiro

    1998-10-01

    In this paper, a district heating and cooling (DHC) plant operation support system and an on-line heat load prediction system are described. For DHC plants using electricity, it is desirable to use thermal storage to shift the electric power load from the daytime to nighttime. To do that, it is necessary to make a schedule of DHC plant operation based on hourly heat load predictions for the next day. The operation support system has two subsystems. The heat load prediction subsystem gives the hourly heat load predictions that are necessary for heat pump operation. This subsystem is used on-line. In the similar days selection subsystem, similar days are selected from past plant operation. This operation support system is used in a real DHC plant operation.

  4. District heating and cooling: a 28-city assessment

    SciTech Connect

    Meshenberg, M.J.

    1983-08-01

    Findings of a project that assessed the potential for construction of district heating and cooling (DHC) systems in 28 US cities are presented. The project sought to determine whether DHC could promote local community and economic development. In the preliminary assessment, 17 of the cities identified up to 23 projects that could be built within three to five years. Most of these projects would rely on nonscarce heat sources such as refuse or geothermal energy, and to improve financial feasibility, the majority would cogenerate electricity along with heat. Many would use existing power plants or industrial boilers to hold down capital costs. Overall, the projects could generate as amany as 24,000 jobs and retain $165 million that otherwise could leave the communities, thereby helping to stabilize local economies.

  5. Desiccant-based, heat-actuated cooling assessment for DHC (District Heating and Cooling) systems

    SciTech Connect

    Patch, K.D.; DiBella, F.A.; Becker, F.E.

    1990-07-01

    An assessment has been completed of the use of desiccant-based, heat-actuated cooling for District Heating and Cooling (DHC) systems, showing that such desiccant-based cooling (DBC) systems are generally applicable to District Heating (DH) systems. Since the DH system only has to supply hot water (or steam) to its customers, systems that were designed as conventional two-pipe DH systems can now be operated as DHC systems without major additional capital expense. Desiccant-based DHC systems can be operated with low-grade DH-supplied heat, at temperatures below 180{degree}F, without significant loss in operating capacity, relative to absorption chillers. During this assessment, a systems analysis was performed, an experimental investigation was conducted, developmental requirements for commercializing DBC systems were examined, and two case studies were conducted. As a result of the case studies, it was found that the operating cost of a DBC system was competitive with or lower than the cost of purchasing DHC-supplied chilled water. However, because of the limited production volume and the current high capital costs of desiccant systems, the payback period is relatively long. In this regard, through the substitution of low-cost components specifically engineered for low-temperature DHC systems, the capital costs should be significantly reduced and overall economics made attractive to future users. 17 figs.

  6. District heating and cooling technology transfer program: Final report

    SciTech Connect

    Musselwhite, R.W.

    1989-03-10

    The purpose of this program was to transfer information and technology from cities developing or operating district heating and cooling (DHC) systems to those contemplating or starting development. Initially, two main activities were proposed by the Conference of Mayors Research and Education Foundation (COMREF) and accepted by DOE: (1) a survey of operating DHC systems and report on the findings; and (2) development of a peer-matching program involving local officials and others. However, before the proposal was approved by DOE, COMREF received support from another, non-DOE source to carry out a survey similar to the one that had been proposed. Therefore, commencement of work on the project was delayed while the scope of work was modified. The survey was replaced by preparation and publishing of a document to describe state programs that assist localities in developing DHC. The original project period was to have been March 24, 1987, through March 23, 1988. However, because of the necessity of modifying the scope of work, the period of performance was extended. The final end date was December 31, 1988.

  7. Assessment for the expansion of the Grand Rapids district heating and cooling system

    SciTech Connect

    Not Available

    1987-11-18

    New district heating and cooling areas are identified for Grand Rapids, Michigan. The district heating and cooling concept is assessed from the perspective of meeting economic development objectives through the application of cost effective expansion of the existing system. The assessment includes identification and characterization of potential service areas, supply options and distribution options, and specific potential district heating and cooling projects, and assesses their technical, economic, marketing, institutional and financial feasibility. The existing steam district heating system is reviewed, including an assessment of the potential for new customers in the existing service area. Two specific district heating and cooling customers in the existing service area. Two specific district heating and cooling projects are assessed. The development of a new hot water and chilled water system to serve a new East Bank Development is outlined, as well as the development of hot water system for the Heritage Hill area. A ten year expansion plan for developing the district heating and cooling system is described. (LEW)

  8. Characterization of selected application of biomass energy technologies and a solar district heating and cooling system

    SciTech Connect

    D'Alessio, Dr., Gregory J.; Blaunstein, Robert P.

    1980-09-01

    The following systems are discussed: energy self-sufficient farms, wood gasification, energy from high-yield silviculture farms, and solar district heating and cooling. System descriptions and environmental data are included for each one. (MHR)

  9. District heating and cooling in the United States: prospects and issues

    SciTech Connect

    Not Available

    1985-01-01

    This report concerns the operation of district heating and cooling (DHC) systems in the United States. Both urban and institutional systems are discussed. The history of DHC is reviewed along with the use of DHC in Europe. (BCS)

  10. Development of advanced low-temperature heat transfer fluids for district heating and cooling

    SciTech Connect

    Not Available

    1991-09-30

    The feasibility of adding phase change materials (PCMs) and surfactants to the heat transfer fluids in district cooling systems was investigated. It increases the thermal capacity of the heat transfer fluid and therefore decreases the volume that needs to be pumped. It also increases the heat transfer rate, resulting in smaller heat exchangers. The thermal behavior of two potential PCMs, hexadecane and tetradecane paraffin wax, was experimentally evaluated. The heat of fusion of these materials is approximately 60% of that of ice. They exhibit no supercooling and are stable under repeated thermal cycling. While test results for laboratory grade materials showed good agreement with data in the literature, both melting point and heat of fusion for commercial grade hexadecane were found to be considerably lower than literaturevalues. PCM/water mixtures were tested in a laboratory-scale test loop to determine heat transfer and flow resistance properties. When using PCMs in district cooling systems, clogging of frozen PCM particles isone of the major problems to be overcome. In the present project it is proposed to minimize or prevent clogging by the addition of an emulsifier. Effects of the emulsifier on the mixture of water and hexadecane(a PCM) were studied. As the amount of the emulsifier was increased, the size of the solid PCM particles became smaller. When the size of the particles was small enough, they did not stick together or stick to the cold surface of a heat exchanger. The amount of emulsifier to produce this condition was determined.

  11. Summary of district heating and cooling project in Moorhead, Minnesota

    SciTech Connect

    Kennedy, A.S.; Reddy, G.N.

    1984-09-01

    The project proposed was to retrofit the municipal power plant of the Moorhead Public Service Department (PSD) to function as a cogeneration plant providing the heat source for a medium-temperature (225/sup 0/F), hot-water DHC system. Development of the system would proceed in five stages, beginning with service to Moorhead State University and Concordia College in 1984. Expansion to the central business district and other commercial, residential, and industrial areas would proceed in subsequent phases, with the entire system scheduled to be completed in 1989. The thermal capacity of the DHC system proposed for Moorhead could reach 60 to 100 MW/sub t/ in six years. Furthermore, if the city of Fargo, North Dakota, which is located immediately across the Red River, were to join the system, thermal loads could grow to 200 MW/sub t/. Heat supplied from a refuse-fired municipal boiler facility is an attractive option for expanding the system to that scale, but was not considered within the scope of this study. The results of the Moorhead multiphase work program and the present status of project implementation are summarized herein.

  12. Feasibility study for district heating and cooling for the City of Des Moines, Iowa

    SciTech Connect

    Not Available

    1987-01-01

    The Des Moines District Heating and Cooling Assessment Study shows that: District heating and cooling are technically feasible, with the Iowa Power Plant as a primary energy source with cogeneration and three types of distribution media: high and low temperature water for heating and chilled water for cooling. District heating is economically feasible, but additional studies are needed for cooling. In general, district cooling should be considered mainly in addition to heating, except perhaps for small systems. To be economically feasible, the large consumer/producers (Capitol Complex, Drake University, and the four hospitals) should be included, and a strong marketing effort conducted to induce a large portion of major downtown buildings to join the system. To help in marketing, piping connections and system conversions in the buildings or groups of buildings should be included in the overall construction project and its financing. Further consideration should be given to construct the metro refuse burning plant as an additional energy source for district heating and cooling, or to have this function take place at the Iowa Power Plant with fluidized-bed boilers. The large consumer/producers can reduce the peak load conditions and enjoy reduced interruptible rates. The Iowa Gas Company could be considered as an alternate energy source, with a downtown location for a DHC plant.

  13. Reduction of pumping energy losses in district heating and cooling systems. Final report

    SciTech Connect

    Zakin, J.L.; Christensen, R.N.

    1992-10-01

    This project was designed to find effective surfactant friction reducing additives for use in district heating systems with temperatures of 50 to 90{degrees}C and effective additives fore district cooling systems with temperatures of 5 to 15{degrees}C. Heat transfer measurements in conventional shell and tube heat exchangers and in plate heat exchangers were also carried out to see how seriously these surfactant drag reducing additives reduce heat transfer coefficients.

  14. Reduction of pumping energy losses in district heating and cooling systems

    SciTech Connect

    Zakin, J.L.; Christensen, R.N.

    1992-10-01

    This project was designed to find effective surfactant friction reducing additives for use in district heating systems with temperatures of 50 to 90[degrees]C and effective additives fore district cooling systems with temperatures of 5 to 15[degrees]C. Heat transfer measurements in conventional shell and tube heat exchangers and in plate heat exchangers were also carried out to see how seriously these surfactant drag reducing additives reduce heat transfer coefficients.

  15. District Heating and Cooling Feasiblity Study, Salt Lake City, Utah: Final report

    SciTech Connect

    Not Available

    1988-09-09

    The following is a general description of the Burns and Roe study of District Heating and Cooling Feasibility for Salt Lake City, Utah. The study assesses District Heating and Cooling (DHC) and develops a conceptual district system for Salt Lake city. In assessing District Heating and Cooling in Salt Lake City, the system conceived is evaluated to determine whether it is technically and economically viable. To determine technical viability, aspects such as implementation, pipe routing, and environmental restrictions are reviewed to foresee any technical problems that would arise as a result of DHC. To determine economic feasibility, the conceived system is priced to determine the capital cost to construct, and modeled in an economic analysis using anticipated operating and fuel costs to produce the required revenue necessary to run the system. Technical and Economic feasibility are predicated on many variables, including heating and cooling load, pipe routing, system implementation, and fuel costs. These variables have been investigated and demonstrate a substantial potential for DHC in Salt Lake City. Areas of consideration include the Downtown Area, Metropolitan Hall of Justice and surrounding area, and the Hotel District.

  16. District Heating and Cooling feasibility study, Salt Lake City, Utah: Final report

    SciTech Connect

    Not Available

    1988-09-09

    The following is a general description of the Burns and Roe study of District Heating and Cooling Feasibility for Salt Lake City, Utah. The study assesses District Heating and Cooling (DHC) and develops a conceptual district system for Salt Lake City. In assessing District Heating and Cooling in Salt Lake City, the system conceived is evaluated to determine whether it is technically and economically viable. To determine technical viability, aspects such as implementation, pipe routing, and environmental restrictions are reviewed to foresee any technical problems that would arise as a result of DHC. To determine economic feasibility, the conceived system is priced to determine the capital cost to construct, and modeled in an economic analysis using anticipated operating and fuel costs to produce the required revenue necessary to run the system. Technical and Economic feasibility are predicated on many variables, including heating and cooling load, pipe routing, system implementation, and fuel costs. These variables have been investigated and demonstrate a substantial potential for DHC in Salt Lake City. Areas of consideration include the Downtown Area, Metropolitan Hall of Justice and surrounding area, and the Hotel District.

  17. District heating and cooling market potential and penetration methodology. Final report

    SciTech Connect

    Metz, P.D.; Gleason, J.

    1986-03-01

    This report describes the district heating and cooling (DHC) market potential and penetration methodology development tasks performed under Part I of the project ''District Heating and Cooling Market Potential and Penetration Study'' for the US DOE. Market potential and penetration methodologies were surveyed to identify those suitable for assessing the feasibility of DHC systems in the US, i.e., of translating the characteristics of each system to its market response. Each methodology was evaluated in terms of its level of detail, data requirements, costs, and other factors. A ''preferred'' methodology was developed, and a prognosis for implementing the preferred methodology was made.

  18. Geothermal district heating and cooling system for the city of Calistoga, California

    SciTech Connect

    Frederick, J.

    1982-01-01

    Calistoga has long been known for having moderate (270/sup 0/F maximum) hydrothermal deposits. The economic feasibility of a geothermal heating and cooling district for a portion of the downtown commercial area and city-owned building was studied. Descriptions of existing and proposed systems for each building in the block are presented. Heating and cooling loads for each building, retrofit costs, detailed cost estimates, system schematics, and energy consumption data for each building are included. (MHR)

  19. Development of advanced low-temperature heat transfer fluids for district heating and cooling, final report

    SciTech Connect

    Cho, Y.I.; Lorsch, H.G.

    1991-03-31

    The feasibility of adding phase change materials (PCMS) and surfactants to the heat transfer fluids in district cooling systems was investigated. It increases the thermal capacity of the heat transfer fluid and therefore decreases the volume that needs to be pumped. It also increases the heat transfer rate, resulting in smaller heat exchangers. The thermal behavior of two potential PCMS, hexadecane and tetradecane paraffin wax, was experimentally evaluated. The heat of fusion of these materials is approximately 60% of that of ice. They exhibit no supercooling and are stable under repeated thermal cycling. While test results for laboratory grade materials showed good agreement with data in the literature, both melting point and heat of fusion for commercial grade hexadecane were found to be considerably lower than literature values. PCM/water mixtures were tested in a laboratory-scale test loop to determine heat transfer and flow resistance properties. For 10% and 25% PCM/water slurries, the heat transfer enhancement was found to be approximately 18 and 30 percent above the value for water, respectively. Within the turbulent region, there is only a minor pumping penalty from the addition of up to 25% PCM to the water. Research is continuing on these fluids in order to determine their behavior in large-size loops and to arrive at optimum formulations.

  20. District cooling engineering & design program. Final technical report

    SciTech Connect

    Not Available

    1994-03-01

    Phoenix, Arizona is located in the Sonoran desert. Daytime temperatures typically rise to over 100 F during the three summer months. Average and peak temperatures have tended to rise over recent decades. This is generally attributed to what is known as the heat island effect, due to an increase in heat absorbing concrete and a decrease in irrigated farmland in the area. Phoenix is the eighth largest city in the US with a population of just over one million (1,000,000). The metropolitan area is one of the fastest growing in the nation. Over the last ten years its population has increased by over 40%. It is not an exaggeration to say the general availability of refrigerated air conditioning, both for buildings and automobiles has been an important factor enabling growth. The cost of operating public buildings has risen significantly in the last decade. In fiscal year 92/93 the City of Phoenix had energy expenses of over thirty four million dollars ($34,000,000). Because the City was planning a major new construction project, a new high-rise City Hall, it was decided to study and then optimize the design and selection of building systems to minimize long term owning and operating costs. The City Hall was to be constructed in downtown Phoenix. Phoenix presently owns other buildings in the area. A number of large cooling systems serving groups of buildings are currently operating in the Phoenix area. The City requested that the design consultants analyze the available options and present recommendations to the City`s engineering staff.

  1. Assessment of district heating/cooling potential in Holland, Michigan. Final report

    SciTech Connect

    Not Available

    1982-07-01

    A study undertaken to evaluate the potential for district heating/cooling (DHC) in the City of Holland, Michigan is documented. The purpose of the study was to assess the concept of delivering energy from a centralized source (or several sources) through a piping network to many end users for heating domestic hot water, space heating, space cooling and industrial process use. The Holland community was involved through representation of various businesses, agencies and community groups as part of an Assessment Work Group (AWG) membership. The AWG worked throughout the study with the BPW staff and consultants. Conclusions and recommendations of the study reflect the joint effort.

  2. District heating and cooling: a 28-city assessment. Technical and economic summary

    SciTech Connect

    Kennedy, A.S.; Tschanz, J.F.

    1983-02-01

    An overview is presented of information on the technical and economic characteristics of the most feasible district heating and cooling (DHC) projects selected by 25 of the 28 cities. The physical characteristics of potential service areas and associated energy demands to be supplied by the DHC systems are described. The technical aspects of the DHC system heat sources and supply networks are presented. The economics of the projects are discussed and energy consumption characteristics are listed. (MHR)

  3. Application of imitation steam'' systems to hot water district heating and cooling systems

    SciTech Connect

    Aalto, P.J.; Chen, D.B.

    1991-10-01

    Pequod Associates, Inc. and District Energy St. Paul, Inc. installed a pilot project of an innovative District Heating technology through a contract with the US DOE. This applied research was funded by the Energy Research and Development Act (94--163) for District Heating and Cooling Research. The experimental design is an intervention technique that permits hot water district heating systems to connect to buildings equipped with steam heating systems to connect to buildings equipped with steam heating systems. This method can substantially reduce conversion costs in many older buildings. The method circulates Imitation Steam, which is moist hot air, as a heating medium in standard steam radiators and steam heating coils. Based on the operation of the system during the 1989--90 and 1990--91 winter heating seasons, we conclude the following: the basic concept of using Imitation Steam was proved feasible. The performance of the system can be improved beyond the levels achieved in this installation. Imitation Steam did not cause significant corrosion in the piping system. The technology can be used by other district heating systems to lower conversion costs and increase market penetration. Among the additional benefits from this technology are: eliminating old, inefficient boilers; lower maintenance costs; improved fuel efficiency; reduced emissions.

  4. Emerging Two-Phase Cooling Technologies for Power Electronic Inverters

    SciTech Connect

    Hsu, J.S.

    2005-08-17

    In order to meet the Department of Energy's (DOE's) FreedomCAR and Vehicle Technologies (FVCT) goals for volume, weight, efficiency, reliability, and cost, the cooling of the power electronic devices, traction motors, and generators is critical. Currently the power electronic devices, traction motors, and generators in a hybrid electric vehicle (HEV) are primarily cooled by water-ethylene glycol (WEG) mixture. The cooling fluid operates as a single-phase coolant as the liquid phase of the WEG does not change to its vapor phase during the cooling process. In these single-phase systems, two cooling loops of WEG produce a low temperature (around 70 C) cooling loop for the power electronics and motor/generator, and higher temperature loop (around 105 C) for the internal combustion engine. There is another coolant option currently available in automobiles. It is possible to use the transmission oil as a coolant. The oil temperature exists at approximately 85 C which can be utilized to cool the power electronic and electrical devices. Because heat flux is proportional to the temperature difference between the device's hot surface and the coolant, a device that can tolerate higher temperatures enables the device to be smaller while dissipating the same amount of heat. Presently, new silicon carbide (SiC) devices and high temperature direct current (dc)-link capacitors, such as Teflon capacitors, are available but at significantly higher costs. Higher junction temperature (175 C) silicon (Si) dies are gradually emerging in the market, which will eventually help to lower hardware costs for cooling. The development of high-temperature devices is not the only way to reduce device size. Two-phase cooling that utilizes the vaporization of the liquid to dissipate heat is expected to be a very effective cooling method. Among two-phase cooling methods, different technologies such as spray, jet impingement, pool boiling and submersion, etc. are being developed. The Oak Ridge National Laboratory (ORNL) is leading the research on a novel floating refrigerant loop that cools high-power electronic devices and the motor/generator with very low cooling energy. The loop can be operated independently or attached to the air conditioning system of the vehicle to share the condenser and other mutually needed components. The ability to achieve low cooling energy in the floating loop is attributable to the liquid refrigerant operating at its hot saturated temperature (around 50 C+). In an air conditioning system, the liquid refrigerant is sub-cooled for producing cool air to the passenger compartment. The ORNL floating loop avoids the sub-cooling of the liquid refrigerant and saves significant cooling energy. It can raise the coefficient of performance (COP) more than 10 fold from that of the existing air-conditioning system, where the COP is the ratio of the cooled power and the input power for dissipating the cooled power. In order to thoroughly investigate emerging two-phase cooling technologies, ORNL subcontracted three university/companies to look into three leading two-phase cooling technologies. ORNL's assessments on these technologies are summarized in Section I. Detailed descriptions of the reports by the three university/companies (subcontractors) are in Section II.

  5. Techniques for preliminary market analysis in feasibility studies of district heating and cooling systems

    SciTech Connect

    Kron, N.F. Jr.

    1981-10-01

    A program aimed at increasing the application of district heating and cooling systems (DHCS) is described. It is believed that the energy and cost savings possible through using district heating and cooling (DHC) will stimulate creation of local jobs, reduce dependence on fuel imports, and spur activities for redevelopment or revitalization. Twenty-eight communities have received cooperative agreements to aid in a national assessment of DHCS feasibility. Preliminary market analysis for proposed DHC service areas would provide basic information on customer characteristics and their potential and desires to connect with a district system. This report explains a few of the common low-cost methods for rough-cut, preliminary market analysis, including a detailed look at a questionnaire method. The report is written for three groups of people: (1) individuals in the 28 communities who will need to collect market research data, (2) laboratory technical support personnel assigned to help explain research techniques, and (3) the community personnel who will be using the results of the market analysis to help them assess the feasibility of DHC applications in their communities.

  6. The Department of Energy District Heating and Cooling program: A decade (1982--1992) of accomplishments

    SciTech Connect

    Not Available

    1992-12-01

    District Heating and Cooling (DHC) systems have evolved over an extended period of time within a complex economic, political, social and technical community. Developers and customers from the public and private sectors have worked together, often in fragmented and piecemeal efforts, to develop new or improve old district heating and cooling systems. The US Department of Energy (DOE) works in partnership with industry and the utility sector to develop technological improvements for DHC systems. DOE also works with the Department of Housing and Urban Development (HUD), other federal agencies, state and local governments, universities, private industry, professional societies, trade as associations, and individuals to increase the market adoption rate of energy-efficient and cost-effective DHC systems. The current status report of activities includes on of projects such as the ice slurries field test effort to be completed in 1995/1996, planned by Argonne National Laboratory (ANL) in conjunction with Northern States Power and EPRI; and cost- studies in eight cities for detailed engineering and design of cooling systems scheduled to be completed in September, 1993. Several projects which are currently ongoing are: the DHC market potential estimation study that is being developed by ANL, the DHC/C study conducted by ORNL, and the DHC feasibility assessments to be performed in conjunction with the Georgia Tech University in connection with the 1996 Olympics in Atlanta.

  7. District heating and cooling in Provo, Utah. Volume 1. Strategy assessment

    SciTech Connect

    Kron, N.F. Jr.; Reddy, N.; Kennedy, A.S.; Dennis, C.B.

    1983-09-01

    Provo, Utah, is one of 28 cities selected by the US Department of Housing and Urban Development to participate in a study of the economic and community-development benefits of implementing a district heating and cooling (DHC) system. A number of DHC options for Provo were studied with the help of the Argonne District Heating Strategy Model. The model was used to analyze demand configuration and supply options. Two economically acceptable DHC systems were recommended for further study in Provo; one is a cogeneration system based on the city's power plant and the other is a noncogeneration system with heat supplied by the heating plant at Brigham Young University, which is located in Provo.

  8. Reduction of pumping energy losses in district heating and cooling systems

    SciTech Connect

    Zakin, J.L.

    1991-12-01

    This project was designed to explore the effects of different structures of cationic surfactant drag reducing additives on their efficiency and on their effective temperature ranges. The goal was to develop surfactant systems that would be useful in the appropriate temperature ranges for district heating systems (50--110{degree}C) and for district cooling systems (2--20{degree}C). To this end the chemical compositions of quaternary annonium salts and of counter-ions were varied. More than twenty different commercial or semi commercial quarterly ammonium salts from US suppliers and two from a German supplier (Hoechst) were tested along with thirty five different counter-ions. In addition, blends of several of each were also tested. A further object of this project was to check the compatibility of surfactant drag reducers with commercial or semi-commercial corrosion inhibitors in regard to maintaining their drag reducing ability and corrosion inhibiting capability.

  9. Reduction of pumping energy losses in district heating and cooling systems. Final report

    SciTech Connect

    Zakin, J.L.

    1991-12-01

    This project was designed to explore the effects of different structures of cationic surfactant drag reducing additives on their efficiency and on their effective temperature ranges. The goal was to develop surfactant systems that would be useful in the appropriate temperature ranges for district heating systems (50--110{degree}C) and for district cooling systems (2--20{degree}C). To this end the chemical compositions of quaternary annonium salts and of counter-ions were varied. More than twenty different commercial or semi commercial quarterly ammonium salts from US suppliers and two from a German supplier (Hoechst) were tested along with thirty five different counter-ions. In addition, blends of several of each were also tested. A further object of this project was to check the compatibility of surfactant drag reducers with commercial or semi-commercial corrosion inhibitors in regard to maintaining their drag reducing ability and corrosion inhibiting capability.

  10. District heating and cooling in Provo, Utah. Volume 2. Supplemental data for early options studied

    SciTech Connect

    Kron, N.F. Jr.; Reddy, N.; Kennedy, A.S.; Dennis, C.B.

    1983-09-01

    Provo, Utah, is one of 28 cities selected by the US Department of Housing and Urban Development to participate in a study of the economic and community-development benefits of implementing a district heating and cooling (DHC) system. A number of DHC options for Provo were studied, and the most promising and illustrative of these were described in Volume 1 of this report. This supplemental report provides information on several other options that were under consideration early in the Provo study. These options were subsequently found to be economically poor performers compared to the systems recommended in Volume 1.

  11. Assessment of district heating/cooling potential for the Frenchman's Cove redevelopment project. Final report

    SciTech Connect

    Not Available

    1982-10-01

    A study undertaken to evaluate the potential for district heating/cooling (DHC) in the City of Ecorse, Michigan is documented. the purpose of the study was to assess the concept of delivering energy from a centralized source (or several sources) through a piping network to many end users for heating domestic (tap) hot water, space heating, and space cooling. The primary focus of the study was the proposed redevelopment of eighty acres in Ecorse along the Detroit River waterfront known as Frenchman's Cove. As planned, the complete development would place nearly 2 million square feet of new, mixed use structures/facilities on the site and an eighteen acre undeveloped island located 300 feet offshore. Other areas of the city were also examined to identify and evaluate existing supply and end use possibilities. In addition, several neighboring communities were examined to determine the feasibility of downriver DHC network. Six large thermal energy producers identified in the study area include the Detroit Edison River Rouge power plant (DECo.-RR), the Wyandotte Municipal Services Commission (WMSC) power plant, a BASF/Wyandotte Corporation plant, a Marathon Oil refinery, the Great Lakes Steel complex, and the E.C. Levy Company slag processing site. Each was examined for potential as a thermal supplier on a district heating network.

  12. District heating and cooling assessment for the city of Ogden, Utah: Final report

    SciTech Connect

    Not Available

    1986-10-01

    District heating and cooling (DHC) is the process of supplying thermal energy in the form of hot water, steam, or chilled water from one or more central plants through a pipe distribution network to multiple customers. The thermal energy is used by the customers for space and water heating, space cooling, or industrial process requirements. During the past several decades the technologies and development of district heating systems have been relegated to providing steam to industries, university campuses, and military installations. There are also aging steam systems supplying energy to central business districts in some of the larger urban centers, primarily in the Northeast and Midwest. Meanwhile, European cities have developed modern and efficient systems using hot water serving entire cities. Since the 1972--1974 oil embargo, a better understanding of the role energy plays in urban areas has emerged. Ogden City has recognized this role and begun to identify methodologies and technologies that will allow the city to better manage its energy future. As part of the city's strategy, an Energy Task Force was established in 1981 by the Ogden City Council to study energy use in the community. A comprehensive energy plan developed by the Task Force was formally adopted by the Council in 1982 and made a part of the city's comprehensive plan. A twelve member Energy Commission was also established at this time to meet periodically and work toward implementing the goals of the plan on a community wide basis. A copy of the Energy Plan can be found as Appendix 1. 53 figs.

  13. MUON STORAGE RINGS FOR 6D PHASE SPACE COOLING.

    SciTech Connect

    KIRK,H.CLINE,D.FUKUI,Y.GARREN,A.

    2003-05-12

    We describe several storage ring designs for reducing the 6-dimensional phase space of circulating muon beams. These rings utilize quadrupole and dipole magnets as well as wedge-shaped, liquid-hydrogen, energy-loss absorbers and energy compensating rf cavities. We obtain evaluations of their cooling performance by particle tracking simulation. Such rings are potentially useful for future Neutrino Factories or Muon Colliders as well as for existing facilities in which cooled, intense muon beams could enhance their physics programs.

  14. Microwave link phase compensation for longitudinal stochastic cooling in RHIC

    SciTech Connect

    Mernick, K.; Blaskiewicz, M.; Brennan, J.M.; Johnson, B.; Severino, F.

    2010-05-02

    A new microwave link has been developed for the longitudinal stochastic cooling system, replacing the fiberoptic link used for the transmission of the beam signal from the pickup to the kicker. This new link reduces the pickup to kicker delay from 2/3 of a turn to 1/6 of a turn, which greatly improves the phase margin of the system and allows operation at higher frequencies. The microwave link also introduces phase modulation on the transmitted signal due to variations in the local oscillators and time of flight. A phase locked loop tracks a pilot tone generated at a frequency outside the bandwidth of the cooling system. Information from the PLL is used to calculate real-time corrections to the cooling system at a 10 kHz rate. The design of the pilot tone system is discussed and results from commissioning are described.

  15. Passive Two-Phase Cooling of Automotive Power Electronics: Preprint

    SciTech Connect

    Moreno, G.; Jeffers, J. R.; Narumanchi, S.; Bennion, K.

    2014-08-01

    Experiments were conducted to evaluate the use of a passive two-phase cooling strategy as a means of cooling automotive power electronics. The proposed cooling approach utilizes an indirect cooling configuration to alleviate some reliability concerns and to allow the use of conventional power modules. An inverter-scale proof-of-concept cooling system was fabricated, and tests were conducted using the refrigerants hydrofluoroolefin HFO-1234yf and hydrofluorocarbon HFC-245fa. Results demonstrated that the system can dissipate at least 3.5 kW of heat with 250 cm3 of HFC-245fa. An advanced evaporator design that incorporates features to improve performance and reduce size was conceived. Simulation results indicate its thermal resistance can be 37% to 48% lower than automotive dual side cooled power modules. Tests were also conducted to measure the thermal performance of two air-cooled condensers--plain and rifled finned tube designs. The results combined with some analysis were then used to estimate the required condenser size per operating conditions and maximum allowable system (i.e., vapor and liquid) temperatures.

  16. Phase space density as a measure of cooling performance for the international muon ionization cooling experiment

    SciTech Connect

    Berg, J. S.

    2015-05-03

    The International Muon Ionization Cooling Experiment (MICE) is an experiment to demonstrate ionization cooling of a muon beam in a beamline that shares characteristics with one that might be used for a muon collider or neutrino factory. I describe a way to quantify cooling performance by examining the phase space density of muons, and determining how much that density increases. This contrasts with the more common methods that rely on the covariance matrix and compute emittances from that. I discuss why a direct measure of phase space density might be preferable to a covariance matrix method. I apply this technique to an early proposal for the MICE final step beamline. I discuss how matching impacts the measured performance.

  17. Recent state legislation that encourages development of DHC (district heating and cooling) systems

    SciTech Connect

    Kier, P.H.; Meshenberg, M.L.

    1987-01-01

    While studying how state legislation affects the development of district heating and cooling (DHC) systems, research uncovered more than forty recently-enacted statutes in nearly thirty states that in some way encourage the development or operation of DHC systems. The content of these pieces of legislation indicates the variety of potential legal/regulatory problems that confront DHC systems and the legislative approaches to resolving those problems. These statutes do one or more of the following: exempt certain thermal energy producers or DHC systems from public utility regulation; provide for limited public utility regulation of some DHC systems; authorize state agencies to make loans to DHC systems or thermal energy producers; enable public entities to own DHC systems or thermal energy production facilities; or enable public entities to purchase from DHC systems. 1 tab.

  18. Assessment of district heating/cooling potential in Marquette, Michigan: Final report

    SciTech Connect

    Not Available

    1987-02-01

    A study of District Heating and Cooling was started in April 1985, and completed in February 1987. The study was funded by grants from the Department of Energy and the Michigan Energy Administration. A group of 14 individuals involved in local energy concerns served on the Assessment Work Group that provided basic data, review of consultant analyses and overall assessment of DHC opportunities in Marquette. Numerous DHC benefits were identified. 21 different scenarios of DHC were identified with variables of: thermal source, fuels to be used, distribution media, end users to be served, and cogeneration potential. The assessment of technical feasibility in Section 5 concludes that there is a substantial thermal load that could be supplied by central thermal distribution facilities which could displace more than 500,000 MCF equivalent of natural gas.

  19. Cooling compact stars and phase transitions in dense QCD

    NASA Astrophysics Data System (ADS)

    Sedrakian, Armen

    2016-03-01

    We report new simulations of cooling of compact stars containing quark cores and updated fits to the Cas A fast cooling data. Our model is built on the assumption that the transient behaviour of the star in Cas A is due to a phase transition within the dense QCD matter in the core of the star. Specifically, the fast cooling is attributed to an enhancement in the neutrino emission triggered by a transition from a fully gapped, two-flavor, red-green color-superconducting quark condensate to a superconducting crystalline or an alternative gapless, color-superconducting phase. The blue-colored condensate is modeled as a Bardeen-Cooper-Schrieffer (BCS)-type color superconductor with spin-one pairing order parameter. We study the sensitivity of the fits to the phase transition temperature, the pairing gap of blue quarks and the timescale characterizing the phase transition (the latter modelled in terms of a width parameter). Relative variations in these parameter around their best-fit values larger than 10-3 spoil the fit to the data. We confirm the previous finding that the cooling curves show significant variations as a function of compact star mass, which allows one to account for dispersion in the data on the surface temperatures of thermally emitting neutron stars.

  20. Cooling of Compact Stars with Color Superconducting Phase in Quark-hadron Mixed Phase

    NASA Astrophysics Data System (ADS)

    Noda, Tsuneo; Hashimoto, Masa-aki; Yasutake, Nobutoshi; Maruyama, Toshiki; Tatsumi, Toshitaka; Fujimoto, Masayuki

    2013-03-01

    We present a new scenario for the cooling of compact stars considering the central source of Cassiopeia A (Cas A). The Cas A observation shows that the central source is a compact star that has high effective temperature, and it is consistent with the cooling without exotic phases. The observation also gives the mass range of M >= 1.5 M ⊙, which may conflict with the current plausible cooling scenario of compact stars. There are some cooled compact stars such as Vela or 3C58, which can barely be explained by the minimal cooling scenario, which includes the neutrino emission by nucleon superfluidity (PBF). Therefore, we invoke the exotic cooling processes, where a heavier star cools faster than lighter one. However, the scenario seems to be inconsistent with the observation of Cas A. Therefore, we present a new cooling scenario to explain the observation of Cas A by constructing models that include a quark color superconducting (CSC) phase with a large energy gap; this phase appears at ultrahigh density regions and reduces neutrino emissivity. In our model, a compact star has a CSC quark core with a low neutrino emissivity surrounded by high emissivity region made by normal quarks. We present cooling curves obtained from the evolutionary calculations of compact stars: while heavier stars cool slowly, and lighter ones indicate the opposite tendency without considering nucleon superfluidity. Furthermore, we show that our scenario is consistent with the recent observations of the effective temperature of Cas A during the last 10 years, including nucleon superfluidity.

  1. Feasibility and Supply Analysis of U.S. Geothermal District Heating and Cooling System

    NASA Astrophysics Data System (ADS)

    He, Xiaoning

    Geothermal energy is a globally distributed sustainable energy with the advantages of a stable base load energy production with a high capacity factor and zero SOx, CO, and particulates emissions. It can provide a potential solution to the depletion of fossil fuels and air pollution problems. The geothermal district heating and cooling system is one of the most common applications of geothermal energy, and consists of geothermal wells to provide hot water from a fractured geothermal reservoir, a surface energy distribution system for hot water transmission, and heating/cooling facilities to provide water and space heating as well as air conditioning for residential and commercial buildings. To gain wider recognition for the geothermal district heating and cooling (GDHC) system, the potential to develop such a system was evaluated in the western United States, and in the state of West Virginia. The geothermal resources were categorized into identified hydrothermal resources, undiscovered hydrothermal resources, near hydrothermal enhanced geothermal system (EGS), and deep EGS. Reservoir characteristics of the first three categories were estimated individually, and their thermal potential calculated. A cost model for such a system was developed for technical performance and economic analysis at each geothermally active location. A supply curve for the system was then developed, establishing the quantity and the cost of potential geothermal energy which can be used for the GDHC system. A West Virginia University (WVU) case study was performed to compare the competiveness of a geothermal energy system to the current steam based system. An Aspen Plus model was created to simulate the year-round campus heating and cooling scenario. Five cases of varying water flow rates and temperatures were simulated to find the lowest levelized cost of heat (LCOH) for the WVU case study. The model was then used to derive a levelized cost of heat as a function of the population density at a constant geothermal gradient. By use of such functions in West Virginia at a census tract level, the most promising census tracts in WV for the development of geothermal district heating and cooling systems were mapped. This study is unique in that its purpose was to utilize supply analyses for the GDHC systems and determine an appropriate economic assessment of the viability and sustainability of the systems. It was found that the market energy demand, production temperature, and project lifetime have negative effects on the levelized cost, while the drilling cost, discount rate, and capital cost have positive effects on the levelized cost by sensitivity analysis. Moreover, increasing the energy demand is the most effective way to decrease the levelized cost. The derived levelized cost function shows that for EGS based systems, the population density has a strong negative effect on the LCOH at any geothermal gradient, while the gradient only has a negative effect on the LCOH at a low population density.

  2. Experimental investigation on phase change spray cooling with R22

    NASA Astrophysics Data System (ADS)

    Li, Mengjing; Liu, Jionghui; Liu, Xiufang; Hou, Yu

    2013-07-01

    Great quantities of experiments were performed to study the effects of two-phase spray cooling with high heat flux used R22 as refrigerant. A detailed research of the performance of spray cooling at different subcooling temperature was conducted. The experimental results show that the critical heat flux can reach 272.04Wṡcm-2 with R22 as the working medium, and the corresponding surface temperature is 21.11°C These figures prove that the spray cooling has the advantages of high heat flux as well as lower surface temperature. With increasing overcooling degree of refrigerant at the entrance of nozzle, CHF rises at first and goes to stable then. Which means the CHF can be developed by adding the overcooling of refrigerant. However, the development is limited to a certain degree according to the characteristics of the system; namely, the overmuch increment plays a little role to improve CHF value.

  3. Two-Phase Cooling Method Using R134a Refrigerant to Cool Power Electronic Devices

    SciTech Connect

    Lowe, Kirk T; Tolbert, Leon M; Ayers, Curtis William; Ozpineci, Burak; Campbell, Jeremy B

    2007-01-01

    This paper presents a two-phase cooling method using R134a refrigerant to dissipate the heat energy (loss) generated by power electronics (PE) such as those associated with rectifiers, converters, and inverters for a specific application in hybrid-electric vehicles (HEVs). The cooling method involves submerging PE devices in an R134a bath, which limits the junction temperature of PE devices while conserving weight and volume of the heat sink without sacrificing equipment reliability. First, experimental tests that included an extended soak for more than 300 days were performed on a submerged IGBT and gate-controller card to study dielectric characteristics, deterioration effects, and heat flux capability of R134a. Results from these tests illustrate that R134a has high dielectric characteristics, no deterioration on electrical components, and a heat flux of 114 W/cm 2 for the experimental configuration. Second, experimental tests that included simultaneous operation with a mock automotive air-conditioner (A/C) system were performed on the same IGBT and gate controller card. Data extrapolation from these tests determined that a typical automotive A/C system has more than sufficient cooling capacity to cool a typical 30 kW traction inverter. Last, a discussion and simulation of active cooling of the IGBT junction layer with R134a refrigerant is given. This technique will drastically increase the forward current ratings and reliability of the PE device

  4. Optimization of the engineering design for the Lansing District Cooling System by comparative analysis of the impact of advanced technologies on a conventional design approach. Volume 1

    SciTech Connect

    Not Available

    1994-02-01

    The Lansing Board of Water and Light (LBWL) began investigating development of a cooling district in the Lansing Downtown in 1989 in order to retain and build summer load for its steam utility. A feasibility study was conducted in conjunction with SFT, Inc. and ZBA, Inc. which addressed many factors such as marketability of the product, impact on the summer steam load, distribution system development, system design, probable capital and operating costs, reliability and environmental and other regulatory impacts on a preliminary feasibility basis. The Phase I study completed in September of 1989 provided highly promising results for establishing a District Cooling System (DCS). An existing chilled water production facility owned by the State of Michigan was identified as a potential location for a DCS plant. With these changes a review of the feasibility with a new set of alternatives and sensitivities was evaluated. This enhancement to the Phase I Study was nearing completion when the LBWL in conjunction with Energy, Mines and Resources Canada proposed to conduct the Phase II project in conjunction with DOE. The project was structured to proceed along a dual track to demonstrate the impact of the application of various innovative technologies.

  5. Thermal performance of phase change wallboard for residential cooling application

    SciTech Connect

    Feustel, H.E.; Stetiu, C.

    1997-04-01

    Cooling of residential California buildings contributes significantly to electrical consumption and peak power demand mainly due to very poor load factors in milder climates. Thermal mass can be utilized to reduce the peak-power demand, downsize the cooling systems, and/or switch to low-energy cooling sources. Large thermal storage devices have been used in the past to overcome the shortcomings of alternative cooling sources, or to avoid high demand charges. The manufacturing of phase change material (PCM) implemented in gypsum board, plaster or other wall-covering material, would permit the thermal storage to become part of the building structure. PCMs have two important advantages as storage media: they can offer an order-of-magnitude increase in thermal storage capacity, and their discharge is almost isothermal. This allows the storage of high amounts of energy without significantly changing the temperature of the room envelope. As heat storage takes place inside the building, where the loads occur, rather than externally, additional transport energy is not required. RADCOOL, a thermal building simulation program based on the finite difference approach, was used to numerically evaluate the latent storage performance of treated wallboard. Extended storage capacity obtained by using double PCM-wallboard is able to keep the room temperatures close to the upper comfort limits without using mechanical cooling. Simulation results for a living room with high internal loads and weather data for Sunnyvale, California, show significant reduction of room air temperature when heat can be stored in PCM-treated wallboards.

  6. The Analysis of A Hybrid Cooling System - Phase 2,

    NASA Astrophysics Data System (ADS)

    Yang, Kuan-Hsiung

    During the first phase of study, the mathematical modelling and the performance of the hybrid cooling system using solid desiccants were analyzed numerically. During this phase of study, the experimental investigation was conducted which yielded successful results with 5 % deviation as compared with the operational data of available commerical dehumidifiers. Furthmore, a prototype hybrid cooling system was actually constructed in the Refrigeration & Air-Conditioning Lab of National Sun Yat-Sen University (NSYSU), which generated good correlations with 7% deviation only, as compared with the analytical results. In other words, the good correlations obtained among the math modeling, the commercial unit operational data, and the NSYSU prototype system warrant the potential applications of this system for many industrial dehumidification and drying processes.

  7. State and local regulation of district-heating-and-cooling systems: issues and options

    SciTech Connect

    Kier, P.; Feit, J.; Hanselman, W.; Loube, R.; Meek, C.; Wilson, W.

    1981-11-01

    Basic questions pertaining to public regulation of district heating and cooling (DHC) systems are investigated. Any such system not completely contained within a single tract of privately owned land, or which makes retail sales of thermal energy, may be subject to the same sort of state regulation that electric and gas utilities receive. Many states apply traditional utility regulation to DHC systems, especially those that are investor-owned. State regulation of an energy utility usually establishes pervasive control over the utility's basic activities: its entry into a market, construction (though usually not siting) of its facilities, its service rates and revenue requirements, the quantity and quality of service it provides, and the conditions under which service may be abandoned. Some states, however, take less traditional approaches to DHC regulation - including nonregulation, less regulation for DHC than for electric and gas companies, and DHC regulation on a case-by-case basis. These approaches are examined to determine how each affects the startup of new DHC systems, the revitalization of old systems, and development of both. The report also addresses a variety of possible ownership arrangements for a DHC system and its main subsystems, as well as a variety of cost-allocation procedures that can be employed by a company cogenerating electrical and thermal energy. Material appended to the report backgrounds DHC operations in several European countries and presents US case law and recent state legislation pertaining to DHC regulation. The authors view district heating as a socially useful technology that can reduce US consumption of scarce and imported fuels, and they argue in general that appropriate DHC regulation is one means of helping the technology become established and expand. They recommend no specific regulatory approach, however; instead, they seek to clarify issues and present options on which decisions about DHC regulation can be based.

  8. Liouville`s theorem and phase-space cooling

    SciTech Connect

    Mills, R.L.; Sessler, A.M.

    1993-09-28

    A discussion is presented of Liouville`s theorem and its consequences for conservative dynamical systems. A formal proof of Liouville`s theorem is given. The Boltzmann equation is derived, and the collisionless Boltzmann equation is shown to be rigorously true for a continuous medium. The Fokker-Planck equation is derived. Discussion is given as to when the various equations are applicable and, in particular, under what circumstances phase space cooling may occur.

  9. COOLING OF COMPACT STARS WITH COLOR SUPERCONDUCTING PHASE IN QUARK-HADRON MIXED PHASE

    SciTech Connect

    Noda, Tsuneo; Hashimoto, Masa-aki; Yasutake, Nobutoshi; Maruyama, Toshiki; Tatsumi, Toshitaka; Fujimoto, Masayuki E-mail: hashimoto@phys.kyushu-u.ac.jp

    2013-03-01

    We present a new scenario for the cooling of compact stars considering the central source of Cassiopeia A (Cas A). The Cas A observation shows that the central source is a compact star that has high effective temperature, and it is consistent with the cooling without exotic phases. The observation also gives the mass range of M {>=} 1.5 M {sub Sun }, which may conflict with the current plausible cooling scenario of compact stars. There are some cooled compact stars such as Vela or 3C58, which can barely be explained by the minimal cooling scenario, which includes the neutrino emission by nucleon superfluidity (PBF). Therefore, we invoke the exotic cooling processes, where a heavier star cools faster than lighter one. However, the scenario seems to be inconsistent with the observation of Cas A. Therefore, we present a new cooling scenario to explain the observation of Cas A by constructing models that include a quark color superconducting (CSC) phase with a large energy gap; this phase appears at ultrahigh density regions and reduces neutrino emissivity. In our model, a compact star has a CSC quark core with a low neutrino emissivity surrounded by high emissivity region made by normal quarks. We present cooling curves obtained from the evolutionary calculations of compact stars: while heavier stars cool slowly, and lighter ones indicate the opposite tendency without considering nucleon superfluidity. Furthermore, we show that our scenario is consistent with the recent observations of the effective temperature of Cas A during the last 10 years, including nucleon superfluidity.

  10. State laws and regulations affecting development and renovation of district heating and cooling systems

    SciTech Connect

    Kier, P.H.; Meshenberg, M.J.

    1987-09-01

    This study of how state legislation affects development and renovation of district heating and cooling (DHC) systems has two focal points: for investor-owned systems, it examines public utility regulation, while for publicly owned systems, it looks at local government law. Statutes and case law were studied, and officials of several DHC systems were contacted, to identify problems imposed by the legal and regulatory framework and to learn how these problems can be resolved through changes in either the DHC systems or the statutes. Many private developers of DHC systems prefer to avoid regulation of their systems as public utilities and might be deterred by uncertainty as to whether they provide a regulated commodity and service to the public. Further, public-entity participation in DHC systems might be deterred in some states by lack of express statutory authority and by limitations on borrowing and on duration and types of contracts the systems can enter into. The study revealed 50 recent pieces of legislation that encourage or facilitate DHC systems (and that indicate problems and potential solutions). The content of this legislation was then used to construct drafts of two model statutes. The first - related to public utility regulation - adopts the limited-regulation approach of three western states in eliminating the most burdensome aspects of such regulation, including traditional rate regulation, while protecting customers. The second model statute - related to local government law - allows joint formation of DHC authorities by local government. 33 refs., 12 tabs.

  11. Reduction in air emissions attainable through implementation of district heating and cooling

    SciTech Connect

    Bloomquist, R.G.

    1996-12-31

    District heating and cooling (DHC) can provide multiple opportunities to reduce air emissions associated with space conditioning and electricity generation, which contribute 30% to 50% of all such emissions. When DHC is combined with cogeneration (CHP), maximum reductions in sulfur oxides (SO{sub x}), nitrogen oxides (NO{sub x}), carbon dioxide (CO{sub 2}), particulates, and ozone-depleting chlorofluorocarbon (CFC) refrigerants can most effectively be achieved. Although significant improvements in air quality have been documented in Europe and Scandinavia due to DHC and CHP implementation, accurately predicting such improvements has been difficult. Without acceptable quantification methods, regulatory bodies are reluctant to grant air emissions credits, and local community leaders are unwilling to invest in DHC and CHP as preferred methods of providing energy or strategies for air quality improvement. The recent development and release of a number of computer models designed specifically to provide quantification of air emissions that can result from DHC and CHP implementation should help provide local, state, and national policymakers with information vital to increasing support and investment in DHC development.

  12. The CERES S'COOL Project: Development and Operational Phases

    NASA Technical Reports Server (NTRS)

    Chambers, Lin H.; Young, David F.; Racel, Anne M.

    1998-01-01

    As part of NASA's Mission to Planet Earth, the first Clouds and the Earth's Radiant Energy System (CERES) instrument will be launched on the Tropical Rainfall Measuring Mission (TRMM) spacecraft from the Tanegashima launch site in Japan in November 1997. The instrument will measure the radiation budget incoming and outgoing radiant energy - of the Earth. The major feature of interest is clouds, which play a very strong role in regulating our climate. CERES will identify clear and cloudy regions and determine cloud physical and microphysical properties using imager data from a companion instrument. Validation efforts for the remote sensing algorithms will be intensive. As one component of the validation, the S'COOL (Students' Cloud Observations On-Line) project will involve school children around the globe in making ground truth measurements at the time of a CERES overpass. They will report cloud type, height, fraction, and opacity, as well as the local surface conditions. Their observations will be collected at the NASA Langley Distributed Active Archive Center (DAAC) and made available over the Internet for educational purposes as well as for use by the CERES Science Team in validation efforts. Pilot testing of the S'COOL project began in January 1997 with two local schools in Southeastern Virginia and one remote site in Montana. National testing in April 1997 involved 8 schools (grades 3 to high school) across the United States. Global testing will be carried out in October 1997. Details of the S'COOL project, which is mainly Internet-based, are being developed in each of these phases according to feedback received from participants. In 1998, when the CERES instrument is operational, a global observer network should be in place providing useful information to the scientists and learning opportunities to the students. Broad participation in the S'COOL project is planned, both to obtain data from a wide range of geographic areas, and to involve as many students as possible in learning about clouds and atmospheric science. This paper reports on the development phase of the S'COOL project, including the reaction of the teachers and students who have been involved. It describes the operational state of the S'COOL network, and identifies opportunities for additional participants.

  13. Feasibility of energy recovery for heat pump-assisted district heating and cooling from the Metro Renton wastewater treatment plant and effluent transfer system

    SciTech Connect

    Not Available

    1986-09-01

    The Municipality of Metropolitan Seattle (Metro) is constructing a 12-mile effluent transfer system (ETS) from its Renton wastewater treatment plant to Duwamish Head on Puget Sound. The preliminary stud (Phase I) concluded that the Renton treatment plant's effluent could feasibly sustain large amounts of heat pump output, i.e., 500 to 800 million Btu per hour. Further, the study identified eight locations along the ETS where district heating and cooling (DHC) networks could be favorably established to serve existing businesses and/or new growth. In December 1985 this second phase study was commissioned as a detailed assessment of specific customers in several of the recommended DHC development areas. The potential customers evaluated in this report include: Seattle-Tacoma International Airport, the Container Corporation carton manufacturing plant adjacent to the Renton treatment plant, Metro Transit Department's South Base, two buildings at the Boeing Developmental Center, and the Valley 405 Business Park adjacent to the Renton treatment plant. These potential users of effluent-based heating and/or cooling have been evaluated in terms of their heating and cooling demands, the type of effluent-based heat pump system necessary for serving them, and the economics of the effluent-based energy approach. In the cases of Sea-Tac and Container Corporation, the assessments also examine environmental and institutional issues, and generalized feasibilities for financing effluent-based systems.

  14. Development of advanced low-temperature heat transfer fluids for district heating and cooling. Final report, September 25, 1990--September 24, 1991

    SciTech Connect

    Not Available

    1991-09-30

    The feasibility of adding phase change materials (PCMs) and surfactants to the heat transfer fluids in district cooling systems was investigated. It increases the thermal capacity of the heat transfer fluid and therefore decreases the volume that needs to be pumped. It also increases the heat transfer rate, resulting in smaller heat exchangers. The thermal behavior of two potential PCMs, hexadecane and tetradecane paraffin wax, was experimentally evaluated. The heat of fusion of these materials is approximately 60% of that of ice. They exhibit no supercooling and are stable under repeated thermal cycling. While test results for laboratory grade materials showed good agreement with data in the literature, both melting point and heat of fusion for commercial grade hexadecane were found to be considerably lower than literaturevalues. PCM/water mixtures were tested in a laboratory-scale test loop to determine heat transfer and flow resistance properties. When using PCMs in district cooling systems, clogging of frozen PCM particles isone of the major problems to be overcome. In the present project it is proposed to minimize or prevent clogging by the addition of an emulsifier. Effects of the emulsifier on the mixture of water and hexadecane(a PCM) were studied. As the amount of the emulsifier was increased, the size of the solid PCM particles became smaller. When the size of the particles was small enough, they did not stick together or stick to the cold surface of a heat exchanger. The amount of emulsifier to produce this condition was determined.

  15. Schools and Neighborhoods Research Study: Phase Two--School District/City Relationships.

    ERIC Educational Resources Information Center

    Eismann, Donald; And Others

    The objectives of this phase, Phase 2, of the Schools and Neighborhoods Research Study were designed to yield research that would lead to action. The overall goal of improving communication and cooperation between the city, school district, and Seattle citizens was the basic consideration. The following were the objectives of this phase: to…

  16. User manual for AQUASTOR: a computer model for cost analysis of aquifer thermal energy storage coupled with district heating or cooling systems. Volume I. Main text

    SciTech Connect

    Huber, H.D.; Brown, D.R.; Reilly, R.W.

    1982-04-01

    A computer model called AQUASTOR was developed for calculating the cost of district heating (cooling) using thermal energy supplied by an aquifer thermal energy storage (ATES) system. The AQUASTOR model can simulate ATES district heating systems using stored hot water or ATES district cooling systems using stored chilled water. AQUASTOR simulates the complete ATES district heating (cooling) system, which consists of two principal parts: the ATES supply system and the district heating (cooling) distribution system. The supply system submodel calculates the life-cycle cost of thermal energy supplied to the distribution system by simulating the technical design and cash flows for the exploration, development, and operation of the ATES supply system. The distribution system submodel calculates the life-cycle cost of heat (chill) delivered by the distribution system to the end-users by simulating the technical design and cash flows for the construction and operation of the distribution system. The model combines the technical characteristics of the supply system and the technical characteristics of the distribution system with financial and tax conditions for the entities operating the two systems into one techno-economic model. This provides the flexibility to individually or collectively evaluate the impact of different economic and technical parameters, assumptions, and uncertainties on the cost of providing district heating (cooling) with an ATES system. This volume contains the main text, including introduction, program description, input data instruction, a description of the output, and Appendix H, which contains the indices for supply input parameters, distribution input parameters, and AQUASTOR subroutines.

  17. Legionnaires' disease bacteria in power plant cooling systems: Phase 2

    SciTech Connect

    Tyndall, R.L.; Christensen, S.W.; Solomon, J.A.

    1985-04-01

    Legionnaires' Disease Bacteria (Legionella) are a normal component of the aquatic community. The study investigated various environmental factors that affect Legionella profiles in power plant cooling waters. The results indicate that each of the four factors investigated (incubation temperature, water quality, the presence and type of associated biota, and the nature of the indigenous Legionella population) is important in determining the Legionella profile of these waters. Simple predictive relationships were not found. At incubation temperatures of 32/sup 0/ and 37/sup 0/C, waters from a power plant where infectious Legionella were not observed stimulated the growth of stock Legionella cultures more than did waters from plants where infectious Legionella were prevalent. This observation is consistent with Phase I results, which showed that densities of Legionella were frequently reduced in closed-cycle cooling systems despite the often higher infectivity of Legionella in closed-cycle waters. In contrast, water from power plants where infectious Legionella were prevalent supported the growth of indigenous Legionella pneumophila at 42/sup 0/C, while water from a power plant where infectious Legionella were absent did not support growth of indigenous Legionella. Some Legionella are able to withstand a water temperature of 85/sup 0/C for several hours, thus proving more tolerant than was previously realized. Finally, the observation that water from two power plants where infectious Legionella were prevalent usually supported the growth of Group A Legionella at 45/sup 0/C indicates the presence, of soluble Legionella growth promoters in these waters. This test system could allow for future identification and control of these growth promoters and, hence, of Legionella. 25 refs., 23 figs., 10 tabs.

  18. User manual for AQUASTOR: a computer model for cost analysis of aquifer thermal-energy storage oupled with district-heating or cooling systems. Volume II. Appendices

    SciTech Connect

    Huber, H.D.; Brown, D.R.; Reilly, R.W.

    1982-04-01

    A computer model called AQUASTOR was developed for calculating the cost of district heating (cooling) using thermal energy supplied by an aquifer thermal energy storage (ATES) system. the AQUASTOR Model can simulate ATES district heating systems using stored hot water or ATES district cooling systems using stored chilled water. AQUASTOR simulates the complete ATES district heating (cooling) system, which consists of two prinicpal parts: the ATES supply system and the district heating (cooling) distribution system. The supply system submodel calculates the life-cycle cost of thermal energy supplied to the distribution system by simulating the technical design and cash flows for the exploration, development, and operation of the ATES supply system. The distribution system submodel calculates the life-cycle cost of heat (chill) delivered by the distribution system to the end-users by simulating the technical design and cash flows for the construction and operation of the distribution system. The model combines the technical characteristics of the supply system and the technical characteristics of the distribution system with financial and tax conditions for the entities operating the two systems into one techno-economic model. This provides the flexibility to individually or collectively evaluate the impact of different economic and technical parameters, assumptions, and uncertainties on the cost of providing district heating (cooling) with an ATES system. This volume contains all the appendices, including supply and distribution system cost equations and models, descriptions of predefined residential districts, key equations for the cooling degree-hour methodology, a listing of the sample case output, and appendix H, which contains the indices for supply input parameters, distribution input parameters, and AQUASTOR subroutines.

  19. Offshore Floating Wind Turbine-driven Deep Sea Water Pumping for Combined Electrical Power and District Cooling

    NASA Astrophysics Data System (ADS)

    Sant, T.; Buhagiar, D.; Farrugia, R. N.

    2014-06-01

    A new concept utilising floating wind turbines to exploit the low temperatures of deep sea water for space cooling in buildings is presented. The approach is based on offshore hydraulic wind turbines pumping pressurised deep sea water to a centralised plant consisting of a hydro-electric power system coupled to a large-scale sea water-cooled air conditioning (AC) unit of an urban district cooling network. In order to investigate the potential advantages of this new concept over conventional technologies, a simplified model for performance simulation of a vapour compression AC unit was applied independently to three different systems, with the AC unit operating with (1) a constant flow of sea surface water, (2) a constant flow of sea water consisting of a mixture of surface sea water and deep sea water delivered by a single offshore hydraulic wind turbine and (3) an intermittent flow of deep sea water pumped by a single offshore hydraulic wind turbine. The analysis was based on one year of wind and ambient temperature data for the Central Mediterranean that is known for its deep waters, warm climate and relatively low wind speeds. The study confirmed that while the present concept is less efficient than conventional turbines utilising grid-connected electrical generators, a significant portion of the losses associated with the hydraulic transmission through the pipeline are offset by the extraction of cool deep sea water which reduces the electricity consumption of urban air-conditioning units.

  20. Method of cooling product gases of incomplete combustion containing ash and char which pass through a viscous, sticky phase

    SciTech Connect

    Koog, W.

    1984-08-21

    Hot gases containing ash and char which pass through an undesirable viscous, sticky phase on cooling through an intermediate temperature range, are cooled in a first cooling zone including a falling film of cooling liquid and a spray of cooling liquid followed by contact with a body of cooling liquid and subsequent mixing therewith.

  1. User manual for GEOCITY: a computer model for cost analysis of geothermal district-heating-and-cooling systems. Volume II. Appendices

    SciTech Connect

    Huber, H.D.; Fassbender, L.L.; Bloomster, C.H.

    1982-09-01

    The purpose of this model is to calculate the costs of residential space heating, space cooling, and sanitary water heating or process heating (cooling) using geothermal energy from a hydrothermal reservoir. The model can calculate geothermal heating and cooling costs for residential developments, a multi-district city, or a point demand such as an industrial factory or commercial building. Volume II contains all the appendices, including cost equations and models for the reservoir and fluid transmission system and the distribution system, descriptions of predefined residential district types for the distribution system, key equations for the cooling degree hour methodology, and a listing of the sample case output. Both volumes include the complete table of contents and lists of figures and tables. In addition, both volumes include the indices for the input parameters and subroutines defined in the user manual.

  2. Modeling Single-Phase and Boiling Liquid Jet Impingement Cooling in Power Electronics

    SciTech Connect

    Narumanchi, S. V. J.; Hassani, V.; Bharathan, D.

    2005-12-01

    Jet impingement has been an attractive cooling option in a number of industries over the past few decades. Over the past 15 years, jet impingement has been explored as a cooling option in microelectronics. Recently, interest has been expressed by the automotive industry in exploring jet impingement for cooling power electronics components. This technical report explores, from a modeling perspective, both single-phase and boiling jet impingement cooling in power electronics, primarily from a heat transfer viewpoint. The discussion is from the viewpoint of the cooling of IGBTs (insulated-gate bipolar transistors), which are found in hybrid automobile inverters.

  3. Proposed renovation of a district cooling plant to optimize the existing distribution system and increase production capacity

    SciTech Connect

    Tredinnick, S.M.

    1998-12-31

    The phaseout of chlorofluorocarbon (CFC) production in January 1996 is making district cooling (DC) an increasingly popular alternative to chiller retrofits and replacements. By connecting to a DC system, building owners and managers can focus on issues other than chilled-water production, thus liberating personnel, space, and financial resources for other important functions. A San Diego company has been serving the downtown business district of San Diego with reliable DC service since 1971. The existing system presently serves nine customers and, based on the current system plant pumping configuration, requires modifications in order to handle additional capacity. They are interested in signing on additional customers in the near future but cannot due to the limitations of the existing distribution system. This paper addresses modifications recommended to the company based on a hydraulic analysis and conceptual design completed in June 1995. The results of the analysis increased system distribution capacity from 5,245 tons (19.9 MW{sub th}) to almost 18,000 tons (62.9 MW{sub th}), while maintaining the present pipe system sizes. Investigations to increase plant capacity was not part of the scope of this paper since the focus was on the distribution system.

  4. An assessment of district heating and cooling alternatives with waste-to-energy co-generation potential on the east side of the City of Milwaukee

    SciTech Connect

    Tsao, K.C.; Swedish, M.J.; Kasun, D.J.; Bowser, B.A.

    1986-11-15

    This feasibility study covers the six significant components of any district heating and cooling (DHC) assessment project: (1) an analysis of thermal energy market potential; (2) an engineering analysis of thermal energy distribution system alternatives; (3) an engineering analysis of potential thermal energy generating sources; (4) an analysis of customer DHC system connection or hookup requirements; (5) project economics; and (6) institutional arrangements.

  5. MICE: The International Muon Ionization Cooling Experiment: Phase Space Cooling Measurement

    NASA Astrophysics Data System (ADS)

    Hart, T. L.

    2010-03-01

    MICE is an experimental demonstration of muon ionization cooling using a section of an ionization cooling channel and a muon beam. The muons are produced by the decay of pions from a target dipping into the ISIS proton beam at Rutherford Appleton Laboratory (RAL). The channel includes liquid-hydrogen absorbers providing transverse and longitudinal momentum loss and high-gradient radiofrequency (RF) cavities for longitudinal reacceleration, all packed into a solenoidal magnetic channel. MICE will reduce the beam transverse emittance by about 10% for muon momenta between 140 and 240 MeV/c. Time-of-flight (TOF) counters, threshold Cherenkov counters, and a calorimeter will identify background electrons and pions. Spectrometers before and after the cooling section will measure the beam transmission and input and output emittances with an absolute precision of 0.1%.

  6. MICE: The International Muon Ionization Cooling Experiment: Phase Space Cooling Measurement

    SciTech Connect

    Hart, T. L.

    2010-03-30

    MICE is an experimental demonstration of muon ionization cooling using a section of an ionization cooling channel and a muon beam. The muons are produced by the decay of pions from a target dipping into the ISIS proton beam at Rutherford Appleton Laboratory (RAL). The channel includes liquid-hydrogen absorbers providing transverse and longitudinal momentum loss and high-gradient radiofrequency (RF) cavities for longitudinal reacceleration, all packed into a solenoidal magnetic channel. MICE will reduce the beam transverse emittance by about 10% for muon momenta between 140 and 240 MeV/c. Time-of-flight (TOF) counters, threshold Cherenkov counters, and a calorimeter will identify background electrons and pions. Spectrometers before and after the cooling section will measure the beam transmission and input and output emittances with an absolute precision of 0.1%.

  7. Power plant retrofit to district heating and cooling projects and grid-connected integrated community energy systems projects. Program summary meeting, 1983

    SciTech Connect

    Kennedy, A.S.; Karvelas, D.E.

    1983-12-01

    Community projects were selected in two areas: (1) power plant retrofit to district heating and cooling (DHC) and (2) grid-connected integrated community energy systems (GC-ICES). In the first area, existing power plants were to be retrofitted to recover rejected heat, and thermal piping networks were to be planned and constructed to distribute the heat to the local community. In the second area, smaller-scale projects were to be designed and developed to meet the requirements for thermal energy service within the local community and to sell cogenerated electricity to the electric power grid. These projects proceeded through several phases of development toward the goals of completing construction and beginning operation. These phases were (I) assessment and conceptual design, (II) feasibility and preliminary design, (III) financing and final design, (IV) construction, and (V) start-up and operation. The results of the projects as presented at the program summary meeting held in May 1983 at Georgetown University in Washington, D.C. are summarized. In all, 12 projects are included, plus a report on the state implementation pilot plan in Minnesota and two panel discussion conducted at the meeting - one on resolving barriers to GS-ICES and DHC systems and the other on implementation issues. A summary of the major conclusions of this meeting is given.

  8. Effect of Continuous Cooling on Secondary Phase Precipitation in the Super Duplex Stainless Steel ZERON-100

    NASA Astrophysics Data System (ADS)

    Calliari, Irene; Bassani, Paola; Brunelli, Katya; Breda, Marco; Ramous, Emilio

    2013-12-01

    The precipitation of secondary phases in super duplex stainless steels (SDSS) is a subject of great relevance owing to their dangerous effects on both mechanical and corrosion-resistance properties. This paper examines the effect of continuous cooling after solution annealing treatment on secondary phase precipitation in the ZERON-100 SDSS. It considers the influence of cooling rate on volume fraction, morphology and chemical composition. It has been found that the formation of sigma and chi phases can be avoided only at cooling rates higher than 0.7 °C/s. In addition, at the lowest cooling rate the sigma phase amount approaches the equilibrium value, but the chi phase amount remains significantly low.

  9. Cooling of Compact Stars with Quark-Hadron Mixed Phase in the Colour Superconductive State

    SciTech Connect

    Noda, Tsuneo; Hashimoto, Masa-aki; Yasutake, Nobutoshi; Maruyama, Toshiki; Tatsumi, Toshitaka; Fujimoto, Masayuki

    2010-08-12

    Recently, the central source of Cassiopeia A (Cas A) has been observed, which indicates that the star has large mass and high effective temperature. We suspect that the compact object cools by the standard neutrino emission. We assume that the compact object contains quark matter with colour superconductivity and calculate cooling curves. Considering the Quark-Hadron Mixed Phase, we obtain cooling curves which are found to be consistent with the observations.

  10. Experimental investigation of single-phase microjet cooling of microelectronics

    NASA Astrophysics Data System (ADS)

    Rusowicz, Artur; Leszczyński, Maciej; Grzebielec, Andrzej; Laskowski, Rafał

    2015-09-01

    Development of electronics, which aims to improve the functionality of electronic devices, aims at increasing the packing of transistors in a chip and boosting clock speed (the number of elementary operations per second). While pursuing this objective, one encounters the growing problem of thermal nature. Each switching of the logic state at the elementary level of an integrated circuit is associated with the generation of heat. Due to a large number of transistors and high clock speeds, higher heat flux is emitted by the microprocessor to a level where the component needs to be intensively cooled, or otherwise it will become overheated. This paper presents the cooling of microelectronic components using microjets.

  11. Benefits of advanced working fluids for DHC (district heating and cooling) systems

    SciTech Connect

    Choi, U.S.; Kasza, K.E.

    1988-09-01

    DHC projects have positive economic and community development rewards. Today the US DHC industry has moved beyond a market consisting of institutional and military-base systems to community energy systems which cover the central business district and adjoining high density areas as well as communities that need revitalization and new development. One day DHC may be a national industry when DHC is married to electric utilities by recovering waste heat from nuclear or coal power plants (rather than wasting it causing thermal pollution) and supplying heat to customers through the DHC loop as is done in several European countries. These cogenerative DHC systems will make a significant impact on energy conservation and create the most reliable and efficient electric utility systems. The objectives of this paper, are to review the benefits and barriers of conventional DHC technology, introduce the concepts of advanced working fluids and consider the potential benefits of these advanced working fluids for DHC systems. 5 refs.

  12. Light-Weight, Single-Phase, Liquid-Cooled Cold Plate (Presentation)

    SciTech Connect

    Narumanchi, S.

    2013-07-01

    This presentation, 'Light-Weight, Low-Cost, Single-Phase Liquid-Cooled Cold Plate,' directly addresses program goals of increased power density, specific power, and lower cost of power electronics components through improved thermal management.

  13. Light-Weight, Low-Cost, Single-Phase, Liquid-Cooled Cold Plate (Presentation)

    SciTech Connect

    Narumanchi, S.

    2013-07-01

    This presentation, 'Light-Weight, Low-Cost, Single-Phase Liquid-Cooled Cold Plate,' directly addresses program goals of increased power density, specific power, and lower cost of power electronics components through improved thermal management.

  14. Environmental improvements resulting from the use of renewable energy sources and nonpolluting fuels and technologies with district heating and cooling

    SciTech Connect

    Kainlauri, E.O.

    1996-12-31

    The use of district heating and cooling (DHC) for a group of buildings or on a city-wide basis does by itself usually improve the local environmental conditions, regardless of the type of fuel used, as the DHC system replaces a larger number of individual units and is able to utilize anti-pollution and emission-cleaning devices at a central location. The DHC system may also be able to use several alternative choices for fuel, including renewable energy sources, depending on both economic and environmentally required conditions. The DHC systems are also safe and clean for the users, eliminating the need for fuel-burning equipment in their buildings. Solar energy is being utilized to a small degree in district heating systems, sometimes with the assistance of energy storage facilities, to reduce the amount of fuel needed to burn for the total system. The use of municipal and industrial waste as fuel helps reduce the amount of fossil fuel being burned and also reduces the areas of landfill needed to dispose wastes, but special care must be exercised to avoid releases of toxic gases into the atmosphere. This paper describes a few examples of the use of solar energy and energy storage in community-wide systems (Lyckebo in Sweden, Kerava in Finland), the use of natural gas in DHC (Lappenranta and Lahti in Finland), and applications of heat pump utilization in DHC (Uppsala wastewater and Stockholm preheat system in Sweden). Some projections are made of several alternative fuels derived from biomass, recycling, and other possible technologies in the future development of waste-handling and DHC systems. A brief discussion is included regarding the environmental concerns and legislative development in the US and elsewhere in the world.

  15. Abnormal correlation between phase transformation and cooling rate for pure metals

    NASA Astrophysics Data System (ADS)

    Han, J. J.; Wang, C. P.; Liu, X. J.; Wang, Y.; Liu, Z.-K.; Zhang, T.-Y.; Jiang, J. Z.

    2016-03-01

    This work aims to achieve deep insight into the phenomenon of phase transformation upon rapid cooling in metal systems and reveal the physical meaning of scatter in the time taken to reach crystallization. The total number of pure metals considered in this work accounts for 14. Taking pure copper as an example, the correlation between phase selection of crystal or glass and cooling rate was investigated using molecular dynamic simulations. The obtained results demonstrate that there exists a cooling rate region of 6.3 × 1011–16.6 × 1011 K/s, in which crystalline fractions largely fluctuate along with cooling rates. Glass transformation in this cooling rate region is determined by atomic structure fluctuation, which is controlled by thermodynamic factors. According to the feature of bond-orientation order at different cooling rates, we propose two mechanisms of glass formation: (i) kinetic retardation of atom rearrangement or structural relaxation at a high cooling rate; and (ii) competition of icosahedral order against crystal order near the critical cooling rate.

  16. Abnormal correlation between phase transformation and cooling rate for pure metals.

    PubMed

    Han, J J; Wang, C P; Liu, X J; Wang, Y; Liu, Z-K; Zhang, T-Y; Jiang, J Z

    2016-01-01

    This work aims to achieve deep insight into the phenomenon of phase transformation upon rapid cooling in metal systems and reveal the physical meaning of scatter in the time taken to reach crystallization. The total number of pure metals considered in this work accounts for 14. Taking pure copper as an example, the correlation between phase selection of crystal or glass and cooling rate was investigated using molecular dynamic simulations. The obtained results demonstrate that there exists a cooling rate region of 6.3 × 10(11)-16.6 × 10(11) K/s, in which crystalline fractions largely fluctuate along with cooling rates. Glass transformation in this cooling rate region is determined by atomic structure fluctuation, which is controlled by thermodynamic factors. According to the feature of bond-orientation order at different cooling rates, we propose two mechanisms of glass formation: (i) kinetic retardation of atom rearrangement or structural relaxation at a high cooling rate; and (ii) competition of icosahedral order against crystal order near the critical cooling rate. PMID:26939584

  17. Abnormal correlation between phase transformation and cooling rate for pure metals

    PubMed Central

    Han, J. J.; Wang, C. P.; Liu, X. J.; Wang, Y.; Liu, Z.-K.; Zhang, T.-Y.; Jiang, J. Z.

    2016-01-01

    This work aims to achieve deep insight into the phenomenon of phase transformation upon rapid cooling in metal systems and reveal the physical meaning of scatter in the time taken to reach crystallization. The total number of pure metals considered in this work accounts for 14. Taking pure copper as an example, the correlation between phase selection of crystal or glass and cooling rate was investigated using molecular dynamic simulations. The obtained results demonstrate that there exists a cooling rate region of 6.3 × 1011–16.6 × 1011 K/s, in which crystalline fractions largely fluctuate along with cooling rates. Glass transformation in this cooling rate region is determined by atomic structure fluctuation, which is controlled by thermodynamic factors. According to the feature of bond-orientation order at different cooling rates, we propose two mechanisms of glass formation: (i) kinetic retardation of atom rearrangement or structural relaxation at a high cooling rate; and (ii) competition of icosahedral order against crystal order near the critical cooling rate. PMID:26939584

  18. Estimating market penetration of new district heating and cooling systems using a combination of economic cost and diffusion models

    SciTech Connect

    Teotia, A.P.S.; Karvelas, D.E.

    1991-05-10

    The economic-cost model and the diffusion model are among the many market-penetration forecasting approaches that are available. These approaches have been used separately in many applications. In this paper, the authors briefly review these two approaches and then describe a methodology for forecasting market penetration using both approaches sequentially. This methodology is illustrated with the example of market-penetration forecasting of new district heating and cooling (DHC) systems in the Argonne DHC Market Penetration Model, which was developed and used over the period 1979--1983. This paper discusses how this combination approach, which incorporates the strengths of the economic-cost and diffusion models, has been superior to any one approach for market forecasts of DHC systems. Also discussed are the required modifications for revising and updating the model in order to generate new market-penetration forecasts for DHC systems. These modifications are required as a result of changes in DHC engineering, economic, and market data from 1983 to 1990. 13 refs., 5 figs., 2 tabs.

  19. A pumped two-phase cooling system for spacecraft

    NASA Technical Reports Server (NTRS)

    Ollendorf, S.; Costello, F. A.

    1983-01-01

    A pumped, two-phase heat-transport system is being developed for possible use for temperature control of scientific instruments on future NASA missions. As compared to a single-phase system, this two-phase system can maintain tighter temperature control with less pumping power. A laboratory model of the system has been built and tested. The measured heat transfer coefficients were approximately the same as in heat pipes, 220 Btu/hr-sq ft-F, as compared to 25 Btu/hr-sq ft-F for single-phase liquid flow. Heat shearing between experiments has been demonstrated wherein vapor generated in the cold plate of an active experiment was condensed in a cold, unheated experiment. System stability has been observed. However, additional development is needed. The use of non-azeotropic mixtures of coolants appears especially promising as a simple way to determine exit quality and thus control the flow rates to prevent dryout.

  20. CLOSURE OF HLW TANKS PHASE 2 FULL SCALE COOLING COILS GROUT FILL DEMONSTATIONS

    SciTech Connect

    Hansen, E; Alex Cozzi, A

    2008-06-19

    This report documents the Savannah River National Laboratory (SRNL) support for the Tank Closure and Technology Development (TCTD) group's strategy for closing high level radioactive waste (HLW) tanks at the Savannah River Site (SRS). Specifically, this task addresses the ability to successfully fill intact cooling coils, presently within the HLW tanks, with grout that satisfies the fresh and cured grout requirements [1] under simulated field conditions. The overall task was divided into two phases. The first phase was the development of a grout formulation that satisfies the processing requirements for filling the HLW tank cooling coils [5]. The second phase of the task, which is documented in this report, was the filling of full scale cooling coils under simulated field conditions using the grout formulation developed in the first phase. SRS Type I tank cooling coil assembly design drawings and pressure drop calculations were provided by the Liquid Waste (LW) customer to be used as the basis for configuring the test assemblies. The current concept for closing tanks equipped with internal cooling coils is to pump grout into the coils to inhibit pathways for infiltrating water. Access to the cooling coil assemblies is through the existing supply/return manifold headers located on top of the Type I tanks. The objectives for the second phase of the testing, as stated in the Task Technical and Quality Assurance plan (TTQAP) [2], were to: (1) Perform a demonstration test to assess cooling coil grout performance in simulated field conditions, and (2) Measure relevant properties of samples prepared under simulated field conditions. SRNL led the actual work of designing, fabricating and filling two full-scale cooling coil assemblies which were performed at Clemson Engineering Technologies Laboratory (CETL) using the South Carolina University Research and Education Foundation (SCUREF) program. A statement of work (SOW) was issued to CETL [6] to perform this work.

  1. Open cycle heat pump development for local resource use. Phase 2: District heating case study analysis

    NASA Astrophysics Data System (ADS)

    Patch, K. D.; Dibella, F. A.; Glick, J. F.; Becker, F. E.

    1990-04-01

    District heating (DH) systems provide thermal energy to their customers in the form of hot water or steam. These systems can use one or more types of heat sources to meet the thermal load, including boilers, cogeneration systems, or low-grade heat sources in conjunction with a heat pump. Most large-scale heat pumps operate using the closed-cycle concept and usually use a chlorinated fluorocarbon (CFC) as the working fluid. An alternative to this approach is the quasi open-cycle heat pump, which was first studied in a Phase 1 report entitled, Open-Cycle Heat Pump Development for Local Resource Use, DOE/CE/26563-5. The quasi open-cycle (QOC) heat pump actually uses the district heating transport medium as its working fluid. This document is the Final Report prepared as a part of Task 6 of Open-Cycle Heat Pump Development for Local Resource Use, Phase 2 District Heating Case Study Analysis. The objective of this study contract was to assess the application of the QOC heat pump in an actual case study.

  2. Characterization of Solid State Phase Transformation in Continuously Heated and Cooled Ferritic Weld Metal

    SciTech Connect

    Narayana, B; Mills, Michael J.; Specht, Eliot D; Santella, Michael L; Babu, Sudarsanam Suresh

    2010-12-01

    Arc welding processes involve cooling rates that vary over a wide range (1-100 K/s). The final microstructire is thus a product of the heating and cooling cycles experienced by the weld in addition to the weld composition. It has been shown that the first phase to form under weld cooling conditions may not be that predicted by equilibrium calculations. The partitioning of different interstitial/substitutional alloying elements at high temperatures can dramatically affect the subsequent phase transformations. In order to understand the effect of alloying on phase transformation temperatures and final microstructures time-resolved X-ray diffraction technique has been successfully used for characterization. The work by Jacot and Rappaz on pearlitic steels provided insight into austenitization of hypoeutectic steels using a finite volume model. However there is very little work done on the effect of heating and cooling rates on the phase transformation paths in bainitic/martensitic steels and weld metals. Previous work on a weld with higher aluminum content, deposited with a FCAW-S process indicated that even at aluminum levels where the primary phase to solidify from liquid should be delta ferrite, non-equilibrium austenite was observed. The presence of inhomogeneity in composition of the parent microstructure has been attributed to differences in transformation modes, temperatures and microstructures in dual-phase, TRIP steels and ferritic welds. The objectives of the work included the identification of the stability regions of different phases during heating and cooling, differences in the effect of weld heating and cooling rates on the phase transformation temperatures, and the variation in phase fractions of austenite and ferrite in the two phase regions as a function of temperature. The base composition used for the present work is a Fe-1%Al-2%Mn-1%Ni-0.04%C weld metal. A pseudo-binary phase diagram shows the expected solidification path under equilibrium conditions. However, the effect of heating and cooling rates on the phase transformation path due to non-equilibrium partitioning of alloying elements cannot be predicted by equilibrium phase diagrams. Also, it is unclear if there is retention of delta ferrite to room temperature due to compositional or thermal effects. This would dramatically affect the austenite to ferrite transformation due to carbon and nitrogen enrichment in the austenite.

  3. Crystallization history of lunar picritic basalt sample 12002 - Phase-equilibria and cooling-rate studies

    NASA Technical Reports Server (NTRS)

    Walker, D.; Kirkpatrick, R. J.; Longhi, J.; Hays, J. F.

    1976-01-01

    Experimental crystallization of a lunar picrite composition (sample 12002) at controlled linear cooling rates produces systematic changes in the temperature at which crystalline phases appear, in the texture, and in crystal morphology as a function of cooling rate. Phases crystallize in the order olivine, chromium spinel, pyroxene, plagioclase, and ilmenite during equilibrium crystallization, but ilmenite and plagioclase reverse their order of appearance and silica crystallizes in the groundmass during controlled cooling experiments. The partition of iron and magnesium between olivine and liquid is independent of cooling rate, temperature, and pressure. Comparison of the olivine nucleation densities in the lunar sample and in the experiments indicates that the sample began cooling at about 1 deg C/hr. Pyroxene size, chemistry, and growth instability spacings, as well as groundmass coarseness, all suggest that the cooling rate subsequently decreased by as much as a factor of 10 or more. The porphyritic texture of this sample, then, is produced at a decreasing, rather than a discontinuously increasing, cooling rate.

  4. Forced Two-Phase Helium Cooling Scheme for the Mu2e Transport Solenoid

    SciTech Connect

    Tatkowski, G.; Cheban, S.; Dhanaraj, N.; Evbota, D.; Lopes, M.; Nicol, T.; Sanders, R.; Schmitt, R.; Voirin, E.

    2015-01-01

    The Mu2e Transport Solenoid (TS) is an S-shaped magnet formed by two separate but similar magnets, TS-u and TS-d. Each magnet is quarter-toroid shaped with a centerline radius of approximately 3 m utilizing a helium cooling loop consisting of 25 to 27 horizontal-axis rings connected in series. This cooling loop configuration has been deemed adequate for cooling via forced single phase liquid helium; however it presents major challenges to forced two-phase flow such as “garden hose” pressure drop, concerns of flow separation from tube walls, difficulty of calculation, etc. Even with these disadvantages, forced two-phase flow has certain inherent advantages which make it a more attractive option than forced single phase flow. It is for this reason that the use of forced two-phase flow was studied for the TS magnets. This paper will describe the analysis using helium-specific pressure drop correlations, conservative engineering approach, helium properties calculated and updated at over fifty points, and how the results compared with those in literature. Based on the findings, the use of forced-two phase helium is determined to be feasible for steady-state cooling of the TS solenoids

  5. Heat pipe radiation cooling (HPRC) for high-speed aircraft propulsion. Phase 2 (feasibility) final report

    SciTech Connect

    Martin, R.A.; Merrigan, M.A.; Elder, M.G.; Sena, J.T.; Keddy, E.S.; Silverstein, C.C.

    1994-03-25

    The National Aeronautics and Space Administration (NASA), Los Alamos National Laboratory (Los Alamos), and CCS Associates are conducting the Heat Pipe Radiation Cooling (HPRC) for High-Speed Aircraft Propulsion program to determine the advantages and demonstrate the feasibility of using high-temperature heat pipes to cool hypersonic engine components. This innovative approach involves using heat pipes to transport heat away from the combustor, nozzle, or inlet regions, and to reject it to the environment by thermal radiation from adjacent external surfaces. HPRC is viewed as an alternative (or complementary) cooling technique to the use of pumped cryogenic or endothermic fuels to provide regenerative fuel or air cooling of the hot surfaces. The HPRC program has been conducted through two phases, an applications phase and a feasibility phase. The applications program (Phase 1) included concept and assessment analyses using hypersonic engine data obtained from US engine company contacts. The applications phase culminated with planning for experimental verification of the HPRC concept to be pursued in a feasibility program. The feasibility program (Phase 2), recently completed and summarized in this report, involved both analytical and experimental studies.

  6. Forced two-phase helium cooling scheme for the Mu2e transport solenoid

    NASA Astrophysics Data System (ADS)

    Tatkowski, G.; Cheban, S.; Dhanaraj, N.; Evbota, D.; Lopes, M.; Nicol, T.; Sanders, R.; Schmitt, R.; Voirin, E.

    2015-12-01

    The Mu2e Transport Solenoid (TS) is an S-shaped magnet formed by two separate but similar magnets, TS-u and TS-d. Each magnet is quarter-toroid shaped with a centerline radius of approximately 3 m utilizing a helium cooling loop consisting of 25 to 27 horizontal-axis rings connected in series. This cooling loop configuration has been deemed adequate for cooling via forced single phase liquid helium; however it presents major challenges to forced two-phase flow such as “garden hose” pressure drop, concerns of flow separation from tube walls, difficulty of calculation, etc. Even with these disadvantages, forced two-phase flow has certain inherent advantages which make it a more attractive option than forced single phase flow. It is for this reason that the use of forced two-phase flow was studied for the TS magnets. This paper will describe the analysis using helium-specific pressure drop correlations, conservative engineering approach, helium properties calculated and updated at over fifty points, and how the results compared with those in literature. Based on the findings, the use of forced-two phase helium is determined to be feasible for steady-state cooling of the TS solenoids.

  7. Optimal design variable considerations in the use of phase change materials in indirect evaporative cooling

    NASA Astrophysics Data System (ADS)

    Chilakapaty, Ankit Paul

    The demand for sustainable, energy efficient and cost effective heating and cooling solutions is exponentially increasing with the rapid advancement of computation and information technology. Use of latent heat storage materials also known as phase change materials (PCMs) for load leveling is an innovative solution to the data center cooling demands. These materials are commercially available in the form of microcapsules dispersed in water, referred to as the microencapsulated phase change slurries and have higher heat capacity than water. The composition and physical properties of phase change slurries play significant role in energy efficiency of the cooling systems designed implementing these PCM slurries. Objective of this project is to study the effect of PCM particle size, shape and volumetric concentration on overall heat transfer potential of the cooling systems designed with PCM slurries as the heat transfer fluid (HTF). In this study uniform volume heat source model is developed for the simulation of heat transfer potential using phase change materials in the form of bulk temperature difference in a fully developed flow through a circular duct. Results indicate the heat transfer potential increases with PCM volumetric concentration with gradually diminishing returns. Also, spherical PCM particles offer greater heat transfer potential when compared to cylindrical particles. Results of this project will aid in efficient design of cooling systems based on PCM slurries.

  8. Photoreversible micellar solution as a smart drag-reducing fluid for use in district heating/cooling systems.

    PubMed

    Shi, Haifeng; Ge, Wu; Oh, Hyuntaek; Pattison, Sean M; Huggins, Jacob T; Talmon, Yeshayahu; Hart, David J; Raghavan, Srinivasa R; Zakin, Jacques L

    2013-01-01

    A photoresponsive micellar solution is developed as a promising working fluid for district heating/cooling systems (DHCs). It can be reversibly switched between a drag reduction (DR) mode and an efficient heat transfer (EHT) mode by light irradiation. The DR mode is advantageous during fluid transport, and the EHT mode is favored when the fluid passes through heat exchangers. This smart fluid is an aqueous solution of cationic surfactant oleyl bis(2-hydroxyethyl)methyl ammonium chloride (OHAC, 3.4 mM) and the sodium salt of 4-phenylazo benzoic acid (ACA, 2 mM). Initially, ACA is in a trans configuration and the OHAC/ACA solution is viscoelastic and exhibits DR (of up to 80% relative to pure water). At the same time, this solution is not effective for heat transfer. Upon UV irradiation, trans-ACA is converted to cis-ACA, and in turn, the solution is converted to its EHT mode (i.e., it loses its viscoelasticity and DR) but it now has a heat-transfer capability comparable to that of water. Subsequent irradiation with visible light reverts the fluid to its viscoelastic DR mode. The above property changes are connected to photoinduced changes in the nanostructure of the fluid. In the DR mode, the OHAC/trans-ACA molecules assemble into long threadlike micelles that impart viscoelasticity and DR capability to the fluid. Conversely, in the EHT mode the mixture of OHAC and cis-ACA forms much shorter cylindrical micelles that contribute to negligible viscoelasticity and effective heat transfer. These nanostructural changes are confirmed by cryo-transmission electron microscopy (cryo-TEM), and the photoisomerization of trans-ACA and cis-ACA is verified by (1)H NMR. PMID:23210742

  9. Study of a splat cooled Cu-Zr-noncrystalline phase.

    NASA Technical Reports Server (NTRS)

    Revcolevschi, A.; Grant, N. J.

    1972-01-01

    By rapid quenching from the melt, using the splat forming gun technique, a noncrystalline phase has been obtained in a Cu-Zr alloy containing 60 at. % Cu. Upon heating, rapid crystallization of the samples takes place at 477 C with a heat release of about 700 cal per mol. The variation of the electrical resistivity of the samples with temperature confirms the transformation. Very high resolution electron microscopy studies of the structural changes of the samples upon heating are presented and show the gradual crystallization of the amorphous structure.

  10. Phase change based cooling for high burst mode heat loads with temperature regulation above the phase change temperature

    DOEpatents

    The United States of America as represented by the United States Department of Energy

    2009-12-15

    An apparatus and method for transferring thermal energy from a heat load is disclosed. In particular, use of a phase change material and specific flow designs enables cooling with temperature regulation well above the fusion temperature of the phase change material for medium and high heat loads from devices operated intermittently (in burst mode). Exemplary heat loads include burst mode lasers and laser diodes, flight avionics, and high power space instruments. Thermal energy is transferred from the heat load to liquid phase change material from a phase change material reservoir. The liquid phase change material is split into two flows. Thermal energy is transferred from the first flow via a phase change material heat sink. The second flow bypasses the phase change material heat sink and joins with liquid phase change material exiting from the phase change material heat sink. The combined liquid phase change material is returned to the liquid phase change material reservoir. The ratio of bypass flow to flow into the phase change material heat sink can be varied to adjust the temperature of the liquid phase change material returned to the liquid phase change material reservoir. Varying the flowrate and temperature of the liquid phase change material presented to the heat load determines the magnitude of thermal energy transferred from the heat load.

  11. Decay-phase cooling and inferred heating of M- and X-class solar flares

    SciTech Connect

    Ryan, Daniel F.; Gallagher, Peter T.; Chamberlin, Phillip C.; Milligan, Ryan O.

    2013-11-20

    In this paper, the cooling of 72 M- and X-class flares is examined using GOES/XRS and SDO/EVE. The observed cooling rates are quantified and the observed total cooling times are compared with the predictions of an analytical zero-dimensional hydrodynamic model. We find that the model does not fit the observations well, but does provide a well-defined lower limit on a flare's total cooling time. The discrepancy between observations and the model is then assumed to be primarily due to heating during the decay phase. The decay-phase heating necessary to account for the discrepancy is quantified and found be ∼50% of the total thermally radiated energy, as calculated with GOES. This decay-phase heating is found to scale with the observed peak thermal energy. It is predicted that approximating the total thermal energy from the peak is minimally affected by the decay-phase heating in small flares. However, in the most energetic flares the decay-phase heating inferred from the model can be several times greater than the peak thermal energy.

  12. Development of a prototype thermoelectric space cooling system using phase change material to improve the performance

    NASA Astrophysics Data System (ADS)

    Zhao, Dongliang

    The thermoelectric cooling system has advantages over conventional vapor compression cooling devices, including compact in size, light in weight, high reliability, no mechanical moving parts, no refrigerant, being powered by direct current, and easily switching between cooling and heating modes. However, it has been long suffering from its relatively high cost and low energy efficiency, which has restricted its usage to niche applications, such as space missions, portable cooling devices, scientific and medical equipment, where coefficient of performance (COP) is not as important as reliability, energy availability, and quiet operation environment. Enhancement of thermoelectric cooling system performance generally relies on two methods: improving thermoelectric material efficiency and through thermoelectric cooling system thermal design. This research has been focused on the latter one. A prototype thermoelectric cooling system integrated with phase change material (PCM) thermal energy storage unit for space cooling has been developed. The PCM thermal storage unit used for cold storage at night, functions as the thermoelectric cooling system's heat sink during daytime's cooling period and provides relatively lower hot side temperature for the thermoelectric cooling system. The experimental test of the prototype system in a reduced-scale chamber has realized an average cooling COP of 0.87, with the maximum value of 1.22. Another comparison test for efficacy of PCM thermal storage unit shows that 35.3% electrical energy has been saved from using PCM for the thermoelectric cooling system. In general, PCM faces difficulty of poor thermal conductivity at both solid and liquid phases. This system implemented a finned inner tube to increase heat transfer during PCM charging (melting) process that directly impacts thermoelectric system's performance. A simulation tool for the entire system has been developed including mathematical models for a single thermoelectric module, for the thermoelectric cooling unit, for the PCM thermal storage unit, and for the outdoor air-water heat exchanger. When modeling PCM thermal storage unit, the enthalpy method has been adopted. Since natural convection has been observed in experiments playing a key effect on heat transfer in PCM, a staged effective thermal conductivity (ke) concept and modified Rayleigh (Ra) number formula have been developed to better capture natural convection's variable effects during the PCM charging process. Therefore, a modeling-based design procedure for thermoelectric cooling system integrating with PCM has been proposed. A case study has been completed for a model office room to demonstrate the qualitative and quantitative evaluations to the major system components. Results of this research can be extended to other applications in relevant areas. For instance, the proposed PCM thermal storage unit can be applied to integration with water-cooled conventional air-conditioning devices. Instead of using water cooling, a case study of using the proposed PCM unit for a water-cooled air-conditioner shows a COP increase of more than 25.6%.

  13. Miniature cryogenic cooling system with split-phase dual compressor and phase-shifting device

    SciTech Connect

    Lam, C.K.

    1984-10-30

    A miniature cryogenic cooling system having low microphonics and thermophonics. THe apparatus includes a cold finger incorporating primary and secondary working volumes and their associated regenerative beds. Both volumes are adapted to effect cooling. A displacer reciprocates within the cold finger under the influence of push-pull pressure waves from a dual compressor assembly. The cold finger includes an arrangement for providing pneumatic cushioning of the reciprocating displacer to control displacer slamming.

  14. Phase-difference and spectroscopic imaging for monitoring of human brain temperature during cooling.

    PubMed

    Weis, Jan; Covaciu, Lucian; Rubertsson, Sten; Allers, Mats; Lunderquist, Anders; Ortiz-Nieto, Francisco; Ahlström, Håkan

    2012-12-01

    Decrease of the human brain temperature was induced by intranasal cooling. The main purpose of this study was to compare the two magnetic resonance methods for monitoring brain temperature changes during cooling: phase-difference and magnetic resonance spectroscopic imaging (MRSI) with high spatial resolution. Ten healthy volunteers were measured. Selective brain cooling was performed through nasal cavities using saline-cooled balloon catheters. MRSI was based on a radiofrequency spoiled gradient echo sequence. The spectral information was encoded by incrementing the echo time of the subsequent eight image records. Reconstructed voxel size was 1×1×5 mm(3). Relative brain temperature was computed from the positions of water spectral lines. Phase maps were obtained from the first image record of the MRSI sequence. Mild hypothermia was achieved in 15-20 min. Mean brain temperature reduction varied in the interval <-3.0; -0.6>°C and <-2.7; -0.7>°C as measured by the MRSI and phase-difference methods, respectively. Very good correlation was found in all locations between the temperatures measured by both techniques except in the frontal lobe. Measurements in the transversal slices were more robust to the movement artifacts than those in the sagittal planes. Good agreement was found between the MRSI and phase-difference techniques. PMID:22819582

  15. Optoacoustic detection of a kinetic-cooling effect in the liquid phase

    NASA Astrophysics Data System (ADS)

    Park, Seung Min; Shin, Keon Bae

    1995-11-01

    A kinetic-cooling effect in the liquid phase has been observed by the use of pulsed optoacoustic spectroscopy. The magnitude of the optoacoustic signal in an aqueous Eu^3+ solution, as measured from the absorption of pulsed light, was found to decrease when the excitation-laser wavelength was tuned to the transition from the thermally excited ^7F1 state to the upper electronic ^5D0 state of Eu^3+ ion. This anomalous optoacoustic phenomenon is attributed to the kinetic-cooling effect.

  16. Two-phase flow in the cooling circuit of a cryogenic rocket engine

    NASA Astrophysics Data System (ADS)

    Preclik, D.

    1992-07-01

    Transient two-phase flow was investigated for the hydrogen cooling circuit of the HM7 rocket engine. The nuclear reactor code ATHLET/THESEUS was adapted to cryogenics and applied to both principal and prototype experiments for validation and simulation purposes. The cooling circuit two-phase flow simulation focused on the hydrogen prechilling and pump transient phase prior to ignition. Both a single- and a multichannel model were designed and employed for a valve leakage flow, a nominal prechilling flow, and a prechilling with a subsequent pump-transient flow. The latter case was performed in order to evaluate the difference between a nominal and a delayed turbo-pump start-up. It was found that an extension of the nominal prechilling sequence in the order of 1 second is sufficient to finally provide for liquid injection conditions of hydrogen which, as commonly known, is undesirable for smooth ignition and engine starting transients.

  17. Transformation behavior of the γU(Zr,Nb) phase under continuous cooling conditions

    NASA Astrophysics Data System (ADS)

    Komar Varela, C. L.; Gribaudo, L. M.; González, R. O.; Aricó, S. F.

    2014-10-01

    The selected alloy for designing a high-density monolithic-type nuclear fuel with U-Zr-Nb alloy as meat and Zry-4 as cladding, has to remain in the γU(Zr,Nb) phase during the whole fabrication process. Therefore, it is necessary to define a range of concentrations in which the γU(Zr,Nb) phase does not decompose under the process conditions. In this work, several U alloys with concentrations between 28.2-66.9 at.% Zr and 0-13.3 at.% Nb were fabricated to study the possible transformations of the γU(Zr,Nb) phase under different continuous cooling conditions. The results of the electrical resistivity vs temperature experiments are presented. For a cooling rate of 4 °C/min a linear regression was determined by fitting the starting decomposition temperature as a function of Nb concentration. Under these conditions, a concentration of 45.3 at.% Nb would be enough to avoid any transformation of the γU(Zr,Nb) phase. In experiments that involve higher cooling conditions, it has been determined that this concentration can be halved.

  18. Cool Shelter

    ERIC Educational Resources Information Center

    Praeger, Charles E.

    2005-01-01

    Amid climbing energy costs and tightening budgets, administrators at school districts, colleges and universities are looking for all avenues of potential savings while promoting sustainable communities. Cool metal roofing can save schools money and promote sustainable design at the same time. Cool metal roofing keeps the sun's heat from collecting

  19. Cool Shelter

    ERIC Educational Resources Information Center

    Praeger, Charles E.

    2005-01-01

    Amid climbing energy costs and tightening budgets, administrators at school districts, colleges and universities are looking for all avenues of potential savings while promoting sustainable communities. Cool metal roofing can save schools money and promote sustainable design at the same time. Cool metal roofing keeps the sun's heat from collecting…

  20. User manual for GEOCITY: a computer model for cost analysis of geothermal district-heating-and-cooling systems. Volume I. Main text

    SciTech Connect

    Huber, H.D.; Fassbender, L.L.; Bloomster, C.H.

    1982-09-01

    The purpose of this model is to calculate the costs of residential space heating, space cooling, and sanitary water heating or process heating (cooling) using geothermal energy from a hydrothermal reservoir. The model can calculate geothermal heating and cooling costs for residential developments, a multi-district city, or a point demand such as an industrial factory or commercial building. GEOCITY simulates the complete geothermal heating and cooling system, which consists of two principal parts: the reservoir and fluid transmission system and the distribution system. The reservoir and fluid transmission submodel calculates the life-cycle cost of thermal energy supplied to the distribution system by simulating the technical design and cash flows for the exploration, development, and operation of the reservoir and fluid transmission system. The distribution system submodel calculates the life-cycle cost of heat (chill) delivered by the distribution system to the end-users by simulating the technical design and cash flows for the construction and operation of the distribution system. Geothermal space heating is assumed to be provided by circulating hot water through radiators, convectors, fan-coil units, or other in-house heating systems. Geothermal process heating is provided by directly using the hot water or by circulating it through a process heat exchanger. Geothermal space or process cooling is simulated by circulating hot water through lithium bromide/water absorption chillers located at each building. Retrofit costs for both heating and cooling applications can be input by the user. The life-cycle cost of thermal energy from the reservoir and fluid transmission system to the distribution system and the life-cycle cost of heat (chill) to the end-users are calculated using discounted cash flow analysis.

  1. A SINDA modeling technique for pumped two-phase spacecraft cooling systems

    NASA Technical Reports Server (NTRS)

    Ollendorf, S.; Costello, F. A.

    1984-01-01

    The purpose of this paper is to present a modeling technique that has proven successful in simulating pumped, two-phase cooling systems. The technique uses the standard SINDA thermal-analysis program and thereby extends the capabilities of SINDA to complex, active spacecraft thermal-control systems. This paper provides sufficient detail that a current SINDA user will be able to apply the technique by reference to this paper alone.

  2. Planning for Quality Schools: Meeting the Needs of District Families. Phase One: Understanding Current School Supply and Student Enrollment Patterns

    ERIC Educational Resources Information Center

    Garrison, David; Allen, Marni; Turner, Margery; Comey, Jennifer; Williams, Barika; Guernsey, Elizabeth; Filardo, Mary; Huvendick, Nancy; Sung, Ping

    2008-01-01

    This report is the first phase of a three-part Quality Schools Project to help the District of Columbia create a firm analytical basis for planning for quality schools to meet the needs of the city's families. The Quality School Project is a joint effort of the DC Office of the State Superintendent of Education, the 21st Century School Fund, the

  3. Cooling/heating-assisted headspace solid-phase microextraction of polycyclic aromatic hydrocarbons from contaminated soils.

    PubMed

    Ghiasvand, Ali Reza; Pirdadeh-Beiranvand, Masoumeh

    2015-11-01

    A simple, low-cost, and effective cooling/heating-assisted headspace solid-phase microextraction (CHA-HS-SPME) device, capable of direct cooling the fiber to low temperatures and simultaneous heating the sample matrix to high temperatures, was fabricated and evaluated. It was able to cool down the commercial and handmade fibers for the effective tapping of volatile and semi-volatile species in the headspace of complex solid matrices, with minimal manipulation compared with conventional SPME. The CHA-HS-SPME system can create large temperature gaps (up to 200 °C) between the fiber and the sample matrix, because the cooling process is directly applied onto the fiber. Different effective experimental parameters for the fabrication of the CHA-HS-SPME device as well as for the extraction and determination of polycyclic aromatic hydrocarbons (PAHs) from solid samples were evaluated and optimized. The proposed device coupled to GC-FID was successfully applied for the extraction and determination of PAHs in contaminated soils without any sample pretreatment step. Good agreement was observed between the results obtained by the proposed CHA-HS-SPME-GC-FID method and those achieved by validated method. PMID:26572839

  4. Effect of Cooling Rate on Phase Transformations in a High-Strength Low-Alloy Steel Studied from the Liquid Phase

    NASA Astrophysics Data System (ADS)

    Dorin, Thomas; Stanford, Nicole; Taylor, Adam; Hodgson, Peter

    2015-12-01

    The phase transformation and precipitation in a high-strength low-alloy steel have been studied over a large range of cooling rates, and a continuous cooling transformation (CCT) diagram has been produced. These experiments are unique because the measurements were made from samples cooled directly from the melt, rather than in homogenized and re-heated billets. The purpose of this experimental design was to examine conditions pertinent to direct strip casting. At the highest cooling rates which simulate strip casting, the microstructure was fully bainitic with small regions of pearlite. At lower cooling rates, the fraction of polygonal ferrite increased and the pearlite regions became larger. The CCT diagram and the microstructural analysis showed that the precipitation of NbC is suppressed at high cooling rates, and is likely to be incomplete at intermediate cooling rates.

  5. Vapor phase strengthening of nickel-based alloys for actively-cooled thermostructural panels

    NASA Astrophysics Data System (ADS)

    Perez-Bergquist, Sara Jane

    Actively cooled thermostructural panels for use in emerging hypersonic flight systems require the use of advanced materials able to support substantial loads at elevated temperatures. A major challenge in this advancing technology is identifying formable structural materials that are strong, tough and oxidation resistant. For thermostructural panels to be optimized for low mass with an appropriate combination of mechanical strength and cooling capacity, the panel is required to have a thin-walled geometry. Advanced, high strength cast Ni-based alloys have attractive properties, but the fabrication of sub-millimeter walls with conventional casting processes would be extremely challenging. The purpose of this study is to develop a new processing path that would result in a rectangular channeled panel made of a nickel-based precipitation strengthened alloy in a previously unobtainable thin-walled geometry suitable for active cooling. Beginning with thin sheets of Ni-based solid-solution alloys and subsequently strengthening the material by vapor phase aluminization combined with an annealing treatment, this objective is accomplished. This study includes selecting a wrought nickel-based alloy as the base substrate for panel fabrication, determining a goal gamma + gamma' microstructure, fabricating rectangular channeled panels, and testing the actively cooled panels at high temperature. Thermodynamic, yield strength, and panel geometry modeling was integrated to determine an optimized geometry and microstructure for the strengthened panel. Panels were fabricated with the optimized geometry and tested at high temperature with active cooling in both the as-fabricated and strengthened states. The strengthened panel was able to withstand a temperature 478°C higher than the as-fabricated panel indicating the increase in strengthening and temperature capability possible with this process.

  6. Dynamic evolution of liquid-liquid phase separation during continuous cooling

    SciTech Connect

    Imhoff, S. D.; Gibbs, P. J.; Katz, M. R.; Ott, T. J.; Patterson, B. M.; Lee, W. -K.; Fezzaa, K.; Cooley, J. C.; Clarke, A. J.

    2015-03-01

    Solidification from a multiphase fluid involves many unknown quantities due to the difficulty of predicting the impact of fluid flow on chemical partitioning. Real-time x-ray radiography has been used to observe liquideliquid phase separation in Al90In10 prior to solidification. Quantitative image analysis has been used to measure the motion and population characteristics of the dispersed indium-rich liquid phase during cooling. Here we determine that the droplet growth characteristics resemble well known steady-state coarsening laws with likely enhancement by concurrent growth due to supersaturation. Simplistic views of droplet motion are found to be insufficient until late in the reaction due to a hydrodynamic instability caused by the large density difference between the dispersed and matrix liquid phases.

  7. Dynamic evolution of liquid–liquid phase separation during continuous cooling

    DOE PAGESBeta

    Imhoff, Seth D.; Gibbs, Paul J.; Katz, Martha R.; Ott, Thomas J.; Patterson, Brian M.; Lee, Wah-Keat; Fezzaa, Kamel; Cooley, Jason C.; Clarke, Amy J.

    2015-01-06

    Solidification from a multiphase fluid involves many unknown quantities due to the difficulty of predicting the impact of fluid flow on chemical partitioning. Real-time x-ray radiography was used to observe liquid-liquid phase separation in Al90In10 prior to solidification. Quantitative image analysis was used to measure the motion and population characteristics of the dispersed indium-rich liquid phase during cooling. Here we determine that the droplet growth characteristics resemble well known steady-state coarsening laws with likely enhancement by concurrent growth due to supersaturation. Simplistic views of droplet motion are found to be insufficient until late in the reaction due to a hydrodynamicmore » instability caused by the large density difference between the dispersed and matrix liquid phases.« less

  8. Dynamic evolution of liquid–liquid phase separation during continuous cooling

    SciTech Connect

    Imhoff, Seth D.; Gibbs, Paul J.; Katz, Martha R.; Ott, Thomas J.; Patterson, Brian M.; Lee, Wah-Keat; Fezzaa, Kamel; Cooley, Jason C.; Clarke, Amy J.

    2015-01-06

    Solidification from a multiphase fluid involves many unknown quantities due to the difficulty of predicting the impact of fluid flow on chemical partitioning. Real-time x-ray radiography was used to observe liquid-liquid phase separation in Al90In10 prior to solidification. Quantitative image analysis was used to measure the motion and population characteristics of the dispersed indium-rich liquid phase during cooling. Here we determine that the droplet growth characteristics resemble well known steady-state coarsening laws with likely enhancement by concurrent growth due to supersaturation. Simplistic views of droplet motion are found to be insufficient until late in the reaction due to a hydrodynamic instability caused by the large density difference between the dispersed and matrix liquid phases.

  9. Carbon-based nanostructured surfaces for enhanced phase-change cooling

    NASA Astrophysics Data System (ADS)

    Selvaraj Kousalya, Arun

    To maintain acceptable device temperatures in the new generation of electronic devices under development for high-power applications, conventional liquid cooling schemes will likely be superseded by multi-phase cooling solutions to provide substantial enhancement to the cooling capability. The central theme of the current work is to investigate the two-phase thermal performance of carbon-based nanostructured coatings in passive and pumped liquid-vapor phase-change cooling schemes. Quantification of the critical parameters that influence thermal performance of the carbon nanostructured boiling surfaces presented herein will lead to improved understanding of the underlying evaporative and boiling mechanisms in such surfaces. A flow boiling experimental facility is developed to generate consistent and accurate heat transfer performance curves with degassed and deionized water as the working fluid. New means of boiling heat transfer enhancement by altering surface characteristics such as surface energy and wettability through light-surface interactions is explored in this work. In this regard, carbon nanotube (CNT) coatings are exposed to low-intensity irradiation emitted from a light emitting diode and the subcooled flow boiling performance is compared against a non-irradiated CNT-coated copper surface. A considerable reduction in surface superheat and enhancement in average heat transfer coefficient is observed. In another work involving CNTs, the thermal performance of CNT-integrated sintered wick structures is evaluated in a passively cooled vapor chamber. A physical vapor deposition process is used to coat the CNTs with varying thicknesses of copper to promote surface wetting with the working fluid, water. Thermal performance of the bare sintered copper powder sample and the copper-functionalized CNT-coated sintered copper powder wick samples is compared using an experimental facility that simulates the capillary fluid feeding conditions of a vapor chamber. Nanostructured samples having a thicker copper coating provided a considerable increase in dryout heat flux while maintaining lower surface superheat temperatures compared to a bare sintered powder sample; this enhancement is attributed primarily to the improved surface wettability. Dynamic contact angle measurements are conducted to quantitatively compare the surface wetting trends for varying copper coating thicknesses and confirm the increase in hydrophilicity with increasing coating thickness. The second and relatively new carbon nanostructured coating, carbon nanotubes decorated with graphitic nanopetals, are used as a template to manufacture boiling surfaces with heterogeneous wettability. Heat transfer surfaces with parallel alternating superhydrophobic and superhydrophilic stripes are fabricated by a combination of oxygen plasma treatment, Teflon coating and shadow masking. Such composite wetting surfaces exhibit enhanced flow-boiling performance compared to homogeneous wetting surfaces. Flow visualization studies elucidate the physical differences in nucleate boiling mechanisms between the different heterogeneous wetting surfaces. The third and the final carbon nanomaterial, graphene, is examined as an oxidation barrier coating for liquid and liquid-vapor phase-change cooling systems. Forced convection heat transfer experiments on bare and graphene-coated copper surfaces reveal nearly identical liquid-phase and two-phase thermal performance for the two surfaces. Surface analysis after thermal testing indicates significant oxide formation on the entire surface of the bare copper substrate; however, oxidation is observed only along the grain boundaries of the graphene-coated substrate. Results suggest that few-layer graphene can act as a protective layer even under vigorous flow boiling conditions, indicating a broad application space of few-layer graphene as an ultra-thin oxidation barrier coating.

  10. Advanced phase change materials and systems for solar passive heating and cooling of residential buildings

    SciTech Connect

    Salyer, I.O.; Sircar, A.K.; Dantiki, S.

    1988-01-01

    During the last three years under the sponsorship of the DOE Solar Passive Division, the University of Dayton Research Institute (UDRI) has investigated four phase change material (PCM) systems for utility in thermal energy storage for solar passive heating and cooling applications. From this research on the basis of cost, performance, containment, and environmental acceptability, we have selected as our current and most promising series of candidate phase change materials, C-15 to C-24 linear crystalline alkyl hydrocarbons. The major part of the research during this contract period was directed toward the following three objectives. Find, test, and develop low-cost effective phase change materials (PCM) that melt and freeze sharply in the comfort temperature range of 73--77{degree}F for use in solar passive heating and cooling of buildings. Define practical materials and processes for fire retarding plasterboard/PCM building products. Develop cost-effective methods for incorporating PCM into building construction materials (concrete, plasterboard, etc.) which will lead to the commercial manufacture and sale of PCM-containing products resulting in significant energy conservation.

  11. Self-shaping of oil droplets via the formation of intermediate rotator phases upon cooling.

    PubMed

    Denkov, Nikolai; Tcholakova, Slavka; Lesov, Ivan; Cholakova, Diana; Smoukov, Stoyan K

    2015-12-17

    Revealing the chemical and physical mechanisms underlying symmetry breaking and shape transformations is key to understanding morphogenesis. If we are to synthesize artificial structures with similar control and complexity to biological systems, we need energy- and material-efficient bottom-up processes to create building blocks of various shapes that can further assemble into hierarchical structures. Lithographic top-down processing allows a high level of structural control in microparticle production but at the expense of limited productivity. Conversely, bottom-up particle syntheses have higher material and energy efficiency, but are more limited in the shapes achievable. Linear hydrocarbons are known to pass through a series of metastable plastic rotator phases before freezing. Here we show that by using appropriate cooling protocols, we can harness these phase transitions to control the deformation of liquid hydrocarbon droplets and then freeze them into solid particles, permanently preserving their shape. Upon cooling, the droplets spontaneously break their shape symmetry several times, morphing through a series of complex regular shapes owing to the internal phase-transition processes. In this way we produce particles including micrometre-sized octahedra, various polygonal platelets, O-shapes, and fibres of submicrometre diameter, which can be selectively frozen into the corresponding solid particles. This mechanism offers insights into achieving complex morphogenesis from a system with a minimal number of molecular components. PMID:26649824

  12. Self-shaping of oil droplets via the formation of intermediate rotator phases upon cooling

    NASA Astrophysics Data System (ADS)

    Denkov, Nikolai; Tcholakova, Slavka; Lesov, Ivan; Cholakova, Diana; Smoukov, Stoyan K.

    2015-12-01

    Revealing the chemical and physical mechanisms underlying symmetry breaking and shape transformations is key to understanding morphogenesis. If we are to synthesize artificial structures with similar control and complexity to biological systems, we need energy- and material-efficient bottom-up processes to create building blocks of various shapes that can further assemble into hierarchical structures. Lithographic top-down processing allows a high level of structural control in microparticle production but at the expense of limited productivity. Conversely, bottom-up particle syntheses have higher material and energy efficiency, but are more limited in the shapes achievable. Linear hydrocarbons are known to pass through a series of metastable plastic rotator phases before freezing. Here we show that by using appropriate cooling protocols, we can harness these phase transitions to control the deformation of liquid hydrocarbon droplets and then freeze them into solid particles, permanently preserving their shape. Upon cooling, the droplets spontaneously break their shape symmetry several times, morphing through a series of complex regular shapes owing to the internal phase-transition processes. In this way we produce particles including micrometre-sized octahedra, various polygonal platelets, O-shapes, and fibres of submicrometre diameter, which can be selectively frozen into the corresponding solid particles. This mechanism offers insights into achieving complex morphogenesis from a system with a minimal number of molecular components.

  13. Numerical Study of Conjugate Natural Convection Heat Transfer Using One Phase Liquid Cooling

    NASA Astrophysics Data System (ADS)

    Gdhaidh, F. A.; Hussain, K.; Qi, H. S.

    2014-07-01

    A numerical study in 3-D is performed using water as a cooling fluid to investigate the one phase natural convection heat transfer within enclosure. A heat source representing a computer CPU mounted on one vertical wall of a rectangular enclosure is simulated while a heat sink is installed on the opposite vertical wall of the enclosure. The air flow inside the computer compartment is created by using an exhaust fan, and the flow is assumed to be turbulent. The applied power considered ranges from 15 - 40 W. In order to determine the thermal behaviour of the cooling system, the effect of the heat input and the dimension of the enclosure are investigated. The results illustrate that as the size of the enclosure increase the chip temperature declined. However the drop in the temperature is very small when the width increased more than 50 mm. When the enclosure was filled with water the temperature was reduced by 38%. Also the cooling system maintains the maximum chip temperature at 71.5 °C when the heat input of 40 W was assumed and this is within the current recommended computer electronic chips temperature of no more than 85°C.

  14. The impact of a phase-change cooling vest on heat strain and the effect of different cooling pack melting temperatures.

    PubMed

    House, James R; Lunt, Heather C; Taylor, Rowan; Milligan, Gemma; Lyons, Jason A; House, Carol M

    2013-05-01

    Cooling vests (CV) are often used to reduce heat strain. CVs have traditionally used ice as the coolant, although other phase-change materials (PCM) that melt at warmer temperatures have been used in an attempt to enhance cooling by avoiding vasoconstriction, which supposedly occurs when ice CVs are used. This study assessed the effectiveness of four CVs that melted at 0, 10, 20 and 30 °C (CV₀, CV₁₀, CV₂₀, and CV₃₀) when worn by 10 male volunteers exercising and then recovering in 40 °C air whilst wearing fire-fighting clothing. When compared with a non-cooling control condition (CON), only the CV₀ and CV₁₀ vests provided cooling during exercise (40 and 29 W, respectively), whereas all CVs provided cooling during resting recovery (CV₀ 69 W, CV₁₀ 66 W, CV₂₀ 55 W and CV₃₀ 29 W) (P < 0.05). In all conditions, skin blood flow increased when exercising and reduced during recovery, but was lower in the CV₀ and CV₁₀ conditions compared with control during exercise (observed power 0.709) (P < 0.05), but not during resting recovery (observed power only 0.55). The participants preferred the CV₁₀ to the CV₀, which caused temporary erythema to underlying skin, although this resolved overnight after each occurrence. Consequently, a cooling vest melting at 10 °C would seem to be the most appropriate choice for cooling during combined work and rest periods, although possibly an ice-vest (CV₀) may also be appropriate if more insulation was worn between the cooling packs and the skin than used in this study. PMID:23160652

  15. Phase coexistence and transformations in field-cooled ternary piezoelectric single crystals near the morphotropic phase boundary

    SciTech Connect

    Luo, Chengtao; Wang, Yaojin Wang, Zhiguang; Ge, Wenwei; Li, Jiefang; Viehland, D.; Luo, Haosu

    2014-12-08

    Structural phase transformations in (100)-oriented Pb(In{sub 1/2}Nb{sub 1/2})O{sub 3}-Pb(Mg{sub 1/3}Nb{sub 2/3})O{sub 3}-PbTiO{sub 3} single crystals have been investigated by X-ray diffraction. A cubic (C) → tetragonal (T) → monoclinic-C (M{sub C}) transformation sequence was observed in the field-cooled condition. Two phase coexistence regions of C + T and T + M{sub C} were found. In addition to an increase in the C → T phase transition temperature and a decrease of the T → M{sub C} one, a broadening of the coexistence regions was also found with increasing field. This broadening can be explained by the presence of polar nano regions within the C, T, and M{sub C} phase regions.

  16. Mpemba effect and phase transitions in the adiabatic cooling of water before freezing

    NASA Astrophysics Data System (ADS)

    Esposito, S.; De Risi, R.; Somma, L.

    2008-02-01

    In this paper, an accurate experimental investigation of the Mpemba effect (that is, of the fact that initially hot water freezes before the colder one) is carried out, showing that, in the adiabatic cooling of water, relevant roles are played by supercooling, and by phase transitions which take place at 6±1 ∘C,3.5±0.5 ∘C and 1.3±0.6 ∘C. The last transition, which occurs with the non-negligible probability of 0.21 with respect to the total number of runs performed, has not been detected earlier. On the basis of our experimental results, we can present a thorough theoretical analysis of supercooling and of such phase transitions, which are interpreted in terms of the different ordering of molecule clusters in water.

  17. Nonlinear ultrasonic phased array imaging of closed cracks using global preheating and local cooling

    NASA Astrophysics Data System (ADS)

    Ohara, Yoshikazu; Takahashi, Koji; Ino, Yoshihiro; Yamanaka, Kazushi

    2015-10-01

    Closed cracks are the main cause of underestimation in ultrasonic inspection, because the ultrasound transmits through the crack. Specifically, the measurement of closed-crack depth in coarse-grained materials, which are highly attenuative due to linear scatterings at the grains, is the most difficult issue. To solve this problem, we have developed a temporary crack opening method, global preheating and local cooling (GPLC), using tensile thermal stress, and a high-selectivity imaging method, load difference phased array (LDPA), based on the subtraction of phased array images between different stresses. To demonstrate our developed method, we formed a closed fatigue crack in coarse-grained stainless steel (SUS316L) specimen. As a result of applying it to the specimen, the high-selectivity imaging performance was successfully demonstrated. This will be useful in improving the measurement accuracy of closed-crack depths in coarse-grained material.

  18. Open cycle heat pump development: Phase II, District heating case study analysis: Progress report, October 1988--December 31, 1988

    SciTech Connect

    DiBella, F.; Becker, F.E.; Glick, J.

    1989-04-01

    A district heating system is proposed that uses low-level waste-energy sources, and a quasi open-cycle steam heat pump as a means of upgrading the energy in the form of hot water to use as a transport medium in the system. The use of a water-based, open-cycle heat pump appears to be extremely well suited in terms of its potential thermodynamic performance, cost, and environmental safety compared to more typical organic gased closed cycle systems. The Phase II case study provides a detailed analysis of a district heating system that utilizes the open cycle steam heat pump concept developed in Phase I. This quarterly report describes the energy audit performed on the heat source and heat sink.

  19. Beyond optical molasses: 3D raman sideband cooling of atomic cesium to high phase-space density

    PubMed

    Kerman; Vuletic; Chin; Chu

    2000-01-17

    We demonstrate a simple, general purpose method to cool neutral atoms. A sample containing 3x10(8) cesium atoms prepared in a magneto-optical trap is cooled and simultaneously spin polarized in 10 ms at a density of 1.1x10(11) cm (-3) to a phase space density nlambda(3)(dB) = 1/500, which is almost 3 orders of magnitude higher than attainable in free space with optical molasses. The technique is based on 3D degenerate Raman sideband cooling in optical lattices and remains efficient even at densities where the mean lattice site occupation is close to unity. PMID:11015933

  20. Legionnaires' Disease Bacterium in power-plant cooling systems: Phase 1. Final report

    SciTech Connect

    Christensen, S.W.; Solomon, J.A.; Gough, S.B.; Tyndall, R.L.; Fliermans, C.B.

    1983-06-01

    A survey was undertaken of the distribution, density, viability, and infectivity of Legionnaires' Disease Bacteria (Legionella) in power plant cooling systems. Water samples were collected during each of the four seasons at various locations within each of nine power plants and from ambient waters at each site. Measurements of a number of physical and chemical characteristics were made, and Legionella profiles (density, viability, and infectivity for guinea pigs) were obtained. Legionella were detected in nearly all samples. Water from closed-cycle cooling systems frequently had lower densities of Legionella than the ambient water. Nonetheless, infectious Legionella, as defined by their isolation from inoculated guinea pigs, were significantly more likely to be found in samples from the plant-exposed water of closed-cycle plants than in samples from once-through plants or in ambient samples. A new species (L. oakridgensis) was initially isolated from two of the sites, and it has since been found to have a widespread distribution. Two other organisms found to cause illness in guinea pigs may also be new species. Phase II of the project involves investigating possible cause/effect relationships between physicochemical variables and Legionella. This work may contribute toward eventual control techniques for this pathogen.

  1. A novel personal cooling system (PCS) incorporated with phase change materials (PCMs) and ventilation fans: An investigation on its cooling efficiency.

    PubMed

    Lu, Yehu; Wei, Fanru; Lai, Dandan; Shi, Wen; Wang, Faming; Gao, Chuansi; Song, Guowen

    2015-08-01

    Personal cooling systems (PCS) have been developed to mitigate the impact of severe heat stress for humans working in hot environments. It is still a great challenge to develop PCSs that are portable, inexpensive, and effective. We studied the performance of a new hybrid PCS incorporating both ventilation fans and phase change materials (PCMs). The cooling efficiency of the newly developed PCS was investigated on a sweating manikin in two hot conditions: hot humid (HH, 34°C, 75% RH) and hot dry (HD, 34°C, 28% RH). Four test scenarios were selected: fans off with no PCMs (i.e., Fan-off, the CONTROL), fans on with no PCMs (i.e., Fan-on), fans off with fully solidified PCMs (i.e., PCM+Fan-off), and fans on with fully solidified PCMs (i.e., PCM+Fan-on). It was found that the addition of PCMs provided a 54∼78min cooling in HH condition. In contrast, the PCMs only offered a 19-39min cooling in HD condition. In both conditions, the ventilation fans greatly enhanced the evaporative heat loss compared with Fan-off. The hybrid PCS (i.e., PCM+Fan-on) provided a continuous cooling effect during the three-hour test and the average cooling rate for the whole body was around 111 and 315W in HH and HD conditions, respectively. Overall, the new hybrid PCS may be an effective means of ameliorating symptoms of heat stress in both hot-humid and hot-dry environments. PMID:26267508

  2. Rotationally resolved infrared spectroscopy of a jet-cooled phenyl radical in the gas phase.

    PubMed

    Sharp, Erin N; Roberts, Melanie A; Nesbitt, David J

    2008-11-28

    The first high-resolution IR spectra of a jet-cooled phenyl radical are reported, obtained via direct absorption laser spectroscopy in a slit-jet discharge supersonic expansion. The observed A-type band arises from fundamental excitation of the out-of-phase symmetric CH stretch mode (nu19) of b2 symmetry. Unambiguous spectral assignment of the rotational structure to the phenyl radical is facilitated by comparison with precision 2-line combination differences from Fourier transform microwave and direct absorption mm-wave measurements on the ground state [R. J. McMahon et al., Astrophys. J., 2003, 590, L61]. Least-squares fits to an asymmetric top Hamiltonian permit the upper-state rotational constants to be obtained. The corresponding gas-phase vibrational band origin at 3071.8904 (10) cm(-1) is in remarkably good agreement with previous matrix isolation studies [A. V. Friderichsen et al., J. Am. Chem. Soc., 2001, 123, 1977], and indicates only a relatively minor red shift (approximately 0.9 cm(-1)) between the gas and Ar matrix phase environment. Such studies offer considerable promise for further high resolution IR study of other aromatic radical species of particular relevance to combustion phenomena and interstellar chemistry. PMID:18989469

  3. Arsenic speciation in pyrite and secondary weathering phases, Mother Lode gold district, Tuolumne County, California

    SciTech Connect

    Savage, K.S.; Tingle, Tracy N.; O'Day, Peggy A.; Waychunas, Glenn A.; Bird, Dennis K.

    2004-10-27

    Arsenian pyrite, formed during Cretaceous gold mineralization, is the primary source of As along the Melones fault zone in the southern Mother Lode Gold District of California. Mine tailings and associated weathering products from partially submerged inactive gold mines at Don Pedro Reservoir, on the Tuolumne River, contain approx. 20-1300 ppm As. The highest concentrations are in weathering crusts from the Clio mine and nearby outcrops which contain goethite or jarosite. As is concentrated up to 2150 ppm in the fine-grained (<63 mu-m) fraction of these Fe-rich weathering products. Individual pyrite grains in albite-chlorite schists of the Clio mine tailings contain an average of 1.2 wt. percent As. Pyrite grains are coarsely zoned, with local As concentrations ranging from approx. 0 to 5 wt. percent. Electron microprobe, transmission electron microscope, and extended X-ray absorption fine-structure spectroscopy (EXAFS) analyses indicate that As substitutes for S in pyrite and is not present as inclusions of arsenopyrite or other As-bearing phases. Comparison with simulated EXAFS spectra demonstrates that As atoms are locally clustered in the pyrite lattice and that the unit cell of arsenian pyrite is expanded by approx. 2.6 percent relative to pure pyrite. During weathering, clustered substitution of As into pyrite may be responsible for accelerating oxidation, hydrolysis, and dissolution of arsenian pyrite relative to pure pyrite in weathered tailings. Arsenic K-edge EXAFS analysis of the fine-grained Fe-rich weathering products are consistent with corner-sharing between As(V) tetrahedra and Fe(III)-octahedra. Determinations of nearest-neighbor distances and atomic identities, generated from least-squares fitting algorithms to spectral data, indicate that arsenate tetrahedra are sorbed on goethite mineral surfaces but substitute for SO4 in jarosite. Erosional transport of As-bearing goethite and jarosite to Don Pedro Reservoir increases the potential for As mobility and bioavailability by desorption or dissolution. Both the substrate minerals and dissolved As species are expected to respond to seasonal changes in lake chemistry caused by thermal stratification and turnover within the monomictic Don Pedro Reservoir. Arsenic is predicted to be most bioavailable and toxic in the reservoir's summer hypolimnion.

  4. Arsenic speciation in pyrite and secondary weathering phases, Mother Lode gold district, Tuolumne County, California

    SciTech Connect

    Savage, K.S.; Tingle, Tracy N.; O'Day, Peggy A.; Waychunas, Glenn A.; Bird, Dennis K.

    2004-10-27

    Arsenian pyrite, formed during Cretaceous gold mineralization, is the primary source of As along the Melones fault zone in the southern Mother Lode Gold District of California. Mine tailings and associated weathering products from partially submerged inactive gold mines at Don Pedro Reservoir, on the Tuolumne River, contain approx. 20-1300 ppm As. The highest concentrations are in weathering crusts from the Clio mine and nearby outcrops which contain goethite or jarosite. As is concentrated up to 2150 ppm in the fine-grained (<63 mu-m) fraction of these Fe-rich weathering products. Individual pyrite grains in albite-chlorite schists of the Clio mine tailings contain an average of 1.2 wt. percent As. Pyrite grains are coarsely zoned, with local As concentrations ranging from approx. 0 to 5 wt. percent. Electron microprobe, transmission electron microscope, and extended X-ray absorption fine-structure spectroscopy (EXAFS) analyses indicate that As substitutes for S in pyrite and is not p resent as inclusions of arsenopyrite or other As-bearing phases. Comparison with simulated EXAFS spectra demonstrates that As atoms are locally clustered in the pyrite lattice and that the unit cell of arsenian pyrite is expanded by approx. 2.6 percent relative to pure pyrite. During weathering, clustered substitution of As into pyrite may be responsible for accelerating oxidation, hydrolysis, and dissolution of arsenian pyrite relative to pure pyrite in weathered tailings. Arsenic K-edge EXAFS analysis of the fine-grained Fe-rich weathering products are consistent with corner-sharing between As(V) tetrahedra and Fe(III)-octahedra. Determinations of nearest-neighbor distances and atomic identities, generated from least-squares fitting algorithms to spectral data, indicate that arsenate tetrahedra are sorbed on goethite mineral surfaces but substitute for SO4 in jarosite. Erosional transport of As-bearing goethite and jarosite to Don Pedro Reservoir increases the potential for As mobility and bioavailability by desorption or dissolution. Both the substrate minerals and dissolved As species are expected to respond to seasonal changes in lake chemistry caused by thermal stratification and turnover within the monomictic Don Pedro Reservoir. Arsenic is predicted to be most bioavailable and toxic in the reservoir's summer hypolimnion.

  5. District energy growth

    SciTech Connect

    Seeley, R.S.

    1995-11-01

    Utility competition is heating up as utilities focus attention back to district energy after turning away from it for decades after World War II. Utilities are re-entering the district energy business by forming non-regulated district energy subsidiaries. Trigen Energy Corp., as the largest commercial owner and operator of community district energy systems in North America, defines the district heating and cooling (DHC) growth trend of systems being taken over, upgraded and expanded. These trends gather momentum with the economic attractions that have propelled DHC for the past decade and more. With DHC, a building owner worries less about maintenance and can operate with a smaller workforce for maintenance. Heating and cooling systems operate more reliably. Trigen`s Trenton plant, producing electricity, heating and cooling, recovers 66 percent of input energy - more than double the efficiency of conventional electric generation. Yet, it produces less than one-half the pollutants of conventional generation.

  6. A multiscale thermo-fluid computational model for a two-phase cooling system

    NASA Astrophysics Data System (ADS)

    Sacco, Riccardo; Carichino, Lucia; de Falco, Carlo; Verri, Maurizio; Agostini, Francesco; Gradinger, Thomas

    2014-12-01

    In this paper, we describe a mathematical model and a numerical simulation method for the condenser component of a novel two-phase thermosyphon cooling system for power electronics applications. The condenser consists of a set of roll-bonded vertically mounted fins among which air flows by either natural or forced convection. In order to deepen the understanding of the mechanisms that determine the performance of the condenser and to facilitate the further optimization of its industrial design, a multiscale approach is developed to reduce as much as possible the complexity of the simulation code while maintaining reasonable predictive accuracy. To this end, heat diffusion in the fins and its convective transport in air are modeled as 2D processes while the flow of the two-phase coolant within the fins is modeled as a 1D network of pipes. For the numerical solution of the resulting equations, a Dual Mixed-Finite Volume scheme with Exponential Fitting stabilization is used for 2D heat diffusion and convection while a Primal Mixed Finite Element discretization method with upwind stabilization is used for the 1D coolant flow. The mathematical model and the numerical method are validated through extensive simulations of realistic device structures which prove to be in excellent agreement with available experimental data.

  7. Influence of Cooling Rate on Phase Formationin Spray-Formed H13 Tool Steel

    SciTech Connect

    K. M. Mchugh; Y. Lin; Y. Zhou; E. J. Lavernia

    2006-04-01

    Spray forming is an effective way to process many tool steels into near-net-shape molds, dies and related tooling. The general approach involves depositing atomized droplets onto a refractory pattern in order to image the pattern’s features. The pattern is removed and the die is fitted into a standard holding fixture. This approach results in significant cost and lead-time savings compared to conventional machining, Spray-formed dies perform well in many industrial forming operations, oftentimes exhibiting extended die life over conventional dies. Care must be exercised when spray forming tool steel dies to minimize porosity and control the nature and distribution of phases and residual stresses. Selection of post-deposition heat treatment is important to tailor the die’s properties (hardness, strength, impact energy, etc.) for a particular application. This paper examines how the cooling rate and other processing parameters during spray processing and heat treatment of H13 tool steel influence phase formation. Results of case studies on spray-formed die performance in forging, extrusion and die casting, conducted by industry during production runs, will be described.

  8. Urban thermal environment measurements and numerical simulation for an actual complex urban area covering a large district heating and cooling system in summer

    NASA Astrophysics Data System (ADS)

    Huang, Hong; Ooka, Ryozo; Kato, Shinsuke

    Urban thermal situation is thought to have a great influence on the air quality in urban areas. In recent years, the urban thermal environment has become worse, such as the days on which the temperature goes above 30 C, the sultry nights and heat stroke increase due to changes in terrestrial cover and increased anthropogenic heat emission accompanied by urbanization. Therefore, the urban thermal environment should be carefully investigated and accurately analyzed for a better study of the air quality. Here, in order to study the urban thermal environment in summer, (1) the actual status of an urban thermal environment in a complex urban area covering a large district heating and cooling (DHC) system in Tokyo is investigated using field measurements, and (2) a numerical simulation program which can be adapted to complex urban areas coupled with convection, radiation and conduction is developed and used to predict the urban thermal environment. Wind velocity, temperature and humidity are obtained from the simulation, which shows good agreement with results of the field measurement. The spatial distribution of the standard effective temperature (SET *), the comprehensive index of human thermal comfort, is also calculated using the above results, to estimate the thermal comfort at the pedestrian level. This urban thermal numerical simulation can be coupled with air pollution dispersion and chemical processes to provide a more precise air quality prediction in complex urban areas.

  9. Effect of rapid slight cooling of the skin in various phases of immunogenesis on the immune response.

    PubMed

    Kozyreva, T V; Eliseeva, L S; Tsoi, L V; Khramova, G M

    2006-10-01

    Slight cooling had no effect on heat emission and heat production, but modulated the immune response to antigen in animals. Changes in the immune response upon rapid slight cooling of the skin (by 1.5 degrees C) depended on the phase of immunogenesis corresponding to cold exposure. When cooling was performed immediately after immunization, antibody production increased in the spleen and blood, while antigen binding in the spleen remained unchanged. Cold exposure on day 5 after antigen treatment as well as immunization at the peak of cooling did not modulate antibody production, but increased antigen binding in the spleen. Our findings attest to an important role of the temperature factor in the formation of the immune response, which should be taken into account during vaccination. PMID:17415423

  10. Coupled Analysis of Change in Fracture Permeability during the Cooling Phase of the Yucca Mountain Drift Scale Test

    SciTech Connect

    Rutqvist, Jonny; Rutqvist, J.; Freifeld, B.; Tsang, Y.W.; Min, K.B.; Elsworth, D.

    2008-06-01

    This paper presents results from a coupled thermal, hydrological and mechanical analysis of thermally-induced permeability changes during heating and cooling of fractured volcanic rock at the Drift Scale Test at Yucca Mountain, Nevada. The analysis extends the previous analysis of the four-year heating phase to include newly available data from the subsequent four year cooling phase. The new analysis of the cooling phase shows that the measured changes in fracture permeability follows that of a thermo-hydro-elastic model on average, but at several locations the measured permeability indicates (inelastic) irreversible behavior. At the end of the cooling phase, the air-permeability had decreased at some locations (to as low as 0.2 of initial), whereas it had increased at other locations (to as high as 1.8 of initial). Our analysis shows that such irreversible changes in fracture permeability are consistent with either inelastic fracture shear dilation (where permeability increased) or inelastic fracture surface asperity shortening (where permeability decreased). These data are important for bounding model predictions of potential thermally-induced changes in rock-mass permeability at a future repository at Yucca Mountain.

  11. The study of a reactor cooling pump under two-phase flow

    NASA Astrophysics Data System (ADS)

    Wang, P.; Yuan, S. Q.; Wang, X. L.; Zhang, F.

    2015-01-01

    In this paper, the steady pressure field has been investigated numerically by computational fluid dynamics (CFD) in a nuclear reactor cooling pump. As a multiphase approach the Eulerian-Eulerian two fluid model has been applied to calculated five computational models with different kinds of blades. The analysis of inner flow field of the five model pumps shows that the pressure in the impeller increases with the increase of the gas contents and the pressure distributions are irregular at the inlet of different blades when the gas contents less than 20%. With the increase of the number of blades, the vortexes at the outlet of impeller decrease whereas the vortexes in the deep of the volute markedly increases and high velocity of the fluid huddle is generated gradually at the outlet pipes. Under the action of centrifugal force and Coriolis force, gas phase mainly concentrated at the lower velocity and lower pressure area. The radial force on the impeller gradually increases with the increase of the gas contents.

  12. Performance study of a thermal-envelope house: Phase II. Cooling performance. Final report

    SciTech Connect

    Akridge, J. M.; Benton, C. C.

    1981-01-01

    The thermal envelope house is shown to perform much better than conventional houses without mechanical refrigeration and better than one would expect from most passively cooled houses in the hot-humid climate of Georgia. Peak temperatures inside the house were 8 to 15/sup 0/F below peak ambient temperatures. Peak inside temperature measured during the test period was 80/sup 0/F with an outside ambient peak of 93/sup 0/F. Air flow rates within the envelope were less than 1 ft/sec even when the attic fan was operating. The earth cooling tubes provided noticeable sensible cooling to the house. Exit temperatures from the cooling tubes were between 72 to 76/sup 0/F, depending upon the air velocity through the tubes. The thermal chimney performed poorly as an air mover, especially when used to induce flow through the earth cooling tubes. The performance of the earth cooling tube could be improved by using the attic fan to increase the air flow through the cooling tubes and to insure it flowed in the cooling tube, through the envelope and out the thermal chimney. Being an exhaust fan, the attic fan created a negative pressure in the house. While this increased air flow through the cooling tubes, it also increased air infiltration through the building shell, thus increasing load. The humidity level within the living space remains relatively high year-round due to low rates of air infiltration and water vapor transmission through the building skin. The problem is aggravated during the summer by the introduction of cool moist air from the cooling tubes to the envelope and frequently to the inner space. While the cooling tubes are able to reduce the sensible load, and they are incapable of significantly reducing humidity or latent loads. This results in relatively comfortable air temperatures but uncomfortable humidities within the living space.

  13. Demonstration of Super Cooled Ice as a Phase Change Material Heat Sink for Portable Life Support Systems

    NASA Technical Reports Server (NTRS)

    Leimkuehler, Thomas O.; Bue, Grant C.

    2009-01-01

    A phase change material (PCM) heat sink using super cooled ice as a nontoxic, nonflammable PCM is being developed. The latent heat of fusion for water is approximately 70% larger than most paraffin waxes, which can provide significant mass savings. Further mass reduction is accomplished by super cooling the ice significantly below its freezing temperature for additional sensible heat storage. Expansion and contraction of the water as it freezes and melts is accommodated with the use of flexible bag and foam materials. A demonstrator unit has been designed, built, and tested to demonstrate proof of concept. Both testing and modeling results are presented along with recommendations for further development of this technology.

  14. Solar Heating and Cooling of Buildings: Phase 0. Executive Summary. Final Report.

    ERIC Educational Resources Information Center

    Westinghouse Electric Corp., Baltimore, MD.

    After the Westinghouse Electric Corporation made a comprehensive analysis of the technical, economic, social, environmental, and institutional factors affecting the feasibility of utilizing solar energy for heating and cooling buildings, it determined that solar heating and cooling systems can become competitive in most regions of the country in…

  15. Solar Heating and Cooling of Buildings (Phase O). Volume 1: Executive Summary.

    ERIC Educational Resources Information Center

    TRW Systems Group, Redondo Beach, CA.

    The purpose of this study was to establish the technical and economic feasibility of using solar energy for the heating and cooling of buildings. Five selected building types in 14 selected cities were used to determine loads for space heating, space cooling and dehumidification, and domestic service hot water heating. Relying on existing and…

  16. In vivo MRI using liquid nitrogen cooled phased array coil at 3.0 T

    PubMed Central

    Kwok, Wingchi E.; You, Zhigang

    2010-01-01

    A liquid nitrogen (LN2) cooled dual-channel array coil was designed and built for use on a 3.0-T whole-body scanner. In vivo imaging of a volunteer's fingers and imaging of a deceased mouse and oil phantom were performed using the LN2 cooled array and a similar room-temperature coil. Imaging results showed that the LN2 cooled array provides a signal-to-noise ratio gain of up to 240% as compared with its room-temperature counterpart. LN2 cooled arrays may be useful for high-resolution clinical imaging of joints, skin, eyes and peripheral vessels as well as for biomedical imaging of small animals in human disease modeling. PMID:16824977

  17. Sildenafil increases digital skin blood flow during all phases of local cooling in primary Raynaud's phenomenon

    PubMed Central

    Roustit, Matthieu; Hellmann, Marcin; Cracowski, Claire; Blaise, Sophie; Cracowski, Jean-Luc

    2012-01-01

    Digital skin vasoconstriction on local cooling is exaggerated in primary Raynaud’s phenomenon (RP) compared to controls. A significant part of such vasoconstriction relies on the nitric oxide (NO) pathway inhibition. We tested the effect of PDE5 inhibitor sildenafil, which potentiates the effect of NO, on skin blood flow. We recruited 15 patients with primary RP, performing local cooling without sildenafil (day 1), after a single 50 mg oral dose (day 2), and 100 mg (day 3). Skin blood flow, skin temperature and arterial pressure were recorded, and data were expressed as cutaneous vascular conductance (CVC). Sildenafil at 100 mg, but not 50 mg, significantly lessened the cooling-induced decrease in CVC. It also increased resting CVC and skin temperature. These data suggest that 100 mg sildenafil improves digital skin blood flow to local cooling in primary RP. The benefit of sildenafil “as required” should be confirmed in a randomized controlled trial. PMID:22453196

  18. Implementation of a Proficiency-Based Diploma System in Maine: Phase II--District Level Analysis

    ERIC Educational Resources Information Center

    Silvernail, David L.; Stump, Erika K.; McCafferty, Anita Stewart; Hawes, Kathryn M.

    2014-01-01

    This report describes the findings from Phase II of a study of Maine's implementation of a proficiency-based diploma system. At the request of the Joint Standing Committee on Education and Cultural Affairs of the Maine Legislature, the Maine Policy Research Institute (MEPRI) has conducted a two-phased study of the implementation of Maine law…

  19. The partitioning of copper among selected phases of geologic media of two porphyry copper districts, Puerto Rico

    USGS Publications Warehouse

    Learned, R.E.; Chao, T.T.; Sanzolone, R.F.

    1981-01-01

    In experiments designed to determine the manner in which copper is partitioned among selected phases that constitute geologic media, we have applied the five-step sequential extraction procedure of Chao and Theobald to the analysis of drill core, soils, and stream sediments of the Rio Vivi and Rio Tanama porphyry copper districts of Puerto Rico. The extraction procedure affords a convenient means of determining the trace-metal content of the following fractions: (1) Mn oxides and "reactive" Fe oxides; (2) "amorphous" Fe oxides; (3) "crystalline" Fe oxides; (4) sulfides and magnetite; and (5) silicates. An additional extraction between steps (1) and (2) was performed to determine organic-related copper in stream sediments. The experimental results indicate that apportionment of copper among phases constituting geologic media is a function of geochemical environment. Distinctive partitioning patterns were derived from the analysis of drill core from each of three geochemical zones: (a) the supergene zone of oxidation; (b) the supergene zone of enrichment; and (c) the hypogene zone; and similarly, from the analysis of; (d) soils on a weakly leached capping; (e) soils on a strongly leached capping; and (f) active stream sediment. The experimental results also show that geochemical contrasts (anomaly-to-background ratios) vary widely among the five fractions of each sampling medium investigated, and that at least one fraction of each medium provides substantially stronger contrast than does the bulk medium. Fraction (1) provides optimal contrast for stream sediments of the district; fraction (2) provides optimal contrast for soils on a weakly leached capping; fraction (3) provides optimal contrast for soils on a strongly leached capping. Selective extraction procedures appear to have important applications to the orientation and interpretive stages of geochemical exploration. Further investigation and testing of a similar nature are recommended. ?? 1981.

  20. On the theory of the conversion of metallic mixed phases. 5: Fluctuations and nucleation in sub-cooled phases

    NASA Technical Reports Server (NTRS)

    Borelius, G.

    1988-01-01

    A comparison is made between fluctuation-theoretical calculations and empirical results. Concentration fluctuations and the resulting separation, and the distribution function of the reversible fluctuations are approximately calculated. The relation of this distribution to the concentration-dependence of the free energy is discussed. Possible effects of fluctuations are discussed, and other attempts to explain the sub-cooling are described.

  1. Three phases of cooling and unroofing in the Appalachian Basin, Pennsylvania: Implications for flexural control

    SciTech Connect

    Blackmer, G.C.; Gold, D.P. . Dept. of Geosciences); Omar, G.I. . Geology Dept.)

    1992-01-01

    Apatite fission-track ages of 111--184 Ma and mean lengths of 10.7--13.1 [mu]m with unimodal, negatively skewed length distributions indicate slow cooling of Ordovician through Permian rocks in an area extending from the Anthracite Basin to the western Appalachian Plateau. Cooling histories modeled from fission-track data show that cooling began immediately following the Alleghanian Orogeny at 250--240 Ma. Ordovician rocks in the Juniata Culmination began to cool slightly earlier at 265 Ma, probably reflecting synorogenic unroofing of this area during formation of the Valley and Ridge duplex. Unroofing histories were modeled from cooling histories using the one-dimensional heat flow equation. Cooling and unroofing histories can be divided into three periods. The initial period of relatively rapid cooling and unroofing extended from the end of the Alleghanian Orogeny into the Jurassic and represents post-orogenic unroofing due to flexural rebound as orogenic load was removed through erosion. Initial unroofing rates are higher in eater Pennsylvania than in the west, consistent with a flexural model. A period of little to no unroofing from the Jurassic into the Miocene began contemporaneously with the inception of drift at the Atlantic continental margin. As the new continental margin subsided, the remaining load dropped below sea level and was no longer subject to removal, resulting in the cessation of flexural rebound and suppression of unroofing in the foreland. The most rapid unroofing occurred from the Miocene to the present. The nature of this event is unknown; however, it is also observed in increased sedimentation rates in the middle Atlantic offshore basins.

  2. Streamflow changes in Alaska between the cool phase (1947-1976) and the warm phase (1977-2006) of the Pacific Decadal Oscillation: The influence of glaciers

    USGS Publications Warehouse

    Hodgkins, Glenn A.

    2009-01-01

    Streamflow data from 35 stations in and near Alaska were analyzed for changes between the cool phase (1947-1976) and the warm phase (1977-2006) of the Pacific Decadal Oscillation. Winter, spring, and summer flow changes and maximum annual flow changes were different for glaciated basins (more than 10% glacier-covered area) than for nonglaciated basins, showing the influence of glaciers on historical streamflowchanges. Mean February flows, for example, increased for the median of available stations by 45% for glaciated basins and by 17% for nonglaciated ones.

  3. Collaborating To Serve Arizona Students & Families More Effectively: Phase 1 Report. Evaluation of Murphy School District-Department of Economic Security Collaborative Project.

    ERIC Educational Resources Information Center

    Izu, Jo Ann; Carreon, Tori

    This report presents the results of Phase I of an evaluation of the Murphy School District (MSD)-Department of Economic Security (DES) collaborative effort, one of the first interagency partnerships in the state of Arizona that attempts to address the needs of students and their families more effectively. The primary purposes of the evaluation are…

  4. Optimized He 2 cooling systems for space application. Behavior and handling of superfluid helium at G = 0, phase 1

    NASA Astrophysics Data System (ADS)

    Denner, H. D.; Klipping, G.; Lueders, K.; Schotte, K. D.; Schotte, U.; Szuecs, Z.; Ruppert, U.

    1983-06-01

    Increased reliability of He2 cooling systems for space applications is considered. An active phase separator (APS) with annular flow gap of variable length which allows variation of the cooling capacity over a wide range, developed for zero-g tests is described. Helium-tight electrical leadthroughs, a displacement transducer for low temperature application, a ball closure for use in combination with the APS, and gas/liquid detectors were developed. For temperature and liquid level measurement in narrow slits in laboratory as well as flight experiments, temperature sensors were developed. Three thickness measurement methods for He2 films are proposed: optical (1/10 000 to 1/100 mm), crystal (1/10 to the 7th power to 1/10 mm) and capacitive (1/10 to the 6th power to some mm).

  5. Mathematical Model of Two Phase Flow in Natural Draft Wet-Cooling Tower Including Flue Gas Injection

    NASA Astrophysics Data System (ADS)

    Hyhlík, Tomáš

    2016-03-01

    The previously developed model of natural draft wet-cooling tower flow, heat and mass transfer is extended to be able to take into account the flow of supersaturated moist air. The two phase flow model is based on void fraction of gas phase which is included in the governing equations. Homogeneous equilibrium model, where the two phases are well mixed and have the same velocity, is used. The effect of flue gas injection is included into the developed mathematical model by using source terms in governing equations and by using momentum flux coefficient and kinetic energy flux coefficient. Heat and mass transfer in the fill zone is described by the system of ordinary differential equations, where the mass transfer is represented by measured fill Merkel number and heat transfer is calculated using prescribed Lewis factor.

  6. Liquid-Liquid Phase Transition and Its Phase Diagram in Deeply-Cooled Heavy Water Confined in a Nanoporous Silica Matrix.

    PubMed

    Wang, Zhe; Ito, Kanae; Leão, Juscelino B; Harriger, Leland; Liu, Yun; Chen, Sow-Hsin

    2015-06-01

    Using neutron diffraction technique, we measure the average density of the heavy water confined in a nanoporous silica matrix, MCM-41, over the pressure-temperature plane. The result suggests the existence of a line of liquid-liquid phase transition with its end point at 1.29 ± 0.34 kbar and 213 ± 3 K in a fully hydrated sample. This point would be the liquid-liquid critical point (LLCP) according to the "liquid-liquid critical point" scenario. The phase diagram of the deeply cooled confined heavy water is then discussed. Moreover, in a partially hydrated sample, the phase transition completely disappears. This result shows that it is the free water part, rather than the bound water part, of the confined water that undergoes a liquid-liquid transition. PMID:26266493

  7. Ice pack heat sink subsystem, phase 2. [astronaut life support cooling system

    NASA Technical Reports Server (NTRS)

    Roebelen, G. J., Jr.; Kellner, J. D.

    1975-01-01

    The report describes the design, development, fabrication, and test at one gravity of a prototype ice pack heat sink subsystem to be used eventually for astronaut cooling during manned space missions; the investigation of thermal storage material with the objective of uncovering materials with heats of fusion and/or solution in the range of 300 Btu/lb (700 kilojoules/kilogram); and the planned procedure for implementing an ice pack heat sink subsystem flight experiment. In normal use, excess heat in the liquid cooling garment (LCG) coolant is transferred to a reusable/regenerable ice pack heat sink. For emergency operation, or for extension of extravehicular activity mission time after all the ice has melted, water from the ice pack is boiled to vacuum, thereby continuing to remove heat from the LCG coolant. This subsystem incorporates a quick disconnect thermal interface between the ice pack heat sink and the subsystem heat exchanger.

  8. Binary ice, a novel technique for high performance phase change cooling

    SciTech Connect

    Kristiansen, H.; Apsimon, R.

    1997-07-01

    The cooling of a silicon tracker at the CERN Large Hadron Collider (LHC) is a demanding task. The silicon tracker has to operate at a temperature below 0 C. The small temperature gradients allowed in the tracker volume, as well as the small liquid flow rates allowed, makes the exploitable heat capacity of water marginal. The use of a Binary-Ice{reg{underscore}sign} cooling system is an attempt to address this problem. With the use of a Binary-Ice suspension, a significant improvement in temperature uniformity along a homogeneously heated tube has been observed compared to that of liquid only. This improved uniformity is caused partly by a significantly reduced temperature build-up in the bulk liquid, attributed to the absorbed heat of melting. In addition, the presence of the ice crystals causes the heat transfer coefficient to be superior to similar coolants without ice where the heat transfer coefficient is calculated from the mean liquid temperature.

  9. Analysis of the solar powered/fuel assisted Rankine cycle cooling system. Phase 1: Revision

    NASA Astrophysics Data System (ADS)

    Lior, N.; Koai, K.; Yeh, H.

    1985-04-01

    The subject of this analysis is a solar cooling system which consists of a conventional open-compressor chiller, driven by a novel hybrid steam Rankine cycle. Steam is generated by the use of solar energy collected at about 100C, and it is then superheated to about 600C in a fossil-fuel fired superheater. The steam drives a novel counter-rotating turbine, some of the heat from it is regenerated, and it is then condensed. Thermal storage is implemented as an integral part of the cycle, by means of hot-water which is flashed to steam when needed for driving the turbine. For the solar energy input, both evacuated and double-glazed flat-plate collectors were considered. A comprehensive computer program was developed to analyze the operation and performance of the entire power/cooling system. Each component was described by a separate subroutine to compute its performance from basic principles, and special attention was given to the parasitic losses, including pumps, fans and pressure drops in the piping and heat exchangers, and to describe the off-design performance of the components. The thermophysical properties of the fluids used are also described in separate subroutines. Transient simulation of the entire system was performed on an hourly basis over a cooling season in two representative climatic regions (Washington, DC, and Phoenix, AZ) for a number of system configurations.

  10. Liquid hot NAGMA cooled to 0.4 K: benchmark thermochemistry of a gas-phase peptide.

    PubMed

    Leavitt, Christopher M; Moore, Kevin B; Raston, Paul L; Agarwal, Jay; Moody, Grant H; Shirley, Caitlyne C; Schaefer, Henry F; Douberly, Gary E

    2014-10-16

    Vibrational spectroscopy and helium nanodroplet isolation are used to determine the gas-phase thermochemistry for isomerization between conformations of the model dipeptide, N-acetylglycine methylamide (NAGMA). A two-stage oven source is implemented to produce a gas-phase equilibrium distribution of NAGMA conformers, which is preserved when individual molecules are captured and cooled to 0.4 K by He nanodroplets. With polarization spectroscopy, the IR spectrum in the NH stretch region is assigned to a mixture of two conformers having intramolecular hydrogen bonds composed of either five- or seven-membered rings, C5 and C7, respectively. The C5 to C7 interconversion enthalpy and entropy, obtained from a van't Hoff analysis, are -4.52 ± 0.12 kJ/mol and -12.4 ± 0.2 J/(mol · K), respectively. The experimental thermochemistry is compared to high-level electronic structure theory computations. PMID:25244309

  11. Computation of Phase Fractions in Austenite Transformation with the Dilation Curve for Various Cooling Regimens in Continuous Casting

    NASA Astrophysics Data System (ADS)

    Dong, Zhihua; Chen, Dengfu; Long, Mujun; Li, Wei; Chen, Huabiao; Vitos, Levente

    2016-03-01

    A concise model is applied to compute the microstructure evolution of austenite transformation by using the dilation curve of continuously cast steels. The model is verified by thermodynamic calculations and microstructure examinations. When applying the model, the phase fractions and the corresponding transforming rates during austenite transformation are investigated at various cooling rates and chemical compositions. In addition, ab initio calculations are performed for paramagnetic body-centered-cubic Fe to understand the thermal expansion behavior of steels at an atomic scale. Results indicate that by increasing the cooling rate, the final volume fraction of ferrite/pearlite will gradually increase/decrease with a greater transforming rate of ferrite. The ferrite fraction increases after austenite transformation with lowering of the carbon content and increasing of the substitutional alloying fractions. In the austenite transformation, the thermal expansion coefficient is sequentially determined by the forming rate of ferrite and pearlite. According to the ab initio theoretical calculations for the single phase of ferrite, thermal expansion emerges from magnetic evolution and lattice vibration, the latter playing the dominant role. The theoretical predictions for volume and thermal expansion coefficient are in good agreement with the experimental data.

  12. Open cycle heat pump development for local resource use Phase II district heating case study analysis: Progress report, 1 January 1989--30 March 1989

    SciTech Connect

    DiBella, F.; Becker, F.E.; Glick, J.

    1989-05-01

    A district heating system is proposed that uses low-level waste- energy sources, and a quasi open-cycle steam heat pump as a means of upgrading the energy in the form of hot water to use as a transport medium in the system. the use of a water-based, open-cycle heat pump appears to be extremely well suited in terms of its potential thermodynamic performance, cost, and environmental safety compared to more typical organic gased closed cycle systems. The Phase II case study provides a detailed analysis of a district heating system that utilizes the open cycle steam heat pump concept developed in Phase I. This quarterly report describes the energy audit performed on the heat source and heat sink.

  13. Gas-phase measurements of combustion interaction with materials for radiation-cooled chambers

    NASA Technical Reports Server (NTRS)

    Barlow, R. S.; Lucht, R. P.; Jassowski, D. M.; Rosenberg, S. D.

    1991-01-01

    Foil samples of Ir and Pt are exposed to combustion products in a controlled premixed environment at atmospheric pressure. Electrical heating of the foil samples is used to control the surface temperature and to elevate it above the radiative equilibrium temperature within the test apparatus. Profiles of temperature and OH concentration in the boundary layer adjacent to the specimen surface are measured by laser-induced fluorescence. Measured OH concentrations are significantly higher than equilibrium concentrations calculated for the known mixture ratio and the measured temperature profiles. This result indicates that superequilibrium concentrations of H-atoms and O-atoms are also present in the boundary layer, due to partial equilibrium of the rapid binary reactions of the H2/O2 chemical kinetic system. These experiments are conducted as part of a research program to investigate fundamental aspects of the interaction of combustion gases with advanced high-temperature materials for radiation-cooled thrusters.

  14. The Two Missing Conformers of Gas-Phase Alanine: a Jet-Cooled Raman Spectroscopy Study

    NASA Astrophysics Data System (ADS)

    Balabin, Roman M.

    2010-06-01

    The jet-cooled spontaneous Raman spectrum of an amino acid -- alanine (Ala, 2-aminopropanoic acid; H_2NCH(CH_3)COOH) -- is reported. The low-frequency vibrational spectrum (below 500 cm-1) was recorded and assigned using quantum chemical data: ab initio (MP2) and density functional theory (DFT; BLYP, B3LYP, and PBE0/PBE1PBE). Band polarization measurements were used to confirm the vibrational assignments. The acquired medium resolution spectra (HWHM of approximately 4 cm-1) allow the different alanine conformations to be distinguished. Four alanine conformers were observed and identified: two previously reported by microwave (MW) spectroscopy studies and two that were previously unreported. A set of reasons for why these conformers eluded previous studies are discussed. Selective collisional relaxation processes in the jet (associated with low interconversion barriers between different alanine conformations) that depopulate the high-energy conformers were experimentally demonstrated. Conclusions about conformational equilibrium in peptide/protein building block are made.

  15. Studies of Phase Change Materials and a Latent Heat Storage Unit Used for a Natural Circulation Cooling/Latent Heat Storage System

    NASA Astrophysics Data System (ADS)

    Sakitani, Katsumi; Honda, Hiroshi

    Experiments were performed to investigate feasibility of using organic materials as a PCM for a latent heat storage unit of a natural circulation cooling/latent heat storage system. This system was designed to cool a shelter accommodating telecommunication equipment located in subtropical deserts or similar regions without using a power source. Taking into account practical considerations and the results of various experiments regarding the thermodynamic properties, thermal degradation, and corrosiveness to metals, lauric acid and iron was selected for the PCM and the latent heat storage unit material, respectively. Cyclic heating and cooling of the latent heat storage unit undergoing solid-liquid phase change was repeated for more than 430 days. The results showed that the heating-cooling curve was almost unchanged between the early stage and the 1,870th cycle. It was concluded that the latent heat storage unit could be used safely for more than ten years as a component of the cooling system.

  16. Phase modulation for reduced vibration sensitivity in laser-cooled clocks in space

    NASA Technical Reports Server (NTRS)

    Klipstein, W.; Dick, G.; Jefferts, S.; Walls, F.

    2001-01-01

    The standard interrogation technique in atomic beam clocks is square-wave frequency modulation (SWFM), which suffers a first order sensitivity to vibrations as changes in the transit time of the atoms translates to perceived frequency errors. Square-wave phase modulation (SWPM) interrogation eliminates sensitivity to this noise.

  17. Phase II Testing of Liquid Cooling Garments Using a Sweating Manikin, Controlled by a Human Physiological Model

    NASA Technical Reports Server (NTRS)

    Paul, Heather; Trevino, Luis; Bue,Grant; Rugh, John

    2006-01-01

    An Advanced Automotive Manikin (ADAM) developed at the National Renewable Energy Laboratory (NREL) is used to evaluate NASA's liquid cooling garments (LCGs) used in advanced space suits for extravehicular applications. The manikin has 120 separate heated/sweating zones and is controlled by a finite element physiological model of the human thermoregulatory system. Previous testing showed the thermal sensation and comfort followed the expected trends as the LCG inlet fluid temperature was changed. The Phase II test data demonstrates the repeatability of ADAM by retesting the baseline LCG. Skin and core temperature predictions using ADAM in an LCG/Arctic suit combination are compared to NASA physiological data to validate the manikin/model. Additional LCG configurations are assessed using the manikin and compared to the baseline LCG. Results can extend to other personal protective clothing, including HAZMAT suits, nuclear/biological/chemical protective suits, and fire protection suits.

  18. Monitoring peak power and cooling energy savings of shade trees and white surfaces in the Sacramento Municipal Utility District (SMUD) service area: Project design and preliminary results

    SciTech Connect

    Akbari, H.; Bretz, S.; Hanford, J.; Rosenfeld, A.; Sailor, D.; Taha, H.; Bos, W.

    1992-12-01

    Urban areas in warm climates create summer heat islands of daily average intensity of 3--5{degrees}C, adding to discomfort and increasing air-conditioning loads. Two important factors contributing to urban heat islands are reductions in albedo (lower overall city reflectance) and loss of vegetation (less evapotranspiration). Reducing summer heat islands by planting vegetation (shade trees) and increasing surface albedos, saves cooling energy, allows down-sizing of air conditioners, lowers air-conditioning peak demand, and reduces the emission of CO{sub 2} and other pollutants from electric power plants. The focus of this multi-year project, jointly sponsored by SMUD and the California Institute for Energy Efficiency (CIEE), was to measure the direct cooling effects of trees and white surfaces (mainly roofs) in a few buildings in Sacramento. The first-year project was to design the experiment and obtain base case data. We also obtained limited post retrofit data for some sites. This report provides an overview of the project activities during the first year at six sites. The measurement period for some of the sites was limited to September and October, which are transitional cooling months in Sacramento and hence the interpretation of results only apply to this period. In one house, recoating the dark roof with a high-albedo coating rendered air conditioning unnecessary for the month of September (possible savings of up to 10 kWh per day and 2 kW of non-coincidental peak power). Savings of 50% relative to an identical base case bungalow were achieved when a school bungalow`s roof and southeast wall were coated with a high-albedo coating during the same period. Our measured data for the vegetation sites do not indicate conclusive results because shade trees were small and the cooling period was almost over. We need to collect more data over a longer cooling season in order to demonstrate savings conclusively.

  19. Cooling field tuned magnetic phase transition and exchange bias-like effect in Y0.9Pr0.1CrO3

    NASA Astrophysics Data System (ADS)

    Deng, Dongmei; Zheng, Jiashun; Yu, Dehong; Wang, Baomin; Sun, Dehui; Avdeev, Maxim; Feng, Zhenjie; Jing, Chao; Lu, Bo; Ren, Wei; Cao, Shixun; Zhang, Jincang

    2015-09-01

    Cooling magnetic field dependence of magnetic phase transition has been observed in Y0.9Pr0.1CrO3. GzFx order (spin structure of PrCrO3) is dominant after zero field cooling (ZFC), whereas GxFz order (spin structure of YCrO3) is dominant after cooling under a field higher than 100 Oe. Positive/negative exchange bias-like effect, with large vertical shift and small horizontal shift, has been observed after FC/ZFC process. The vertical shift can be attributed to the frozen ordered Pr3+ and Cr3+ spins in magnetic domains, because of the strong coupling between Pr3+ and Cr3+ sublattices; while the horizontal shift is a result of the pinning of spins at the interfaces. The frozen structure is generated by the field used for the measurement of the initial magnetization curve of M(H) for the ZFC cooled sample, while it is generated by the cooling field for the sample cooled under a cooling field higher than 100 Oe.

  20. Stability and Phase Noise Tests of Two Cryo-Cooled Sapphire Oscillators

    NASA Technical Reports Server (NTRS)

    Dick, G. John; Wang, Rabi T.

    1998-01-01

    A cryocooled Compensated Sapphire Oscillator (CSO), developed for the Cassini Ka-band Radio Science experiment, and operating in the 8K - 10K temperature range was previously demonstrated to show ultra-high stability of sigma(sub y) = 2.5 x 10 (exp -15) for measuring times 200 seconds less than or equal to tau less than or equal to 600 seconds using a hydrogen maser as reference. We present here test results for a second unit which allows CSO short-term stability and phase noise to be measured for the first time. Also included are design details of a new RF receiver and an intercomparison with the first CSO unit. Cryogenic oscillators operating below about 10K offer the highest possible short term stability of any frequency sources. However, their use has so far been restricted to research environments due to the limited operating periods associated with liquid helium consumption. The cryocooled CSO is being built in support of the Cassini Ka-band Radio Science experiment and is designed to operate continuously for periods of a year or more. Performance targets are a stability of 3-4 x 10 (exp -15) (1 second less than or equal to tau less than or equal to 100 seconds) and phase noise of -73dB/Hz @ 1Hz measured at 34 GHz. Installation in 5 stations of NASA's deep space network (DSN) is planned in the years 2000 - 2002. In the previous tests, actual stability of the CSO for measuring times tau less than or equal to 200 seconds could not be directly measured, being masked by short-term fluctuations of the H-maser reference. Excellent short-term performance, however, could be inferred by the success of an application of the CSO as local oscillator (L.O.) to the JPL LITS passive atomic standard, where medium-term stability showed no degradation due to L.O. instabilities at a level of (sigma)y = 3 x 10 (exp -14)/square root of tau. A second CSO has now been constructed, and all cryogenic aspects have been verified, including a resonator turn-over temperature of 7.907 K, and Q of 7.4 x 10 (exp 8). These values compare to a turn-over of 8.821 K and Q of 1.0 x 10 (exp 9) for the first resonator. Operation of this second unit provides a capability to directly verify for the first time the short-term (1 second less than or equal to tau less than or equal to 200 seconds) stability and the phase noise of the CSO units. The RF receiver used in earlier tests was sufficient to meet Cassini requirements for tau greater than or equal to 10 seconds but had short-term stability limited to 2-4 x 10 (exp -14) at tau = 1 second, a value 10 times too high to meet our requirements. A new low-noise receiver has been designed to provide approximately equal to 10-15 performance at 1 second, and one receiver is now operational, demonstrating again short-term CSO performance with H maser-limited stability. Short-term performance was degraded in the old receiver due to insufficient tuning bandwidth in a 100MHZ quartz VCO that was frequency-locked to the cryogenic sapphire resonator. The new receivers are designed for sufficient bandwidth, loop gain and low noise to achieve the required performance.

  1. Emerging cool white light emission from Dy(3+) doped single phase alkaline earth niobate phosphors for indoor lighting applications.

    PubMed

    Vishwakarma, Amit K; Jha, Kaushal; Jayasimhadri, M; Sivaiah, B; Gahtori, Bhasker; Haranath, D

    2015-10-21

    Single-phase cool white-light emitting BaNb2O6:Dy(3+) phosphors have been synthesized via a conventional solid-state reaction method and characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) observations and spectrofluorophotometric measurements. XRD and Rietveld structural refinement studies confirm that all the samples exhibit pure orthorhombic structure [space group -C2221(20)]. SEM observations reveal the dense particle packaging with irregular morphology in a micron range. The as-prepared phosphors exhibit blue (482 nm) and yellow (574 nm) emissions under 349, 364, 386 and 399 nm excitations corresponding to (4)F9/2→(6)HJ (J = 15/2, 13/2) transitions of Dy(3+) ions. The energy transfer mechanism between Dy(3+) ions has been studied in detail and the luminescence decay lifetime for the (4)F9/2 level was found to be around 146.07 μs for the optimized phosphor composition. The calculated Commission Internationale de L'Eclairage (CIE) chromaticity coordinates for the optimized phosphor are (x = 0.322, y = 0.339), which are close to the National Television Standard Committee (NTSC) (x = 0.310, y = 0.316) coordinates. The values of CIE chromaticity coordinates and correlated color temperature (CCT) of 5907 K endorse cool white-light emission from the phosphor. The study reveals that BaNb2O6:Dy(3+) phosphor could be a potential candidate for near ultra-violet (NUV) excited white-LED applications. PMID:26374377

  2. Research, development and demonstration needs of district heating technology. Final report

    SciTech Connect

    Gleason, T.C.J.

    1983-11-01

    The following chapters are included: end use technologies for district heating and cooling (DHC); district heating and cooling distribution systems; cogeneration technologies for DHC; industrial waste heat utilization for district heating; biomass fuels for use in cogeneration and heat production for DHC; solar district heating: first generation technologies; R and D needs in solar collector technology for use with interseasonal thermal storage and district heating systems; and the use of heat pumps in low temperatures district heating systems. (MHR)

  3. Determination of organochlorine pesticides in water using solvent cooling assisted dynamic hollow-fiber-supported headspace liquid-phase microextraction.

    PubMed

    Huang, Shih-Pin; Huang, Shang-Da

    2007-12-28

    The organic solvent film formed within a hollow fiber was used as an extraction interface in the headspace liquid-phase microextraction (HS-LPME) of organochlorine pesticides. Some common organic solvents with different vapor pressures (9.33-12,918.9 Pa) were studied as extractants. The results indicated that even the solvent with the highest vapor pressure (cyclohexane) can be used to carry out the extraction successfully. However, those compounds (analytes) with low vapor pressures could not be extracted successfully. In general, the large surface area of the hollow fiber can hasten the extraction speed, but it can increase the risk of solvent loss. Lowering the temperature of the extraction solvent could not only reduce solvent loss (by lowering its vapor pressure) but also extend the feasible extraction time to improve extraction efficiency. In this work, a solvent cooling assisted dynamic hollow-fiber-supported headspace liquid-phase microextraction (SC-DHF-HS-LPME) approach was developed. By lowering the temperature of the solvent, the evaporation can be decreased, the extraction time can be lengthened, and, on the contrary, the equilibrium constant between headspace phase and extraction solvent can be increased. In dynamic LPME, the extracting solvent is held within a hollow fiber, affixed to a syringe needle and placed in the headspace of the sample container. The extracting solvent within the fiber is moved to-and-fro by using a programmable syringe pump. The movement facilitates mass transfer of analyte(s) from the sample to the solvent. Analysis of the extract was carried out by gas chromatography-mass spectrometry (GC-MS). The effects of identity of extraction solvent, extraction temperature, sample agitation, extraction time, and salt concentration on extraction performance were also investigated. Good enrichments were achieved (65-211-fold) with this method. Good repeatabilities of extraction were obtained, with RSD values below 15.2%. Detection limits were 0.209 microg/l or lower. PMID:18001752

  4. Measurement and simulation of two-phase CO2 cooling in Micromegas modules for a Large Prototype of Time Projection Chamber

    NASA Astrophysics Data System (ADS)

    Bhattacharya, D. S.; Attié, D.; Colas, P.; Mukhopadhyay, S.; Majumdar, N.; Bhattacharya, S.; Sarkar, S.; Bhattacharya, A.; Ganjour, S.

    2015-08-01

    The readout electronics of a Micromegas (MM) module consume nearly 26 W of electric power, which causes the temperature of electronic board to increase upto 70 oC. Increase in temperature results in damage of electronics. Development of temperature gradient in the Time Projection Chamber (TPC) may affect precise measurement as well. Two-phase CO2 cooling has been applied to remove heat from the MM modules during two test beam experiments at DESY, Hamburg. Following the experimental procedure, a comprehensive study of the cooling technique has been accomplished for a single MM module by means of numerical simulation. This paper is focused to discuss the application of two-phase CO2 cooling to keep the temperature below 30 oC and stabilized within 0.2 oC.

  5. The influence of cooling conditions on grain size, secondary phase precipitates and mechanical properties of biomedical alloy specimens produced by investment casting.

    PubMed

    Kaiser, R; Williamson, K; O'Brien, C; Ramirez-Garcia, S; Browne, D J

    2013-08-01

    The objective of this work was to investigate and evaluate the effect of the cooling environment on the microstructure, secondary phase precipitates and mechanical properties of an as-cast cobalt alloy. The microstructure of castings has a large bearing on the mechanical properties, grain size, porosity and the morphology of carbide precipitates are thought to influence hardness, tensile strength and ductility. It is postulated that a greater understanding of microstructure and secondary phase precipitate response to casting parameters could lead to the optimisation of casting parameters and serve to reduce the requirement of thermo-mechanical treatments currently applied to refine as-cast structures and achieve adequate mechanical properties. Thermal analysis was performed to determine the critical stages of cooling. Ten millimetre diameter cylindrical specimens which could be machined into tension test specimens were cast and cooled under different conditions to impose different cooling rates. Analytical techniques such as optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDX), tensile testing and micro-hardness testing were used to study the specimens. Parameters studied include grain size, secondary dendrite arm spacing, secondary phase precipitates, porosity, hardness, ultimate tensile strength, yield strength and elongation. The microstructure of as-cast Co-28Cr-6Mo was found to consist of a dendritic matrix with secondary phases precipitated at grain boundaries and interdendritic zones. These secondary phase precipitates consist of carbides, rich in chromium and molybdenum. The size and area fraction of carbides was found to decrease significantly with increasing cooling rate while the micro-porosity was only marginally affected. The as-cast grains are illustrated for the first time showing a significant difference in size between insulated and naturally cooled specimens. The secondary dendrite arm spacing was determined to be significantly affected by the various cooling environments and the mechanical properties of hardness, ultimate tensile strength and yield strength all increased with increasing cooling rate while the ductility decreased. Correlations between microstructural features and mechanical properties are proposed. PMID:23683759

  6. Alaska Regional Energy Resources Planning Project. Phase 2: coal, hydroelectric and energy alternatives. Volume I. Beluga Coal District Analysis

    SciTech Connect

    Rutledge, G.; Lane, D.; Edblom, G.

    1980-01-01

    This volume deals with the problems and procedures inherent in the development of the Beluga Coal District. Socio-economic implications of the development and management alternatives are discussed. A review of permits and approvals necessary for the initial development of Beluga Coal Field is presented. Major land tenure issues in the Beluga Coal District as well as existing transportation routes and proposed routes and sites are discussed. The various coal technologies which might be employed at Beluga are described. Transportation options and associated costs of transporting coal from the mine site area to a connecting point with a major, longer distance transportation made and of transporting coal both within and outside (exportation) the state are discussed. Some environmental issues involved in the development of the Beluga Coal Field are presented. (DMC)

  7. Cooling causes changes in the distribution of lipoprotein lipase and milk fat globule membrane proteins between the skim milk and cream phase.

    PubMed

    Dickow, J A; Larsen, L B; Hammershøj, M; Wiking, L

    2011-02-01

    Lipoprotein lipase (LPL) activity and free fatty acid levels were studied in freshly milked, uncooled milk from individual Danish Holstein or Jersey cows, or after storage for up to 24h at either a cooling temperature (4°C) or at the milking temperature (31°C). Upon cooling for up to 24h, LPL activity increased in the cream phase, whereas the activity in the skim milk was steady, as observed for Jersey cows, or increased, as seen for the Holsteins. Storage at 31°C decreased the LPL activity in both the cream phase and the skim milk phase. The increase in free fatty acid levels was found to depend on LPL activity, incubation temperature, substrate availability, and incubation time. Furthermore, the migration of milk proteins between the skim milk phase and the cream phase upon cooling of milk from Jersey cows or from Danish Holstein cows was studied using proteomic methods involving 2-dimensional gel electrophoresis and mass spectrometry. Proteins associated with the milk fat globules were isolated from all milk fractions and analyzed. Major changes in the distributions of proteins between the skim milk phase and the cream phase were observed after cooling at 4°C for 4h, where a total of 29 proteins between the 2 breeds was found to change their association with the milk fat globule membrane (MFGM) significantly. Among these, the MFGM proteins adipophilin, fatty acid-binding protein, and lactadherin, as well as the non-MFGM proteins β-casein, lactoferrin, and heat shock protein-71, were identified. Adipophilin, lactadherin, and lactoferrin were quantitatively more associated with the MFGM upon cold storage at 4°C, whereas β-casein, fatty acid-binding protein, and heat shock protein-71 were found to be less associated with the MFGM upon cold storage. PMID:21257033

  8. Studies of Phase Change Materials and a Latent Heat Storage Unit Used for a Natural Circulation Cooling/Latent Heat Storage System

    NASA Astrophysics Data System (ADS)

    Sakitani, Katsumi; Honda, Hiroshi

    Experimental and theoretical studies were made of the heat transfer characteristics of a latent heat storage unit used for a natural circulation cooling /latent heat storage system. Heating and cooling curves of the latent heat storage unit undergoing solid-liquid phase change of a PCM (lauric acid) was obtained by using anatural circulation loop of R22 which consisted of an electrically heated evaporater, a water cooled condenser and the latent heat storage unit. The latent heat storage unit showed a heat transfer performance which was high enough for practical use. An approximate theoretical analysis was conducted to investigate transient behavior of the latent heat storage unit. Predictions of the refrigerant and outer surface temperatures during the melting process were in fair agreement with the experimental data, whereas that of the refrigerant temperature during the solidification process was considerably lower than the measurement.

  9. Stochastic cooling

    SciTech Connect

    Bisognano, J.; Leemann, C.

    1982-03-01

    Stochastic cooling is the damping of betatron oscillations and momentum spread of a particle beam by a feedback system. In its simplest form, a pickup electrode detects the transverse positions or momenta of particles in a storage ring, and the signal produced is amplified and applied downstream to a kicker. The time delay of the cable and electronics is designed to match the transit time of particles along the arc of the storage ring between the pickup and kicker so that an individual particle receives the amplified version of the signal it produced at the pick-up. If there were only a single particle in the ring, it is obvious that betatron oscillations and momentum offset could be damped. However, in addition to its own signal, a particle receives signals from other beam particles. In the limit of an infinite number of particles, no damping could be achieved; we have Liouville's theorem with constant density of the phase space fluid. For a finite, albeit large number of particles, there remains a residue of the single particle damping which is of practical use in accumulating low phase space density beams of particles such as antiprotons. It was the realization of this fact that led to the invention of stochastic cooling by S. van der Meer in 1968. Since its conception, stochastic cooling has been the subject of much theoretical and experimental work. The earliest experiments were performed at the ISR in 1974, with the subsequent ICE studies firmly establishing the stochastic cooling technique. This work directly led to the design and construction of the Antiproton Accumulator at CERN and the beginnings of p anti p colliding beam physics at the SPS. Experiments in stochastic cooling have been performed at Fermilab in collaboration with LBL, and a design is currently under development for a anti p accumulator for the Tevatron.

  10. Monoclinic MB phase and phase instability in [110] field cooled Pb(Zn1/3Nb2/3)O3-4.5%PbTiO3 single crystals

    NASA Astrophysics Data System (ADS)

    Yao, Jianjun; Cao, Hu; Ge, Wenwei; Li, Jiefang; Viehland, D.

    2009-08-01

    We report the finding of a monoclinic MB phase in Pb(Zn1/3Nb2/3)O3-4.5%PbTiO3 single crystals. High precision x-ray diffraction investigations of [110] field cooled crystals have shown a transformation sequence of cubic(C)→tetragonal(T)→orthorhombic(O)→monoclinic(MB), which is different from that previously reported [A.-E. Renault et al., J. Appl. Phys. 97, 044105 (2005)]. Beginning in the zero-field-cooled condition at 383 K, a rhombohedral (R)→MB→O sequence was observed with increasing field. Coexisting MB and O phases were then found upon removal of field, which fully transformed to MB on cooling to room temperature.

  11. Co-sponsored second quarter progress review conference on district heating

    SciTech Connect

    1980-01-01

    A summary of the progress review conference on district heating and cooling systems is presented. The agenda and lists of speakers and attendees are presented. A history of district heating and some present needs and future policies are given and an excerpt from the National District Heating Program Strategy (DOE, March 1980) is included. Following the presentation, District Heating and Cooling Systems Program, by Alan M. Rubin, a fact sheet on DOE's Integrated Community Energy Systems Program and information from an oral presentation, District Heating and Cooling Systems for Communities Through Power Plant Retrofit Distribution Network, are given. The Second Quarterly Oral Report to the US DOE on the District Heating and Cooling Project in Detroit; the executive summary of the Piqua, Ohio District Heating and Cooling Demonstration Project; the Second Quarterly Report of the Moorehead, Minnesota District Heating Project; and the report from the Moorehead, Minnesota mayor on the Hot Water District Heating Project are presented.

  12. Development of Continuous Cooling Transformation Diagrams of Zirconium-Niobium Alloy Phase Transformations within the Kolmogorov-Johnson-Mehl-Avrami Framework

    NASA Astrophysics Data System (ADS)

    Kautz, Elizabeth J.

    Microstructure and chemistry of zirconium alloys have a major influence on material performance, including mechanical properties and corrosion resistance. Therefore, it is essential to thoroughly understand processing required to obtain desired microstructures for application in commercial nuclear reactors. Zirconium-niobium alloys are of particular interest for commercial nuclear applications (e.g., in boiling water reactors, pressurized water reactors, Canadian deuterium uranium reactors) due to increased corrosion resistance in aqueous environments over other zirconium alloys. Heat treatments of zirconium-niobium alloys affect overall microstructure, precipitate distributions and size, and ultimately determine material performance. Phase transformations in zirconium-niobium alloys were modeled for a range of niobium concentrations and heat treatment conditions, by conducting controlled experiments. Heat-flux differential scanning calorimetry was performed and data was collected and analyzed for zirconium-niobium alloys with niobium content ranging from 0.6-3.0 weight percent. Continuous cooling transformation diagrams were constructed for slow cooling rate conditions (9-34°C/minute) based on calorimetry test results. A standard operating procedure for performing these calorimetry tests and corresponding data analysis technique was developed specifically to study the zirconium-niobium material system. A mathematical model was developed utilizing the Kolmogorov-Johnson-Mehl-Avrami theory that accurately describes phase transformations upon continuous cooling in zirconium-niobium binary alloys. This model relates fraction of phase transformed to kinetic parameters that were calculated from experimental test results in order to model the phase transformation for various cooling rates from 10-40°C/minute.

  13. Two-phase zone at Al2O3 meltin by laser radiation and at melt solidification under the conditions of free cooling

    NASA Astrophysics Data System (ADS)

    Bityukov, V. K.; Petrov, V. A.; Smirnov, I. V.

    2009-09-01

    Experiments and numerical simulation have shown that the two-phase zone of liquid and solid phases concentration, variable over the coordinate, is formed both at alumina heating by laser radiation and at free melt cooling. During heating this zone is formed only at the initial stage of heating. Its width is not large and is lesser than the depth of the heating laser beam penetration due to the effect of intense heat losses through the crystal by thermal radiation and thermal conductivity. Extension of the two-phase zone formed at crystallization is much more under the conditions of free cooling than at melting, and it can cover almost the whole thickness of the melt. Temperature plateau of the brightness (effective) temperature registered at solidification by the pyrometer with the wavelength of 0.65 µm is explained by formation of the extensive two-phase zone. However, this plateau is realized not for all wavelengths. The importance of the melt absorption coefficient influence on probable appearance of temperature plateau is shown. As a result of crystallization with the two-phase zone formation, porous structure consisting of the crystals with small size can be formed. It may cause the diffuse surface reflectivity.

  14. Thermohydraulics in a high-temperature gas-cooled reactor primary loop during early phases of unrestricted core-heatup accidents

    SciTech Connect

    Kroeger, P.G.; Colman, J.; Hsu, C.J.

    1983-01-01

    In High Temperature Gas Cooled Reactor (HTGR) siting considerations, the Unrestricted Core Heatup Accidents (UCHA) are considered as accidents of highest consequence, corresponding to core meltdown accidents in light water reactors. Initiation of such accidents can be, for instance, due to station blackout, resulting in scram and loss of all main loop forced circulation, with none of the core auxiliary cooling system loops being started. The result is a slow but continuing core heatup, extending over days. During the initial phases of such UCHA scenarios, the primary loop remains pressurized, with the system pressure slowly increasing until the relief valve setpoint is reached. The major objectives of the work described here were to determine times to depressurization as well as approximate loop component temperatures up to depressurization.

  15. Phase 1 archaeological investigation, cultural resources survey, Hawaii Geothermal Project, Makawao and Hana districts, south shore of Maui, Hawaii

    SciTech Connect

    Erkelens, C.

    1995-04-01

    This report details the archaeological investigation of a 200 foot wide sample corridor extending approximately 9 miles along the southern portion of Maui within the present districts of Hana and Makawao. The survey team documented a total of 51 archaeological sites encompassing 233 surface features. Archaeological sites are abundant throughout the region and only become scarce where vegetation has been bulldozed for ranching activities. At the sea-land transition points for the underwater transmission cable, both Ahihi Bay and Huakini Bay are subjected to seasonal erosion and redeposition of their boulder shorelines. The corridor at the Ahihi Bay transition point runs through the Maonakala Village Complex which is an archaeological site on the State Register of Historic Places within a State Natural Area Reserve. Numerous other potentially significant archaeological sites lie within the project corridor. It is likely that rerouting of the corridor in an attempt to avoid known sites would result in other undocumented sites located outside the sample corridor being impacted. Given the distribution of archaeological sites, there is no alternative route that can be suggested that is likely to avoid encountering sites. Twelve charcoal samples were obtained for potential taxon identification and radiocarbon analysis. Four of these samples were subsequently submitted for dating and species identification. Bird bones from various locations within a lava tube were collected for identification. Sediment samples for subsequent pollen analysis were obtained from within two lava tubes. With these three sources of information it is hoped that paleoenvironmental data can be recovered that will enable a better understanding of the setting for Hawaiian habitation of the area.

  16. Phase I Archaeological Investigation Cultural Resources Survey, Hawaii Geothermal Project, Makawao and Hana Districts, South Shore of Maui, Hawaii (DRAFT )

    SciTech Connect

    Erkelens, Conrad

    1994-03-01

    This report details the archaeological investigation of a 200 foot wide sample corridor extending approximately 9 miles along the southern portion of Maui within the present districts of Hana and Makawao. A total of 51 archaeological sites encompassing 233 surface features were documented. A GPS receiver was used to accurately and precisely plot locations for each of the documented sites. Analysis of the locational information suggests that archaeological sites are abundant throughout the region and only become scarce where vegetation has been bulldozed for ranching activities. At the sea-land transition points for the underwater transmission cable, both Ahihi Bay and Huakini Bay are subjected to seasonal erosion and redeposition of their boulder shorelines. The corridor at the Ahihi Bay transition point runs through the Moanakala Village Complex which is an archaeological site on the State Register of Historic Places within a State Natural Area Reserve. Numerous other potentially significant archaeological sites lie within the project corridor. It is likely that rerouting of the corridor in an attempt to avoid known sites would result in other undocumented sites located outside the sample corridor being impacted. Given the distribution of archaeological sites, there is no alternative route that can be suggested that is likely to avoid encountering sites. A total of twelve charcoal samples were obtained for potential taxon identification and radiocarbon analysis. Four of these samples were subsequently submitted for dating and species identification. Bird bone from various locations within a lava tube were collected for identification. Sediment samples for subsequent pollen analysis were obtained from within two lava tubes. With these three sources of information it is hoped that paleoenvironmental data can be recovered that will enable a better understanding of the setting for Hawaiian habitation of the area. A small test unit was excavated at one habitation site. Charcoal, molluscan and fish remains, basalt tools, and other artifacts were recovered. This material, while providing an extremely small sample, will greatly enhance our understanding of the use of the area. Recommendations regarding the need for further investigation and the preservation of sites within the project corridor are suggested. All sites within the project corridor must be considered potentially significant at this juncture. Further archaeological investigation consisting of a full inventory survey will be required prior to a final assessment of significance for each site and the development of a mitigation plan for sites likely to be impacted by the Hawaii Geothermal Project.

  17. Cooling concept integration. Phase I final technical report, October 1, 1979-July 31, 1981. [For pre-engineered metal buildings

    SciTech Connect

    Fraker, H.; Glennie, W.; Snyder, M.K.

    1981-08-19

    Before specific test prototypes were developed, six potential evaporative roof cooling configurations with alternative storage and heat transfer mechanisms were examined, and preliminary cost estimates were made. Each system uses a wet roof system which sprays or floods the roof, allowing evaporative heat transfer to the environment. Finite difference thermal network methods were used for the evaluation of the systems. Detailed results including charts of the hourly heat flows during particular days are presented, and the performance is summarized for Las Vegas. (LEW)

  18. Method and apparatus maintaining multi-component sample gas constituents in vapor phase during sample extraction and cooling

    DOEpatents

    Farthing, William Earl; Felix, Larry Gordon; Snyder, Todd Robert

    2009-12-15

    An apparatus and method for diluting and cooling that is extracted from high temperature and/or high pressure industrial processes. Through a feedback process, a specialized, CFD-modeled dilution cooler is employed along with real-time estimations of the point at which condensation will occur within the dilution cooler to define a level of dilution and diluted gas temperature that results in a gas that can be conveyed to standard gas analyzers that contains no condensed hydrocarbon compounds or condensed moisture.

  19. Method and apparatus for maintaining multi-component sample gas constituents in vapor phase during sample extraction and cooling

    DOEpatents

    Farthing, William Earl [Pinson, AL; Felix, Larry Gordon [Pelham, AL; Snyder, Todd Robert [Birmingham, AL

    2008-02-12

    An apparatus and method for diluting and cooling that is extracted from high temperature and/or high pressure industrial processes. Through a feedback process, a specialized, CFD-modeled dilution cooler is employed along with real-time estimations of the point at which condensation will occur within the dilution cooler to define a level of dilution and diluted gas temperature that results in a gas that can be conveyed to standard gas analyzers that contains no condensed hydrocarbon compounds or condensed moisture.

  20. Stochastic Cooling

    SciTech Connect

    Blaskiewicz, M.

    2011-01-01

    Stochastic Cooling was invented by Simon van der Meer and was demonstrated at the CERN ISR and ICE (Initial Cooling Experiment). Operational systems were developed at Fermilab and CERN. A complete theory of cooling of unbunched beams was developed, and was applied at CERN and Fermilab. Several new and existing rings employ coasting beam cooling. Bunched beam cooling was demonstrated in ICE and has been observed in several rings designed for coasting beam cooling. High energy bunched beams have proven more difficult. Signal suppression was achieved in the Tevatron, though operational cooling was not pursued at Fermilab. Longitudinal cooling was achieved in the RHIC collider. More recently a vertical cooling system in RHIC cooled both transverse dimensions via betatron coupling.

  1. Two-stage magneto-optical trapping and narrow-line cooling of Li6 atoms to high phase-space density

    NASA Astrophysics Data System (ADS)

    Sebastian, J.; Gross, Ch.; Li, Ke; Gan, H. C. J.; Li, Wenhui; Dieckmann, K.

    2014-09-01

    We report an experimental study of peak and phase-space density of a two-stage magneto-optical trap (MOT) of Li6 atoms, which exploits the narrower 2S1/2→3P3/2 ultraviolet (UV) transition at 323 nm following trapping and cooling on the more common D2 transition at 671 nm. The UV MOT is loaded from a red MOT and is compressed to give a high phase-space density up to 3×10-4. Temperatures as low as 33μK are achieved on the UV transition. We study the density limiting factors and in particular find a value for the light-assisted collisional loss coefficient of 1.3±0.4×10-10 cm3/s for low repumping intensity.

  2. Silico-ferrite of Calcium and Aluminum (SFCA) Iron Ore Sinter Bonding Phases: New Insights into Their Formation During Heating and Cooling

    NASA Astrophysics Data System (ADS)

    Webster, Nathan A. S.; Pownceby, Mark I.; Madsen, Ian C.; Kimpton, Justin A.

    2012-12-01

    The formation of silico-ferrite of calcium and aluminum (SFCA) and SFCA-I iron ore sinter phases during heating and cooling of synthetic iron ore sinter mixtures in the range 298 K to 1623 K (25 °C to 1350 °C) and at oxygen partial pressure of 5 × 10-3 atm has been characterized using in situ synchrotron X-ray diffraction. SFCA and SFCA-I are the key bonding phases in iron ore sinter, and an improved understanding of their formation mechanisms may lead to improved efficiency of industrial sintering processes. During heating, SFCA-I formation at 1327 K to 1392 K (1054 °C to 1119 °C) (depending on composition) was associated with the reaction of Fe2O3, 2CaO·Fe2O3, and SiO2. SFCA formation (1380 K to 1437 K [1107 °C to 1164 °C]) was associated with the reaction of CaO·Fe2O3, SiO2, and a phase with average composition 49.60, 9.09, 0.14, 7.93, and 32.15 wt pct Fe, Ca, Si, Al, and O, respectively. Increasing Al2O3 concentration in the starting sinter mixture increased the temperature range over which SFCA-I was stable before the formation of SFCA, and it stabilized SFCA to a higher temperature before it melted to form a Fe3O4 + melt phase assemblage (1486 K to 1581 K [1213 °C to 1308 °C]). During cooling, the first phase to crystallize from the melt (1452 K to 1561 K [1179 °C to 1288 °C]) was an Fe-rich phase, similar in composition to SFCA-I, and it had an average composition 58.88, 6.89, 0.82, 3.00, and 31.68 wt pct Fe, Ca, Si, Al, and O, respectively. At lower temperatures (1418 K to 1543 K [1145 °C to 1270 °C]), this phase reacted with melt to form SFCA. Increasing Al2O3 increased the temperature at which crystallization of the Fe-rich phase occurred, increased the temperature at which crystallization of SFCA occurred, and suppressed the formation of Fe2O3 (1358 K to 1418 K [1085 °C to 1145 °C]) to lower temperatures.

  3. High-Resolution Measurements of Electron Temperature, Density, and Width Profiles of 234 Coronal Loops in the Non-Equilibrium Cooling Phase

    NASA Astrophysics Data System (ADS)

    Nightingale, R. W.; Aschwanden, M. J.

    2008-05-01

    We measure the profiles of the electron temperature Te(s), the electron density ne(s), and loop widths w(s) of 234 coronal loops from triple-filter TRACE data. We model also the loop geometry with a semi-circular model in order to measure the unprojected full loop length L and the inclination angle θ of the loop plane to the vertical, which are both required to apply loop scaling laws and hydrodynamic models. The statistics of the measured loop parameters are: electron temperatures Te=1.18±0.30 MK, electron densities ne=10(9.0± 0.2) cm-3, loop widths w=1.44±0.33 Mm, loop lengths L=56± 47 Mm, fraction of detected loop lengths Ldet/L =0.67±0.23, and loop inclination angles |θ|=22° ± 18°. From these parameters we determine the average overpressure of these loops with respect to the equilibrium RTV law, q=p/pRTV and find that 86% of the loops exhibit an overpressure (up to q < 30), 9% an underpressure, and only about 5% are consistent with RTV. We interpret the observed overpressure as a natural consequence of the non-equilibrium cooling phase. Applying a non-equilibrium scaling law we predict that the loops were heated to soft X-ray temperatures up to Te < 15 MK prior to their cooling to EUV wavelengths. For the loop lifetimes we find an approximate scaling of τlife ≍ 10 (L/10 Mm)2 min, with a median lifetime of 7 hours for our sample of TRACE loops. This study postulates a paradigm shift from equilibrium models to non-equilibrium models in the loop cooling phase, which is dominantly observed in EUV wavelengths. This work was supported in part by NASA under the TRACE contract NAS5-38099.

  4. District heating and cooling systems for communities through power plant retrofit distribution network. Phase 2. Final report, 1 March 1980-31 January 1984. Volume VII. Appendix C

    SciTech Connect

    Not Available

    1984-01-31

    This volume contains: Hudson No. 2 Limited Retrofit Cost Estimates provided by Stone and Webster Engineering Corp. (SWEC); backup data and basis of estimate for SWEC Heater Plant and Gas Turbine Plant (Kearny No. 12) cost estimates; and Appendices - Analysis of Relevant Tax Laws.

  5. Microseismic monitoring for evidence of geothermal heat in the capital district of New York. Final report, Phases I-III

    SciTech Connect

    Not Available

    1983-06-01

    The seismic monitoring work of the geothermal project was initiated for the purpose of determining more exactly the relationship between seismicity and the postulated geothermal and related activity in the Albany-Saratoga Springs area in upstate New York. The seismic monitoring aspect of this work consisted of setting up and operating a network of seven seismograph stations within and around the study area capable of detecting and locating small earthquakes. To supplement the evidence from present day seismic activity, a list of all known historical and early instrumental earthquakes was compiled and improved from original sources for a larger region centered on the study area. Additional field work was done to determine seismic velocities of P and S phases by special recording of quarry blasts. The velocity results were used both as an aid to improve earthquake locations based on computer programs and to make inferences about the existence of temperature anomalies, and hence geothermal potential, at depths beneath the study area. Finally, the level in the continuous background earth vibration, microseisms, was measured throughout the study area to test a possibility that a relationship may exist at the surface between the level in microseisms and the geothermal or related activity. The observed seismic activity within the study area, although considerably higher (two to three times) than inferred from the historical and early instrumental data, is still not only low for a potential geothermal area but appears to be related to coherent regional tectonic stresses and not to the proposed more localized geothermal activity reflected in the mineralized, CO/sub 2/ rich spring discharge.

  6. A NEUTRON STAR STIFF EQUATION OF STATE DERIVED FROM COOLING PHASES OF THE X-RAY BURSTER 4U 1724-307

    SciTech Connect

    Suleimanov, Valery; Werner, Klaus; Poutanen, Juri; Revnivtsev, Mikhail E-mail: werner@astro.uni-tuebingen.de

    2011-12-01

    Thermal emission during X-ray bursts is a powerful tool for determining neutron star (NS) masses and radii if the Eddington flux and the apparent radius in the cooling tail can be measured accurately and distances to the sources are known. We propose here an improved method of determining the basic stellar parameters using the data from the cooling phase of photospheric radius expansion (PRE) bursts covering a large range of luminosities. Because at that phase the blackbody apparent radius depends only on the spectral hardening factor (color correction), we suggest fitting the theoretical dependences of the color correction versus flux in Eddington units to the observed variations of the inverse square root of the apparent blackbody radius with the flux. For that we use a large set of atmosphere models for burst luminosities varying by three orders of magnitude and for various chemical compositions and surface gravities. We show that spectral variations observed during a long PRE burst from 4U 1724-307 are entirely consistent with the theoretical expectations for the passively cooling NS atmospheres. Our method allows us to more reliably determine both the Eddington flux (which is found to be smaller than the touchdown flux by 15%) and the ratio of the stellar apparent radius to the distance. We then find a lower limit on the NS radius of 14 km for masses below 2.3 M{sub Sun }, independently of the chemical composition. These results suggest that the matter inside NSs is characterized by a stiff equation of state. We also find evidence in favor of hydrogen-rich accreting matter and obtain an upper limit to the distance of 7 kpc. We finally show that the apparent blackbody emitting area in the cooling tails of the short bursts from 4U 1724-307 is two times smaller than that for the long burst and their evolution does not follow the theory. This makes their usage for determining the NS parameters questionable and casts serious doubt on the results of previous works that used similar bursts from other sources for analysis.

  7. District heating strategy model: community manual

    SciTech Connect

    Hrabak, R. A.; Kron, Jr., N. F.; Pferdehirt, W. P.

    1981-10-01

    The US Department of Housing and Urban Development (HUD) and the US Department of Energy (DOE) cosponsor a program aimed at increasing the number of district heating and cooling systems. Twenty-eight communities have received HUD cooperative agreements to aid in a national feasibility assessment of district heating and cooling systems. The HUD/DOE program includes technical assistance provided by Argonne National Laboratory and Oak Ridge National Laboratory. Part of this assistance is a computer program, called the district heating strategy model, that performs preliminary calculations to analyze potential district heating and cooling systems. The model uses information about a community's physical characteristics, current electricity-supply systems, and local economic conditions to calculate heat demands, heat supplies from existing power plants and a new boiler, system construction costs, basic financial forecasts, and changes in air-pollutant emissions resulting from installation of a district heating and cooling system. This report explains the operation of the district heating strategy model, provides simplified forms for organizing the input data required, and describes and illustrates the model's output data. The report is written for three groups of people: (1) those in the HUD/DOE-sponsored communities who will be collecting input data, and studying output data, to assess the potential for district heating and cooling applications in their communiites; (2) those in any other communities who may wish to use the model for the same purpose; and (3) technical-support people assigned by the national laboratories to explain to community personnel how the model is used.

  8. New petrological constraints on the last eruptive phase of the Sabatini Volcanic District (central Italy): Clues from mineralogy, geochemistry, and Sr-Nd isotopes

    NASA Astrophysics Data System (ADS)

    Del Bello, Elisabetta; Mollo, Silvio; Scarlato, Piergiorgio; von Quadt, Albrecht; Forni, Francesca; Bachmann, Olivier

    2014-09-01

    We report results from mineralogical, geochemical and isotopic analyses of the three youngest pyroclastic products (ca. 86 ky) belonging to the Sabatini Volcanic District (Roman Province, central Italy). By means of thermometers, hygrometers and oxygen barometers, we have estimated that the crystallization temperature of magma progressively decreases over time (910-740 °C), whereas the amount of water dissolved in the melt and fO2 progressively increases as compositions of magmas become more differentiated (4.5-6.4 wt.% H2O and 0.4-2.6 ΔQFM buffer, respectively). Thermodynamic simulations of phase equilibria indicate that geochemical trends in mafic magmas (MgO > 4 wt.%) can be reproduced by abundant fractionation of olivine and clinopyroxene (~ 50 wt.% crystallization), while the trends of more evolved magmas (MgO ≤ 4 wt.%) originated by fractional crystallization of plagioclase and sanidine (~ 45 wt.% crystallization). The behavior of trace elements highlights that magmatic differentiation is controlled by polybaric differentiation that includes: (1) prolonged fractionation of mafic, anhydrous minerals from a primitive, H2O-poor magma at depth and (2) extraction of a more evolved, H2O-rich magma that crystallizes abundant felsic and subordinated hydrous minerals at shallow crustal levels. Assimilation and fractional crystallization modeling also reveal that magmas interacted with the carbonate rocks of the subvolcanic basement. The effect of carbonate assimilation accounts for both trace element and Sr-Nd isotopic variations in magmas, suggesting a maximum degree of carbonate assimilation of less than 5 wt.%.

  9. Benchmarking of thermal hydraulic loop models for Lead-Alloy Cooled Advanced Nuclear Energy System (LACANES), phase-I: Isothermal steady state forced convection

    NASA Astrophysics Data System (ADS)

    Cho, Jae Hyun; Batta, A.; Casamassima, V.; Cheng, X.; Choi, Yong Joon; Hwang, Il Soon; Lim, Jun; Meloni, P.; Nitti, F. S.; Dedul, V.; Kuznetsov, V.; Komlev, O.; Jaeger, W.; Sedov, A.; Kim, Ji Hak; Puspitarini, D.

    2011-08-01

    As highly promising coolant for new generation nuclear reactors, liquid Lead-Bismuth Eutectic has been extensively worldwide investigated. With high expectation about this advanced coolant, a multi-national systematic study on LBE was proposed in 2007, which covers benchmarking of thermal hydraulic prediction models for Lead-Alloy Cooled Advanced Nuclear Energy System (LACANES). This international collaboration has been organized by OECD/NEA, and nine organizations - ENEA, ERSE, GIDROPRESS, IAEA, IPPE, KIT/IKET, KIT/INR, NUTRECK, and RRC KI - contribute their efforts to LACANES benchmarking. To produce experimental data for LACANES benchmarking, thermal-hydraulic tests were conducted by using a 12-m tall LBE integral test facility, named as Heavy Eutectic liquid metal loop for integral test of Operability and Safety of PEACER (HELIOS) which has been constructed in 2005 at the Seoul National University in the Republic of Korea. LACANES benchmark campaigns consist of a forced convection (phase-I) and a natural circulation (phase-II). In the forced convection case, the predictions of pressure losses based on handbook correlations and that obtained by Computational Fluid Dynamics code simulation were compared with the measured data for various components of the HELIOS test facility. Based on comparative analyses of the predictions and the measured data, recommendations for the prediction methods of a pressure loss in LACANES were obtained. In this paper, results for the forced convection case (phase-I) of LACANES benchmarking are described.

  10. IR and UV spectroscopy of vapor-phase jet-cooled ionic liquid [emim]+ [Tf2N]-: ion pair structure and photodissociation dynamics.

    PubMed

    Cooper, Russell; Zolot, Alexander M; Boatz, Jerry A; Sporleder, David P; Stearns, Jaime A

    2013-11-27

    Small gas-phase clusters (ion pairs) of the ionic liquid [emim](+)[Tf2N](-) have been generated in a supersonic expansion. Clusters are investigated via UV photofragmentation and time-of-flight mass spectrometry. Spectra between 42,000 and 45,000 cm(-1) reveal dynamical branching between direct dissociation of the ion pair to the cation and anion and to radical species. The IR spectrum between 2800 and 3200 cm(-1) was measured by action spectroscopy. Multiple conformations of the ion pair are found to be present in the molecular beam, leading to broad spectral features, further complicated by hydrogen bonding and Fermi resonances. The measured and theoretical spectra compare well, and the jet-cooled ion pair structures present in the molecular beam are strongly hydrogen bonded "stacked" conformers. PMID:24175625

  11. Optimization of evaporative cooling

    NASA Astrophysics Data System (ADS)

    Sackett, C. A.; Bradley, C. C.; Hulet, R. G.

    1997-05-01

    Recent experiments have used forced evaporative cooling to produce Bose-Einstein condensation in dilute gases. The evaporative cooling process can be optimized to provide the maximum phase-space density with a specified number of atoms remaining. We show that this global optimization is approximately achieved by locally optimizing the cooling efficiency at each instant. We discuss how this method can be implemented, and present the results for our 7Li trap. The predicted behavior of the gas is found to agree well with experiment.

  12. Muon cooling channels

    SciTech Connect

    Eberhard K Keil

    2003-03-10

    A procedure uses the equations that govern ionization cooling, and leads to the most important parameters of a muon cooling channel that achieves assumed performance parameters. First, purely transverse cooling is considered, followed by both transverse and longitudinal cooling in quadrupole and solenoid channels. Similarities and differences in the results are discussed in detail, and a common notation is developed. Procedure and notation are applied to a few published cooling channels. The parameters of the cooling channels are derived step by step, starting from assumed values of the initial, final and equilibrium emittances, both transverse and longitudinal, the length of the cooling channel, and the material properties of the absorber. The results obtained include cooling lengths and partition numbers, amplitude functions and limits on the dispersion at the absorber, length, aperture and spacing of the absorber, parameters of the RF system that achieve the longitudinal amplitude function and bucket area needed. Finally, I compute the merit factor that describes the enhancement of the density in 6D phase space. The consequences of changes in the input parameters are discussed. The lattice parameters needed to achieve the assumed performance are summarized. The design proper of such a lattice, i.e. finding the precise arrangement of magnets, RF cavities, absorbers, etc., which has these properties is well beyond the scope of this document.

  13. Direct visualization and measurement of the extrapolation length on cooling toward the nematic-smectic-A phase transition temperature.

    PubMed

    Choi, Yoonseuk; Rosenblatt, Charles

    2010-05-01

    A herringbone "easy axis" pattern is scribed into a polyimide alignment layer for liquid-crystal orientation using the stylus of an atomic force microscope. Owing to the liquid crystal's bend elasticity K33 , the nematic director is unable to follow the sharp turn in the scribed easy axis, but instead relaxes over an extrapolation length L=K33/W2φ, where W2φ is the quadratic azimuthal anchoring strength coefficient. By immersing a tapered optical fiber into the liquid crystal, illuminating the fiber with polarized light, and scanning the fiber close to the substrate, a visualization and direct measurement of L are obtained on approaching the nematic-smectic- A phase transition temperature T NA from above. L is found to exhibit a sharp pretransitional increase near T NA, consistent with a diverging bend elastic constant. PMID:20866248

  14. Cooling the two-dimensional short spherocylinder liquid to the tetratic phase: Heterogeneous dynamics with one-way coupling between rotational and translational hopping.

    PubMed

    Su, Yen-Shuo; I, Lin

    2015-07-01

    We numerically demonstrate the transition from the isotropic liquid to the tetratic phase with quasilong-range tetratic alignment order (i.e., with nearly parallel or perpendicular aligned rods), for the cold two-dimensional (2D) short spherocylinder system before crystallization and investigate the thermal assisted heterogeneous rotational and translational micromotions. Comparing with the 2D liquid of isotropic particles, spherocylinders introduce extra rotational degrees of freedom and destroy packing isotropy and the equivalence between rotational and translational motions. It is found that cooling leads to the stronger dynamical heterogeneity with more cooperative hopping and the stronger retardations of rotational hopping than translational hopping. Under topological constraints from nearly parallel and perpendicular rods of the tetratic phase, longitudinal and transverse translational hopping can occur without rotational hopping, but not the reverse. The empty space trailing a neighboring translational hopping patch is needed for triggering the patch rotational hopping with its translational motion into the empty space. It is the origin for the observed increasing separation of hopping time scales and the one-way coupling between rotational and translational hopping. Strips of longitudinally or transversely aligned rods can be ruptured and reconnected with neighboring strips through buckling, kink formation, and patch rotation, under the unbalanced torques or forces from their neighboring rods and thermal kicks. PMID:26274173

  15. Cooling the two-dimensional short spherocylinder liquid to the tetratic phase: Heterogeneous dynamics with one-way coupling between rotational and translational hopping

    NASA Astrophysics Data System (ADS)

    Su, Yen-Shuo; I, Lin

    2015-07-01

    We numerically demonstrate the transition from the isotropic liquid to the tetratic phase with quasilong-range tetratic alignment order (i.e., with nearly parallel or perpendicular aligned rods), for the cold two-dimensional (2D) short spherocylinder system before crystallization and investigate the thermal assisted heterogeneous rotational and translational micromotions. Comparing with the 2D liquid of isotropic particles, spherocylinders introduce extra rotational degrees of freedom and destroy packing isotropy and the equivalence between rotational and translational motions. It is found that cooling leads to the stronger dynamical heterogeneity with more cooperative hopping and the stronger retardations of rotational hopping than translational hopping. Under topological constraints from nearly parallel and perpendicular rods of the tetratic phase, longitudinal and transverse translational hopping can occur without rotational hopping, but not the reverse. The empty space trailing a neighboring translational hopping patch is needed for triggering the patch rotational hopping with its translational motion into the empty space. It is the origin for the observed increasing separation of hopping time scales and the one-way coupling between rotational and translational hopping. Strips of longitudinally or transversely aligned rods can be ruptured and reconnected with neighboring strips through buckling, kink formation, and patch rotation, under the unbalanced torques or forces from their neighboring rods and thermal kicks.

  16. Cooling wall

    SciTech Connect

    Nosenko, V.I.

    1995-07-01

    Protecting the shells of blast furnaces is being resolved by installing cast iron cooling plates. The cooling plates become non-operational in three to five years. The problem is that defects occur in manufacturing the cooling plates. With increased volume and intensity of work placed on blast furnaces, heat on the cast iron cooling plates reduces their reliability that limits the interim repair period of blast furnaces. Scientists and engineers from the Ukraine studied this problem for several years, developing a new method of cooling the blast furnace shaft called the cooling wall. Traditional cast iron plates were replaced by a screen of steel tubes, with the area between the tubes filled with fireproof concrete. Before placing the newly developed furnace shaft into operation, considerable work was completed such as theoretical calculations, design, research of temperature fields and tension. Continual testing over many years confirms the value of this research in operating blast furnaces. The cooling wall works with water cooling as well as vapor cooling and is operating in 14 blast furnaces in the Ukraine and two in Russia, and has operated for as long as 14 years.

  17. Search for cool giant exoplanets around young and nearby stars. VLT/NaCo near-infrared phase-coronagraphic and differential imaging

    NASA Astrophysics Data System (ADS)

    Maire, A.-L.; Boccaletti, A.; Rameau, J.; Chauvin, G.; Lagrange, A.-M.; Bonnefoy, M.; Desidera, S.; Sylvestre, M.; Baudoz, P.; Galicher, R.; Mouillet, D.

    2014-06-01

    Context. Spectral differential imaging (SDI) is part of the observing strategy of current and future high-contrast imaging instruments. It aims to reduce the stellar speckles that prevent the detection of cool planets by using in/out methane-band images. It attenuates the signature of off-axis companions to the star, such as angular differential imaging (ADI). However, this attenuation depends on the spectral properties of the low-mass companions we are searching for. The implications of this particularity on estimating the detection limits have been poorly explored so far. Aims: We perform an imaging survey to search for cool (Teff< 1000-1300 K) giant planets at separations as close as 5-10 AU. We also aim to assess the sensitivity limits in SDI data taking the photometric bias into account. This will lead to a better view of the SDI performance. Methods: We observed a selected sample of 16 stars (age <200 Myr, distance <25 pc) with the phase-mask coronagraph, SDI, and ADI modes of VLT/NaCo. Results: We do not detect any companions. As for the estimation of the sensitivity limits, we argue that the SDI residual noise cannot be converted into mass limits because it represents a differential flux, unlike what is done for single-band images, in which fluxes are measured. This results in degeneracies for the mass limits, which may be removed with the use of single-band constraints. We instead employ a method of directly determining the mass limits and compare the results from a combined processing SDI-ADI (ASDI) and ADI. The SDI flux ratio of a planet is the critical parameter for the ASDI performance at close-in separations (≲1''). The survey is sensitive to cool giant planets beyond 10 AU for 65% and 30 AU for 100% of the sample. Conclusions: For close-in separations, the optimal regime for SDI corresponds to SDI flux ratios higher than ~2. According to the BT-Settl model, this translates into Teff ≲ 800 K, which is significantly lower than the methane condensation temperature (~1300 K). The methods described here can be applied to the data interpretation of SPHERE. In particular, we expect better performance with the dual-band imager IRDIS, thanks to more suitable filter characteristics and better image quality. Based on observations collected at the European Southern Observatory, Chile, ESO programs 085.C-0257A, 086.C-0164A, and 088.C-0893A.

  18. Conceptual design study of geothermal district heating of a thirty-house subdivision in Elko, Nevada, using existing water-distribution systems, Phase III. Final technical report, October 1, 1979-September 30, 1980

    SciTech Connect

    Pitts, D.R.

    1980-09-30

    A conceptual design study for district heating of a 30-home subdivision located near the southeast extremity of the city of Elko, Nevada is presented. While a specific residential community was used in the study, the overall approach and methodologies are believed to be generally applicable for a large number of communities where low temperature geothermal fluid is available. The proposed district heating system utilizes moderate temperature, clean domestic water and existing community culinary water supply lines. The culinary water supply is heated by a moderate temperature geothermal source using a single heat exchanger at entry to the subdivision. The heated culinary water is then pumped to the houses in the community where energy is extracted by means of a water supplied heat pump. The use of heat pumps at the individual houses allows economic heating to result from supply of relatively cool water to the community, and this precludes the necessity of supplying objectionably hot water for normal household consumption use. Each heat pump unit is isolated from the consumptive water flow such that contamination of the water supply is avoided. The community water delivery system is modified to allow recirculation within the community, and very little rework of existing water lines is required. The entire system coefficient of performance (COP) for a typical year of heating is 3.36, exclusive of well pumping energy.

  19. Cool Suit

    NASA Technical Reports Server (NTRS)

    1987-01-01

    Acurex developed a heat stress alleviating, liquid cooled helmet liner for military pilots after a series of accidents in Vietnam suggested heat exhaustion as the cause. System pumped a cooled liquid through channels in the helmet liner proved effective in eliminating 40-60% of stored body heat.

  20. School District Mergers: What One District Learned

    ERIC Educational Resources Information Center

    Kingston, Kathleen

    2009-01-01

    Throughout the planning process for a school district merger in a northwestern Pennsylvania school district, effective communication proved to be a challenge. Formed in 1932, this school district of approximately 1400 students was part of a utopian community; one established by a transportation system's corporation that was a major industrial…

  1. School District Mergers: What One District Learned

    ERIC Educational Resources Information Center

    Kingston, Kathleen

    2009-01-01

    Throughout the planning process for a school district merger in a northwestern Pennsylvania school district, effective communication proved to be a challenge. Formed in 1932, this school district of approximately 1400 students was part of a utopian community; one established by a transportation system's corporation that was a major industrial

  2. Laser cooling of molecular anions.

    PubMed

    Yzombard, Pauline; Hamamda, Mehdi; Gerber, Sebastian; Doser, Michael; Comparat, Daniel

    2015-05-29

    We propose a scheme for laser cooling of negatively charged molecules. We briefly summarize the requirements for such laser cooling and we identify a number of potential candidates. A detailed computation study with C_{2}^{-}, the most studied molecular anion, is carried out. Simulations of 3D laser cooling in a gas phase show that this molecule could be cooled down to below 1 mK in only a few tens of milliseconds, using standard lasers. Sisyphus cooling, where no photodetachment process is present, as well as Doppler laser cooling of trapped C_{2}^{-}, are also simulated. This cooling scheme has an impact on the study of cold molecules, molecular anions, charged particle sources, and antimatter physics. PMID:26066432

  3. Cooled railplug

    DOEpatents

    Weldon, William F.

    1996-01-01

    The railplug is a plasma ignitor capable of injecting a high energy plasma jet into a combustion chamber of an internal combustion engine or continuous combustion system. An improved railplug is provided which has dual coaxial chambers (either internal or external to the center electrode) that provide for forced convective cooling of the electrodes using the normal pressure changes occurring in an internal combustion engine. This convective cooling reduces the temperature of the hot spot associated with the plasma initiation point, particularly in coaxial railplug configurations, and extends the useful life of the railplug. The convective cooling technique may also be employed in a railplug having parallel dual rails using dual, coaxial chambers.

  4. Temperature initiated passive cooling system

    DOEpatents

    Forsberg, C.W.

    1994-11-01

    A passive cooling system for cooling an enclosure only when the enclosure temperature exceeds a maximum standby temperature comprises a passive heat transfer loop containing heat transfer fluid having a particular thermodynamic critical point temperature just above the maximum standby temperature. An upper portion of the heat transfer loop is insulated to prevent two phase operation below the maximum standby temperature. 1 fig.

  5. Temperature initiated passive cooling system

    DOEpatents

    Forsberg, Charles W.

    1994-01-01

    A passive cooling system for cooling an enclosure only when the enclosure temperature exceeds a maximum standby temperature comprises a passive heat transfer loop containing heat transfer fluid having a particular thermodynamic critical point temperature just above the maximum standby temperature. An upper portion of the heat transfer loop is insulated to prevent two phase operation below the maximum standby temperature.

  6. Desiccant-based, heat actuated cooling assessment for DHC systems

    SciTech Connect

    DiBella, F.; Patch, K.; Becker, F.

    1989-10-01

    The goal of the project is to perform a conceptual design, systems analysis and case study evaluation of an application of a desiccant-based, heat actuated cooling system in a District Heating System. The results of this study will encourage the deployment of cooler transport temperatures in District Heating Systems. The proposed concept includes a liquid or solid desiccant-based air cooling and drying system that can be integrated with an existing HVAC system. 3 refs., 6 figs.

  7. Cooling system

    SciTech Connect

    Wildfeuer, R.

    1982-06-15

    A cooling system particularly suitable for use in the airconditioning of buildings is described. The system includes: (A) a cooling zone containing a conduit for cooling fluid, the conduit encountering the heat load, means in the conduit for propelling the fluid through the conduit, and cooling fluid in the conduit; (B) a refrigeration zone containing a closed refrigeration circuit for refrigerant, chiller means in the circuit for extracting energy from the refrigerant, means for circulating refrigerant in the circuit and refrigerant in the circuit; and (C) collection means connected to the refrigeration zone for removing energy extracted by the chiller. The cooling and refrigeration zones are connectable through a heat exchanger for transfer of energy between the fluid and the refrigerant and the refrigerant comprises a slurry of ice and water which may be partly stored in a reservoir constituting part of the refrigeration zone. In this system, a reserve cooling capacity can be stored in the reservoir for use during cyclic requirements therefor.

  8. Laser cooling with nanoparticles

    NASA Astrophysics Data System (ADS)

    Nemova, Galina; Soares de Lima Filho, Elton; Loranger, Sebastien; Kashyap, Raman

    2012-10-01

    Theoretical schemes for laser cooling with nanoparticles have been presented and comprehensively investigated. It is shown that specially designed samples based on nanoparticles can be used to improve the process of laser cooling of solids. One of the proposed schemes is based on lead salt colloidal quantum dots (QDs) doped in a glass host. The second one is based on Tm3+ doped oxy fluoride glass ceramic. It has been shown that lead salt colloidal QDs doped in a glass host can operate as artificial atoms. Very short (microsecond range) radiative lifetimes of the excited 1Sh level of PbSe QDs in comparison with the relatively long (millisecond) radiative lifetime of rare-earth (RE) ions allows the cooling process to be accelerated and to use new hosts with relatively high maximum phonon energy, which have so far been considered not suitable for cooling with RE ions. It has been shown that the second sample, which is based on Tm3+ doped oxy fluoride glass ceramic provides the unique combination of high chemical and mechanical stability of the oxide glass, which is important for a number of applications, and the low phonon energy of the fluoride nano-crystals, which trap a majority of Tm3+ ions participating in the cooling process. This is highly beneficial for laser cooling of solids, since the effective embedding of rare-earth ions in the crystalline phase with low phonon energy provides a high quantum efficiency for the 3F4 --> 3H6 transition involved in the cooling cycle in the Tm3+ ions, which is a key parameter for laser cooling of solids.

  9. Phase transitions in the crystals of L- and DL-cysteine on cooling: the role of the hydrogen-bond distortions and the side-chain motions. 2. DL-cysteine.

    PubMed

    Minkov, Vasil S; Tumanov, Nikolay A; Kolesov, Boris A; Boldyreva, Elena V; Bizyaev, Sergei N

    2009-04-16

    Structural strain and a first-order phase transition in the crystalline DL-cysteine on cooling and on reverse heating were followed by Raman spectroscopy and X-ray diffraction. The transition is reversible and has a large hysteresis (over 100 K). The temperature at which the transition is observed depends strongly on the cooling/heating rate. The phase transition is accompanied by crystal fragmentation. The low-temperature phase could be obtained not only as a result of the solid-state transformation in situ as a polycrystalline sample (with strong preferred orientation, or without it, depending on the preparative technique), but also (using an original crystallization technique) as a single crystal of the quality suitable for structural analysis. For the first time, the crystal structure of the low-temperature phase was solved independently by powder and by single-crystal diffraction techniques. The spectral changes were correlated with the precise diffraction data on the intramolecular conformations and the intermolecular hydrogen bonding before and after the phase transition. The role of the distortion of the intermolecular hydrogen bonds and of the motions of the -CH(2)SH side chains in the phase transition is discussed in a comparison with the low-temperature phase transition in L-cysteine, which is of a different type and preserves the single crystals intact (Kolesov et al. J. Phys. Chem. B, 2008, 112 (40), 12827-12839). PMID:19301837

  10. High-resolution rovibrational spectroscopy of jet-cooled phenyl radical: the ν19 out-of-phase symmetric CH stretch.

    PubMed

    Buckingham, Grant T; Chang, Chih-Hsuan; Nesbitt, David J

    2013-10-01

    Phenyl radical has been studied via sub-Doppler infrared spectroscopy in a slit supersonic discharge expansion source, with assignments for the highest frequency b2 out-of-phase C-H symmetric stretch vibration (ν19) unambiguously confirmed by ≤6 MHz (0.0002 cm(-1)) agreement with microwave ground state combination differences of McMahon et al. [Astrophys. J. 2003, 590, L61-64]. Least squares analysis of over 100 resolved rovibrational peaks in the sub-Doppler spectrum to a Watson Hamiltonian yields precision excited-state rotational constants and a vibrational band origin (ν0 = 3071.8915(4) cm(-1)) consistent with a surprisingly small red-shift (0.9 cm(-1)) with respect to Ar matrix isolation studies of Ellison and co-workers [J. Am. Chem. Soc. 2001, 123, 1977]. Nuclear spin weights and inertial defects confirm the vibrationally averaged planarity and (2)A1 rovibronic symmetry of phenyl radical, with analysis of the rotational constants consistent with a modest C2v distortion of the carbon backbone frame due to partial sp rehybridization of the σ C radical-center. Most importantly, despite the number of atoms (N = 11) and vibrational modes (3N - 6 = 27), phenyl radical exhibits a remarkably clean jet cooled high-resolution IR spectrum that shows no evidence of intramolecular vibrational relaxation (IVR) phenomena such as local or nonlocal perturbations due to strongly coupled nearby dark states. This provides strong support for the feasibility of high-resolution infrared spectroscopy in other aromatic hydrocarbon radical systems. PMID:23537501

  11. Cooled railplug

    DOEpatents

    Weldon, W.F.

    1996-05-07

    The railplug is a plasma ignitor capable of injecting a high energy plasma jet into a combustion chamber of an internal combustion engine or continuous combustion system. An improved railplug is provided which has dual coaxial chambers (either internal or external to the center electrode) that provide for forced convective cooling of the electrodes using the normal pressure changes occurring in an internal combustion engine. This convective cooling reduces the temperature of the hot spot associated with the plasma initiation point, particularly in coaxial railplug configurations, and extends the useful life of the railplug. The convective cooling technique may also be employed in a railplug having parallel dual rails using dual, coaxial chambers. 10 figs.

  12. Developing a district energy system in a competitive urban market

    SciTech Connect

    Mitola, J.P.

    1995-09-01

    In two year`s time, Unicorn Thermal Technologies has grown into one of the largest district cooling systems of 25,000 tons with a 1996 plan to grow to 40,000 tons. This growth is attributed to the development and implementation of a marketing and sales plan based on thorough market research and innovative marketing and sales strategies, and the consistent implementation of those strategies. The beginning of the sales effort was focused around the company`s first district cooling facility, However, it quickly grew into a much broader vision as market acceptance increased. Although the district energy industry has often based its message on being a low cost energy provider, market research and early sales experience indicated that customers choose district cooling as a value added service. As customers began to reserve capacity in the first plant, the idea that district cooling is a value added service and not a commodity energy product was continually reinforced through marketing communications. Although this analysis is a review of developing a district energy system in a competitive urban market, it purposely avoids a long winded discussion of head to head competition.

  13. Thermal analysis of n-alkane phase change material mixtures

    SciTech Connect

    Chio, Y.I.; Choi, E.; Lorsch, H.G.

    1991-03-31

    Tests were performed to characterize the thermal behavior of it number of n-alkanes to be used as phase change materials (PCMs) in district cooling applications. Hexadecane and tetradecane were mixed in different fractions, and their thermal behavior was experimentally evaluated. Test results for melting temperature and fusion energy for laboratory grade hexadecane and tetradecane showed good agreement with datain the literature. However, values for commercial grade hexadecane were found to be considerably lower. In the range of temperatures of interest for district cooling, mixtures of tetradecane and hexadecane can be treated as homogeneous substances. However, their heats of fusion are slightly lower than those of the pure substances. Their melting temperatures are also lower by an amount that can be predicted.

  14. A broad spectral feature detected during the cooling phase of a thermonuclear X-ray burst from GRS 1747-312 with Suzaku

    NASA Astrophysics Data System (ADS)

    Iwai, Masachika; Dotani, Tadayasu; Ozaki, Masanobu; Maeda, Yoshitomo; Mori, Hideyuki; Saji, Shigetaka

    2015-08-01

    Precise measurement of the mass-radius relation of a Neutron Star (NS) is crucial to determine the equation of state of the ultra dense matter. Instead of directly measuring the mass and radius, it is often measured the mass-radius ratio, i.e. gravitational redshift at the NS surface, as it is free from the uncertainty to the source distance. If we can detect spectral features in the emission from the NS photosphere, which may be observable during the thermonuclear X-ray bursts, we can directly measure the gravitational redshift. Thus, we are systematically analyzing the Suzaku archival data looking for the thermonuclear X-ray bursts.GRS 1747-312 is a type I X-ray burst source located in the globular cluster Terzan 6. It was observed with Suzaku as a part of Galactic bulge mapping observations in September, 2009, for a total exposure of 45.3 ks. An exceptionally large X-ray burst with photospheric radius expansion was detected during the observation. The burst duration exceeded an hour. Unfortunately, most of the decay of the burst was not observed due to the satellite passage through the South Atlantic Anomaly.We detected a broad feature in the energy spectrum of the burst above 7 keV in its cooling phase. The feature resembled that of an absorption edge, but was significantly smeared. We found that it was best reproduced by a rotation-broadened absorption edge, where the photo-electric absorption edge was smeared by the rapid spin of the NS. The smeared edge may be produced by the dominant products of the X-ray burst, i.e. hydrogen-like Fe (9.28 keV) or Ni (10.78 keV). If this identification is correct, the gravitational red shift would be 1.30+-0.02 or 1.51+-0.02, respectively, corresponding to the NS radius of 10.1+-0.3 or 7.4+-0.1 km, for an assumed NS mass of 1.4 solar mass. Because the absorption edge is not completely smeared out even with the rapid spin of the NS, this can be a powerful tool to measure the gravitational redshift of the NSs.

  15. Data-Driven Districts.

    ERIC Educational Resources Information Center

    LaFee, Scott

    2002-01-01

    Describes the use of data-driven decision-making in four school districts: Plainfield Public Schools, Plainfield, New Jersey; Palo Alto Unified School District, Palo Alto, California; Francis Howell School District in eastern Missouri, northwest of St. Louis; and Rio Rancho Public Schools, near Albuquerque, New Mexico. Includes interviews with the…

  16. Giant zero field cooled spontaneous exchange bias effect in phase separated La{sub 1.5}Sr{sub 0.5}CoMnO{sub 6}

    SciTech Connect

    Krishna Murthy, J.; Venimadhav, A.

    2013-12-16

    We report a giant zero field cooled exchange bias (ZEB) effect (∼0.65 T) in La{sub 1.5}Sr{sub 0.5}CoMnO{sub 6} sample. Magnetic study has revealed a reentrant spin glass ∼90 K, phase separation to spin glass and ferromagnetic phases below 50 K and canted antiferromagnetic transition ∼10 K. A small conventional exchange bias (CEB) is established with the advent of spontaneous phase separation down to 10 K. Giant ZEB and enhanced CEB effects are found only below 10 K and are attributed to the large unidirectional anisotropy at the interface of isothermally field induced ferromagnetic phase and canted antiferromagnetic background.

  17. An Alternative to Laser Cooling

    NASA Astrophysics Data System (ADS)

    Raizen, Mark

    2015-03-01

    Laser cooling has been the standard approach for over thirty years for cooling the translational motion of atoms. While laser cooling is an extremely successful method, it has been limited to a small set of elements in the periodic table. The performance of laser cooling for those elements has saturated in terms of flux of ultra-cold atoms, density, and phase-space density. I report our progress towards the development of an alternative to laser cooling. Our approach relies on magnetic stopping of supersonic beams, an atomic coilgun. A recent advance is the experimental realization of an adiabatic coilgun which preserves phase-space density. Further cooling was demonstrated with a one-way wall, realizing the historic thought experiment of Maxwell's Demon. More recently, we showed how to apply this method to compress atomic phase space with almost no loss of atom number. Our approach is fundamentally different than laser cooling as it does not rely on the momentum of the photon, but rather the photon entropy. I will report on our experimental progress towards this goal, and describe future experiments that will be enabled by this work.

  18. Cool Sportswear

    NASA Technical Reports Server (NTRS)

    1982-01-01

    New athletic wear design based on the circulating liquid cooling system used in the astronaut's space suits, allows athletes to perform more strenuous activity without becoming overheated. Techni-Clothes gear incorporates packets containing a heat-absorbing gel that slips into an insulated pocket of the athletic garment and is positioned near parts of the body where heat transfer is most efficient. A gel packet is good for about one hour. Easily replaced from a supply of spares in an insulated container worn on the belt. The products, targeted primarily for runners and joggers and any other athlete whose performance may be affected by hot weather, include cooling headbands, wrist bands and running shorts with gel-pack pockets.

  19. Methods of beam cooling

    SciTech Connect

    Sessler, A.M.

    1996-02-01

    Diverse methods which are available for particle beam cooling are reviewed. They consist of some highly developed techniques such as radiation damping, electron cooling, stochastic cooling and the more recently developed, laser cooling. Methods which have been theoretically developed, but not yet achieved experimentally, are also reviewed. They consist of ionization cooling, laser cooling in three dimensions and stimulated radiation cooling.

  20. District heating technology characterization case study: Milwaukee, Wisconsin: Final report

    SciTech Connect

    Coughlan, R.T.; Andrews, J.W.; Metz, P.D.

    1988-03-01

    This report describes the work performed under Part II of the project entitled ''District Heating and Cooling Market Potential and Penetration Study,'' whose purpose is to examine the potential of conventional and innovative district heating and cooling (DHC) space conditioning systems in different regions of the country. Part II, ''Implementation and Application of the Conceptual Approach,'' employs the DHC characterization methodology previously developed in Part I of the project to compare the economic feasibility of selected DHC system types in a specific community. The city of Milwaukee, Wisconsin, was chosen as the candidate host community to study several district heating technologies. In all, six district heating system types were selected along with one baseline system. 12 refs., 25 figs., 11 tabs.

  1. A novel electronic cooling concept

    NASA Astrophysics Data System (ADS)

    Ponnappan, R.; Beam, J. E.

    Advanced electrical power conditioning systems for the More Electric Aircraft Initiative involve high currents and high voltages with the attendant waste heat generation and cooling problems. The use of solid state switching devices such as MCTs for these systems will result in power dissipation of several hundred Watts per square centimeter. Conventional forced air or low velocity single phase fluid cooling is inadequate to handle the waste heat dissipation of these high power devices. More advanced and innovative methods of cooling which can use fluids available in the aircraft and also easy to package are sought. A new approach called 'venturi flow cooling concept' is described. It is shown that localized cooling up to 200 W/sq cm is possible at the venturi throat region where the MCTs can be mounted. PAO coolant with Pr = 56 at 40 C can be conveniently used in aircraft.

  2. Solar Heating and Cooling of Buildings: Phase 0. Feasibility and Planning Study. Volume 1: Executive Summary. Document No. 74SD419. Final Report.

    ERIC Educational Resources Information Center

    General Electric Co., Philadelphia, PA. Space Div.

    The purpose of this study was to establish the technical and economic feasibility of using solar energy for the heating and cooling of buildings and to provide baseline information for the widespread application of solar energy. The initial step in this program was a study of the technical, economic, societal, legal, and environmental factors…

  3. REACTOR COOLING

    DOEpatents

    Quackenbush, C.F.

    1959-09-29

    A nuclear reactor with provisions for selectively cooling the fuel elements is described. The reactor has a plurality of tubes extending throughout. Cylindrical fuel elements are disposed within the tubes and the coolant flows through the tubes and around the fuel elements. The fuel elements within the central portion of the reactor are provided with roughened surfaces of material. The fuel elements in the end portions of the tubes within the reactor are provlded with low conduction jackets and the fuel elements in the region between the central portion and the end portions are provided with smooth surfaces of high heat conduction material.

  4. Laser cooling to quantum degeneracy

    NASA Astrophysics Data System (ADS)

    Schreck, Florian

    2013-05-01

    We have created Bose-Einstein condensates (BECs) of strontium using laser cooling as the only cooling method. Our scheme is based on the combination of three techniques, favored by the properties of this element. Using a narrow intercombination transition, we prepare a laser cooled sample of 107 84Sr atoms in a large ``reservoir'' dipole trap at a phase-space density of ~ 0.1. Further increase of the phase-space density has formerly been hindered by detrimental effects of the laser cooling photons, such as an effective repulsion between atoms by multiple scattering. To avoid these effects, we render atoms transparent for these photons in a small spatial region within the laser cooled cloud. Transparency is induced by a light shift on the optically excited state of the laser cooling transition. In the region of transparency, we are able to increase the density of the gas by accumulating atoms in a small ``dimple'' dipole trap. Atoms in the dimple thermalize with the reservoir of laser-cooled atoms by elastic collisions and form a BEC. Condensates of up to 105 atoms can be repeatedly formed on a timescale of 100 ms. Our method opens new prospects for the generation of a continuous atom laser. This work was supported by the Austrian Science Fund (FWF Project No. Y507-N20) and the European Commission (FET-Open Grant No. 250072).

  5. The Kentucky Needs Assessment Study, Phase II. Pilot Project: Developing and Field Testing Performance Measures in Selected School Districts for School Year 1970-71.

    ERIC Educational Resources Information Center

    Kentucky State Dept. of Education, Frankfort.

    The primary goal of the Kentucky Needs Assessment Project is to develop methods of sampling and annually assessing the extent of learners' needs in Kentucky and to stimulate educational programming based on the reduction of learners' needs. The completed Phase I of the project was devoted to an identification of learners' needs and a determination…

  6. Cooling our tomorrows economically

    SciTech Connect

    Watt, J.R. )

    1992-06-01

    This paper reports that summer cooling poses unprecedented problems in the years ahead for architects, engineers, manufacturers, contractors and users. True, millions of tons of fine volcanic ash from the Philippines' Mt. Pinatubo and soot from Kuwait's burned oil wells now encircle the globe, creating temporary shade. The eruption also sent up related weights of sulfur dioxide (convertible to stratospheric sulfate aerosols) for further shading. Together, they may briefly counteract global warming, but rising greenhouse gases guarantee the latter will return with renewed force. Greenhouse gas production continues, making global warming certain, even if all CFCs are phased out, for they are minor greenhouse problems. Cooling loads will increase faster than rising temperatures as populations increase and move south, and as comfort and clean air standards rise. In addition, the fear of skin cancer, cataracts and related retinal and immune system damage may shortly keep more people indoors in summer, thereby raising internal loads.

  7. Lost in Transition: HIV Prevalence and Correlates of Infection among Young People Living in Post-Emergency Phase Transit Camps in Gulu District, Northern Uganda

    PubMed Central

    Patel, Sheetal; Schechter, Martin T.; Sewankambo, Nelson K.; Atim, Stella; Kiwanuka, Noah; Spittal, Patricia M.

    2014-01-01

    Objective Little is known about HIV infection and the related vulnerabilities of young people living in resource-scarce, post-emergency transit camps that are now home to thousands of Internally Displaced Persons (IDPs) following two decades of war in northern Uganda. The objective of this analysis was to assess the prevalence and correlates of HIV infection among young people living in post-conflict transition in Gulu District, northern Uganda. Methods In 2010, a cross-sectional demographic and behavioural survey was conducted in two of Gulu District’s sub-counties with 384 purposively selected transit camp residents aged 15 to 29 years. Biological specimens were collected for rapid HIV testing in the field and confirmatory laboratory testing. Multivariable logistic regression identified independent determinants of HIV infection. Results HIV prevalence was alarmingly high at 12.8% (95% CI: 9.6%, 16.5%). The strongest determinant of HIV infection among young people was a non-consensual sexual debut (adjusted odds ratio [AOR], 9.88; 95% CI: 1.70–18.06). Residing in Awach sub-county (AOR, 2.93; 95% CI: 1.28–6.68), experiencing STI symptoms in the previous 12 months (AOR, 2.36; 95% CI: 1.43–6.17), and practicing dry sex (AOR, 2.31; 95% CI: 1.04–5.13) were other key determinants of HIV infection. Conclusions Study findings contribute to filling an important gap in epidemiological evidence and are useful for planning public health interventions in northern Uganda that effectively target young people in post-conflict transition and support them in the resettlement process. Findings serve to recommend reaching beyond traditional prevention programming in a way more effectively beneficial to young people in post-conflict settings by developing population-specific responses sensitive to local contexts and sufficient to address the underlying causes of the complex risk factors influencing the spread of HIV. PMID:24587034

  8. Leaner Class Sizes Add Fiscal Stress to Florida Districts

    ERIC Educational Resources Information Center

    McNeil, Michele

    2008-01-01

    With a total price tag pushing $10 billion, Florida's "class-size-reduction mandate"--the nation's toughest--is under fire, as school districts call on lawmakers to weaken the 2002 constitutional requirement before it is fully phased in later this year. Starting with the 2008-09 school year, individual districts must meet new size caps in each…

  9. Laser Cooling of Metastable Helium

    NASA Astrophysics Data System (ADS)

    Chuang, Ti.

    An experiment on the laser cooling of a metastable helium beam has been carried out. This experiment is appropriate to be described theoretically under a semiclassical framework. The experiment is the first phase of a large experimental project, whose ultimate goal is to investigate the behavior of laser -cooled metastable helium atoms in the quantum mechanical domain. This first phase is to provide the foundation for the second phase, which will be described in a full quantum mechanical framework. To reach this goal, an atomic beam source and a detection and data acquisition system were designed and constructed to be used in both phases. A laser system that is necessary for the first phase was also designed and constructed. This experiment was designed so that the studies of the atomic behavior, both in the semiclassical and quantum mechanical regions, can be investigated almost simultaneously. This experiment mainly consists of a one-dimensional transverse Doppler cooling of a metastable helium beam. The theory of Doppler cooling, based upon previous work of others, is discussed in this thesis as well. A final velocity width (HWHM) of ~0.62 m/s has been achieved, which is about 2.5 times larger than the Doppler velocity predicted by the theory. The two most likely reasons for not obtaining the Doppler velocity have been carefully examined. Sub-Doppler cooling of the helium beam was also tried, but was unsuccessful. It is our belief that the very same reasons prevent us from achieving sub -Doppler cooling as well.

  10. School District Energy Manual.

    ERIC Educational Resources Information Center

    Association of School Business Officials International, Reston, VA.

    This manual serves as an energy conservation reference and management guide for school districts. The School District Energy Program (SDEP) is designed to provide information and/or assistance to school administrators planning to implement a comprehensive energy management program. The manual consists of 15 parts. Part 1 describes the SDEP; Parts…

  11. District, Know Thyself

    ERIC Educational Resources Information Center

    Tupa, Megan; McFadden, Ledyard

    2009-01-01

    Finalists for the Broad Prize for Urban Education demonstrate that identifying strategies that fit the local context is essential in creating success for students. Long Beach Unified School District in California and Broward County Public Schools in Florida demonstrate how districts can use different strategies to achieve the same goals.

  12. Rescuing Distressed Districts.

    ERIC Educational Resources Information Center

    Stainbrook, Ronald

    1994-01-01

    Two Pennsylvania school districts have been simultaneously declared financially "distressed" and are operated by a court-appointed board of control. Describes legislation drafted to statutorily establish an early warning system so that the state can assist districts with management and budgeting advice before it becomes necessary to appoint a…

  13. Do School Districts Matter?

    ERIC Educational Resources Information Center

    Whitehurst, Grover J.; Chingos, Matthew M.; Gallaher, Michael R.

    2013-01-01

    School districts occupy center stage in education reform in the U.S. They manage nearly all public funding and are frequently the locus of federal and state reform initiatives, e.g., instituting meaningful teacher evaluation systems. Financial compensation for district leaders is high, with many being paid more than the chief state school officers…

  14. Pressure drop, heat transfer, critical heat flux, and flow stability of two-phase flow boiling of water and ethylene glycol/water mixtures - final report for project "Efficent cooling in engines with nucleate boiling."

    SciTech Connect

    Yu, W.; France, D. M.; Routbort, J. L.

    2011-01-19

    Because of its order-of-magnitude higher heat transfer rates, there is interest in using controllable two-phase nucleate boiling instead of conventional single-phase forced convection in vehicular cooling systems to remove ever increasing heat loads and to eliminate potential hot spots in engines. However, the fundamental understanding of flow boiling mechanisms of a 50/50 ethylene glycol/water mixture under engineering application conditions is still limited. In addition, it is impractical to precisely maintain the volume concentration ratio of the ethylene glycol/water mixture coolant at 50/50. Therefore, any investigation into engine coolant characteristics should include a range of volume concentration ratios around the nominal 50/50 mark. In this study, the forced convective boiling heat transfer of distilled water and ethylene glycol/water mixtures with volume concentration ratios of 40/60, 50/50, and 60/40 in a 2.98-mm-inner-diameter circular tube has been investigated in both the horizontal flow and the vertical flow. The two-phase pressure drop, the forced convective boiling heat transfer coefficient, and the critical heat flux of the test fluids were determined experimentally over a range of the mass flux, the vapor mass quality, and the inlet subcooling through a new boiling data reduction procedure that allowed the analytical calculation of the fluid boiling temperatures along the experimental test section by applying the ideal mixture assumption and the equilibrium assumption along with Raoult's law. Based on the experimental data, predictive methods for the two-phase pressure drop, the forced convective boiling heat transfer coefficient, and the critical heat flux under engine application conditions were developed. The results summarized in this final project report provide the necessary information for designing and implementing nucleate-boiling vehicular cooling systems.

  15. New directions for district heating in the United States

    SciTech Connect

    Olszewski, M.; Karnitz, M.A.

    1981-01-01

    Within the past five years there has been a growing awareness of the energy conservation and economic advantages of modern hot-water district heating systems. A description is given of the status of major US district heating projects and the potential impact of the newly implemented US National District Heating Plan is examined. At the present time there are five major district heating projects moving into the construction and demonstration phase. Although all have hot water distribution systems a variety of heat sources are being utilized. These heat sources include geothermal water, industrial reject heat, and utility cogeneration using coal-fired power plants.

  16. Cab Heating and Cooling

    SciTech Connect

    Damman, Dennis

    2005-10-31

    Schneider National, Inc., SNI, has concluded the Cab Heating and Cooling evaluation of onboard, engine off idling solutions. During the evaluation period three technologies were tested, a Webasto Airtronic diesel fired heater for cold weather operation, and two different approaches to cab cooling in warm weather, a Webasto Parking Cooler, phase change storage system and a Bergstrom Nite System, a 12 volt electrical air conditioning approach to cooling. Diesel fired cab heaters were concluded to provide adequate heat in winter environments down to 10 F. With a targeted idle reduction of 17%, the payback period is under 2 years. The Webasto Parking Cooler demonstrated the viability of this type of technology, but required significant driver involvement to achieve maximum performance. Drivers rated the technology as ''acceptable'', however, in individual discussions it became apparent they were not satisfied with the system limitations in hot weather, (over 85 F). The Bergstrom Nite system was recognized as an improvement by drivers and required less direct driver input to operate. While slightly improved over the Parking Cooler, the hot temperature limitations were only slightly better. Neither the Parking Cooler or the Nite System showed any payback potential at the targeted 17% idle reduction. Fleets who are starting at a higher idle baseline may have a more favorable payback.

  17. Building a Construction Curriculum for Your School District

    ERIC Educational Resources Information Center

    Ruder, Robert

    2010-01-01

    Embracing the notion of going green, an affluent school district in Pennsylvania spent $83 million as part of the high school's renovation and expansion project. The three-level addition is now equipped with self-dimming lights, energy-efficient windows, a rooftop solar water heater, and a geothermal cooling and heating system. As a bonus for…

  18. Principles and applications of muon cooling

    SciTech Connect

    Neuffer, D.

    1983-01-01

    The basic principles of the application of ionization cooling to obtain high phase-space density muon beams are described, and its limitations are outlined. Sample cooling scenarios are presented. Applications of cooled muon beams in high-energy accelerators are suggested; high-luminosity ..mu../sup +/-..mu../sup -/ and ..mu..-p colliders at greater than or equal to -TeV energy are possible.

  19. Microseismic monitoring for evidence of geothermal heat in the capital district of New York. Volume 5. Phases I-III. Final report

    SciTech Connect

    Not Available

    1983-06-01

    The seismic monitoring aspect of this work consisted of setting up and operating a network of seven seismograph stations within and around the study area capable of detecting and locating small earthquakes. To supplement the evidence from present day seismic activity, a list of all known historical and early instrumental earthquakes was compiled and improved from original sources for a larger region centered on the study area. Additional field work was done to determine seismic velocities of P and S phases by special recording of quarry blasts. The velocity results were used both as an aid to improve earthquake locations based on computer programs and to make inferences about the existence of temperature anomalies, and hence geothermal potential, at depths beneath the study area. Finally, the level in the continuous background earth vibration, microseisms, was measured throughout the study area to test a possibility that a relationship may exist at the surface between the level in microseisms and the geothermal or related activity. The observed seismic activity within the study area, although considerably higher (two to three times) than inferred from the historical and early instrumental data, is still not only low for a potential geothermal area but appears to be related to coherent regional tectonic stresses and not to the proposed more localized geothermal activity reflected in the mineralized, CO/sub 2/ rich spring discharge.

  20. The Effect of the Rate of Cooling from High-Temperature Single-Phase Region on the Microstructure and Magnetic Properties of AlNi Alloys

    NASA Astrophysics Data System (ADS)

    Menushenkov, Vladimir P.; Gorshenkov, Mikhail V.; Savchenko, Elena S.; Zhukov, Dmitry G.

    2015-02-01

    The microstructure of as-cast and melt spun AlNi alloys was studied by transmission (TEM) and scanning electron microscopy as well as atomic force microscopy (AFM). The magnetic properties of the alloys were measured using a vibrating sample magnetometer. The water quenched and melt spun AlNi samples were characterized by zone microstructure formed as a result of solid solution decomposition into β- and β2 phases within the miscibility gap. Therefore, the subsequent aging of as-quenched alloy leads to the development of the zone microstructure instead of the decomposition of single-phase solid solution. The absence of preferential precipitations and discontinuous precipitation (DP) reaction was observed at grain boundaries (GB) of as-cast AlNi alloy after aging. The antiphase domains (APD) have been observed for the first time in the AlNi ribbons prepared by melt spinning. The effects of GB and APD boundaries on the decomposition of a solid solution in the AlNi ribbons were investigated. At first, a thin β-phase layer is formed along GB and APD boundaries. Then the decomposition leads to the formation of β2-phase layers on the both sides of β-phase layer. The GB and APD boundaries, which are decorated by precipitates of β- and β2 layers, become visible in the TEM and AFM micrographs. A DP reaction at GBs has been observed for the first time in the AlNi ribbons after supplementary aging. The cellular microstructure at GBs consisting of alternating lamellas of β'- and β'2 phases was formed after aging the ribbons at 773 K (500 °C) for 10 minutes.

  1. Rectlinear cooling scheme for bright muon sources

    SciTech Connect

    Stratakis, Diktys

    2015-05-03

    A fast cooling technique is described that simultaneously reduces all six phase-space dimensions of a charged particle beam. In this process, cooling is accomplished by reducing the beam momentum through ionization energy loss in absorbers and replenishing the momentum loss only in the longitudinal direction rf cavities. In this work we review its main features and describe the main results.

  2. Heating and cooling of the interstellar gas

    NASA Technical Reports Server (NTRS)

    Black, John H.

    1987-01-01

    Basic considerations of the global heating and cooling of the interstellar gas are summarized. The various energy sources are reviewed. Expressions for the rates of a number of typical heating and cooling processes are given. General comments are made about the conditions in the several phases of the interstellar medium in thermal balance.

  3. Alfvén wave phase-mixing in flows. Why over-dense, solar coronal, open magnetic field structures are cool

    NASA Astrophysics Data System (ADS)

    Tsiklauri, D.

    2016-02-01

    Aims: The motivation for this study is to include the effect of plasma flow in Alfvén wave (AW) damping via phase mixing and to explore the observational implications. Methods: Our magnetohydrodynamic simulations and analytical calculations show that, when a background flow is present, mathematical expressions for the AW damping via phase mixing are modified by the following substitution: CA' (x) → CA' (x) + V0' (x), where CA and V0 are AW phase and the flow speeds, and the prime denotes a derivative in the direction across the background magnetic field. Results: In uniform magnetic fields and over-dense plasma structures, where CA is smaller than in the surrounding plasma, the flow, which is confined to the structure and going in the same direction as the AW, reduces the effect of phase-mixing, because on the edges of the structure CA' and V0' have opposite signs. Thus, the wave damps by means of slower phase-mixing compared to the case without the flow. This is the result of the co-directional flow that reduces the wave front stretching in the transverse direction. Conversely, the counter-directional flow increases the wave front stretching in the transverse direction, therefore making the phase-mixing-induced heating more effective. Although the result is generic and is applicable to different laboratory or astrophysical plasma systems, we apply our findings to addressing the question why over-dense solar coronal open magnetic field structures (OMFS) are cooler than the background plasma. Observations show that the over-dense OMFS (e.g. solar coronal polar plumes) are cooler than surrounding plasma and that, in these structures, Doppler line-broadening is consistent with bulk plasma motions, such as AW. Conclusions: If over-dense solar coronal OMFS are heated by AW damping via phase-mixing, we show that, co-directional with AW, plasma flow in them reduces the phase-mixing induced-heating, thus providing an explanation of why they appear cooler than the background.

  4. Geothermal District Heating Economics

    Energy Science and Technology Software Center (ESTSC)

    1995-07-12

    GEOCITY is a large-scale simulation model which combines both engineering and economic submodels to systematically calculate the cost of geothermal district heating systems for space heating, hot-water heating, and process heating based upon hydrothermal geothermal resources. The GEOCITY program simulates the entire production, distribution, and waste disposal process for geothermal district heating systems, but does not include the cost of radiators, convectors, or other in-house heating systems. GEOCITY calculates the cost of district heating basedmore » on the climate, population, and heat demand of the district; characteristics of the geothermal resource and distance from the distribution center; well-drilling costs; design of the distribution system; tax rates; and financial conditions.« less

  5. District heating and cooling: feasibility study, City of Cambridge

    SciTech Connect

    Not Available

    1982-07-01

    The initial task of the project was to gather library and reference materials. The team evaluated existing heat sources and heat requirements. The next step was to assess the economic and technical feasibility of alternative DHC projects from economic, environmental, employment, conservation, and community development objective perspectives. Institutional factors were assessed, including ownership, financing, and regulatory attitudes. This report is divided into six distinct segments. They are: Conclusions and Recommendations, Background, Methodology, Findings, and a brief Implementation Plan.

  6. Geothermal district G1

    SciTech Connect

    Not Available

    1988-12-01

    Geothermal District G1 includes 37 northeastern California counties and six geothermal fields: Lake City, Susanville, Litchfield, Wendel, Amedee, and Casa Diablo. Electrical generation from geothermal resources occurs in three of the fields: Wendel, Amedee, and Casa Diablo. Low-temperature geothermal projects are underway throughout the district and are described in a road log format. The ten projects described are located at Big Bend, Glass Mountain, Bieber, Alturas, Cedarville, Lake City, Honey Lake Valley, Greenville, and in Sierra and Mono Counties.

  7. Comments on optical stochastic cooling

    SciTech Connect

    K.Y. Ng, S.Y. Lee and Y.K. Zhang

    2002-10-08

    An important necessary condition for transverse phase space damping in the optical stochastic cooling with transit-time method is derived. The longitudinal and transverse damping dynamics for the optical stochastic cooling is studied. The authors also obtain an optimal laser focusing condition for laser-beam interaction in the correction undulator. The amplification factor and the output peak power of the laser amplifier are found to differ substantially from earlier publications. The required power is large for hadron colliders at very high energy.

  8. Magneto-optical cooling of atoms.

    PubMed

    Raizen, Mark G; Budker, Dmitry; Rochester, Simon M; Narevicius, Julia; Narevicius, Edvardas

    2014-08-01

    We propose an alternative method to laser cooling. Our approach utilizes the extreme brightness of a supersonic atomic beam, and the adiabatic atomic coilgun to slow atoms in the beam or to bring them to rest. We show how internal-state optical pumping and stimulated optical transitions, combined with magnetic forces, can be used to cool the translational motion of atoms. This approach does not rely on momentum transfer from photons to atoms, as in laser cooling. We predict that our method can surpass laser cooling in terms of flux of ultracold atoms and phase-space density, with lower required laser power. PMID:25078213

  9. Apatite Chemistry in a Felsic Magmatic System From the El Teniente District (Chile) as Monitor of an Early, Single-phase, Cl and S-rich Magmatic Volatile Phase Evolution.

    NASA Astrophysics Data System (ADS)

    Hernandez, L. B.; Rabbia, O. M.

    2009-05-01

    Apatite (Ap) is a ubiquitous accessory mineral phase in igneous rocks, that can incorporate several geochemically important elements among which are volatiles as Cl, H2O, S, As, F. Furthermore, as Ap starts to crystallize early in felsic magmas, and continue through a wide temperature range, it can potentially be used to monitor the evolution of magmatic volatiles in porphyry copper systems. In this work, we have studied magmatic Ap from Late Miocene dacitic porphyries spatially and temporally associated to the Cu-(Mo) La Huifa- La Negra prospect (4 km NE from the giant El Teniente porphyry copper deposit, Chile). These felsic rocks formed from hydrous magmas as indicated by early crystallized Hb (before Bt). Al-Hb geobarometer indicates that phenocrysts formed at 2 Kb, while fine grained groundmass suggests a depressurization. Ap is present as small (10-50 microns) subhedral to euhedral prisms included in Fe-Ti oxides, plagioclase, amphibole and biotite phenocrysts (IAp), and as bigger (up to 300 microns) isolated microphenocrysts (MAp), indicating crystallization throughout magmatic evolution. About 300 EPM analyses of Cl, F and SO3 have been performed on Ap in different textural positions. Only Ap included in anhydrous phases (mostly Pl and oxides) and unaltered grains from the groundmass were used to evaluate volatile evolution. Calculated apatite saturation temperature following Piccoli and Candela (1994) indicates that they started to crystallize 900C. The most outstanding chemical feature of the studied Ap is their high Cl (up to 4.52 wt%) and SO3 (up to 0.98 wt%) contents, being highest in IAp. Cl/F and Cl/OH strongly decrease from ApI to MAp within all studied samples varying in SiO2 content from 66.3 to 69.7 wt%. They display a continuous and well defined trend. This variation is controlled mainly by Cl decrease and F increase, meanwhile OH remains roughly constant. SO3 in Ap varies from 0.98wt% in IAp to below detection limit (0.02 wt% SO3) in MAp. S and Cl in Ap show a general positive correlation being their contents in IAp higher than those in MAp. The results are consistent with Ap starting to crystallize at 2Kb, in equilibrium with an early formed, high temperature, highly saline S-rich magmatic volatile phase that evolved toward less saline less S-rich compositions. The strong decrease of Cl/OH as F increases indicates that the exsolved volatile phase is a single phase (supercritical), in agreement with its P and T of formation. High sulfur contents in IAp suggest the host magma was sulfate-rich, and thus oxidized as it's also suggested by high Mg# (0.66-0.75) in primary ferromagnesian minerals. Sulfur presence, along with Cl, would enhance metal (Cu) partitioning from melt into magmatic volatile phase (Simon et al, 2006), while low crystal charge prevailing during early volatile exsolution would favour coalescence and upward migration processes, to finally accumulation in upper parts of the system. Thus, the aqueous Cl and S-rich fluids exsolved, at high pressure (2 Kb), upon magma differentiation at La Huifa-La Negra prospect, could have efficiently extracted metals from the magma and hence, it would have the potential to create a hydrothermal ore deposit provided that the magma was not erupted and that the necessary conditions for subsequent ore deposition prevailed. This is a contribution to DIUC 203-320-013-1 Piccoli, P. and Candela, P. 1994. Am. J. of Sc., 294, 92-135. Simon, A.C., Pettke, T., Candela, P., Piccoli, P. y Heinrich, C.A., 2006. GCA, 70, 5583-5600.

  10. Cooling of Kilauea Iki lava lake

    SciTech Connect

    Hills, R.G.

    1982-02-01

    In 1959 Kilauea Iki erupted leaving a 110 to 120 m lake of molten lava in its crater. The resulting lava lake has provided a unique opportunity to study the cooling dynamics of a molten body and its associated hydrothermal system. Field measurements taken at Kilauea Iki indicate that the hydrothermal system above the cooling magma body goes through several stages, some of which are well modeled analytically. Field measurements also indicate that during most of the solidification period of the lake, cooling from above is controlled by 2-phase convection while conduction dominates the cooling of the lake from below. A summary of the field work related to the study of the cooling dynamics of Kilauea Iki is presented. Quantitative and qualitative cooling models for the lake are discussed.

  11. Cooling rates of group IVA iron meteorites

    NASA Technical Reports Server (NTRS)

    Willis, J.; Wasson, J. T.

    1978-01-01

    Cooling rates of six group IVA iron meteorites were estimated by a taenite central Ni concentration-taenite half-width method. Calculated cooling rates range from 13 to 25 C/Myr, with an average of 20 C/Myr. No correlation between cooling rate and bulk Ni content is observed, and the data appear to be consistent with a uniform cooling rate as expected from an igneous core origin. This result differs from previous studies reporting a wide range in cooling rates that were strongly correlated with bulk Ni content. The differences result mainly from differences in the phase diagram and the selected diffusion coefficients. Cooling rates inferred from taenite Ni concentrations at the interface with kamacite are consistent with those based on taenite central Ni content.

  12. Laser cooling without spontaneous emission.

    PubMed

    Corder, Christopher; Arnold, Brian; Metcalf, Harold

    2015-01-30

    This Letter reports the demonstration of laser cooling without spontaneous emission, and thereby addresses a significant controversy. It works by restricting the atom-light interaction to a time short compared to a cycle of absorption followed by natural decay. It is achieved by using the bichromatic force on an atomic transition with a relatively long excited state lifetime and a relatively short cooling time so that spontaneous emission effects are minimized. The observed width of the one-dimensional velocity distribution is reduced by ×2 thereby reducing the "temperature" by ×4. Moreover, our results comprise a compression in phase space because the spatial expansion of the atomic sample is limited. This accomplishment is of interest to direct laser cooling of molecules or in experiments where working space or time is limited. PMID:25679888

  13. ASTROMAG coil cooling study

    NASA Technical Reports Server (NTRS)

    Maytal, Ben-Zion; Vansciver, Steven W.

    1990-01-01

    ASTROMAG is a planned particle astrophysics magnetic facility. Basically it is a large magnetic spectrometer outside the Earth's atmosphere for an extended period of time in orbit on a space station. A definition team summarized its scientific objectives assumably related to fundamental questions of astrophysics, cosmology, and elementary particle physics. Since magnetic induction of about 7 Tesla is desired, it is planned to be a superconducting magnet cooled to liquid helium 2 temperatures. The general structure of ASTROMAG is based on: (1) two superconducting magnetic coils, (2) dewar of liquid helium 2 to provide cooling capability for the magnets; (3) instrumentation, matter-anti matter spectrometer (MAS) and cosmic ray isotope spectrometer (CRIS); and (4) interfaces to the shuttle and space station. Many configurations of the superconducting magnets and the dewar were proposed and evaluated, since those are the heart of the ASTROMAG. Baseline of the magnet configuration and cryostat as presented in the phase A study and the one kept in mind while doing the present study are presented. ASTROMAG's development schedule reflects the plan of launching to the space station in 1995.

  14. Thermal analysis of n-alkane phase change material mixtures. Progress report, January 1, 1991--March 31, 1991

    SciTech Connect

    Chio, Y.I.; Choi, E.; Lorsch, H.G.

    1991-03-31

    Tests were performed to characterize the thermal behavior of it number of n-alkanes to be used as phase change materials (PCMs) in district cooling applications. Hexadecane and tetradecane were mixed in different fractions, and their thermal behavior was experimentally evaluated. Test results for melting temperature and fusion energy for laboratory grade hexadecane and tetradecane showed good agreement with datain the literature. However, values for commercial grade hexadecane were found to be considerably lower. In the range of temperatures of interest for district cooling, mixtures of tetradecane and hexadecane can be treated as homogeneous substances. However, their heats of fusion are slightly lower than those of the pure substances. Their melting temperatures are also lower by an amount that can be predicted.

  15. Evidence of the existence of the high-density and low-density phases in deeply-cooled confined heavy water under high pressures

    SciTech Connect

    Wang, Zhe; Chen, Sow-Hsin; Liu, Kao-Hsiang; Harriger, Leland; Leo, Juscelino B.

    2014-07-07

    The average density of D{sub 2}O confined in a nanoporous silica matrix (MCM-41-S) is studied with neutron scattering. We find that below ?210 K, the pressure-temperature plane of the system can be divided into two regions. The average density of the confined D{sub 2}O in the higher-pressure region is about 16% larger than that in the lower-pressure region. These two regions could represent the so-called low-density liquid and high-density liquid phases. The dividing line of these two regions, which could represent the associated 1st order liquid-liquid transition line, is also determined.

  16. How do pseudoenantiomers structurally differ in the gas phase? An IR/UV spectroscopy study of jet-cooled hydroquinine and hydroquinidine.

    PubMed

    Sen, Ananya; Lepere, Valeria; Le Barbu-Debus, Katia; Zehnacker, Anne

    2013-10-21

    The gas-phase structures of the cinchona alkaloids, hydroquinine and its pseudoenantiomer hydroquinidine, are studied in a supersonic expansion by means of laser-induced fluorescence and IR/UV double-resonance spectroscopy. Vibrational spectroscopy combined with density functional calculations show that the conformational properties of the two pseudoenantiomers are identical. In both cases, they exist in two isoenergetic forms, with similar IR spectra. Both conformers are similar to the most stable cis-γ-open form of quinine; they differ from each other by the position of the ethyl substituent attached to the quinuclidine ring. Further differences between the two conformers are observed in the laser-induced fluorescence spectrum. The first electronic transition is characterized by time-dependent density functional theory and RI-cc2 calculations, and is of ππ* nature. The results described here emphasize the role of the ethyl substituent in the structural differences between pseudoenantiomers of cinchona alkaloids. PMID:24106030

  17. Restaurant food cooling practices.

    PubMed

    Brown, Laura Green; Ripley, Danny; Blade, Henry; Reimann, Dave; Everstine, Karen; Nicholas, Dave; Egan, Jessica; Koktavy, Nicole; Quilliam, Daniela N

    2012-12-01

    Improper food cooling practices are a significant cause of foodborne illness, yet little is known about restaurant food cooling practices. This study was conducted to examine food cooling practices in restaurants. Specifically, the study assesses the frequency with which restaurants meet U.S. Food and Drug Administration (FDA) recommendations aimed at reducing pathogen proliferation during food cooling. Members of the Centers for Disease Control and Prevention's Environmental Health Specialists Network collected data on food cooling practices in 420 restaurants. The data collected indicate that many restaurants are not meeting FDA recommendations concerning cooling. Although most restaurant kitchen managers report that they have formal cooling processes (86%) and provide training to food workers on proper cooling (91%), many managers said that they do not have tested and verified cooling processes (39%), do not monitor time or temperature during cooling processes (41%), or do not calibrate thermometers used for monitoring temperatures (15%). Indeed, 86% of managers reported cooling processes that did not incorporate all FDA-recommended components. Additionally, restaurants do not always follow recommendations concerning specific cooling methods, such as refrigerating cooling food at shallow depths, ventilating cooling food, providing open-air space around the tops and sides of cooling food containers, and refraining from stacking cooling food containers on top of each other. Data from this study could be used by food safety programs and the restaurant industry to target training and intervention efforts concerning cooling practices. These efforts should focus on the most frequent poor cooling practices, as identified by this study. PMID:23212014

  18. Plugging of cooling holes in film-cooled turbine vanes

    NASA Technical Reports Server (NTRS)

    Deadmore, D. L.; Lowell, C. E.

    1977-01-01

    The plugging of vane cooling holes by impurities in a marine gas turbine was closely simulated in burner rig tests where dopants were added to the combustion products of a clean fuel (Jet-A). Hole plugging occurred when liquid phases, resulting from the dopants, were present in the combustion products. Increasing flame temperature and dopant concentration resulted in an increased rate of deposition and hole plugging.

  19. Adiabatic cooling of antiprotons.

    PubMed

    Gabrielse, G; Kolthammer, W S; McConnell, R; Richerme, P; Kalra, R; Novitski, E; Grzonka, D; Oelert, W; Sefzick, T; Zielinski, M; Fitzakerley, D; George, M C; Hessels, E A; Storry, C H; Weel, M; Müllers, A; Walz, J

    2011-02-18

    Adiabatic cooling is shown to be a simple and effective method to cool many charged particles in a trap to very low temperatures. Up to 3×10(6) p are cooled to 3.5 K-10(3) times more cold p and a 3 times lower p temperature than previously reported. A second cooling method cools p plasmas via the synchrotron radiation of embedded e(-) (with many fewer e(-) than p in preparation for adiabatic cooling. No p are lost during either process-a significant advantage for rare particles. PMID:21405511

  20. Adiabatic Cooling of Antiprotons

    SciTech Connect

    Gabrielse, G.; Kolthammer, W. S.; McConnell, R.; Richerme, P.; Kalra, R.; Novitski, E.; Oelert, W.; Grzonka, D.; Sefzick, T.; Zielinski, M.; Fitzakerley, D.; George, M. C.; Hessels, E. A.; Storry, C. H.; Weel, M.; Muellers, A.; Walz, J.

    2011-02-18

    Adiabatic cooling is shown to be a simple and effective method to cool many charged particles in a trap to very low temperatures. Up to 3x10{sup 6} p are cooled to 3.5 K--10{sup 3} times more cold p and a 3 times lower p temperature than previously reported. A second cooling method cools p plasmas via the synchrotron radiation of embedded e{sup -} (with many fewer e{sup -} than p) in preparation for adiabatic cooling. No p are lost during either process--a significant advantage for rare particles.

  1. COOLING FORCE MEASUREMENTS IN CELSIUS.

    SciTech Connect

    GALNANDER, B.; FEDOTOV, A.V.; LITVINENKO, V.N.; ET AL.

    2005-09-18

    The design of future high energy coolers relies heavily on extending the results of cooling force measurements into new regimes by using simulation codes. In order to carefully benchmark these codes we have accurately measured the longitudinal friction force in CELSIUS by recording the phase shift between the beam and the RF voltage while varying the RF frequency. Moreover, parameter dependencies on the electron current, solenoid magnetic field and magnetic field alignment were carried out.

  2. Cooling Force Measurements at CELSIUS

    SciTech Connect

    Ga ring lnander, B.; Lofnes, T.; Ziemann, V.; Fedotov, A. V.; Litvinenko, V. N.; Sidorin, A. O.; Smirnov, A. V.

    2006-03-20

    The design of future high energy coolers relies heavily on extending the results of cooling force measurements into new regimes by using simulation codes. In order to carefully benchmark these codes we have accurately measured the longitudinal friction force in CELSIUS by recording the phase shift between the beam and the RF voltage while varying the RF frequency. Moreover, parameter dependencies on the electron current, solenoid magnetic field and magnetic field alignment were carried out.

  3. Competency: District Views from Southern California.

    ERIC Educational Resources Information Center

    Tyo, John

    1979-01-01

    Educators from Fullerton Union High School District, Newport-Mesa Unified School District, Capistrano Unified School District, and Huntington Beach Union High School District describe their efforts toward developing competency-based curriculum to meet state mandates. (SJL)

  4. Districts for 104th Congress

    USGS Publications Warehouse

    U.S. Bureau of the Census

    1990-01-01

    This is a polygon coverage of 104th Congressional District boundaries obtained from the U.S. Bureau of the Census. The 103rd Congress was the first Congress that reflected the reapportionment and delineation of congressional districts based on the 1990 census. The next (104th) Congress reflects redelineation of districts that occurred for six states: Georgia, Louisiana, Maine, Minnesota, South Carolina, and Virginia. Congressional Districts U.S. House of Representatives Census TIGER/Line Files

  5. Liquid-Cooled Garment

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A liquid-cooled bra, offshoot of Apollo moon suit technology, aids the cancer-detection technique known as infrared thermography. Water flowing through tubes in the bra cools the skin surface to improve resolution of thermograph image.

  6. Liquid cooled garments

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Liquid cooled garments employed in several applications in which severe heat is encountered are discussed. In particular, the use of the garments to replace air line cooling units in a variety of industrial processing situations is discussed.

  7. Debuncher Cooling Performance

    SciTech Connect

    Derwent, P. F.; McGinnis, David; Pasquinelli, Ralph; Vander Meulen, David; Werkema, Steven

    2006-03-20

    We present measurements of the Fermilab Debuncher momentum and transverse cooling systems. These systems use liquid helium cooled waveguide pickups and slotted waveguide kickers covering the frequency range 4-8 GHz.

  8. Debuncher cooling performance

    SciTech Connect

    Derwent, P.F.; McGinnis, David; Pasquinelli, Ralph; Vander Meulen, David; Werkema, Steven; /Fermilab

    2005-11-01

    We present measurements of the Fermilab Debuncher momentum and transverse cooling systems. These systems use liquid helium cooled waveguide pickups and slotted waveguide kickers covering the frequency range 4-8 GHz.

  9. "Strategic Review of FY06 District & School-Level Resources". In Fulfillment of a Memorandum of Understanding between: The Los Angeles Unified School District (LAUSD) and The Unified Teachers of Los Angeles (UTLA). Phase II- Final ERS Report. An Executive Summary and Management Brief Series

    ERIC Educational Resources Information Center

    Frank, Stephen; Travers, Jonathan

    2007-01-01

    In the fall of 2006, Los Angeles Unified School District (LAUSD) and the Unified Teachers of Los Angeles (UTLA) signed a memorandum of understanding (MOU) that called for a third-party research firm to analyze resource use across the Los Angeles school system. Education Resource Strategies (ERS) was chosen to conduct this analysis. The study was…

  10. Alternative institutional vehicles for geothermal district heating

    SciTech Connect

    Bressler, S.; Gardner, T.C.; King, D.; Nimmons, J.T.

    1980-06-01

    The attributes of various institutional entities which might participate in various phases of geothermal heating applications are described. Public entities considered include cities, counties, and special districts. Private entities discussed include cooperative organizations and non-member-owned private enterprises. The powers, authority and manner of operation of each of the institutional entities are reviewed. Some of the public utility regulatory implications which may affect choices among available alternatives are considered. (MHR)

  11. Rightsizing a School District

    ERIC Educational Resources Information Center

    Esselman, Mary; Lee-Gwin, Rebecca; Rounds, Michael

    2012-01-01

    The transformation of the Kansas City, Missouri Public Schools (KCMSD) has been long overdue. Multiple superintendents and administrations, using billions of dollars of desegregation funds ventured to transform the district by creating magnet schools, themed schools, and career-focused high schools. Missing from these initiatives, but included in

  12. Districts Shun Stimulus Bids

    ERIC Educational Resources Information Center

    Maxwell, Lesli A.

    2010-01-01

    In the final sprint to polish Race to the Top applications, hundreds of school districts shunned a shot at a share of $4 billion in grants by refusing to sign on to their states' plans for the federal competition. California officials had secured the signatures of 790 local education agencies (leas) late last week, including most of the state's

  13. Districts Tackling Meal Debt

    ERIC Educational Resources Information Center

    Shah, Nirvi

    2012-01-01

    School districts have resorted to hiring debt collectors, employing constables, and swapping out standard meals for scaled-back versions to try to coerce parents to pay off school lunch debt that, in recent years, appears to have surged as the result of a faltering economy and better record-keeping. While the average school lunch costs just about…

  14. Districts Weigh Obesity Screening

    ERIC Educational Resources Information Center

    Butler, Kevin

    2008-01-01

    Parents of children in most elementary grades in Minnesota's Independent School District 191 receive an annual notice with potentially life-altering data for their children--and they are not state test scores, attendance rates, or grades. The notice contains the child's body mass index (BMI) score, which estimates whether the student has excess

  15. Rightsizing a School District

    ERIC Educational Resources Information Center

    Esselman, Mary; Lee-Gwin, Rebecca; Rounds, Michael

    2012-01-01

    The transformation of the Kansas City, Missouri Public Schools (KCMSD) has been long overdue. Multiple superintendents and administrations, using billions of dollars of desegregation funds ventured to transform the district by creating magnet schools, themed schools, and career-focused high schools. Missing from these initiatives, but included in…

  16. School District Spending.

    ERIC Educational Resources Information Center

    Minnesota State Office of the Legislative Auditor, St. Paul. Program Evaluation Div.

    Minnesota spends more for education than most states and has increased its financial commitment steadily over the past 15 years. Because of the state's dominant role in education funding, legislators have enacted measures requiring all local school districts to follow uniform financial accounting and reporting standards (UFARS). Since 1980, the…

  17. School District Purchasing.

    ERIC Educational Resources Information Center

    Natale, Joseph L.

    This chapter of "Principles of School Business Management" discusses the effective management of purchasing processes in a school district. These processes include obtaining materials, supplies, and equipment of maximum value for the least expense, and receiving, storing, and distributing the items obtained. The chapter opens with an overview of…

  18. District-Level Downsizing

    ERIC Educational Resources Information Center

    Schachter, Ron

    2011-01-01

    Draconian cuts have become the order of business for many school districts since the economic recession hit in 2008. But for the coming school year, "draconian" has taken on an even harsher meaning, as states from California and Texas to Illinois and New York wrestle with deficits in the tens of billions of dollars and make multi-billion-dollar…

  19. Districts Shun Stimulus Bids

    ERIC Educational Resources Information Center

    Maxwell, Lesli A.

    2010-01-01

    In the final sprint to polish Race to the Top applications, hundreds of school districts shunned a shot at a share of $4 billion in grants by refusing to sign on to their states' plans for the federal competition. California officials had secured the signatures of 790 local education agencies (leas) late last week, including most of the state's…

  20. School District Budgeting.

    ERIC Educational Resources Information Center

    Hartman, William T.

    This book is devoted exclusively to the budgeting process in school districts, unlike the more common generic budgeting texts. As such, it allows an in-depth treatment of both conceptual and practical aspects of budgeting in a single volume. By default, school business officials have had to rely on the state education accounting manual as their…

  1. Districts Weigh Obesity Screening

    ERIC Educational Resources Information Center

    Butler, Kevin

    2008-01-01

    Parents of children in most elementary grades in Minnesota's Independent School District 191 receive an annual notice with potentially life-altering data for their children--and they are not state test scores, attendance rates, or grades. The notice contains the child's body mass index (BMI) score, which estimates whether the student has excess…

  2. District Consolidation: Rivals Coming Together

    ERIC Educational Resources Information Center

    Mart, Dan

    2011-01-01

    District consolidation is a highly emotional process. One key to success is sticking to the facts. In Iowa, school districts facing financial difficulties or enrollment concerns do not have to move directly to consolidation. In many cases, districts begin by developing sharing agreements. These sharing agreements may start with simple sharing of…

  3. USACE DIVISION AND DISTRICT BOUNDARIES

    EPA Science Inventory

    The USACE Division and District Boundary data contains the delination of Corps Division and District boundaries. District and Division Boundaries are based on the US political and watershed boundaries. In the mid 1990's, WES created the file by digitizing the 1984 Civil Wor...

  4. FACTORS IN FUTURE DISTRICT ORGANIZATION.

    ERIC Educational Resources Information Center

    Citrus Junior Coll., Azusa, CA.

    CALIFORNIA HAS ACCEPTED THE CONCEPT THAT ALL SCHOOL DISTRICTS ARE TO BE INCLUDED IN JUNIOR COLLEGE DISTRICTS. THIS STUDY DETERMINED WHAT EFFECT ANY CHANGE IN THE TERRITORY NOW INCLUDED IN THE CITRUS JUNIOR COLLEGE DISTRICT WOULD HAVE UPON THE SCHOOL'S ENROLLMENTS, BUILDING PROGRAM, AND FINANCIAL STRUCTURE. TOTAL ENROLLMENT IN THE COLLEGE, 1963-64,…

  5. A District's Journey to Inquiry

    ERIC Educational Resources Information Center

    Keeling, Mary

    2009-01-01

    Students learn best from well-designed instruction. To what extent can a school district design a curriculum that supports inquiry learning? How can a district implement consistent inquiry practices in forty schools? In this article, the author discusses Newport News Public School District's journey to inquiry which began in 2004 with a…

  6. Data center cooling system

    SciTech Connect

    Chainer, Timothy J; Dang, Hien P; Parida, Pritish R; Schultz, Mark D; Sharma, Arun

    2015-03-17

    A data center cooling system may include heat transfer equipment to cool a liquid coolant without vapor compression refrigeration, and the liquid coolant is used on a liquid cooled information technology equipment rack housed in the data center. The system may also include a controller-apparatus to regulate the liquid coolant flow to the liquid cooled information technology equipment rack through a range of liquid coolant flow values based upon information technology equipment temperature thresholds.

  7. Stochastic cooling in RHIC

    SciTech Connect

    Brennan,J.M.; Blaskiewicz, M. M.; Severino, F.

    2009-05-04

    After the success of longitudinal stochastic cooling of bunched heavy ion beam in RHIC, transverse stochastic cooling in the vertical plane of Yellow ring was installed and is being commissioned with proton beam. This report presents the status of the effort and gives an estimate, based on simulation, of the RHIC luminosity with stochastic cooling in all planes.

  8. Controlled Rate Cooling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Controlled-rate cooling is one of several techniques available for the long-term storage of plants in liquid nitrogen. In this technique samples are slowly cooled to an intermediate temperature and then plunged in liquid nitrogen. Controlled rate cooling is based on osmotic regulation of cell conte...

  9. The Cool Flames Experiment

    NASA Technical Reports Server (NTRS)

    Pearlman, Howard; Chapek, Richard; Neville, Donna; Sheredy, William; Wu, Ming-Shin; Tornabene, Robert

    2001-01-01

    A space-based experiment is currently under development to study diffusion-controlled, gas-phase, low temperature oxidation reactions, cool flames and auto-ignition in an unstirred, static reactor. At Earth's gravity (1g), natural convection due to self-heating during the course of slow reaction dominates diffusive transport and produces spatio-temporal variations in the thermal and thus species concentration profiles via the Arrhenius temperature dependence of the reaction rates. Natural convection is important in all terrestrial cool flame and auto-ignition studies, except for select low pressure, highly dilute (small temperature excess) studies in small vessels (i.e., small Rayleigh number). On Earth, natural convection occurs when the Rayleigh number (Ra) exceeds a critical value of approximately 600. Typical values of the Ra, associated with cool flames and auto-ignitions, range from 104-105 (or larger), a regime where both natural convection and conduction heat transport are important. When natural convection occurs, it alters the temperature, hydrodynamic, and species concentration fields, thus generating a multi-dimensional field that is extremely difficult, if not impossible, to be modeled analytically. This point has been emphasized recently by Kagan and co-workers who have shown that explosion limits can shift depending on the characteristic length scale associated with the natural convection. Moreover, natural convection in unstirred reactors is never "sufficiently strong to generate a spatially uniform temperature distribution throughout the reacting gas." Thus, an unstirred, nonisothermal reaction on Earth does not reduce to that generated in a mechanically, well-stirred system. Interestingly, however, thermal ignition theories and thermokinetic models neglect natural convection and assume a heat transfer correlation of the form: q=h(S/V)(T(bar) - Tw) where q is the heat loss per unit volume, h is the heat transfer coefficient, S/V is the surface to volume ratio, and (T(bar) - Tw ) is the spatially averaged temperature excess. This Newtonian form has been validated in spatially-uniform, well-stirred reactors, provided the effective heat transfer coefficient associated with the unsteady process is properly evaluated. Unfortunately, it is not a valid assumption for spatially-nonuniform temperature distributions induced by natural convection in unstirred reactors. "This is why the analysis of such a system is so difficult." Historically, the complexities associated with natural convection were perhaps recognized as early as 1938 when thermal ignition theory was first developed. In the 1955 text "Diffusion and Heat Exchange in Chemical Kinetics", Frank-Kamenetskii recognized that "the purely conductive theory can be applied at sufficiently low pressure and small dimensions of the vessel when the influence of natural convection can be disregarded." This was reiterated by Tyler in 1966 and further emphasized by Barnard and Harwood in 1974. Specifically, they state: "It is generally assumed that heat losses are purely conductive. While this may be valid for certain low pressure slow combustion regimes, it is unlikely to be true for the cool flame and ignition regimes." While this statement is true for terrestrial experiments, the purely conductive heat transport assumption is valid at microgravity (mu-g). Specifically, buoyant complexities are suppressed at mu-g and the reaction-diffusion structure associated with low temperature oxidation reactions, cool flames and auto-ignitions can be studied. Without natural convection, the system is simpler, does not require determination of the effective heat transfer coefficient, and is a testbed for analytic and numerical models that assume pure diffusive transport. In addition, mu-g experiments will provide baseline data that will improve our understanding of the effects of natural convection on Earth.

  10. Decentralization: The Administrator's Guidebook to School District Change.

    ERIC Educational Resources Information Center

    Brown, Daniel J.

    The school district decentralization process is described in this guidebook, which focuses on the administrator's role in implementation. Three chapters are organized around the three phases of decentralization--exploration, trial, and commitment. Each phase is examined in terms of the real-life experiences of administrators and other…

  11. 36 CFR 28.3 - Boundaries: The Community Development District; The Dune District; The Seashore District.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Boundaries: The Community Development District; The Dune District; The Seashore District. 28.3 Section 28.3 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR FIRE ISLAND NATIONAL SEASHORE: ZONING...

  12. 36 CFR 28.3 - Boundaries: The Community Development District; The Dune District; The Seashore District.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Boundaries: The Community Development District; The Dune District; The Seashore District. 28.3 Section 28.3 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR FIRE ISLAND NATIONAL SEASHORE: ZONING STANDARDS General Provisions § 28.3...

  13. Cooling water distribution system

    DOEpatents

    Orr, Richard

    1994-01-01

    A passive containment cooling system for a nuclear reactor containment vessel. Disclosed is a cooling water distribution system for introducing cooling water by gravity uniformly over the outer surface of a steel containment vessel using an interconnected series of radial guide elements, a plurality of circumferential collector elements and collector boxes to collect and feed the cooling water into distribution channels extending along the curved surface of the steel containment vessel. The cooling water is uniformly distributed over the curved surface by a plurality of weirs in the distribution channels.

  14. Elastic Metal Alloy Refrigerants: Thermoelastic Cooling

    SciTech Connect

    2010-10-01

    BEETIT Project: UMD is developing an energy-efficient cooling system that eliminates the need for synthetic refrigerants that harm the environment. More than 90% of the cooling and refrigeration systems in the U.S. today use vapor compression systems which rely on liquid to vapor phase transformation of synthetic refrigerants to absorb or release heat. Thermoelastic cooling systems, however, use a solid-state material—an elastic shape memory metal alloy—as a refrigerant and a solid to solid phase transformation to absorb or release heat. UMD is developing and testing shape memory alloys and a cooling device that alternately absorbs or creates heat in much the same way as a vapor compression system, but with significantly less energy and a smaller operational footprint.

  15. STOCHASTIC COOLING POWER REQUIREMENTS.

    SciTech Connect

    WEI,J.BLASKIEWICZ,M.BRENNAN,M.

    2004-07-05

    A practical obstacle for stochastic cooling in high-energy colliders like RHIC is the large amount of power needed for the cooling system. Based on the coasting-beam Fokker-Planck (F-P) equation, we analytically derived the optimum cooling rate and cooling power for a beam of uniform distribution and a cooling system of linear gain function. The results indicate that the usual back-of-envelope formula over-estimated the cooling power by a factor of the mixing factor M. On the other hand, the scaling laws derived from the coasting-beam Fokker-Planck approach agree with those derived from the bunched-beam Fokker-Planck approach if the peak beam intensity is used as the effective coasting-beam intensity. A longitudinal stochastic cooling system of 4-8 GHz bandwidth in RHIC can effectively counteract intrabeam scattering, preventing the beam from escaping the RF bucket becoming debunched around the ring.

  16. Potential Refrigerants for Power Electronics Cooling

    SciTech Connect

    Starke, M.R.

    2005-10-24

    In the past, automotive refrigerants have conventionally been used solely for the purpose of air conditioning. However, with the development of hybrid-electric vehicles and the incorporation of power electronics (PEs) into the automobile, automotive refrigerants are taking on a new role. Unfortunately, PEs have lifetimes and functionalities that are highly dependent on temperature and as a result thermal control plays an important role in the performance of PEs. Typically, PEs are placed in the engine compartment where the internal combustion engine (ICE) already produces substantial heat. Along with the ICE heat, the additional thermal energy produced by PEs themselves forces designers to use different cooling methods to prevent overheating. Generally, heat sinks and separate cooling loops are used to maintain the temperature. Disturbingly, the thermal control system can consume one third of the total volume and may weigh more than the PEs [1]. Hence, other avenues have been sought to cool PEs, including submerging PEs in automobile refrigerants to take advantage of two-phase cooling. The objective of this report is to explore the different automotive refrigerants presently available that could be used for PE cooling. Evaluation of the refrigerants will be done by comparing environmental effects and some thermo-physical properties important to two-phase cooling, specifically measuring the dielectric strengths of potential candidates. Results of this report will be used to assess the different candidates with good potential for future use in PE cooling.

  17. Evaporative cooling of the dipolar hydroxyl radical.

    PubMed

    Stuhl, Benjamin K; Hummon, Matthew T; Yeo, Mark; Qumner, Goulven; Bohn, John L; Ye, Jun

    2012-12-20

    Atomic physics was revolutionized by the development of forced evaporative cooling, which led directly to the observation of Bose-Einstein condensation, quantum-degenerate Fermi gases and ultracold optical lattice simulations of condensed-matter phenomena. More recently, substantial progress has been made in the production of cold molecular gases. Their permanent electric dipole moment is expected to generate systems with varied and controllable phases, dynamics and chemistry. However, although advances have been made in both direct cooling and cold-association techniques, evaporative cooling has not been achieved so far. This is due to unfavourable ratios of elastic to inelastic scattering and impractically slow thermalization rates in the available trapped species. Here we report the observation of microwave-forced evaporative cooling of neutral hydroxyl (OH()) molecules loaded from a Stark-decelerated beam into an extremely high-gradient magnetic quadrupole trap. We demonstrate cooling by at least one order of magnitude in temperature, and a corresponding increase in phase-space density by three orders of magnitude, limited only by the low-temperature sensitivity of our spectroscopic thermometry technique. With evaporative cooling and a sufficiently large initial population, much colder temperatures are possible; even a quantum-degenerate gas of this dipolar radical (or anything else it can sympathetically cool) may be within reach. PMID:23257881

  18. Cooling Scenario for the HESR Complex

    SciTech Connect

    Stockhorst, H.; Prasuhn, D.; Maier, R.; Lorentz, B.

    2006-03-20

    The High-Energy Storage Ring (HESR) of the future International Facility for Antiproton and Ion Research (FAIR) at GSI in Darmstadt is planned as an anti-proton cooler ring in the momentum range from 1.5 to 15 GeV/c. An important and challenging feature of the new facility is the combination of phase space cooled beams with internal targets. The required beam parameters and intensities are prepared in two operation modes: the high luminosity mode with beam intensities up to 1011 anti-protons, and the high resolution mode with 1010 anti-protons cooled down to a relative momentum spread of only a few 10-5. Consequently, powerful phase space cooling is needed, taking advantage of high-energy electron cooling and high-bandwidth stochastic cooling. Both cooling techniques are envisaged here theoretically, including the effect of beam-target interaction and intra-beam scattering to find especially for stochastic cooling the best system parameters.

  19. The MANX Muon Cooling Experiment Detection System

    NASA Astrophysics Data System (ADS)

    Kahn, S. A.; Abrams, R. J.; Ankenbrandt, C.; Cummings, M. A. C.; Johnson, R. P.; Robertsa, T. J.; Yoneharab, K.

    2010-03-01

    The MANX experiment is being proposed to demonstrate the reduction of 6D muon phase space emittance, using a continuous liquid absorber to provide ionization cooling in a helical solenoid magnetic channel. The experiment involves the construction of a two-period-long helical cooling channel (HCC) to reduce the muon invariant emittance by a factor of two. The HCC would replace the current cooling section of the MICE experiment now being set up at the Rutherford Appleton Laboratory. The MANX experiment would use the existing MICE spectrometers and muon beam line. We discuss the placement of detection planes to optimize the muon track resolution.

  20. Alabama district flood plan

    USGS Publications Warehouse

    Hedgecock, T. Scott; Pearman, J. Leroy; Stricklin, Victor E.

    2002-01-01

    The purpose of this flood plan is to outline and record advance planning for flood emergencies, so that all personnel will know the general plan and have a ready-reference for necessary information. This will ensure that during any flood event, regardless of the extent or magnitude, the resources of the District can be mobilized into a maximum data collection operation with a mimimum of effort.

  1. Stochastic cooling in RHIC

    SciTech Connect

    Brennan J. M.; Blaskiewicz, M.; Mernick, K.

    2012-05-20

    The full 6-dimensional [x,x'; y,y'; z,z'] stochastic cooling system for RHIC was completed and operational for the FY12 Uranium-Uranium collider run. Cooling enhances the integrated luminosity of the Uranium collisions by a factor of 5, primarily by reducing the transverse emittances but also by cooling in the longitudinal plane to preserve the bunch length. The components have been deployed incrementally over the past several runs, beginning with longitudinal cooling, then cooling in the vertical planes but multiplexed between the Yellow and Blue rings, next cooling both rings simultaneously in vertical (the horizontal plane was cooled by betatron coupling), and now simultaneous horizontal cooling has been commissioned. The system operated between 5 and 9 GHz and with 3 x 10{sup 8} Uranium ions per bunch and produces a cooling half-time of approximately 20 minutes. The ultimate emittance is determined by the balance between cooling and emittance growth from Intra-Beam Scattering. Specific details of the apparatus and mathematical techniques for calculating its performance have been published elsewhere. Here we report on: the method of operation, results with beam, and comparison of results to simulations.

  2. Axion cooling of neutron stars

    NASA Astrophysics Data System (ADS)

    Sedrakian, Armen

    2016-03-01

    Cooling simulations of neutron stars and their comparison with the data from thermally emitting x-ray sources put constraints on the properties of axions, and by extension, of any light pseudoscalar dark matter particles, whose existence has been postulated to solve the strong-C P problem of QCD. We incorporate the axion emission by pair-breaking and formation processes by S - and P -wave nucleonic condensates in a benchmark code for cooling simulations, as well as provide fit formulas for the rates of these processes. Axion cooling of neutron stars has been simulated for 24 models covering the mass range 1 to 1.8 solar masses, featuring nonaccreted iron and accreted light-element envelopes, and a range of nucleon-axion couplings. The models are based on an equation state predicting conservative physics of superdense nuclear matter that does not allow for the onset of fast cooling processes induced by phase transitions to non-nucleonic forms of matter or high proton concentration. The cooling tracks in the temperature vs age plane were confronted with the (time-averaged) measured surface temperature of the central compact object in the Cas A supernova remnant as well as surface temperatures of three nearby middle-aged thermally emitting pulsars. We find that the axion coupling is limited to fa/107 GeV ≥(5 - 10 ) , which translates into an upper bound on axion mass ma≤(0.06 - 0.12 ) eV for Peccei-Quinn charges of the neutron |Cn|˜0.04 and proton |Cp|˜0.4 characteristic for hadronic models of axions.

  3. Gas turbine cooling system

    DOEpatents

    Bancalari, Eduardo E.

    2001-01-01

    A gas turbine engine (10) having a closed-loop cooling circuit (39) for transferring heat from the hot turbine section (16) to the compressed air (24) produced by the compressor section (12). The closed-loop cooling system (39) includes a heat exchanger (40) disposed in the flow path of the compressed air (24) between the outlet of the compressor section (12) and the inlet of the combustor (14). A cooling fluid (50) may be driven by a pump (52) located outside of the engine casing (53) or a pump (54) mounted on the rotor shaft (17). The cooling circuit (39) may include an orifice (60) for causing the cooling fluid (50) to change from a liquid state to a gaseous state, thereby increasing the heat transfer capacity of the cooling circuit (39).

  4. RF Integration into Helical Magnet for Muon 6-Dimensional Beam Cooling

    SciTech Connect

    Yonehara, K.; Kashikhin, V.; Lamm, M.; Lee, A.; Lopes, M.; Zlobin, A.; Johnson, R.P.; Kahn, S.; Neubauer, M.; /Muons Inc., Batavia

    2009-05-01

    The helical cooling channel is proposed to make a quick muon beam phase space cooling in a short channel length. The challenging part of the helical cooling channel magnet design is how to integrate the RF cavity into the compact helical cooling magnet. This report shows the possibility of the integration of the system.

  5. Power electronics cooling apparatus

    SciTech Connect

    Sanger, P.A.; Lindberg, F.A.; Garcen, W.

    2000-01-18

    A semiconductor cooling arrangement wherein a semiconductor is affixed to a thermally and electrically conducting carrier such as by brazing. The coefficient of thermal expansion of the semiconductor and carrier are closely matched to one another so that during operation they will not be overstressed mechanically due to thermal cycling. Electrical connection is made to the semiconductor and carrier, and a porous metal heat exchanger is thermally connected to the carrier. The heat exchanger is positioned within an electrically insulating cooling assembly having cooling oil flowing therethrough. The arrangement is particularly well adapted for the cooling of high power switching elements in a power bridge.

  6. Power electronics cooling apparatus

    SciTech Connect

    Sanger, Philip Albert; Lindberg, Frank A.; Garcen, Walter

    2000-01-01

    A semiconductor cooling arrangement wherein a semiconductor is affixed to a thermally and electrically conducting carrier such as by brazing. The coefficient of thermal expansion of the semiconductor and carrier are closely matched to one another so that during operation they will not be overstressed mechanically due to thermal cycling. Electrical connection is made to the semiconductor and carrier, and a porous metal heat exchanger is thermally connected to the carrier. The heat exchanger is positioned within an electrically insulating cooling assembly having cooling oil flowing therethrough. The arrangement is particularly well adapted for the cooling of high power switching elements in a power bridge.

  7. Semioptimal practicable algorithmic cooling

    SciTech Connect

    Elias, Yuval; Mor, Tal; Weinstein, Yossi

    2011-04-15

    Algorithmic cooling (AC) of spins applies entropy manipulation algorithms in open spin systems in order to cool spins far beyond Shannon's entropy bound. Algorithmic cooling of nuclear spins was demonstrated experimentally and may contribute to nuclear magnetic resonance spectroscopy. Several cooling algorithms were suggested in recent years, including practicable algorithmic cooling (PAC) and exhaustive AC. Practicable algorithms have simple implementations, yet their level of cooling is far from optimal; exhaustive algorithms, on the other hand, cool much better, and some even reach (asymptotically) an optimal level of cooling, but they are not practicable. We introduce here semioptimal practicable AC (SOPAC), wherein a few cycles (typically two to six) are performed at each recursive level. Two classes of SOPAC algorithms are proposed and analyzed. Both attain cooling levels significantly better than PAC and are much more efficient than the exhaustive algorithms. These algorithms are shown to bridge the gap between PAC and exhaustive AC. In addition, we calculated the number of spins required by SOPAC in order to purify qubits for quantum computation. As few as 12 and 7 spins are required (in an ideal scenario) to yield a mildly pure spin (60% polarized) from initial polarizations of 1% and 10%, respectively. In the latter case, about five more spins are sufficient to produce a highly pure spin (99.99% polarized), which could be relevant for fault-tolerant quantum computing.

  8. Passive containment cooling system

    DOEpatents

    Conway, Lawrence E.; Stewart, William A.

    1991-01-01

    A containment cooling system utilizes a naturally induced air flow and a gravity flow of water over the containment shell which encloses a reactor core to cool reactor core decay heat in two stages. When core decay heat is greatest, the water and air flow combine to provide adequate evaporative cooling as heat from within the containment is transferred to the water flowing over the same. The water is heated by heat transfer and then evaporated and removed by the air flow. After an initial period of about three to four days when core decay heat is greatest, air flow alone is sufficient to cool the containment.

  9. Raman cooling of atoms in an optical dipole trap

    SciTech Connect

    Lee, H.J.; Adams, C.S.; Kasevich, M.; Chu, S.

    1996-04-01

    We have Raman cooled sodium atoms below the photon recoil temperature in a novel type of blue-detuned optical dipole force trap. In this trap 4.5{times}10{sup 5} atoms have been cooled to an effective three dimensional temperature of 1.0 {mu}K at a final density of 4{times}10{sup 11} cm{sup {minus}3}. No atoms were lost during the cooling process. The phase space density increased by a factor of 320 over the uncooled sample. This is the highest phase space density achieved by an all-optical cooling method. {copyright} {ital 1996 The American Physical Society.}

  10. Impact of Cooling Rate on the Durability of PHA Glasses

    SciTech Connect

    Edwards, T.B.

    2001-06-04

    This study was conducted to determine the effect, if any, on the PCT responses of glasses cooled at different rates. Two bounding cooling profiles were used in this study: rapidly quenched and a canister centerline cooling curve. Glasses were selected based on a number of criteria, but mainly to challenge the regions where amorphous phase separation is expected based upon current model predictions. The current DWPF homogeneity constraint, imposed to preclude regions of phase separation, predicted that most of the glasses selected would be phase separated. It was, therefore, important to ensure that deleterious phase separation does not occur at either cooling profile. In this case, deleterious phase separation is defined as the formation of an amorphous phase in the glass that significantly decreases the glass durability as measured by the PCT response.

  11. Analysis of County School Districts in Arkansas.

    ERIC Educational Resources Information Center

    Budd, Karol B.; Charlton, J.L.

    The 1948, Arkansas School District Reorganization Act was passed in an effort to reduce the 1589 small school districts to a smaller number. Those districts not consolidated would form county districts. As of the 1967-68 school year, 26 of these county districts remained. The purpose of this study was to provide information drawing attention to…

  12. Suburban District Leaders' Perception of Their Practices

    ERIC Educational Resources Information Center

    Garcia France, Roxanne

    2013-01-01

    In the field of district leadership, most studies focus only on the context and conditions existing in large urban districts in need of reform. This study examined whether district leadership practices have applicability to district leaders working within the suburban context. In addition, it determined whether district conditions (i.e., district…

  13. Stacking with stochastic cooling

    NASA Astrophysics Data System (ADS)

    Caspers, Fritz; Möhl, Dieter

    2004-10-01

    Accumulation of large stacks of antiprotons or ions with the aid of stochastic cooling is more delicate than cooling a constant intensity beam. Basically the difficulty stems from the fact that the optimized gain and the cooling rate are inversely proportional to the number of particles 'seen' by the cooling system. Therefore, to maintain fast stacking, the newly injected batch has to be strongly 'protected' from the Schottky noise of the stack. Vice versa the stack has to be efficiently 'shielded' against the high gain cooling system for the injected beam. In the antiproton accumulators with stacking ratios up to 105 the problem is solved by radial separation of the injection and the stack orbits in a region of large dispersion. An array of several tapered cooling systems with a matched gain profile provides a continuous particle flux towards the high-density stack core. Shielding of the different systems from each other is obtained both through the spatial separation and via the revolution frequencies (filters). In the 'old AA', where the antiproton collection and stacking was done in one single ring, the injected beam was further shielded during cooling by means of a movable shutter. The complexity of these systems is very high. For more modest stacking ratios, one might use azimuthal rather than radial separation of stack and injected beam. Schematically half of the circumference would be used to accept and cool new beam and the remainder to house the stack. Fast gating is then required between the high gain cooling of the injected beam and the low gain stack cooling. RF-gymnastics are used to merge the pre-cooled batch with the stack, to re-create free space for the next injection, and to capture the new batch. This scheme is less demanding for the storage ring lattice, but at the expense of some reduction in stacking rate. The talk reviews the 'radial' separation schemes and also gives some considerations to the 'azimuthal' schemes.

  14. Liquid metal cooled nuclear reactors with passive cooling system

    DOEpatents

    Hunsbedt, Anstein; Fanning, Alan W.

    1991-01-01

    A liquid metal cooled nuclear reactor having a passive cooling system for removing residual heat resulting from fuel decay during reactor shutdown. The passive cooling system comprises a plurality of cooling medium flow circuits which cooperate to remove and carry heat away from the fuel core upon loss of the normal cooling flow circuit to areas external thereto.

  15. Saint Paul Energy Park: the potential for district heating

    SciTech Connect

    Lee, C.; Kron, R.; Davis, H.

    1980-03-01

    The results of ANL's study of the energy and economic aspects of using district heating in the St. Paul Energy Park are summarized. The Energy Park is a 6 million ft/sup 2/ residential, commercial office, and light industrial complex to be built in the midway area of St. Paul, Minnesota. Space heating and cooling design loads for the park were calculated assuming that the ASHRAE's 90-75 energy-conserving construction standards would be used in constructing the park's buildings. Based in part on this assumption, ANL estimated the costs and energy use characteristics of six possible energy system options for supplying Energy Park's space heating, space cooling, and domestic hot water heating needs. The results indicate that in today's economy, a central heating and cooling plant with natural gas boilers and electrically driven centrifugal chillers with thermal storage has good potential for energy and economic savings and clearly merits further consideration.

  16. DOAS, Radiant Cooling Revisited

    SciTech Connect

    Hastbacka, Mildred; Dieckmann, John; Bouza, Antonio

    2012-12-01

    The article discusses dedicated outdoor air systems (DOAS) and radiant cooling technologies. Both of these topics were covered in previous ASHRAE Journal columns. This article reviews the technologies and their increasing acceptance. The two steps that ASHRAE is taking to disseminate DOAS information to the design community, available energy savings and the market potential of radiant cooling systems are addressed as well.

  17. Measure Guideline: Ventilation Cooling

    SciTech Connect

    Springer, D.; Dakin, B.; German, A.

    2012-04-01

    The purpose of this measure guideline on ventilation cooling is to provide information on a cost-effective solution for reducing cooling system energy and demand in homes located in hot-dry and cold-dry climates. This guideline provides a prescriptive approach that outlines qualification criteria, selection considerations, and design and installation procedures.

  18. Coherent electron cooling

    SciTech Connect

    Litvinenko,V.

    2009-05-04

    Cooling intense high-energy hadron beams remains a major challenge in modern accelerator physics. Synchrotron radiation is still too feeble, while the efficiency of two other cooling methods, stochastic and electron, falls rapidly either at high bunch intensities (i.e. stochastic of protons) or at high energies (e-cooling). In this talk a specific scheme of a unique cooling technique, Coherent Electron Cooling, will be discussed. The idea of coherent electron cooling using electron beam instabilities was suggested by Derbenev in the early 1980s, but the scheme presented in this talk, with cooling times under an hour for 7 TeV protons in the LHC, would be possible only with present-day accelerator technology. This talk will discuss the principles and the main limitations of the Coherent Electron Cooling process. The talk will describe the main system components, based on a high-gain free electron laser driven by an energy recovery linac, and will present some numerical examples for ions and protons in RHIC and the LHC and for electron-hadron options for these colliders. BNL plans a demonstration of the idea in the near future.

  19. Cool Earth Solar

    ScienceCinema

    Lamkin, Rob; McIlroy, Andy; Swalwell, Eric; Rajan, Kish

    2014-02-26

    In a public-private partnership that takes full advantage of the Livermore Valley Open Campus (LVOC) for the first time, Sandia National Laboratories and Cool Earth Solar have signed an agreement that could make solar energy more affordable and accessible. In this piece, representatives from Sandia, Cool Earth Solar, and leaders in California government all discuss the unique partnership and its expected impact.

  20. Data center cooling method

    DOEpatents

    Chainer, Timothy J.; Dang, Hien P.; Parida, Pritish R.; Schultz, Mark D.; Sharma, Arun

    2015-08-11

    A method aspect for removing heat from a data center may use liquid coolant cooled without vapor compression refrigeration on a liquid cooled information technology equipment rack. The method may also include regulating liquid coolant flow to the data center through a range of liquid coolant flow values with a controller-apparatus based upon information technology equipment temperature threshold of the data center.

  1. Why Cool Roofs?

    ScienceCinema

    Chu, Steven

    2013-05-29

    By installing a cool roof at DOE, the federal government and Secretary Chu are helping to educate families and businesses about the important energy and cost savings that can come with this simple, low-cost technology. Cool roofs have the potential to quickly and dramatically reduce global carbon emissions while saving money every month on consumers' electrical bills.

  2. Why Cool Roofs?

    SciTech Connect

    Chu, Steven

    2010-01-01

    By installing a cool roof at DOE, the federal government and Secretary Chu are helping to educate families and businesses about the important energy and cost savings that can come with this simple, low-cost technology. Cool roofs have the potential to quickly and dramatically reduce global carbon emissions while saving money every month on consumers' electrical bills.

  3. S'COOL Science

    ERIC Educational Resources Information Center

    Bryson, Linda

    2004-01-01

    This article describes one fifth grade's participation in in NASA's S'COOL (Students' Cloud Observations On-Line) Project, making cloud observations, reporting them online, exploring weather concepts, and gleaning some of the things involved in authentic scientific research. S?COOL is part of a real scientific study of the effect of clouds on…

  4. Cool Earth Solar

    SciTech Connect

    Lamkin, Rob; McIlroy, Andy; Swalwell, Eric; Rajan, Kish

    2013-04-22

    In a public-private partnership that takes full advantage of the Livermore Valley Open Campus (LVOC) for the first time, Sandia National Laboratories and Cool Earth Solar have signed an agreement that could make solar energy more affordable and accessible. In this piece, representatives from Sandia, Cool Earth Solar, and leaders in California government all discuss the unique partnership and its expected impact.

  5. S'COOL Science

    ERIC Educational Resources Information Center

    Bryson, Linda

    2004-01-01

    This article describes one fifth grade's participation in in NASA's S'COOL (Students' Cloud Observations On-Line) Project, making cloud observations, reporting them online, exploring weather concepts, and gleaning some of the things involved in authentic scientific research. S?COOL is part of a real scientific study of the effect of clouds on

  6. District Support of School Improvement: Highlights from Three Districts. Newsletter

    ERIC Educational Resources Information Center

    Center for Comprehensive School Reform and Improvement, 2009

    2009-01-01

    This newsletter addresses various supports that districts are utilizing to help keep students in school and on the path to graduation. Described herein are three districts that have been particularly successful in raising student achievement--even though they differ in their specific strategies, fund allocation, and demographic composition. A…

  7. Turbine blade cooling

    DOEpatents

    Staub, Fred Wolf; Willett, Fred Thomas

    1999-07-20

    A turbine rotor blade comprises a shank portion, a tip portion and an airfoil. The airfoil has a pressure side wall and a suction side wall that are interconnected by a plurality of partition sidewalls, defining an internal cooling passageway within the airfoil. The internal cooling passageway includes at least one radial outflow passageway to direct a cooling medium flow from the shank portion towards the tip portion and at least one radial inflow passageway to direct a cooling medium flow from the tip portion towards the shank portion. A number of mixing ribs are disposed on the partition sidewalls within the radial outflow passageways so as to enhance the thermal mixing of the cooling medium flow, thereby producing improved heat transfer over a broad range of the Buoyancy number.

  8. Turbine blade cooling

    DOEpatents

    Staub, Fred Wolf; Willett, Fred Thomas

    2000-01-01

    A turbine rotor blade comprises a shank portion, a tip portion and an airfoil. The airfoil has a pressure side wall and a suction side wall that are interconnected by a plurality of partition sidewalls, defining an internal cooling passageway within the airfoil. The internal cooling passageway includes at least one radial outflow passageway to direct a cooling medium flow from the shank portion towards the tip portion and at least one radial inflow passageway to direct a cooling medium flow from the tip portion towards the shank portion. A number of mixing ribs are disposed on the partition sidewalls within the radial outflow passageways so as to enhance the thermal mixing of the cooling medium flow, thereby producing improved heat transfer over a broad range of the Buoyancy number.

  9. Hydronic rooftop cooling systems

    DOEpatents

    Bourne, Richard C.; Lee, Brian Eric; Berman, Mark J.

    2008-01-29

    A roof top cooling unit has an evaporative cooling section that includes at least one evaporative module that pre-cools ventilation air and water; a condenser; a water reservoir and pump that captures and re-circulates water within the evaporative modules; a fan that exhausts air from the building and the evaporative modules and systems that refill and drain the water reservoir. The cooling unit also has a refrigerant section that includes a compressor, an expansion device, evaporator and condenser heat exchangers, and connecting refrigerant piping. Supply air components include a blower, an air filter, a cooling and/or heating coil to condition air for supply to the building, and optional dampers that, in designs that supply less than 100% outdoor air to the building, control the mixture of return and ventilation air.

  10. Turbine blade cooling

    DOEpatents

    Staub, F.W.; Willett, F.T.

    1999-07-20

    A turbine rotor blade comprises a shank portion, a tip portion and an airfoil. The airfoil has a pressure side wall and a suction side wall that are interconnected by a plurality of partition sidewalls, defining an internal cooling passageway within the airfoil. The internal cooling passageway includes at least one radial outflow passageway to direct a cooling medium flow from the shank portion towards the tip portion and at least one radial inflow passageway to direct a cooling medium flow from the tip portion towards the shank portion. A number of mixing ribs are disposed on the partition sidewalls within the radial outflow passageways so as to enhance the thermal mixing of the cooling medium flow, thereby producing improved heat transfer over a broad range of the Buoyancy number. 13 figs.

  11. Water cooled steam jet

    DOEpatents

    Wagner, Jr., Edward P.

    1999-01-01

    A water cooled steam jet for transferring fluid and preventing vapor lock, or vaporization of the fluid being transferred, has a venturi nozzle and a cooling jacket. The venturi nozzle produces a high velocity flow which creates a vacuum to draw fluid from a source of fluid. The venturi nozzle has a converging section connected to a source of steam, a diffuser section attached to an outlet and a throat portion disposed therebetween. The cooling jacket surrounds the venturi nozzle and a suction tube through which the fluid is being drawn into the venturi nozzle. Coolant flows through the cooling jacket. The cooling jacket dissipates heat generated by the venturi nozzle to prevent vapor lock.

  12. Water cooled steam jet

    DOEpatents

    Wagner, E.P. Jr.

    1999-01-12

    A water cooled steam jet for transferring fluid and preventing vapor lock, or vaporization of the fluid being transferred, has a venturi nozzle and a cooling jacket. The venturi nozzle produces a high velocity flow which creates a vacuum to draw fluid from a source of fluid. The venturi nozzle has a converging section connected to a source of steam, a diffuser section attached to an outlet and a throat portion disposed there between. The cooling jacket surrounds the venturi nozzle and a suction tube through which the fluid is being drawn into the venturi nozzle. Coolant flows through the cooling jacket. The cooling jacket dissipates heat generated by the venturi nozzle to prevent vapor lock. 2 figs.

  13. Prospects of laser cooling in atomic thallium

    SciTech Connect

    Fan, Isaac; Chen, Tzu-Ling; Liu, Yu-Sheng; Lien, Yu-Hung; Liu, Yi-Wei; Shy, Jow-Tsong

    2011-10-15

    One of the most precisely determined upper limits for the electron electric dipole moment (EDM) is set by the thallium (Tl) atomic beam experiment. One way to enhance the sensitivity of the atomic beam setup is to laser cool the Tl atoms to reduce the EDM-like phase caused by the Exv effect. In this report, a cooling scheme based on the 6P{sub 3/2}(F=2){r_reversible}6D{sub 5/2}(F{sup '}=3) transition in Tl is proposed. The absolute frequency measurement of this nearly closed-cycle transition was performed in an atomic beam apparatus. Two Ti:sapphire lasers were frequency-doubled using enhancement cavities in X-type configurations to provide the needed 377- and 352-nm light sources for the optical pumping and cooling transitions, respectively. The absolute frequency of this cooling transition is determined to be 851 634 646(56) MHz.

  14. The Phoenix Cluster: A Bonafide Cooling Flow?

    NASA Astrophysics Data System (ADS)

    McDonald, Michael

    2014-11-01

    The Phoenix Cluster (SPT-CLJ2344-4243), the most X-ray luminous cluster yet discovered, is host to a massive cooling flow which appears to be fueling an extreme starburst in the central galaxy. Unlike the vast majority of clusters discovered to date, Phoenix appears to be fulfilling early cooling flow predictions, converting a substantial fraction of the cooling intracluster gas into stars (~800 Msun/yr). This runaway cooling phase appears to be short lived, and it remains unclear what triggered it and why it hasn't been observed in a larger fraction of nearby clusters. We will discuss the discovery of this system along with recent follow-up observations aimed at explaining its extreme nature, including recently-obtained deep UV and X-ray spectroscopy of the cluster core.

  15. Computer Applications Planning. A Guide to Planning and Implementing a District-Wide Computer Program.

    ERIC Educational Resources Information Center

    Mojkowski, Charles

    Designed to help school districts move from exploring the use of computers in the classroom to the comprehensive planning and development of computer education programs, this guide is organized around five steps essential to the process of developing a district program. Phase 1 includes the following preliminary activities involved in planning for…

  16. A Demographic Analysis of the Impact of Property Tax Caps on Indiana School Districts

    ERIC Educational Resources Information Center

    Hirth, Marilyn A.; Lagoni, Christopher

    2014-01-01

    In 2008, the Indiana legislature passed and the governor signed into law House Enrolled Act No. 1001, now referred to as Public Law 146-2008, which capped Indiana school districts' ability to raise revenues from the local property tax without local voter approval. To phase in the impact of the law, the state provided school districts with…

  17. Progress Report: The Development of a School District Budget Planning System (SPLAN). A Technical Memorandum.

    ERIC Educational Resources Information Center

    Bratten, J. E.; And Others

    The design and initial trial phase of a project to develop a computer-based budget planning system for school districts are reported in this document. From a teletype at the district office linked to a computer at System Development Corporation, a user (administrator) can retrieve specific portions or summaries of a prestored description of his…

  18. RHIC stochastic cooling motion control

    SciTech Connect

    Gassner, D.; DeSanto, L.; Olsen, R.H.; Fu, W.; Brennan, J.M.; Liaw, CJ; Bellavia, S.; Brodowski, J.

    2011-03-28

    Relativistic Heavy Ion Collider (RHIC) beams are subject to Intra-Beam Scattering (IBS) that causes an emittance growth in all three-phase space planes. The only way to increase integrated luminosity is to counteract IBS with cooling during RHIC stores. A stochastic cooling system for this purpose has been developed, it includes moveable pick-ups and kickers in the collider that require precise motion control mechanics, drives and controllers. Since these moving parts can limit the beam path aperture, accuracy and reliability is important. Servo, stepper, and DC motors are used to provide actuation solutions for position control. The choice of motion stage, drive motor type, and controls are based on needs defined by the variety of mechanical specifications, the unique performance requirements, and the special needs required for remote operations in an accelerator environment. In this report we will describe the remote motion control related beam line hardware, position transducers, rack electronics, and software developed for the RHIC stochastic cooling pick-ups and kickers.

  19. 7 CFR 946.31 - Districts.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... included in either the Quincy or South Irrigation Districts which lies east of township vertical line R27E... Irrigation Districts which lies west of township line R28E. (c) District No. 3—The counties of...

  20. Cooled-Spool Piston Compressor

    NASA Technical Reports Server (NTRS)

    Morris, Brian G.

    1994-01-01

    Proposed cooled-spool piston compressor driven by hydraulic power and features internal cooling of piston by flowing hydraulic fluid to limit temperature of compressed gas. Provides sufficient cooling for higher compression ratios or reactive gases. Unlike conventional piston compressors, all parts of compressed gas lie at all times within relatively short distance of cooled surface so that gas cooled more effectively.

  1. Internal Auditing for School Districts.

    ERIC Educational Resources Information Center

    Cuzzetto, Charles

    This book provides guidelines for conducting internal audits of school districts. The first five chapters provide an overview of internal auditing and describe techniques that can be used to improve or implement internal audits in school districts. They offer information on the definition and benefits of internal auditing, the role of internal…

  2. Suburban District Leadership Does Matter

    ERIC Educational Resources Information Center

    Thompson, Eustace; France, Roxanne Garcia

    2015-01-01

    The increased demand for educational reform and accountability has resulted in a renewed focus on the relationship between building leaders and district leaders, particularly on how district leaders can support principals to ensure the academic success of students. The No Child Left Behind Act of 2001 (NCLB) and Race to the Top (RttT) legislations…

  3. Redesigning the District Operating System

    ERIC Educational Resources Information Center

    Hodas, Steven

    2015-01-01

    In this paper, we look at the inner workings of a school district through the lens of the "district operating system (DOS)," a set of interlocking mutually-reinforcing modules that includes functions like procurement, contracting, data and IT policy, the general counsel's office, human resources, and the systems for employee and family…

  4. Districts' Efficiency Evaluated in Report

    ERIC Educational Resources Information Center

    Samuels, Christina A.

    2011-01-01

    A report from a progressive think tank measuring the "educational productivity" of more than 9,000 school districts around the country says that districts getting the most for their money tend to spend more on teachers and less on administration, partner with their communities to save money, and have school boards willing to make potentially

  5. Congressional Districting: A Historical Overview.

    ERIC Educational Resources Information Center

    Baran, Jan Witold; Cronic, Jason P.

    1996-01-01

    Examines the controversies and consequences involved in drawing proper districts for federal and state representatives. Discusses the Supreme Court's role in deciding these questions. Provides definitions and related court cases concerning gerrymandering and malapportionment, the two most common abuses of the districting process. (MJP)

  6. Presumptions against School District Secession

    ERIC Educational Resources Information Center

    Murray, Dale

    2009-01-01

    While political philosophers have paid a great deal of attention to providing a theory of secession for cases of nations breaking away from nation-states, little has been said about perhaps the most common type of secession--school district secession. I argue that while there is no principled prohibition against school district secession, there

  7. Districts' Efficiency Evaluated in Report

    ERIC Educational Resources Information Center

    Samuels, Christina A.

    2011-01-01

    A report from a progressive think tank measuring the "educational productivity" of more than 9,000 school districts around the country says that districts getting the most for their money tend to spend more on teachers and less on administration, partner with their communities to save money, and have school boards willing to make potentially…

  8. Advanced energy transmission fluids for heating and cooling systems

    SciTech Connect

    Kasza, K.E.; Choi, S.U.; Kaminsky, J.

    1987-06-01

    The U.S. Department of Energy (DOE) is sponsoring a comprehensive program to develop high-performance energy transmission fluids for use in district heating and cooling (DHC) systems. These fluids would substantially reduce flow frictional losses and enhance heat transfer. In system enhancement scoping studies, the fluids have been shown to yield potentially significant upfront capital equipment cost reductions by allowing the use of smaller pipes, pumps, heat exchangers, and storage tanks as well as reductions in operational costs.

  9. MEIC electron cooling program

    SciTech Connect

    Derbenev, Yaroslav S.; Zhang, Yuhong

    2014-12-01

    Cooling of proton and ion beams is essential for achieving high luminosities (up to above 1034 cm-2s-1) for MEIC, a Medium energy Electron-Ion Collider envisioned at JLab [1] for advanced nuclear science research. In the present conceptual design, we utilize the conventional election cooling method and adopted a multi-staged cooling scheme for reduction of and maintaining low beam emittances [2,3,4]. Two electron cooling facilities are required to support the scheme: one is a low energy (up to 2 MeV) DC cooler installed in the MEIC ion pre-booster (with the proton kinetic energy up to 3 GeV); the other is a high electron energy (up to 55 MeV) cooler in the collider ring (with the proton kinetic energy from 25 to 100 GeV). The high energy cooler, which is based on the ERL technology and a circulator ring, utilizes a bunched electron beam to cool bunched proton or ion beams. To complete the MEIC cooling concept and a technical design of the ERL cooler as well as to develop supporting technologies, an R&D program has been initiated at Jefferson Lab and significant progresses have been made since then. In this study, we present a brief description of the cooler design and a summary of the progress in this cooling R&D.

  10. MEIC electron cooling program

    DOE PAGESBeta

    Derbenev, Yaroslav S.; Zhang, Yuhong

    2014-12-01

    Cooling of proton and ion beams is essential for achieving high luminosities (up to above 1034 cm-2s-1) for MEIC, a Medium energy Electron-Ion Collider envisioned at JLab [1] for advanced nuclear science research. In the present conceptual design, we utilize the conventional election cooling method and adopted a multi-staged cooling scheme for reduction of and maintaining low beam emittances [2,3,4]. Two electron cooling facilities are required to support the scheme: one is a low energy (up to 2 MeV) DC cooler installed in the MEIC ion pre-booster (with the proton kinetic energy up to 3 GeV); the other is amore » high electron energy (up to 55 MeV) cooler in the collider ring (with the proton kinetic energy from 25 to 100 GeV). The high energy cooler, which is based on the ERL technology and a circulator ring, utilizes a bunched electron beam to cool bunched proton or ion beams. To complete the MEIC cooling concept and a technical design of the ERL cooler as well as to develop supporting technologies, an R&D program has been initiated at Jefferson Lab and significant progresses have been made since then. In this study, we present a brief description of the cooler design and a summary of the progress in this cooling R&D.« less

  11. Optoelectrical Cooling of Polar Molecules to Submillikelvin Temperatures

    NASA Astrophysics Data System (ADS)

    Prehn, Alexander; Ibrügger, Martin; Glöckner, Rosa; Rempe, Gerhard; Zeppenfeld, Martin

    2016-02-01

    We demonstrate direct cooling of gaseous formaldehyde (H2 CO ) to the microkelvin regime. Our approach, optoelectrical Sisyphus cooling, provides a simple dissipative cooling method applicable to electrically trapped dipolar molecules. By reducing the temperature by 3 orders of magnitude and increasing the phase-space density by a factor of ˜104, we generate an ensemble of 3 ×105 molecules with a temperature of about 420 μ K , populating a single rotational state with more than 80% purity.

  12. Optoelectrical Cooling of Polar Molecules to Submillikelvin Temperatures.

    PubMed

    Prehn, Alexander; Ibrgger, Martin; Glckner, Rosa; Rempe, Gerhard; Zeppenfeld, Martin

    2016-02-12

    We demonstrate direct cooling of gaseous formaldehyde (H_{2}CO) to the microkelvin regime. Our approach, optoelectrical Sisyphus cooling, provides a simple dissipative cooling method applicable to electrically trapped dipolar molecules. By reducing the temperature by 3 orders of magnitude and increasing the phase-space density by a factor of ?10^{4}, we generate an ensemble of 310^{5} molecules with a temperature of about 420???K, populating a single rotational state with more than 80% purity. PMID:26918988

  13. Analytical investigation of chord size and cooling methods on turbine blade cooling requirements. Book 1: Sections 1 through 8 and appendixes A through I

    NASA Technical Reports Server (NTRS)

    Faulkner, F. E.

    1971-01-01

    A study was conducted to determine the effect of chord size on air cooled turbine blades. In the preliminary design phase, eight turbine blade cooling configurations in 0.75-in., 1.0-in., and 1.5-in. chord sizes were analyzed to determine the maximum turbine inlet temperature capabilities. A pin fin convection cooled configuration and a film-impingement cooled configuration were selected for a final design analysis in which the maximum turbine inlet temperature was determined as a function of the cooling air inlet temperature and the turbine inlet total pressure for each of the three chord sizes. The cooling air flow requirements were also determined for a varying cooling air inlet temperature with a constant turbine inlet temperature. It was determined that allowable turbine inlet temperature increases with increasing chord for the convection cooled and transpiration cooled designs, however, the film-convection cooled designs did not have a significant change in turbine inlet temperature with chord.

  14. Personal Cooling System

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Cool Head, a personal cooling system for use in heat stress occupations, is a spinoff of a channeled cooling garment for space wear. It is portable and includes a heat exchanger, control display unit, liquid reservoir and temperature control unit. The user can eliminate 40 to 60 percent of his body's heat storage and lower heart rate by 50 to 80 beats a minute. The system is used by the Army, Navy, crop dusting pilots, heavy equipment operators and auto racing drivers and is marketed by Life Enhancement Technologies, LLC. Further applications are under consideration.

  15. Fermilab Recycler Stochastic Cooling for Luminosity Production

    SciTech Connect

    Broemmelsiek, D.; Gattuso, C.

    2006-03-20

    The Fermilab Recycler began regularly delivering antiprotons for Tevatron luminosity operations in 2005. Methods for tuning the Recycler stochastic cooling system are presented. The unique conditions and resulting procedures for minimizing the longitudinal phase space density of the Recycler antiproton beam are outlined.

  16. Supporting cancer patients with palliative care needs: district nurses' role perceptions.

    PubMed

    Griffiths, Jane; Ewing, Gail; Rogers, Margaret; Barclay, Stephen; Martin, Anna; McCabe, Janet; Todd, Chris

    2007-01-01

    The aim of this study was to examine UK district nurses' perceptions of their role in supporting palliative care cancer patients. Patients with cancer are living longer with the disease. District nurses are the largest UK workforce caring for people with cancer at home, the preferred place of care. Meeting patients' supportive and palliative care needs is complex. Little is known about district nurses' supportive role in the early phase of palliative care. Semistructured interviews were conducted with 34 district nurses. Data were analyzed thematically, with assistance from Atlas/ti. A dominant theme emerging from the interviews was ambiguity in the district nurses' supportive role in early palliative care. District nurses discussed the importance of making contact early on to support cancer patients and their families but had difficulty articulating this "support." Ambiguity, lack of confidence, and perceived skill deficits presented district nurses with dilemmas that were difficult to resolve. District nurses have great potential for meeting cancer patients' supportive and palliative care needs, a potential not currently realized. Education alone is unlikely to improve practice without an understanding of the tensions faced by district nurses in their work. Recognizing and addressing dilemmas in the everyday work of district nurses is central to moving practice forward. PMID:17413782

  17. District-heating strategy model: computer programmer's manual

    SciTech Connect

    Kuzanek, J.F.

    1982-05-01

    The US Department of Housing and Urban Development (HUD) and the US Department of Energy (DOE) cosponsor a program aimed at increasing the number of district heating and cooling (DHC) systems. Such systems can reduce the amount and costs of fuels used to heat and cool buildings in a district. Twenty-eight communities have agreed to aid HUD in a national feasibility assessment of DHC systems. The HUD/DOE program entails technical assistance by Argonne National Laboratory and Oak Ridge National Laboratory. The assistance includes a computer program, called the district heating strategy model (DHSM), that performs preliminary calculations to analyze potential DHC systems. This report describes the general capabilities of the DHSM, provides historical background on its development, and explains the computer installation and operation of the model - including the data file structures and the options. Sample problems illustrate the structure of the various input data files, the interactive computer-output listings. The report is written primarily for computer programmers responsible for installing the model on their computer systems, entering data, running the model, and implementing local modifications to the code.

  18. Cooling of solar flares plasmas. 1: Theoretical considerations

    NASA Technical Reports Server (NTRS)

    Cargill, Peter J.; Mariska, John T.; Antiochos, Spiro K.

    1995-01-01

    Theoretical models of the cooling of flare plasma are reexamined. By assuming that the cooling occurs in two separate phase where conduction and radiation, respectively, dominate, a simple analytic formula for the cooling time of a flare plasma is derived. Unlike earlier order-of-magnitude scalings, this result accounts for the effect of the evolution of the loop plasma parameters on the cooling time. When the conductive cooling leads to an 'evaporation' of chromospheric material, the cooling time scales L(exp 5/6)/p(exp 1/6), where the coronal phase (defined as the time maximum temperature). When the conductive cooling is static, the cooling time scales as L(exp 3/4)n(exp 1/4). In deriving these results, use was made of an important scaling law (T proportional to n(exp 2)) during the radiative cooling phase that was forst noted in one-dimensional hydrodynamic numerical simulations (Serio et al. 1991; Jakimiec et al. 1992). Our own simulations show that this result is restricted to approximately the radiative loss function of Rosner, Tucker, & Vaiana (1978). for different radiative loss functions, other scaling result, with T and n scaling almost linearly when the radiative loss falls off as T(exp -2). It is shown that these scaling laws are part of a class of analytic solutions developed by Antiocos (1980).

  19. Multilayer composite material and method for evaporative cooling

    NASA Technical Reports Server (NTRS)

    Buckley, Theresa M. (Inventor)

    2002-01-01

    A multilayer composite material and method for evaporative cooling of a person employs an evaporative cooling liquid that changes phase from a liquid to a gaseous state to absorb thermal energy. The evaporative cooling liquid is absorbed into a superabsorbent material enclosed within the multilayer composite material. The multilayer composite material has a high percentage of the evaporative cooling liquid in the matrix. The cooling effect can be sustained for an extended period of time because of the high percentage of phase change liquid that can be absorbed into the superabsorbent. Such a composite can be used for cooling febrile patients by evaporative cooling as the evaporative cooling liquid in the matrix changes from a liquid to a gaseous state to absorb thermal energy. The composite can be made with a perforated barrier material around the outside to regulate the evaporation rate of the phase change liquid. Alternatively, the composite can be made with an imperveous barrier material or semipermeable membrane on one side to prevent the liquid from contacting the person's skin. The evaporative cooling liquid in the matrix can be recharged by soaking the material in the liquid. The multilayer composite material can be fashioned into blankets, garments and other articles.

  20. District Computer Concerns: Checklist for Monitoring Instructional Use of Computers.

    ERIC Educational Resources Information Center

    Coe, Merilyn

    Designed to assist those involved with planning, organizing, and implementing computer use in schools, this checklist can be applied to: (1) assess the present state of instructional computer use in the district; (2) assist with the development of plans or guidelines for computer use; (3) support a start-up phase; and (4) monitor the…

  1. PPBS: Focus on Output Performance. One Local District.

    ERIC Educational Resources Information Center

    Scamman, James

    This document describes efforts to develop a planning-programing-budgeting system in a Kenosha, Wisconsin, school district of medium size. The PPBS is to be implemented in two phases: (1) an experimental program-oriented budget for the 1970-1971 school year, and (2) a 5-year plan to reevaluate and develop a program structure and program goals for…

  2. Dilemmas Presented by State Agency Takeovers of Local School Districts.

    ERIC Educational Resources Information Center

    Steffy, Betty E.

    During the 1988-89 school year, two local school districts were placed into "Phase III" of the Kentucky Educational Improvement Act (1978), a category of state receivership in which much local decision-making power was transferred to Kentucky Department of Education officials. When state education department intervention occurs, major issues arise…

  3. Dilemmas Presented by State Agency Takeovers of Local School Districts.

    ERIC Educational Resources Information Center

    Steffy, Betty E.

    During the 1988-89 school year, two local school districts were placed into "Phase III" of the Kentucky Educational Improvement Act (1978), a category of state receivership in which much local decision-making power was transferred to Kentucky Department of Education officials. When state education department intervention occurs, major issues arise

  4. Sperm Membrane Behaviour during Cooling and Cryopreservation.

    PubMed

    Sieme, H; Oldenhof, H; Wolkers, W F

    2015-09-01

    Native sperm is only marginally stable after collection. Cryopreservation of semen facilitates transport and storage for later use in artificial reproduction technologies, but cryopreservation processing may result in cellular damage compromising sperm function. Membranes are thought to be the primary site of cryopreservation injury. Therefore, insights into the effects of cooling, ice formation and protective agents on sperm membranes may help to rationally design cryopreservation protocols. In this review, we describe membrane phase behaviour of sperm at supra- and subzero temperatures. In addition, factors affecting membrane phase transitions and stability, sperm osmotic tolerance limits and mode of action of cryoprotective agents are discussed. It is shown how cooling only results in minor thermotropic non-cooperative phase transitions, whereas freezing causes sharp lyotropic fluid-to-gel phase transitions. Membrane cholesterol content affects suprazero membrane phase behaviour and osmotic tolerance. The rate and extent of cellular dehydration coinciding with freezing-induced membrane phase transitions are affected by the cooling rate and ice nucleation temperature and can be modulated by cryoprotective agents. Permeating agents such as glycerol can move across cellular membranes, whereas non-permeating agents such as sucrose cannot. Both, permeating and non-permeating protectants preserve biomolecular and cellular structures by forming a protective glassy state during freezing. PMID:26382025

  5. Sisyphus cooling of lithium

    NASA Astrophysics Data System (ADS)

    Hamilton, Paul; Kim, Geena; Joshi, Trinity; Mukherjee, Biswaroop; Tiarks, Daniel; Mller, Holger

    2014-02-01

    Laser cooling to sub-Doppler temperatures by optical molasses is thought to be inhibited in atoms with unresolved, near-degenerate hyperfine structure in the excited state. We demonstrate that such cooling is possible in one to three dimensions, not only near the standard D2 line for laser cooling, but over a wide range extending to the D1 line. Via a combination of Sisyphus cooling followed by adiabatic expansion, we reach temperatures as low as 40 ?K, which corresponds to atomic velocities a factor of 2.6 above the limit imposed by a single-photon recoil. Our method requires modest laser power at a frequency within reach of standard frequency-locking methods. It is largely insensitive to laser power, polarization and detuning, magnetic fields, and initial hyperfine populations. Our results suggest that optical molasses should be possible with all alkali-metal species.

  6. Evaporative Cooling Membrane Device

    NASA Technical Reports Server (NTRS)

    Lomax, Curtis (Inventor); Moskito, John (Inventor)

    1999-01-01

    An evaporative cooling membrane device is disclosed having a flat or pleated plate housing with an enclosed bottom and an exposed top that is covered with at least one sheet of hydrophobic porous material having a thin thickness so as to serve as a membrane. The hydrophobic porous material has pores with predetermined dimensions so as to resist any fluid in its liquid state from passing therethrough but to allow passage of the fluid in its vapor state, thereby, causing the evaporation of the fluid and the cooling of the remaining fluid. The fluid has a predetermined flow rate. The evaporative cooling membrane device has a channel which is sized in cooperation with the predetermined flow rate of the fluid so as to produce laminar flow therein. The evaporative cooling membrane device provides for the convenient control of the evaporation rates of the circulating fluid by adjusting the flow rates of the laminar flowing fluid.

  7. Waveguide cooling system

    NASA Technical Reports Server (NTRS)

    Chen, B. C. J.; Hartop, R. W. (Inventor)

    1981-01-01

    An improved system is described for cooling high power waveguides by the use of cooling ducts extending along the waveguide, which minimizes hot spots at the flanges where waveguide sections are connected together. The cooling duct extends along substantially the full length of the waveguide section, and each flange at the end of the section has a through hole with an inner end connected to the duct and an opposite end that can be aligned with a flange hole in another waveguide section. Earth flange is formed with a drainage groove in its face, between the through hole and the waveguide conduit to prevent leakage of cooling fluid into the waveguide. The ducts have narrowed sections immediately adjacent to the flanges to provide room for the installation of fasteners closely around the waveguide channel.

  8. Why Exercise Is Cool

    MedlinePlus

    ... put you in a better mood. When you exercise, your brain releases chemicals called endorphins (say: en-DOR-finz), which may make you feel happier. It's just another reason why exercise is cool! Reviewed by: Mary L. Gavin, MD ...

  9. Warm and Cool Dinosaurs.

    ERIC Educational Resources Information Center

    Mannlein, Sally

    2001-01-01

    Presents an art activity in which first grade students draw dinosaurs in order to learn about the concept of warm and cool colors. Explains how the activity also helped the students learn about the concept of distance when drawing. (CMK)

  10. Too cool to work

    NASA Astrophysics Data System (ADS)

    Moya, Xavier; Defay, Emmanuel; Heine, Volker; Mathur, Neil D.

    2015-03-01

    Magnetocaloric and electrocaloric effects are driven by doing work, but this work has barely been explored, even though these caloric effects are being exploited in a growing number of prototype cooling devices.

  11. Cooling of dense stars

    NASA Technical Reports Server (NTRS)

    Tsuruta, S.

    1972-01-01

    Cooling rates were calculated for neutron stars of about one solar mass and 10 km radius, with magnetic fields from zero to about 10 to the 14th power gauss, for extreme cases of maximum and zero superfluidity. The results show that most pulsars are so cold that thermal ionization of surface atoms would be negligible. Nucleon superfluidity and crystallization of heavy nuclei were treated quantitatively, and more realistic hadron star models were chosen. Cooling rates were calculated for a stable hyperon star near the maximum mass limit, a medium weight neutron star, and a light neutron star with neutron-rich heavy nuclei near the minimum mass limit. Results show that cooling rates are a sensitive function of density. The Crab and Vela pulsars are considered, as well as cooling of a massive white dwarf star.

  12. Implementation of Stochastic Cooling Hardware at Fermilab's Tevatron Collider

    SciTech Connect

    Pasquinelli, Ralph J.; /Fermilab

    2011-08-01

    The invention of Stochastic cooling by Simon van der Meer made possible the increase in phase space density of charged particle beams. In particular, this feedback technique allowed the development of proton antiproton colliders at both CERN and Fermilab. This paper describes the development of hardware systems necessary to cool antiprotons at the Fermilab Tevatron Collider complex.

  13. A possible ionization cooling experiment at the AGS

    SciTech Connect

    Fernow, R.C.; Gallardo, J.C.; Palmer, R.B.; Winn, D.R.; Neuffer, D.V.

    1996-01-01

    Ionization cooling may play an important role in reducing the phase space volume of muons for a future muon-muon collider. We describe possible transverse and longitudinal emittance cooling experiments that utilize the capabilities of the AGS at Brookhaven National Laboratory. {copyright} {ital 1995 American Institute of Physics.}

  14. A possible ionization cooling experiment at the AGS

    SciTech Connect

    Fernow, R.C.; Gallardo, J.C.; Palmer, R.B.; Winn, D.R.; Neuffer, D.V.

    1995-03-01

    Ionization cooling may play an important role in reducing the phase space density of muons for a future muon-muon collider. The authors describe possible transverse and longitudinal emittance cooling experiments that utilize the capabilities of the AGS at Brookhaven National Laboratory.

  15. Laser cooling of solids

    SciTech Connect

    Epstein, Richard I; Sheik-bahae, Mansoor

    2008-01-01

    We present an overview of solid-state optical refrigeration also known as laser cooling in solids by fluorescence upconversion. The idea of cooling a solid-state optical material by simply shining a laser beam onto it may sound counter intuitive but is rapidly becoming a promising technology for future cryocooler. We chart the evolution of this science in rare-earth doped solids and semiconductors.

  16. Refrigerant directly cooled capacitors

    DOEpatents

    Hsu, John S.; Seiber, Larry E.; Marlino, Laura D.; Ayers, Curtis W.

    2007-09-11

    The invention is a direct contact refrigerant cooling system using a refrigerant floating loop having a refrigerant and refrigeration devices. The cooling system has at least one hermetic container disposed in the refrigerant floating loop. The hermetic container has at least one electronic component selected from the group consisting of capacitors, power electronic switches and gating signal module. The refrigerant is in direct contact with the electronic component.

  17. Liquid cooled helmet

    NASA Technical Reports Server (NTRS)

    Elkins, William (Inventor); Williams, Bill A. (Inventor)

    1979-01-01

    Liquid cooled helmet comprising a cap of flexible material adapted to fit the head of a person, cooling panels mounted inside the cap forming passageways for carrying a liquid coolant, the panels being positioned to engage the cranium and neck of a person wearing the helmet, inlet and outlet lines communicating with the passageways, and releasable straps for securing the helmet about the neck of the wearer.

  18. WATER COOLED RETORT COVER

    DOEpatents

    Ash, W.J.; Pozzi, J.F.

    1962-05-01

    A retort cover is designed for use in the production of magnesium metal by the condensation of vaporized metal on a collecting surface. The cover includes a condensing surface, insulating means adjacent to the condensing surface, ind a water-cooled means for the insulating means. The irrangement of insulation and the cooling means permits the magnesium to be condensed at a high temperature and in massive nonpyrophoric form. (AEC)

  19. Cooling tower waste reduction

    SciTech Connect

    Coleman, S.J.; Celeste, J.; Chine, R.; Scott, C.

    1998-05-01

    At Lawrence Livermore National Laboratory (LLNL), the two main cooling tower systems (central and northwest) were upgraded during the summer of 1997 to reduce the generation of hazardous waste. In 1996, these two tower systems generated approximately 135,400 lbs (61,400 kg) of hazardous sludge, which is more than 90 percent of the hazardous waste for the site annually. At both, wet decks (cascade reservoirs) were covered to block sunlight. Covering the cascade reservoirs reduced the amount of chemical conditioners (e.g. algaecide and biocide), required and in turn the amount of waste generated was reduced. Additionally, at the northwest cooling tower system, a sand filtration system was installed to allow cyclical filtering and backflushing, and new pumps, piping, and spray nozzles were installed to increase agitation. the appurtenance upgrade increased the efficiency of the cooling towers. The sand filtration system at the northwest cooling tower system enables operators to continuously maintain the cooling tower water quality without taking the towers out of service. Operational costs (including waste handling and disposal) and maintenance activities are compared for the cooling towers before and after upgrades. Additionally, the effectiveness of the sand filter system in conjunction with the wet deck covers (northwest cooling tower system), versus the cascade reservoir covers alone (south cooling tower south) is discussed. the overall expected return on investment is calculated to be in excess of 250 percent. this upgrade has been incorporated into the 1998 DOE complex-wide water conservation project being led by Sandia National Laboratory/Albuquerque.

  20. SUMMARY OF BEAM COOLING AND INTRABEAM SCATTERING.

    SciTech Connect

    FEDOTOV, A.V.; MESHKOV, I.N.; WEI, J.

    2006-05-26

    For heavy-particle beams in storage rings where there is no significant synchrotron radiation damping, beam cooling is an essential tool in obtaining high phase-space density high brightness beams. Advances in various types of cooling such as electron, stochastic, laser and muon cooling are covered in dedicated Conferences. In this series of Workshops (HB2002-06), discussions are aimed only at a few specific subjects which are crucial for future projects. The discussion topics in our session closely followed those discussed during the HB2004 workshop [1]. Specifically, we concentrated on the topics of electron cooling and intrabeam scattering, motivated by the design of the future high-energy coolers [2,3,4]. These cooling projects at high-energy require accurate numerical modeling and experimental verification. A variety of tasks were put together at HB2004 [1]. In our working group we discussed a progress in addressing these tasks. We had 10 presentations [5]-[14] (with additional presentations in the joint sessions) which followed by dedicated discussions. Our main topics of discussions: intrabeam scattering (IBS), electron cooling, and beam stability are summarized.

  1. Metallographic Cooling Rate of IVA Irons Revisited

    NASA Technical Reports Server (NTRS)

    Yang, J.; Goldstein, J. I.; Scott, E. R. D.

    2005-01-01

    There is long standing problem reconciling the chemical evidence that the IVA iron meteorites formed in a core with the diverse cooling rates reported by several researchers. This large inferred range of cooling rates suggests that the IVA irons were distributed at different depths in a parent body with a complex structure when the Widmanstatten pattern formed. On the other hand, some researchers argued that the diverse cooling rates in group IVA result from inaccurate model parameters such as phase diagram, interdiffusion coefficients, and kamacite nucleation and growth mechanisms. In addition, the measured cooling rates may not apply for the same cooling temperature ranges, and the variation in the crystallographic orientations of the Widmanstatten plates on the analysis surface may result in inaccurate measurements of widths needed for the computer simulation models. We have revaluated the major parameters in computer model developed by Hopfe and Goldstein and measured cooling rates for the IVA irons. Such data are useful in evaluating whether these meteorites were part of a single core of a parent body during the formation of the Widmanstatten pattern.

  2. Advanced cooling techniques for FASTBUS electronics

    SciTech Connect

    Chato, J.C.; Golliher, E.L.; Downing, R.W.

    1986-02-01

    A multi-phase research and development effort has been conducted to explore improved cooling techniques for the FASTBUS system. The research was supported by the Fermi National Accelerator Laboratory. Some of the relevant, major requirements and limits of this system are: 1. The cooling system should not significantly interfere with the rapid handling of the cards; 2. The die temperatures of the integrated circuits should not exceed 85/sup 0/C; 3. The temperature differential between the dies of emitter coupled logic (ECL) circuits that connect directly to each other should not exceed 30/sup 0/C; 4. The temperature differential of the cooling air between any two points in the module should not exceed 20/sup 0/C; 5. In air cooled modules, the air temperature should not exceed 60/sup 0/C anywhere; and 6. The noise emanating from the computer should be at a tolerable level. The first requirement, together with some related considerations, virtually excludes any direct liquid cooling schemes. Thus heat removal from the chips themselves can be achieved either by convection to air or by a heat conducting structure which transfers the heat to the coolant used. The second through fourth requirements are generally rigorous. However, the fifth is for plastic encased microchips (CA3083 16-pin, high current transistor, dual in-line package) and can be relaxed for other types with lower internal thermal resistances. Our work can be divided into three parts. The first dealt with the development of an air cooled system based on the state-of-the-art of commercially available technology. The second explored various air cooling techniques and the third, examined methods where the heat from the chips was conducted to water cooled plates located parallel to the chip carrying cards.

  3. 25 CFR 81.9 - Voting districts.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Voting districts. 81.9 Section 81.9 Indians BUREAU OF... STATUTE § 81.9 Voting districts. If: (a) Voting districts have not already been designated for tribal... board's judgment voting districts are needed, the board shall establish them and designate a...

  4. 25 CFR 81.9 - Voting districts.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Voting districts. 81.9 Section 81.9 Indians BUREAU OF... STATUTE § 81.9 Voting districts. If: (a) Voting districts have not already been designated for tribal... board's judgment voting districts are needed, the board shall establish them and designate a...

  5. 25 CFR 81.9 - Voting districts.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Voting districts. 81.9 Section 81.9 Indians BUREAU OF... STATUTE § 81.9 Voting districts. If: (a) Voting districts have not already been designated for tribal... board's judgment voting districts are needed, the board shall establish them and designate a...

  6. 25 CFR 81.9 - Voting districts.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Voting districts. 81.9 Section 81.9 Indians BUREAU OF... STATUTE § 81.9 Voting districts. If: (a) Voting districts have not already been designated for tribal... board's judgment voting districts are needed, the board shall establish them and designate a...

  7. 25 CFR 81.9 - Voting districts.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Voting districts. 81.9 Section 81.9 Indians BUREAU OF... STATUTE § 81.9 Voting districts. If: (a) Voting districts have not already been designated for tribal... board's judgment voting districts are needed, the board shall establish them and designate a...

  8. 7 CFR 906.20 - Districts.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... are hereby initially established: District No. 1: The county of Cameron in the State of Texas; District No. 2: The county of Hidalgo in the State of Texas; and District No. 3 The county of Willacy in... RIO GRANDE VALLEY IN TEXAS Order Regulating Handling Committee § 906.20 Districts. For the purpose...

  9. 7 CFR 906.20 - Districts.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... are hereby initially established: District No. 1: The county of Cameron in the State of Texas; District No. 2: The county of Hidalgo in the State of Texas; and District No. 3 The county of Willacy in... RIO GRANDE VALLEY IN TEXAS Order Regulating Handling Committee § 906.20 Districts. For the purpose...

  10. 7 CFR 906.20 - Districts.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... are hereby initially established: District No. 1: The county of Cameron in the State of Texas; District No. 2: The county of Hidalgo in the State of Texas; and District No. 3 The county of Willacy in... RIO GRANDE VALLEY IN TEXAS Order Regulating Handling Committee § 906.20 Districts. For the purpose...

  11. 7 CFR 906.20 - Districts.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... are hereby initially established: District No. 1: The county of Cameron in the State of Texas; District No. 2: The county of Hidalgo in the State of Texas; and District No. 3 The county of Willacy in... RIO GRANDE VALLEY IN TEXAS Order Regulating Handling Committee § 906.20 Districts. For the purpose...

  12. Electron cooling rates characterization at Fermilab's Recycler

    SciTech Connect

    Prost, Lionel R.; Shemyakin, A.; /Fermilab

    2007-06-01

    A 0.1 A, 4.3 MeV DC electron beam is routinely used to cool 8 GeV antiprotons in Fermilab's Recycler storage ring [1]. The primary function of the electron cooler is to increase the longitudinal phase-space density of the antiprotons for storing and preparing high-density bunches for injection into the Tevatron. The longitudinal cooling rate is found to significantly depend on the transverse emittance of the antiproton beam. The paper presents the measured rates and compares them with calculations based on drag force data.

  13. On radiational cooling computations in clouds.

    NASA Technical Reports Server (NTRS)

    Knollenberg, R. G.

    1972-01-01

    Expressions are derived for the cooling or heating rates for clouds in which the condensed phase is either ice or water. Values are computed for ice and water clouds over a reasonable temperature range for pressures of 1000, 500, and 200 mb. The importance is shown of adequately allowing for the latent load in computations of radiative cooling or heating rates based on measurements of radiative divergence in clouds. It is shown that, other things being equal, the effect of the latent load is always greatest at low levels and higher temperatures.

  14. Cool WISPs for stellar cooling excesses

    NASA Astrophysics Data System (ADS)

    Giannotti, Maurizio; Irastorza, Igor; Redondo, Javier; Ringwald, Andreas

    2016-05-01

    Several stellar systems (white dwarfs, red giants, horizontal branch stars and possibly the neutron star in the supernova remnant Cassiopeia A) show a mild preference for a non-standard cooling mechanism when compared with theoretical models. This exotic cooling could be provided by Weakly Interacting Slim Particles (WISPs), produced in the hot cores and abandoning the star unimpeded, contributing directly to the energy loss. Taken individually, these excesses do not show a strong statistical weight. However, if one mechanism could consistently explain several of them, the hint could be significant. We analyze the hints in terms of neutrino anomalous magnetic moments, minicharged particles, hidden photons and axion-like particles (ALPs). Among them, the ALP or a massless HP represent the best solution. Interestingly, the hinted ALP parameter space is accessible to the next generation proposed ALP searches, such as ALPS II and IAXO and the massless HP requires a multi TeV energy scale of new physics that might be accessible at the LHC.

  15. Boise geothermal district heating system

    SciTech Connect

    Hanson, P.J.

    1985-10-01

    This document describes the Boise geothermal district heating project from preliminary feasibility studies completed in 1979 to a fully operational system by 1983. The report includes information about the two local governments that participated in the project - the City of Boise, Idaho and the Boise Warm Springs Water District. It also discusses the federal funding sources; the financial studies; the feasibility studies conducted; the general system planning and design; design of detailed system components; the legal issues involved in production; geological analysis of the resource area; distribution and disposal; the program to market system services; and the methods of retrofitting buildings to use geothermal hot water for space heating. Technically this report describes the Boise City district heating system based on 170/sup 0/F water, a 4000 gpm production system, a 41,000 foot pipeline system, and system economies. Comparable data are also provided for the Boise Warm Springs Water District. 62 figs., 31 tabs.

  16. District heating campaign in Sweden

    SciTech Connect

    Stalebrant, R.E.

    1995-09-01

    During the fall of 1994 a district heating campaign was conducted in Sweden. The campaign was initiated because the Swedish district heating companies agreed that it was time to increase knowledge and awareness of district heating among the general public, especially among potential customers. The campaign involved many district heating companies and was organized as a special project. Advertising companies, media advisers, consultants and investigators were also engaged. The campaign was conducted in two stages, a national campaign followed by local campaign was conducted in two stages, a national campaign followed by local campaigns. The national campaign was conducted during two weeks of November 1994 and comprised advertising on commercial TV and in the press.

  17. 33 CFR 1.01-50 - Delegation to District Commander, Seventeenth Coast Guard District.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., Seventeenth Coast Guard District. 1.01-50 Section 1.01-50 Navigation and Navigable Waters COAST GUARD... District Commander, Seventeenth Coast Guard District. The Commandant redelegates to the District Commander, Seventeenth Coast Guard District, the authority in 46 U.S.C. 3302(i)(1) to issue permits to certain...

  18. 33 CFR 1.01-50 - Delegation to District Commander, Seventeenth Coast Guard District.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., Seventeenth Coast Guard District. 1.01-50 Section 1.01-50 Navigation and Navigable Waters COAST GUARD... District Commander, Seventeenth Coast Guard District. The Commandant redelegates to the District Commander, Seventeenth Coast Guard District, the authority in 46 U.S.C. 3302(i)(1) to issue permits to certain...

  19. 33 CFR 1.01-50 - Delegation to District Commander, Seventeenth Coast Guard District.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., Seventeenth Coast Guard District. 1.01-50 Section 1.01-50 Navigation and Navigable Waters COAST GUARD... District Commander, Seventeenth Coast Guard District. The Commandant redelegates to the District Commander, Seventeenth Coast Guard District, the authority in 46 U.S.C. 3302(i)(1) to issue permits to certain...

  20. 33 CFR 1.01-50 - Delegation to District Commander, Seventeenth Coast Guard District.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., Seventeenth Coast Guard District. 1.01-50 Section 1.01-50 Navigation and Navigable Waters COAST GUARD... District Commander, Seventeenth Coast Guard District. The Commandant redelegates to the District Commander, Seventeenth Coast Guard District, the authority in 46 U.S.C. 3302(i)(1) to issue permits to certain...

  1. High-temperature turbine-technology program. Phase II. Technology test and support studies. Topical report. Development of an analytical method to describe and predict particulate deposition on transpiration-air-cooled turbine blades

    SciTech Connect

    Not Available

    1982-07-01

    This report presents an introduction to the subject of deposition in gas turbines operating on coal-derived fuels. Included are a literature review, examination of the role of electrophoresis on deposition and experimental results of deposition studies conducted in the gas turbine environment. The experimental studies are related to the charge on hot gases (contaminated and non-contaminated) passing through a turbine and deposition measurements on charged, uncharged, transpiration-air-cooled, water-cooled, and uncooled test samples. It is shown that the electrical charge on hot turbine gases is proportional to the quadratic of fluid-particle velocity and directly proportional to particle concentration. The ionic concentration of the gas turbine medium increases with the increase in temperature in the range of 1000/sup 0/F to 2000/sup 0/F. The deposition was found to be less for the transpiration-air-cooled test sample (approx. 1300/sup 0/F) and the excessively water-cooled test sample (approx. 350/sup 0/F) than for the uncooled and uncharged test samples. It was also found that, by using the electrostatic means, a potential exists for a reduction in deposition on gas turbine blades operating in a particulate-laden medium.

  2. Design and development of LH2 cooled rolling element radial bearings for the NERVA engine turbopump. Volume 3: Phase 2: Tests on build-ups 16, 17, and 18 at NRDS, Jackass Flats, Nevada, December 1971 - March 1972

    NASA Technical Reports Server (NTRS)

    Accinelli, J. B.; Koch, D. A.; Reuter, F.

    1972-01-01

    The use of liquid hydrogen to cool the rolling element radial bearings in the nuclear engine for rocket vehicles is discussed. The fifteen hour service life goal was obtained during the tests. The increase in bearing life was also considered to be produced by: (1) improvements in bearing material, (2) bearing retainer configuration and manufacturing changes, and (3) better control of operating parameters.

  3. Research Proposal for the Design and Engineering Phase of a Solar Heating and Cooling System Experiment at the Warner Robins Public Library, Warner Robins, Georgia. Submitted to the United States Energy Research and Development Administration.

    ERIC Educational Resources Information Center

    Phillips, Warren H.; And Others

    A number of reasons are advanced to include a solar heating and cooling experiment in a library building. The unique aspects of the experiment are to be a seasonally adjustable collector tilt and testing of a new generation of absorption air conditioners. After a brief description of the proposed experiment, the proposal contains forms filed by…

  4. PERFORMANCE ANALYSIS OF MECHANICAL DRAFT COOLING TOWER

    SciTech Connect

    Lee, S; Alfred Garrett, A; James02 Bollinger, J; Larry Koffman, L

    2009-02-10

    Industrial processes use mechanical draft cooling towers (MDCT's) to dissipate waste heat by transferring heat from water to air via evaporative cooling, which causes air humidification. The Savannah River Site (SRS) has cross-flow and counter-current MDCT's consisting of four independent compartments called cells. Each cell has its own fan to help maximize heat transfer between ambient air and circulated water. The primary objective of the work is to simulate the cooling tower performance for the counter-current cooling tower and to conduct a parametric study under different fan speeds and ambient air conditions. The Savannah River National Laboratory (SRNL) developed a computational fluid dynamics (CFD) model and performed the benchmarking analysis against the integral measurement results to accomplish the objective. The model uses three-dimensional steady-state momentum, continuity equations, air-vapor species balance equation, and two-equation turbulence as the basic governing equations. It was assumed that vapor phase is always transported by the continuous air phase with no slip velocity. In this case, water droplet component was considered as discrete phase for the interfacial heat and mass transfer via Lagrangian approach. Thus, the air-vapor mixture model with discrete water droplet phase is used for the analysis. A series of parametric calculations was performed to investigate the impact of wind speeds and ambient conditions on the thermal performance of the cooling tower when fans were operating and when they were turned off. The model was also benchmarked against the literature data and the SRS integral test results for key parameters such as air temperature and humidity at the tower exit and water temperature for given ambient conditions. Detailed results will be published here.

  5. Ruocco's immunocompromised cutaneous district.

    PubMed

    Piccolo, Vincenzo; Baroni, Adone; Russo, Teresa; Schwartz, Robert A

    2016-02-01

    The concept of 'locus minoris resistentiae' (lmr) is an old but still effective way of thinking in Medicine. In Dermatology, there are many reports of privileged localization of cutaneous diseases on injured skin, which therefore represents a typical condition of lmr. Lately the innovative concept of immunocompromised cutaneous district (ICD) has been introduced to explain why a previously injured cutaneous site may become in time a privileged location for the outbreak of opportunistic infections, tumors, and immune reactions. An ample documentation of multifarious disorders (infectious, neoplastic, immune) appearing in ICDs was delineated by Ruocco et al. in 2009. These cases were grouped according to the clinical settings responsible for the local immune imbalance: regional chronic lymphedema; herpes-infected sites, which feature the well-known Wolf's isotopic response; and otherwise damaged areas, comprising sites of vaccination, ionizing or UV radiation, thermal burns, and traumas. In the following five years, what was a "novel" pathogenic concept has been extended to an enlarging variety of clinical conditions. This paper focuses on ICD and the expanding spectrum of this now established pathogenic concept. PMID:26475059

  6. Spray Cooling Modeling: Droplet Sub-Cooling Effect on Heat Transfer

    SciTech Connect

    Johnston, Joseph E.; Selvam, R. P.; Silk, Eric A.

    2008-01-21

    Spray cooling has become increasingly popular as a thermal management solution for high-heat flux (>100 W/cm{sup 2}) applications such as laser diodes and radars. Research has shown that using sub-cooled liquid can increase the heat flux from the hot surface. The objective of this study was to use a multi-phase numerical model to simulate the effect of a sub-cooled droplet impacting a growing vapor bubble in a thin (<100 {mu}m) liquid film. The two-phase model captured the liquid-vapor interface using the level set method. The effects of surface tension, viscosity, gravity and phase change were accounted for by using a modification to the incompressible Navier-Stokes equations, which were solved using the finite difference method. The computed liquid-vapor interface and temperature distributions were visualized for better understanding of the heat removal process. To understand the heat transfer mechanisms of sub-cooled droplet impact on a growing vapor bubble, various initial droplet temperatures were modeled (from 20 deg. C below saturation temperature to saturation temperature). This may provide insights into how to improve the heat transfer in future spray cooling systems.

  7. STOCHASTIC COOLING FOR RHIC.

    SciTech Connect

    BLASKIEWICZ,M.BRENNAN,J.M.CAMERON,P.WEI,J.

    2003-05-12

    Emittance growth due to Intra-Beam Scattering significantly reduces the heavy ion luminosity lifetime in RHIC. Stochastic cooling of the stored beam could improve things considerably by counteracting IBS and preventing particles from escaping the rf bucket [1]. High frequency bunched-beam stochastic cooling is especially challenging but observations of Schottky signals in the 4-8 GHz band indicate that conditions are favorable in RHIC [2]. We report here on measurements of the longitudinal beam transfer function carried out with a pickup kicker pair on loan from FNAL TEVATRON. Results imply that for ions a coasting beam description is applicable and we outline some general features of a viable momentum cooling system for RHIC.

  8. Passive containment cooling system

    SciTech Connect

    Billig, Paul F.; Cooke, Franklin E.; Fitch, James R.

    1994-01-01

    A passive containment cooling system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and a gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel and is vented to the drywell. An isolation pool is disposed above the GDCS pool and includes an isolation condenser therein. The condenser has an inlet line disposed in flow communication with the drywell for receiving the non-condensable gas along with any steam released therein following a loss-of-coolant accident (LOCA). The condenser also has an outlet line disposed in flow communication with the drywell for returning to the drywell both liquid condensate produced upon cooling of the steam and the non-condensable gas for reducing pressure within the containment vessel following the LOCA.

  9. Three dimensional projection cooling

    NASA Astrophysics Data System (ADS)

    Li, Xiao; Nelson, Karl D.; Deb, Amita B.; Weiss, David S.

    2010-03-01

    We have significantly improved the laser cooling of single atoms trapped in a 3D optical lattice with 5 μm spacing. We use microwaves to drive lower sideband transitions between two spin states, whose spatial wavefunctions are temporarily displaced by a small lattice polarization rotation. Subsequent optical pumping completes a cooling cycle in one dimension, similar to Raman sideband cooling, but without the Raman beams [1]. We perform this cycle for each spatial direction, and repeat the process 30 times. The final vibrational excitation is below 0.2hν in each direction, despite the Lamb-Dicke parameter being a relatively high η = 0.37. We will also discuss our progress on performing arbitrary single qubit rotations on a target atom without affecting its neighbors. These are both important elements in the development of a site-addressable neutral atom quantum computer. [4pt] [1] Leonid Forster, et al PRL 103, 233001 (2009)

  10. Cooling of neutron stars

    NASA Technical Reports Server (NTRS)

    Pethick, C. J.

    1992-01-01

    It is at present impossible to predict the interior constitution of neutron stars based on theory and results from laboratory studies. It has been proposed that it is possible to obtain information on neutron star interiors by studying thermal radiation from their surfaces, because neutrino emission rates, and hence the temperature of the central part of a neutron star, depend on the properties of dense matter. The theory predicts that neutron stars cool relatively slowly if their cores are made up of nucleons, and cool faster if the matter is in an exotic state, such as a pion condensate, a kaon condensate, or quark matter. This view has recently been questioned by the discovery of a number of other processes that could lead to copious neutrino emission and rapid cooling.

  11. Modeling cooling coils

    SciTech Connect

    Theerakulpisut, S.; Priprem, S.

    1998-01-01

    Finned-tube heat exchangers commonly used as cooling coils in air conditioning systems undergo complex heat transfer and dehumidification. Due to the presence of water film on the outside surface of the coils, the general approach for an analysis of dry surface is not adequate to predict the performance of such coils. This paper presents a modeling procedure for cooling coils with dehumidification based on the approach of Threlkeld. In order to verify the calculational results of the model, experiments were conducted with an aim to determine the outlet air conditions as well as some other parameters required as the inputs to the model. Comparison between the simulation and experimental results reveals that the model is accurate and suitable for predicting the performance of cooling coils with dehumidification.

  12. Passive containment cooling system

    DOEpatents

    Billig, P.F.; Cooke, F.E.; Fitch, J.R.

    1994-01-25

    A passive containment cooling system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and a gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel and is vented to the drywell. An isolation pool is disposed above the GDCS pool and includes an isolation condenser therein. The condenser has an inlet line disposed in flow communication with the drywell for receiving the non-condensable gas along with any steam released therein following a loss-of-coolant accident (LOCA). The condenser also has an outlet line disposed in flow communication with the drywell for returning to the drywell both liquid condensate produced upon cooling of the steam and the non-condensable gas for reducing pressure within the containment vessel following the LOCA. 1 figure.

  13. IONIZATION COOLING SCENARIO FOR A NEUTRINO FACTORY.

    SciTech Connect

    FERNOW, R.C.; GALLARDO, J.C.; PALMER, R.B.; LEBRUN, P.L.

    2001-06-18

    The neutrino factory program aims to produce well-characterized neutrino fluxes, orders of magnitude larger than those available from conventional beams. An important feature of the machine design is a cooling section for reducing the muon transverse emittance to a level that can be accepted by the downstream accelerators and be contained in the storage ring. We describe simulations of a high-performance ionization cooling channel for the front end of a neutrino factory. The design considered here consists of a solenoidal lattice with alternating polarity and 2.75 m and 1.65 m cell lengths. Simulations show that the cooling increases the phase space density into the acceptance of the following linac by a factor of 3.

  14. Coronal Structures in Cool Stars

    NASA Technical Reports Server (NTRS)

    Oliversen, Ronald (Technical Monitor); Dupree, Andrea K.

    2004-01-01

    Many papers have been published that further elucidate the structure of coronas in cool stars as determined from EUVE, HST, FUSE, Chandra, and XMM-Newton observations. In addition we are exploring the effects of coronas on the He I 1083081 transition that is observed in the infrared. Highlights of these are summarized below including publications during this reporting period and presentations. Ground-based magnetic Doppler imaging of cool stars suggests that active stars have active regions located at high latitudes on their surface. We have performed similar imaging in X-ray to locate the sites of enhanced activity using Chandra spectra. Chandra HETG observations of the bright eclipsing contact binary 44i Boo and Chandra LETG observations for the eclipsing binary VW Cep show X-ray line profiles that are Doppler-shifted by orbital motion. After careful analysis of the spectrum of each binary, a composite line-profile is constructed by adding the individual spectral lines. This high signal-to-noise ratio composite line-profile yields orbital velocities for these binaries that are accurate to 30 km/sec and allows their orbital motion to be studied at higher time resolutions. In conjunction with X-ray lightcurves, the phase-binned composite line-profiles constrain coronal structures to be small and located at high latitudes. These observations and techniques show the power of the Doppler Imaging Technique applied to X-ray line emission.

  15. Mechano-caloric cooling device

    NASA Technical Reports Server (NTRS)

    Frederking, T. H. K.; Luna, Jack; Abbassi, P.; Carandang, R. M.

    1989-01-01

    The mechano-caloric effect is potentially useful in the He II temperature range. Aside from demonstration work, little quantification effort appears to have been known since other refrigeration possibilities have been available for some time. Successful He II use-related system examples are as follows: in space, the utilization of the latent heat of vaporization has been quite successful in vapor-liquid phase separation (VLPS) in conjunction with thermomechanical force application in plugs. In magnet cooling systems, the possibility of using the mechano-caloric cooling effect in conjunction with thermo-mechanical circulation pump schemes, has been assessed (but not quantified yet to the extent desirable). A third example is quoted in conjunction with superfluid wind tunnel studies and liquid helium tow tank for surface vessels respectively. In all of these (partially future) R and D areas, the question of refrigerator effectiveness using the mechano-caloric effect appears to be relevant, possibly in conjunction with questions of reliability and simplicity. The present work is concerned with quantification of phenomena including simplified thermodynamic cycle calculations.

  16. Heat pipe turbine vane cooling

    SciTech Connect

    Langston, L.; Faghri, A.

    1995-12-31

    The applicability of using heat pipe principles to cool gas turbine vanes is addressed in this beginning program. This innovative concept involves fitting out the vane interior as a heat pipe and extending the vane into an adjacent heat sink, thus transferring the vane incident heat transfer through the heat pipe to heat sink. This design provides an extremely high heat transfer rate and a uniform temperature along the vane due to the internal change of phase of the heat pipe working fluid. Furthermore, this technology can also eliminate hot spots at the vane leading and trailing edges and increase the vane life by preventing thermal fatigue cracking. There is also the possibility of requiring no bleed air from the compressor, and therefore eliminating engine performance losses resulting from the diversion of compressor discharge air. Significant improvement in gas turbine performance can be achieved by using heat pipe technology in place of conventional air cooled vanes. A detailed numerical analysis of a heat pipe vane will be made and an experimental model will be designed in the first year of this new program.

  17. Superconductor rotor cooling system

    DOEpatents

    Gamble, Bruce B.; Sidi-Yekhlef, Ahmed; Schwall, Robert E.; Driscoll, David I.; Shoykhet, Boris A.

    2002-01-01

    A system for cooling a superconductor device includes a cryocooler located in a stationary reference frame and a closed circulation system external to the cryocooler. The closed circulation system interfaces the stationary reference frame with a rotating reference frame in which the superconductor device is located. A method of cooling a superconductor device includes locating a cryocooler in a stationary reference frame, and transferring heat from a superconductor device located in a rotating reference frame to the cryocooler through a closed circulation system external to the cryocooler. The closed circulation system interfaces the stationary reference frame with the rotating reference frame.

  18. Superconductor rotor cooling system

    DOEpatents

    Gamble, Bruce B.; Sidi-Yekhlef, Ahmed; Schwall, Robert E.; Driscoll, David I.; Shoykhet, Boris A.

    2004-11-02

    A system for cooling a superconductor device includes a cryocooler located in a stationary reference frame and a closed circulation system external to the cryocooler. The closed circulation system interfaces the stationary reference frame with a rotating reference frame in which the superconductor device is located. A method of cooling a superconductor device includes locating a cryocooler in a stationary reference frame, and transferring heat from a superconductor device located in a rotating reference frame to the cryocooler through a closed circulation system external to the cryocooler. The closed circulation system interfaces the stationary reference frame with the rotating reference frame.

  19. Anomalous law of cooling

    SciTech Connect

    Lapas, Luciano C.; Ferreira, Rogelma M. S.; Rubí, J. Miguel; Oliveira, Fernando A.

    2015-03-14

    We analyze the temperature relaxation phenomena of systems in contact with a thermal reservoir that undergoes a non-Markovian diffusion process. From a generalized Langevin equation, we show that the temperature is governed by a law of cooling of the Newton’s law type in which the relaxation time depends on the velocity autocorrelation and is then characterized by the memory function. The analysis of the temperature decay reveals the existence of an anomalous cooling in which the temperature may oscillate. Despite this anomalous behavior, we show that the variation of entropy remains always positive in accordance with the second law of thermodynamics.

  20. Cyclic cooling algorithm

    SciTech Connect

    Rempp, Florian; Mahler, Guenter; Michel, Mathias

    2007-09-15

    We introduce a scheme to perform the cooling algorithm, first presented by Boykin et al. in 2002, for an arbitrary number of times on the same set of qbits. We achieve this goal by adding an additional SWAP gate and a bath contact to the algorithm. This way one qbit may repeatedly be cooled without adding additional qbits to the system. By using a product Liouville space to model the bath contact we calculate the density matrix of the system after a given number of applications of the algorithm.

  1. Combustor liner cooling system

    DOEpatents

    Lacy, Benjamin Paul; Berkman, Mert Enis

    2013-08-06

    A combustor liner is disclosed. The combustor liner includes an upstream portion, a downstream end portion extending from the upstream portion along a generally longitudinal axis, and a cover layer associated with an inner surface of the downstream end portion. The downstream end portion includes the inner surface and an outer surface, the inner surface defining a plurality of microchannels. The downstream end portion further defines a plurality of passages extending between the inner surface and the outer surface. The plurality of microchannels are fluidly connected to the plurality of passages, and are configured to flow a cooling medium therethrough, cooling the combustor liner.

  2. Reno Industrial Park geothermal district heating system

    SciTech Connect

    Lienau, P.J.

    1997-04-01

    Ten miles south of Reno, on U.S. 395 near the junction of the road to historic Virginia City, is Steamboat Hot Springs, a popular stop for travelers since the mid-1800s. Legend has it that Mark Twain named the geothermal area because it looked and sounded like a chugging Mississippi River paddle-wheeler. It is said when he first saw the steam rising from the ground he exclaimed, {open_quotes}Behold! A Steamboat in the desert.{close_quotes} Over the years, the area has been used for its relaxing and curative qualities by Indians, settlers, and geothermal experts. Since the mid-1980s five geothermal power plants have been built at Steamboat Springs and in December 1996 it was announced that the proposed largest geothermal district heating system in the U.S. would supply an industrial park in the area. The active geothermal area is located within the north-south trending graben like trough between the Carson and Virginia Ranges at the southern end of Truckee Meadows. Hot springs and other geothermal features occur over an area of about one square mile. The mid-basin location is controlled by faulting more or less parallel to the major mountain-front faults. It is believed that the heat source for the system is a cooling magmatic body at depth. The Steamboat geothermal area consists of a deep, high-temperature (215{degrees}C to 240{degrees} C) geothermal system, a shallower, moderate-temperature (160{degrees}C to 18{degrees} C) system, and a number of shallow low-temperature (30{degrees}C to 80{degrees}C) subsystems. The higher temperature systems are used for electric-power generation. It is proposed that the exit fluids from the electric power plants be used for the geothermal district heating system.

  3. 78 FR 3892 - Turlock Irrigation District and Modesto Irrigation District; Notice Clarifying Party Status

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-17

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Turlock Irrigation District and Modesto Irrigation District; Notice Clarifying Party Status On January 9, 2013, the Modesto Irrigation District (Modesto) filed a motion...

  4. Cooling Atomic Gases With Disorder.

    PubMed

    Paiva, Thereza; Khatami, Ehsan; Yang, Shuxiang; Rousseau, Valéry; Jarrell, Mark; Moreno, Juana; Hulet, Randall G; Scalettar, Richard T

    2015-12-11

    Cold atomic gases have proven capable of emulating a number of fundamental condensed matter phenomena including Bose-Einstein condensation, the Mott transition, Fulde-Ferrell-Larkin-Ovchinnikov pairing, and the quantum Hall effect. Cooling to a low enough temperature to explore magnetism and exotic superconductivity in lattices of fermionic atoms remains a challenge. We propose a method to produce a low temperature gas by preparing it in a disordered potential and following a constant entropy trajectory to deliver the gas into a nondisordered state which exhibits these incompletely understood phases. We show, using quantum Monte Carlo simulations, that we can approach the Néel temperature of the three-dimensional Hubbard model for experimentally achievable parameters. Recent experimental estimates suggest the randomness required lies in a regime where atom transport and equilibration are still robust. PMID:26705614

  5. Cooling Atomic Gases With Disorder

    NASA Astrophysics Data System (ADS)

    Paiva, Thereza; Khatami, Ehsan; Yang, Shuxiang; Rousseau, Valéry; Jarrell, Mark; Moreno, Juana; Hulet, Randall G.; Scalettar, Richard T.

    2015-12-01

    Cold atomic gases have proven capable of emulating a number of fundamental condensed matter phenomena including Bose-Einstein condensation, the Mott transition, Fulde-Ferrell-Larkin-Ovchinnikov pairing, and the quantum Hall effect. Cooling to a low enough temperature to explore magnetism and exotic superconductivity in lattices of fermionic atoms remains a challenge. We propose a method to produce a low temperature gas by preparing it in a disordered potential and following a constant entropy trajectory to deliver the gas into a nondisordered state which exhibits these incompletely understood phases. We show, using quantum Monte Carlo simulations, that we can approach the Néel temperature of the three-dimensional Hubbard model for experimentally achievable parameters. Recent experimental estimates suggest the randomness required lies in a regime where atom transport and equilibration are still robust.

  6. Solar-powered cooling system

    SciTech Connect

    Farmer, Joseph C.

    2015-07-28

    A solar-powered adsorption-desorption refrigeration and air conditioning system that uses nanostructural materials such as aerogels, zeolites, and sol gels as the adsorptive media. Refrigerant molecules are adsorbed on the high surface area of the nanostructural material while the material is at a relatively low temperature, perhaps at night. During daylight hours, when the nanostructural materials is heated by the sun, the refrigerant are thermally desorbed from the surface of the aerogel, thereby creating a pressurized gas phase in the vessel that contains the aerogel. This solar-driven pressurization forces the heated gaseous refrigerant through a condenser, followed by an expansion valve. In the condenser, heat is removed from the refrigerant, first by circulating air or water. Eventually, the cooled gaseous refrigerant expands isenthalpically through a throttle valve into an evaporator, in a fashion similar to that in more conventional vapor recompression systems.

  7. Non-equilibrium cooling rate for a collisionally cooled metal-enriched gas

    NASA Astrophysics Data System (ADS)

    Vasiliev, Evgenii O.

    2013-05-01

    We present self-consistent calculations of non-equilibrium (time-dependent) cooling rates for a dust-free collisionally controlled gas in wide ranges of temperature (10 ≤ T ≤ 108 K) and metallicity (10-4 ≤ Z ≤ 2 Z⊙). We confirm that molecular hydrogen dominates cooling at 102 ≲ T ≲ 104 K and Z ≲ 10- 3 Z⊙. We find that the contribution from H2 into the cooling rate around T ˜ (4-5) × 103 K stimulates thermal instability in the metallicity range Z ≲ 10- 2 Z⊙. Isobaric cooling rates are generally lower than isochoric cooling rates, because the associated increase of gas density leads to both more efficient hydrogen recombination and equilibration of the fine-structure level populations. Isochoric cooling means that the ionization fraction remains quite high at T ≲ 104 K - up to ˜0.01 at T ≃ 103 K and Z ≲ 0.1 Z⊙, and even higher at higher metallicity - unlike isobaric cooling, where it is at least an order of magnitude lower. Despite this increase in ionization fraction, the gas-phase formation rate of molecular hydrogen (via H-) decreases with metallicity, because higher metallicity shortens the evolution time. We implement our self-consistent cooling rates into the multidimensional parallel code ZEUS-MP in order to simulate the evolution of a supernova remnant. We compare it to an analogous model with tabulated cooling rates published in previous studies. We find significant differences between the two descriptions, which might appear, for example, in the mixing of the ejected metals in the circumstellar medium.

  8. Emergency cooling system and method

    DOEpatents

    Oosterkamp, W.J.; Cheung, Y.K.

    1994-01-04

    An improved emergency cooling system and method are disclosed that may be adapted for incorporation into or use with a nuclear BWR wherein a reactor pressure vessel (RPV) containing a nuclear core and a heat transfer fluid for circulation in a heat transfer relationship with the core is housed within an annular sealed drywell and is fluid communicable therewith for passage thereto in an emergency situation the heat transfer fluid in a gaseous phase and any noncondensibles present in the RPV, an annular sealed wetwell houses the drywell, and a pressure suppression pool of liquid is disposed in the wetwell and is connected to the drywell by submerged vents. The improved emergency cooling system and method has a containment condenser for receiving condensible heat transfer fluid in a gaseous phase and noncondensibles for condensing at least a portion of the heat transfer fluid. The containment condenser has an inlet in fluid communication with the drywell for receiving heat transfer fluid and noncondensibles, a first outlet in fluid communication with the RPV for the return to the RPV of the condensed portion of the heat transfer fluid and a second outlet in fluid communication with the drywell for passage of the noncondensed balance of the heat transfer fluid and the noncondensibles. The noncondensed balance of the heat transfer fluid and the noncondensibles passed to the drywell from the containment condenser are mixed with the heat transfer fluid and the noncondensibles from the RPV for passage into the containment condenser. A water pool is provided in heat transfer relationship with the containment condenser and is thermally communicable in an emergency situation with an environment outside of the drywell and the wetwell for conducting heat transferred from the containment condenser away from the wetwell and the drywell. 5 figs.

  9. Muon Beam Helical Cooling Channel Design

    SciTech Connect

    Johnson, Rolland; Ankenbrandt, Charles; Flanagan, G.; Kazakevich, G.M.; Marhauser, Frank; Neubauer, Michael; Roberts, T.; Yoshikawa, C.; Derbenev, Yaroslav; Morozov, Vasiliy; Kashikhin, V.S.; Lopes, Mattlock; Tollestrup, A.; Yonehara, Katsuya; Zloblin, A.

    2013-06-01

    The Helical Cooling Channel (HCC) achieves effective ionization cooling of the six-dimensional (6d) phase space of a muon beam by means of a series of 21st century inventions. In the HCC, hydrogen-pressurized RF cavities enable high RF gradients in strong external magnetic fields. The theory of the HCC, which requires a magnetic field with solenoid, helical dipole, and helical quadrupole components, demonstrates that dispersion in the gaseous hydrogen energy absorber provides effective emittance exchange to enable longitudinal ionization cooling. The 10-year development of a practical implementation of a muon-beam cooling device has involved a series of technical innovations and experiments that imply that an HCC of less than 300 m length can cool the 6d emittance of a muon beam by six orders of magnitude. We describe the design and construction plans for a prototype HCC module based on oxygen-doped hydrogen-pressurized RF cavities that are loaded with dielectric, fed by magnetrons, and operate in a superconducting helical solenoid magnet.

  10. Measure Guideline: Ventilation Cooling

    SciTech Connect

    Springer, D.; Dakin, B.; German, A.

    2012-04-01

    The purpose of this measure guideline is to provide information on a cost-effective solution for reducing cooling system energy and demand in homes located in hot-dry and cold-dry climates. This guideline provides a prescriptive approach that outlines qualification criteria, selection considerations, and design and installation procedures.

  11. Designing Cool Components

    NASA Technical Reports Server (NTRS)

    2000-01-01

    A NASA SBIR contract served as the beginning for the development of Daat Research Corporation's Coolit software. Coolit is a unique computational fluid dynamics (CFD) application aimed at thermal and cooling design problems. Coolit can generate 3-D representations of the thermofluid environment and "sketch" the component on the computer. The software modeling reduces time and effort in prototype building and testing.

  12. Warm and Cool Cityscapes

    ERIC Educational Resources Information Center

    Jubelirer, Shelly

    2012-01-01

    Painting cityscapes is a great way to teach first-grade students about warm and cool colors. Before the painting begins, the author and her class have an in-depth discussion about big cities and what types of buildings or structures that might be seen in them. They talk about large apartment and condo buildings, skyscrapers, art museums,…

  13. Warm and Cool Cityscapes

    ERIC Educational Resources Information Center

    Jubelirer, Shelly

    2012-01-01

    Painting cityscapes is a great way to teach first-grade students about warm and cool colors. Before the painting begins, the author and her class have an in-depth discussion about big cities and what types of buildings or structures that might be seen in them. They talk about large apartment and condo buildings, skyscrapers, art museums,

  14. Transpiration Cooling Experiment

    NASA Technical Reports Server (NTRS)

    Song, Kyo D.; Ries, Heidi R.; Scotti, Stephen J.; Choi, Sang H.

    1997-01-01

    The transpiration cooling method was considered for a scram-jet engine to accommodate thermally the situation where a very high heat flux (200 Btu/sq. ft sec) from hydrogen fuel combustion process is imposed to the engine walls. In a scram-jet engine, a small portion of hydrogen fuel passes through the porous walls of the engine combustor to cool the engine walls and at the same time the rest passes along combustion chamber walls and is preheated. Such a regenerative system promises simultaneously cooling of engine combustor and preheating the cryogenic fuel. In the experiment, an optical heating method was used to provide a heat flux of 200 Btu/sq. ft sec to the cylindrical surface of a porous stainless steel specimen which carried helium gas. The cooling efficiencies by transpiration were studied for specimens with various porosity. The experiments of various test specimens under high heat flux have revealed a phenomenon that chokes the medium flow when passing through a porous structure. This research includes the analysis of the system and a scaling conversion study that interprets the results from helium into the case when hydrogen medium is used.

  15. ELECTRON COOLING FOR RHIC.

    SciTech Connect

    BEN-ZVI,I.

    2001-05-13

    The Accelerator Collider Department (CAD) at Brookhaven National Laboratory is operating the Relativistic Heavy Ion Collider (RHIC), which includes the dual-ring, 3.834 km circumference superconducting collider and the venerable AGS as the last part of the RHIC injection chain. CAD is planning on a luminosity upgrade of the machine under the designation RHIC II. One important component of the RHIC II upgrade is electron cooling of RHIC gold ion beams. For this purpose, BNL and the Budker Institute of Nuclear Physics in Novosibirsk entered into a collaboration aimed initially at the development of the electron cooling conceptual design, resolution of technical issues, and finally extend the collaboration towards the construction and commissioning of the cooler. Many of the results presented in this paper are derived from the Electron Cooling for RHIC Design Report [1], produced by the, BINP team within the framework of this collaboration. BNL is also collaborating with Fermi National Laboratory, Thomas Jefferson National Accelerator Facility and the University of Indiana on various aspects of electron cooling.

  16. Electron Cooling of RHIC

    SciTech Connect

    I. Ben-Zvi; D.S. Barton; D.B. Beavis; M. Blaskiewicz; J.M. Brennan; A. Burrill; R. Calaga; P. Cameron; X.Y. Chang; R. Connolly; Yu.I. Eidelman; A.V. Fedotov; W. Fischer; D.M. Gassner; H. Hahn; M. Harrison; A. Hershcovitch; H.-C. Hseuh; A.K. Jain; P.D.J. Johnson; D. Kayran; J. Kewisch; R.F. Lambiase; V. Litvinenko; W.W. MacKay; G.J. Mahler; N. Malitsky; G.T. McIntyre; W. Meng; K.A.M. Mirabella; C. Montag; T.C.N. Nehring; T. Nicoletti; B. Oerter; G. Parzen; D. Pate; J. Rank; T. Rao; T. Roser; T. Russo; J. Scaduto; K. Smith; D. Trbojevic; G. Wang; J. Wei; N.W.W. Williams; K.-C. Wu; V. Yakimenko; A. Zaltsman; Y. Zhao; D.T. Abell; D.L. Bruhwiler; H. Bluem; A. Burger; M.D. Cole; A.J. Favale; D. Holmes; J. Rathke; T. Schultheiss; A.M.M. Todd; A.V. Burov; S. Nagaitsev; J.R. Delayen; Y.S. Derbenev; L. W. Funk; P. Kneisel; L. Merminga; H.L. Phillips; J.P. Preble; I. Koop; V.V. Parkhomchuk; Y.M. Shatunov; A.N. Skrinsky; I. Koop; V.V. Parkhomchuk; Y.M. Shatunov; A.N. Skrinsky; J.S. Sekutowicz

    2005-05-16

    We report progress on the R&D program for electron-cooling of the Relativistic Heavy Ion Collider (RHIC). This electron cooler is designed to cool 100 GeV/nucleon at storage energy using 54 MeV electrons. The electron source will be a superconducting RF photocathode gun. The accelerator will be a superconducting energy recovery linac. The frequency of the accelerator is set at 703.75 MHz. The maximum electron bunch frequency is 9.38 MHz, with bunch charge of 20 nC. The R&D program has the following components: The photoinjector and its photocathode, the superconducting linac cavity, start-to-end beam dynamics with magnetized electrons, electron cooling calculations including benchmarking experiments and development of a large superconducting solenoid. The photoinjector and linac cavity are being incorporated into an energy recovery linac aimed at demonstrating ampere class current at about 20 MeV. A Zeroth Order Design Report is in an advanced draft state, and can be found on the web at http://www.agsrhichome.bnl.gov/eCool/.

  17. COOLING TOWER PLUME MODEL

    EPA Science Inventory

    A review of recently reported cooling tower plume models yields none that is universally accepted. The entrainment and drag mechanisms and the effect of moisture on the plume trajectory are phenomena which are treated differently by various investigators. In order to better under...

  18. Guide to Cool Roofs

    SciTech Connect

    2011-02-01

    Traditional dark-colored roofing materials absorb sunlight, making them warm in the sun and increasing the need for air conditioning. White or special "cool color" roofs absorb less sunlight, stay cooler in the sun and transmit less heat into the building.

  19. Comment on the Word 'Cooling' as it is Used in Beam Physics

    SciTech Connect

    Sessler, Andrew M.

    2006-03-20

    Beam physicists use the word 'cooling' differently than it is used by the general public or even by other physicists. It is recommended that we no longer use this term, but replace it with some other term such as: 'Phase Density Cooling' (PDF) or 'damping', or alternatively 'Liouville Cooling', which would make our field more easily understood by outsiders.

  20. Curved film cooling admission tube

    NASA Technical Reports Server (NTRS)

    Graham, R. W.; Papell, S. S. (Inventor)

    1980-01-01

    Effective film cooling to protect a wall surface from a hot fluid which impinges on or flows along the surface is provided. A film of cooling fluid having increased area is provided by changing the direction of a stream of cooling fluid through an angle of from 135 deg. to 165 deg. before injecting it through the wall into the hot flowing gas. The 1, cooling fluid is injected from an orifice through a wall into a hot flowing gas at an angle to form a cooling fluid film. Cooling fluid is supplied to the orifice from a cooling fluid source via a turbulence control passageway having a curved portion between two straight portions. The angle through which the direction of the cooling fluid is turned results in less mixing of the cooling fluid with the hot gas, thereby substantially increasing the length of the film in a downstream direction.

  1. Turbomachine rotor with improved cooling

    DOEpatents

    Hultgren, K.G.; McLaurin, L.D.; Bertsch, O.L.; Lowe, P.E.

    1998-05-26

    A gas turbine rotor has an essentially closed loop cooling air scheme in which cooling air drawn from the compressor discharge air that is supplied to the combustion chamber is further compressed, cooled, and then directed to the aft end of the turbine rotor. Downstream seal rings attached to the downstream face of each rotor disc direct the cooling air over the downstream disc face, thereby cooling it, and then to cooling air passages formed in the rotating blades. Upstream seal rings attached to the upstream face of each disc direct the heated cooling air away from the blade root while keeping the disc thermally isolated from the heated cooling air. From each upstream seal ring, the heated cooling air flows through passages in the upstream discs and is then combined and returned to the combustion chamber from which it was drawn. 5 figs.

  2. Turbomachine rotor with improved cooling

    DOEpatents

    Hultgren, Kent Goran; McLaurin, Leroy Dixon; Bertsch, Oran Leroy; Lowe, Perry Eugene

    1998-01-01

    A gas turbine rotor has an essentially closed loop cooling air scheme in which cooling air drawn from the compressor discharge air that is supplied to the combustion chamber is further compressed, cooled, and then directed to the aft end of the turbine rotor. Downstream seal rings attached to the downstream face of each rotor disc direct the cooling air over the downstream disc face, thereby cooling it, and then to cooling air passages formed in the rotating blades. Upstream seal rings attached to the upstream face of each disc direct the heated cooling air away from the blade root while keeping the disc thermally isolated from the heated cooling air. From each upstream seal ring, the heated cooling air flows through passages in the upstream discs and is then combined and returned to the combustion chamber from which it was drawn.

  3. PCM Passive Cooling System Containing Active Subsystems

    NASA Technical Reports Server (NTRS)

    Blanding, David E.; Bass, David I.

    2005-01-01

    A multistage system has been proposed for cooling a circulating fluid that is subject to intermittent intense heating. The system would be both flexible and redundant in that it could operate in a basic passive mode, either sequentially or simultaneously with operation of a first, active cooling subsystem, and either sequentially or simultaneously with a second cooling subsystem that could be active, passive, or a combination of both. This flexibility and redundancy, in combination with the passive nature of at least one of the modes of operation, would make the system more reliable, relative to a conventional cooling system. The system would include a tube-in-shell heat exchanger, within which the space between the tubes would be filled with a phase-change material (PCM). The circulating hot fluid would flow along the tubes in the heat exchanger. In the basic passive mode of operation, heat would be conducted from the hot fluid into the PCM, wherein the heat would be stored temporarily by virtue of the phase change.

  4. ELECTRON COOLING STUDY FOR MEIC

    SciTech Connect

    He, Zhang; Douglas, David R.; Derbenev, Yaroslav S.; Zhang, Yuhong

    2015-09-01

    Electron cooling of the ion beams is one critical R&D to achieve high luminosities in JLab's MEIC proposal. In the present MEIC design, a multi-staged cooling scheme is adapted, which includes DC electron cooling in the booster ring and bunched beam electron cooling in the collider ring at both the injection energy and the collision energy. We explored the feasibility of using both magnetized and non-magnetized electron beam for cooling, and concluded that a magnetized electron beam is necessary. Electron cooling simulation results for the newly updated MEIC design is also presented.

  5. A Review of Neshaminy School District's Exemplary Vocational-Technical English/Language Arts Program Against Commonwealth Goals for Quality Education. Focusing on Goals One, Three and Seven: Annual Phase I Report, Addendum and Appendices.

    ERIC Educational Resources Information Center

    Neshaminy School District, Langhorne, PA.

    The purpose of this project was to develop a more relevant and utilitarian English/language arts and communications media program for technical school students in Grades 10-12. During Phase I, the curriculum was developed by a team of teachers and implemented at each of the grade levels. Evaluation of the program was accomplished through surveying…

  6. Laser-Cooling-Assisted Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Schneider, Christian; Schowalter, Steven J.; Chen, Kuang; Sullivan, Scott T.; Hudson, Eric R.

    2014-09-01

    Mass spectrometry is used in a wide range of scientific disciplines including proteomics, pharmaceutics, forensics, and fundamental physics and chemistry. Given this ubiquity, there is a worldwide effort to improve the efficiency and resolution of mass spectrometers. However, the performance of all techniques is ultimately limited by the initial phase-space distribution of the molecules being analyzed. Here, we dramatically reduce the width of this initial phase-space distribution by sympathetically cooling the input molecules with laser-cooled, cotrapped atomic ions, improving both the mass resolution and detection efficiency of a time-of-flight mass spectrometer by over an order of magnitude. Detailed molecular-dynamics simulations verify the technique and aid with evaluating its effectiveness. This technique appears to be applicable to other types of mass spectrometers.

  7. Climate changes and recent glacier behaviour in the Chilean Lake District

    NASA Astrophysics Data System (ADS)

    Bown, Francisca; Rivera, Andrés

    2007-10-01

    Atmospheric temperatures measured at the Chilean Lake District (38°-42°S) showed contrasting trends during the second half of the 20th century. The surface cooling detected at several meteorological stations ranged from - 0.014 to - 0.021 °C a - 1 , whilst upper troposphere (850-300 gpm) records at radiosonde of Puerto Montt (41°26'S/73°07'W) revealed warming between 0.019 and 0.031 °C a - 1 . Regional rainfall data collected from 1961 to 2000 showed the overall decrease with a maximum rate of - 15 mm a - 2 at Valdivia st. (39°38'S/73°05'W). These ongoing climatic changes, especially the precipitation reduction, seem to be related to El Niño-Southern Oscillation (ENSO) phenomena which has been more frequent after 1976. Glaciers within the Chilean Lake District have significantly retreated during recent decades, in an apparent out-of-phase response to the regional surface cooling. Moreover, very little is known about upper troposphere changes and how they can enhance the glacier responses. In order to analyse their behaviour in the context of the observed climate changes, Casa Pangue glacier (41°08'S/71°52'W) has been selected and studied by comparing Digital Elevation Models (DEMs) computed at three different dates throughout the last four decades. This approach allowed the determination of ice elevation changes between 1961 and 1998, yielding a mean thinning rate of - 2.3 ± 0.6 m a - 1 . Strikingly, when ice thinning is computed for the period between 1981 and 1998, the resulting rate is 50% higher (- 3.6 ± 0.6 m a - 1 ). This enhanced trend and the related area loss and frontal retreat suggests that Casa Pangue might currently be suffering negative mass balances in response to the upper troposphere warming and decreased precipitation of the last 25-30 yr, as well as debris cover would not prevent the glacier from a fast reaction to climate forcing. Most of recent glaciological studies regarding Andean glaciers have concentrated on low altitude changes, namely frontal variations, however, in order to better understand the regional glacier changes, new data are necessary, especially from the accumulation areas.

  8. Physiologic and Functional Responses of MS Patients to Body Cooling Using Commercially Available Cooling Garments

    NASA Technical Reports Server (NTRS)

    Ku, Yu-Tsuan E.; Montgomery, Leslie D.; Lee, Hank C.; Luna, Bernadette; Webbon, Bruce W.; Mead, Susan C. (Technical Monitor)

    1999-01-01

    Personal cooling systems are widely used in industrial and aerospace environments to alleviate thermal stress. Increasingly they are also used by heat sensitive multiple sclerosis (HSMS) patients to relieve symptoms and improve quality of life. There are a variety of cooling systems commercially available to the MS community. However, little information is available regarding the comparative physiological changes produced by routine operation of these various systems. The objective of this study was to document and compare the patient response to two passive cooling vests and one active cooling garment. The Life Enhancement Technology, Inc. (LET) lightweight active cooling vest with cap, the MicroClimate Systems (MCS) Change of Phase garment, and the Steele Vest were each used to cool 13 male and 13 female MS subjects (31 to 67 yr.) in this study. The subjects, seated in an upright position at normal room temperature (approximately 22 C), were tested with one of the cooling garments. Oral, fight and left ear temperatures were logged manually every 5 min. An-n, leg, chest and rectal temperatures; heart rate; and respiration were recorded continuously on a U.F.I., Inc. Biolog ambulatory monitor. Each subject was given a series of subjective and objective evaluation tests before and after cooling. The LET and Steele vests test groups had similar, significant (P less than 0.01) cooling effects on oral and ear canal temperature, which decreased approximately 0.4 C, and 0.3 C, respectively. Core temperature increased (N.S.) with all three vests during cooling. The LET vest produced the coldest (P less than 0.01) skin temperature. Overall, the LET vest provided the most improvement on subjective and objective performance measures. These results show that the garment configurations tested do not elicit a similar thermal response in all MS patients. Cooling with the LET active garment configuration resulted in the lowest body temperatures for the MS subjects; cooling with the MCS vest was least effective. For functional responses, the LET test group performed better than the other two vests.

  9. Energy Sources and Systems Analysis: 40 South Lincoln Redevelopment District (Short Report)

    SciTech Connect

    Not Available

    2011-08-01

    This report presents the a brief overview of the results of a case study to analyze district energy systems for their potential use in a project that involves redeveloping 270 units of existing public housing, along with other nearby sites. When complete, the redevelopment project will encompass more than 900 mixed-income residential units, commercial and retail properties, and open space. The analysis estimated the hourly heating, cooling, domestic hot water, and electric loads required by the community; investigated potential district system technologies to meet those needs; and researched available fuel sources to power such systems. A full report of this case study is also available.

  10. Energy Sources and Systems Analysis: 40 South Lincoln Redevelopment District (Full Report)

    SciTech Connect

    Not Available

    2011-08-01

    This report presents the results of a case study to analyze district energy systems for their potential use in a project that involves redeveloping 270 units of existing public housing, along with other nearby sites. When complete, the redevelopment project will encompass more than 900 mixed-income residential units, commercial and retail properties, and open space. The analysis estimated the hourly heating, cooling, domestic hot water, and electric loads required by the community; investigated potential district system technologies to meet those needs; and researched available fuel sources to power such systems.

  11. Survey of Burglary and Vandalism Occurrence and Preventative Measures in Twenty-Five Large California School Districts. Summary Report.

    ERIC Educational Resources Information Center

    Fresno City Unified School District, CA. Office of Planning and Research Services.

    Twenty-three California school districts responded to a burglary and vandalism survey conducted by the Fresno Unified School District Burglary and Vandalism Prevention Project, which represents the first phase of a developing program to reduce vandalism occurrences and improve recovery of losses. This summary compiles survey data on 18,000…

  12. Electrocaloric energy efficiency and cooling power

    NASA Astrophysics Data System (ADS)

    Mathur, Neil

    2014-03-01

    How much energy is required to drive electrocaloric effects near ferroelectric phase transitions? I will compare electrocaloric ceramic and polymer films with each other, with magnetocaloric materials (exploited in over 40 prototype refrigerators), and with elastocaloric materials. I will also discuss the cooling power that could be achieved in electrocaloric heat pumps based on multilayer capacitors in which heat flow is modelled using finite element analysis.

  13. MUON COOLING IN THE RFOFO RING COOLER.

    SciTech Connect

    FERNOW,R.C.BERG,J.S.GALLARDO,J.C.PALMER,R.B.

    2003-05-12

    The performance of the ring described here compares favorably with the linear cooling channel used in the second U.S. Neutrino Factory Study. The 6D phase space density of an idealized ring is increased by a factor of 238, compared with the linear channel's factor of only 15. The simulations make use of fully realistic magnetic fields, and include absorber and rf cavity windows, and empty lattice cells for injection/extraction.

  14. Desiccant-based, heat actuated cooling assessment for DHC systems; Quarterly report, August 1, 1989--October 31, 1989

    SciTech Connect

    Patch, K.D.; DiBella, F.; Becker, F.E.

    1989-01-01

    This is Second Quarterly Report for DOE Project {number_sign} FG01-89CE26593 entitled: ``Desiccant-Based, Heat Actuated Cooling Assessment for DHC Systems.`` The goal of the project is to perform a conceptual design, systems analysis and case study evaluation of a application of a desiccant based cooling design within a district heating and cooling system. This Quarterly Report covers project work conducted from August 1, 1989 to October 31, 1989. The goals of the project have their basis in the desire to lower the operating temperature of the transport medium in a district heating system, but still enable cooling via that transport medium. At this time a district heating and cooling system must use a four-pipe heating ad cooling delivery system -- two pipes for hot water supply and return and two pipes for chilled water supply and return if both heating and cooling are to be provided. Unfortunately, such a four-pipe system is expensive, especially for existing D. H. systems that already have a two-pipe system installed. 1 fig.

  15. Desiccant-based, heat actuated cooling assessment for DHC systems; Quarterly report, November 1, 1989--January 31, 1990

    SciTech Connect

    Patch, K.D.; DiBella, F.; Becker, F.E.

    1990-01-01

    This is the Third Quarterly Report for DOE Project Number FG01- 89CE26593 entitled: ``Desiccant-Based, Heat Actuated Cooling Assessment for DHC Systems.`` The goal of the project is to perform a conceptual design, systems analysis and case study evaluation of an application of a desiccant based cooling design within a district heating and cooling system. This Quarterly Report covers project work conducted from November 1, 1989 to January 31, 1990. The goals of the project have their basis in the desire to lower the operating temperature of the transport medium in a district heating system, but still enable cooling via that transport medium. At this time a district heating and cooling system must use a four-pipe heating and cooling delivery system -- two pipes for hot water supply and return and two pipes for chilled water supply and return if both heating and cooling are to be provided. Unfortunately, such a four-pipe system is expensive, especially for existing D. H. systems that already have a two-pipe system installed. 36 figs.

  16. Congressional District Visits in August

    NASA Astrophysics Data System (ADS)

    Hoover, Fushcia

    2014-08-01

    In preparation for the U.S. congressional recess, AGU Public Affairs hosted an instructional webinar about meeting with legislators and their staff at their district offices. Congress is on recess, with most members back in their districts to reconnect with their constituents. The August recess is a great opportunity for AGU members to schedule meetings with their legislators to talk about the importance of their research and the value of science funding. In these meetings, members can initiate a connection with their senator or representative that will allow them to build a relationship as a valuable resource.

  17. STOCHASTIC COOLING FOR BUNCHED BEAMS.

    SciTech Connect

    BLASKIEWICZ, M.

    2005-05-16

    Problems associated with bunched beam stochastic cooling are reviewed. A longitudinal stochastic cooling system for RHIC is under construction and has been partially commissioned. The state of the system and future plans are discussed.

  18. Electron Cooling of Bunched Beams

    SciTech Connect

    Uesugi, T.; Noda, K.; Syresin, E.; Meshkov, I.; Shibuya, S.

    2006-03-20

    Experiments of electron cooling have been done with the HIMAC synchrotron in NIRS. Limitation on cooled beam-sizes in longitudianl and transverse spaces were measured. The effect of space-charge field and intra-beam scattering are investigated.

  19. Radial turbine cooling

    NASA Technical Reports Server (NTRS)

    Roelke, Richard J.

    1992-01-01

    Radial turbines have been used extensively in many applications including small ground based electrical power generators, automotive engine turbochargers and aircraft auxiliary power units. In all of these applications the turbine inlet temperature is limited to a value commensurate with the material strength limitations and life requirements of uncooled metal rotors. To take advantage of all the benefits that higher temperatures offer, such as increased turbine specific power output or higher cycle thermal efficiency, requires improved high temperature materials and/or blade cooling. Extensive research is on-going to advance the material properties of high temperature superalloys as well as composite materials including ceramics. The use of ceramics with their high temperature potential and low cost is particularly appealing for radial turbines. However until these programs reach fruition the only way to make significant step increases beyond the present material temperature barriers is to cool the radial blading.

  20. Cooling Floor AC Systems

    NASA Astrophysics Data System (ADS)

    Jun, Lu; Hao, Ding; Hong, Zhang; Ce, Gao Dian

    The present HVAC equipments for the residential buildings in the Hot-summer-and-Cold-winter climate region are still at a high energy consuming level. So that the high efficiency HVAC system is an urgently need for achieving the preset government energy saving goal. With its advantage of highly sanitary, highly comfortable and uniform of temperature field, the hot-water resource floor radiation heating system has been widely accepted. This paper has put forward a new way in air-conditioning, which combines the fresh-air supply unit and such floor radiation system for the dehumidification and cooling in summer or heating in winter. By analyze its advantages and limitations, we found that this so called Cooling/ Heating Floor AC System can improve the IAQ of residential building while keep high efficiency quality. We also recommend a methodology for the HVAC system designing, which will ensure the reduction of energy cost of users.