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. Phase two laboratory testing of Direct Freeze ice slurry district cooling

    SciTech Connect

    Winters, P.J.

    1991-04-01

    This report documents the laboratory development progress of a proprietary ice production technology (Direct Freeze) for ice-water slurry district cooling systems. The current work builds on a previous Phase 1 effort performed for the US Department of Energy (DOE). The scope of the current Phase 2 effort was divided into two separate areas. The first, Ice Slurry Hydraulic Characterization Tests, involved the measurement of the hydraulic characteristics of an ice-water slurry system over a wide range of conditions with no oil present in the system. The second, Ice Slurry Cooling Simulation Tests, characterized the real-time operation of a Direct Freeze district cooling system using a bench scale simulation loop. This report documents and analyzes the technical results from these Phase 2 tests and also expands on the Phase 1 economic evaluation. Future studies should identify a replacement for CFC-114 in the Direct Freeze process and identify ways to avoid process line ice blockages. 24 refs., 19 figs., 5 tabs.

  3. 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.

  4. 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.

  5. 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.

  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. Maximizing peak cooling capacity in district cooling distribution systems

    SciTech Connect

    Winters, P.J.; Hansen, D.W.; Andrepont, J.S.

    1996-12-31

    Cooling capacity in District Cooling distribution systems is identified as a major factor affecting the capital and operating costs of District Cooling systems. Increasing peak cooling capacity for fixed pipeline sizes has a significant potential benefit for the economics of District Cooling. The various methods (some commercially available, and others which are developmental) for achieving increased peak delivery capacity in a District Cooling distribution system are outlined and briefly reviewed. They include: (1) lowering Chilled Water Supply (CHWS) temperatures and/or raising Chilled Water Return (CHWR) temperatures, (2) the use of Friction Reducing Additives (FRAs), (3) the use of pumpable phase-change materials (e.g. ice-water slurries or wax-water slurries), (4) the use of distributed (satellite) chiller plants, (5) the use of distributed Thermal Energy Storage (TES) units, and (6) the use of low temperature brines (such as water-glycols or proprietary fluids). Case studies are presented to illustrate and quantify the benefits for several of the currently commercial options, including higher CHW temperature differentials, distributed TES, and the use of low temperature brine in the distribution system.

  8. 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.

  9. 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.

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

    SciTech Connect

    Not Available

    1984-01-31

    The technical information in the report, includes staged development of district heating systems, central power station retrofit, intermediate and peaking/backup thermal plants, transmission and distribution, user connections, and alternatives to district heating. Discussion of heat pumps, cooling, waste heat recovery, small cogeneration and/or solid fuel-burning plants, solar alternatives to district heating and nuclear district heating are included.

  11. Integrating district cooling with cogeneration

    SciTech Connect

    Spurr, M.

    1996-11-01

    Chillers can be driven with cogenerated thermal energy, thereby offering the potential to increase utilization of cogeneration throughout the year. However, cogeneration decreases electric output compared to condensing power generation in power plants using a steam cycle (steam turbine or gas turbine combined cycle plants). The foregone electric production increases with increasing temperature of heat recovery. Given a range of conditions for key variables (such as cogeneration utilization, chiller utilization, cost of fuel, value of electricity, value of heat and temperature of heat recovered), how do technology alternatives for combining district cooling with cogeneration compare? This paper summarizes key findings from a report recently published by the International Energy Agency which examines the energy efficiency and economics of alternatives for combining cogeneration technology options (gas turbine simple cycle, diesel engine, steam turbine, gas turbine combined cycle) with chiller options (electric centrifugal, steam turbine centrifugal one-stage steam absorption, two-stage steam absorption, hot water absorption).

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. Impact of advanced fluids on costs of district cooling systems

    SciTech Connect

    Choi, U.S.; France, D.M.; Knodel, B.D. |

    1992-07-01

    Three alternate fluids, ice-water slurry, friction reduction additive and the combination of them, have been compared for use in District Cooling Systems (DCS). The effect of the fluids on cost and cooling capacities were considered for the two cases of new and existing DCS separately. Two criteria were used in comparisons among fluids in each case: constant pumping power which allows for the most benefit, and constant velocity which is more practical consideration. An economic assessment for a 500 ton system shows a potential cost difference in the total pipe cost for a new system of 70% when a 30% ice slurry is used in place of chilled water. The pipe diameter is reduced to 40% using the slurry. These results apply to the constant comparison and are independent of the use of additive. Friction reduction additives serve to reduce pumping power and pressure drop. The ice-water slurry also has a significant impact on existing district cooling systems. It can potentially expand the cooling capacity by 500% without new piping being installed while maintaining the same pumping power, velocity and pressure-drop as the chilled water system. Again, friction reduction additives serve to reduce pumping power and pressure-drop. They do not influence cooling capacity. The cost for expanding the piping to increase the cooling capacity by the same amount by the use of conventional district cooling technology has been shown to be extremely high compared to the ice-water slurry system.

  9. Impact of advanced fluids on costs of district cooling systems

    SciTech Connect

    Choi, U.S. ); France, D.M.; Knodel, B.D. Illinois Univ., Chicago, IL . Dept. of Mechanical Engineering)

    1992-01-01

    Three alternate fluids, ice-water slurry, friction reduction additive and the combination of them, have been compared for use in District Cooling Systems (DCS). The effect of the fluids on cost and cooling capacities were considered for the two cases of new and existing DCS separately. Two criteria were used in comparisons among fluids in each case: constant pumping power which allows for the most benefit, and constant velocity which is more practical consideration. An economic assessment for a 500 ton system shows a potential cost difference in the total pipe cost for a new system of 70% when a 30% ice slurry is used in place of chilled water. The pipe diameter is reduced to 40% using the slurry. These results apply to the constant comparison and are independent of the use of additive. Friction reduction additives serve to reduce pumping power and pressure drop. The ice-water slurry also has a significant impact on existing district cooling systems. It can potentially expand the cooling capacity by 500% without new piping being installed while maintaining the same pumping power, velocity and pressure-drop as the chilled water system. Again, friction reduction additives serve to reduce pumping power and pressure-drop. They do not influence cooling capacity. The cost for expanding the piping to increase the cooling capacity by the same amount by the use of conventional district cooling technology has been shown to be extremely high compared to the ice-water slurry system.

  10. Solid oxide fuel cell application in district cooling

    NASA Astrophysics Data System (ADS)

    Al-Qattan, Ayman; ElSherbini, Abdelrahman; Al-Ajmi, Kholoud

    2014-07-01

    This paper presents analysis of the performance of a combined cooling and power (CCP) system for district cooling. The cogeneration system is designed to provide cooling for a low-rise residential district of 27,300 RT (96 MWc). A solid oxide fuel cell (SOFC) generates electric power to operate chillers, and the exhaust fuel and heat from the SOFC run gas turbines and absorption chillers. Thermal energy storage is utilized to reduce system capacity. Part-load operation strategies target maximizing energy efficiency. The operation of the system is compared through an hourly simulation to that of packaged air-conditioning units typically used to cool homes. The CCP system with the district cooling arrangement improves the cooling-to-fuel efficiency by 346%. The peak power requirement is reduced by 57% (24 MW) and the total fuel energy is reduced by 54% (750 TJ y-1). The system cuts annual carbon dioxide emissions to less than half and reduces other harmful emissions. A cost analysis of the system components and operation resulted in a 53% reduction in the cost per ton-hour of cooling over traditional systems.

  11. 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.

  12. Conceptual design phase of a district heating and cooling plant with cogeneration to serve James Madison University and the Harrisonburg Electric Commission

    SciTech Connect

    Belcher, J.B.

    1995-12-31

    A unique opportunity for cooperation and community development exists in Harrisonburg, Virginia. James Madison University, located in Harrisonburg, is undergoing an aggressive growth plan of its academic base which also includes the physical expansion of its campus. The City of Harrisonburg is presently supplying steam to meet a portion of the heating needs of the existing James Madison campus from a city owned and operated waste-to-energy plant. In an effort of cooperation, Harrisonburg and James Madison University have now negotiated an agreement for the city to provide all of the heating and cooling requirements of the new campus expansion. In another unique turn of events, the local electrical power distributor, Harrisonburg Electric Commission, approached the city concerning the inclusion of cogeneration in the project in order to reduce and maintain existing electric rates thus further benefiting the community. Through the cooperation of these three entities, the conceptual design phase of the project has been completed. The plant design developed through this process includes 3,000 tons of chilled water capacity, an additional 64,000 lb/hr of steam capacity and 2.5 MW of cogeneration capacity. This paper describes the conceptual design process for this interesting project.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. Energy and economic implications of combining district cooling with cogeneration

    SciTech Connect

    Spurr, M.; Larsson, I.

    1995-12-31

    Chillers can be driven with cogenerated thermal energy, thereby offering the potential to increase utilization of cogeneration throughout the year. However, cogeneration decreases electric output compared to condensing power generation. The foregone electric production increases with increasing temperature of heat recovery. The economics of alternatives for combining district cooling with cogeneration depend on many variables, including cogeneration utilization, chiller utilization, value of electricity, value and temperature of heat recovered and other factors.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. A novel concept for heat transfer fluids used in district cooling systems

    SciTech Connect

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

    1991-01-04

    Low-temperature phase-change materials (PCMS) were mixed with water to enhance the performance of heat transfer fluid. Several PCMs were tested in a laboratory-scale test loop to check their suitability to district cooling applications. The phase-change temperatures and latent heats of fusion of tetradecane, pentadecane, and hexadecane paraffin waxes were measured using a differential scanning calorimeter. 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. For 10% and 25% PCM-water slurries, the heat transfer enhancement was found to be approximately 18 and 30 percent over the value of water, respectively. It was also found that, in the turbulent region, there is only a minor pumping penalty from the addition of up to 25% PCM to the water. It was demonstrated that pentadecane does not clog in a glass-tube chiller, and continuous pumping below its freezing, point (9.9[degrees]C):was successfully carried out in a bench-scale flow loop. Adding PCM to water increases the thermal capacity of the heat transfer fluid and therefore decreases the volume that needs to be pumped in a district cooling system. It also increases the heat transfer rate, resulting in smaller heat exchangers. Research is continuing on these fluids in order to determine their behavior in large-size loops and to arrive at optimum formulations.

  11. 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.

  12. 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)

  13. 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)

  14. 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)

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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)

  4. Phasing of Debuncher Stochastic Cooling Transverse Systems

    SciTech Connect

    Pasquinelli, Ralph

    2000-03-09

    With the higher frequency of the cooling systems in the Debuncher, a modified method of making transfer functions has been developed for transverse systems. (Measuring of the momentum systems is unchanged.) Speed in making the measurements is critical, as the beam tends to decelerate due to vacuum lifetime. In the 4-8 GHz band, the harmonics in the Debuncher are 6,700 to 13,400 times the revolution frequency. Every Hertz change in revolution frequency is multiplied by this harmonic number and becomes a frequency measurement error, which is an appreciable percent of the momentum width of the beam. It was originally thought that a momentum cooling system would be phased first so that the beam could be kept from drifting in revolution frequency. As it turned out, the momentum cooling was so effective (even with the gain turned down) that the momentum width normalized to fo became less than one Hertz on the Schottky pickup. A beam this narrow requires very precise measurement of tune and revolution frequency. It was difficult to get repeatable results. For initial measuring of the transverse arrays, relative phase and delay is all that is required, so the measurement settings outlined below will suffice. Once all input and output arrays are phased, a more precise measurement of all pickups to all kickers can be done with more points and both upper and lower side bands, as in figure 1. Settings on the network analyzer were adjusted for maximum measurement speed. Data is not analyzed until a complete set of measurements is taken. Start and stop frequencies should be chosen to be just slightly wider than the band being measured. For transverse systems, select betatron USB for the measurement type. This will make the measurement two times faster. Select 101 for the number of points, sweep time of 5 seconds, IF bandwidth 30 Hz, averages = 1. It is important during the phasing to continually measure the revolution frequency and beam width of the beam for transverse systems. Beam width is defined as the 3 dB bandwidth of the momentum Schottky divided by 127 (the harmonic of the Schottky pickup in the Debuncher.) Every three to five minutes, the beam drifts enough to make a significant change in the data. Knowing the revolution frequency and beam width to 0.5 Hz is important. If the beam width exceeds 10 Hz, the quality of the measurement will be impaired. Large beam widths can be caused by excessive forward proton beam current. There are also signs that the front-end amplifiers saturate with beam currents above several hundred microamps. The cooling systems were designed to be very sensitive, (that's why the front end is at liquid helium temperature) so a hundred microamps will go a long way. It should be possible to phase the systems with Pbars as a signal to noise ratio of 30 dB was observed with 100 microamps of beam current.

  5. ADMX Phase II : Relocation and Millikelvin Cooling

    SciTech Connect

    Heilman, Jesse; Tracy, Kyle

    2010-08-30

    Low mass axions are an attractive candidate for making up dark matter. While there are several models for how the Axion couples with other matter, were they to be the majority of the local galactic dark matter halo, they would have a number density on the order of 10{sup 14} cm{sup -3}. The Axion Dark Matter eXperiment (ADMX) is a microwave cavity experiment searching for axion Dark Matter via the axion's electromagnetic coupling. While the original ADMX did not see evidence of axions, the experiment is planned to go through two phases of upgrades to expand its sensitivity and provide a definitive search for axion dark matter. The first phase established the use of a SQUID amplifier which can reduce the amplifier noise temperature to the 100 mK range. In the second phase we will first move the experiment from LLNL to CENPA at the University of Washington. Once the experiment has been moved successfully we will install a dilution refrigerator to cool the cavity to the 100 mK range thus increasing the sensititivity to the level required to scan the remainder of the allowed model space.

  6. Advanced heat pump cycle for district heating and cooling systems

    SciTech Connect

    Radermacher, R.

    1991-07-01

    A bread board heat pump was designed and built to test the performance of a vapor compression heat pump with two stage ammonia-water solution circuits. The design was updated based on the experience gained with the single stage version of this heat pump. A major improvement was obtained by eliminating the rectifier. The new scheme was first investigated by computer simulation and then incorporated in the experimental setup. Water balance in the high and low temperature circuits is now maintained by bleeding up to 2.5% of the weak solution flow from one solution circuit to the other. The advantages of this scheme are reduced first cost, simplified design and control, 20--30% improvement in cooling coefficient of performance and 10--15% increase in cooling capacity as compared to the cycle with a rectifier. Coefficients of performance in the range of 0.84 to 1.03 were obtained experimentally for a temperature lift of 100-K. The pressure ratios encountered were in the range of 7.6 to 9.9, which are 35 to 50% of the pressure ratio expected for a conventional heat pump. Thus the results demonstrate that high temperature lifts can be achieved at pressure ratios which are less than half as large as for conventional systems. The cooling capacities were in the range of 2.79 to 4.21 kW. 13 refs., 5 figs., 2 tabs.

  7. The road to Lockport: Historical background of district heating and cooling

    SciTech Connect

    Pierce, M.A.

    1995-08-01

    The idea of district heating can be traced back to Roman hypocausts, some of which warmed multiple buildings. They were reintroduced into Europe during the Renaissance and slowly evolved into modern hot air, hot water, and steam heating systems. Major heating milestones are summarized, along with requirements to conserve fuel and abate smoke. Early district-heating proposals in London (1623 and 1820s), Pennsylvania (1869), Warsaw and Zuerich (1872) are discussed, as are steam systems actually installed at the US Naval Academy (1853), the Philadelphia Centennial Exposition, and a hot water cogeneration system at the Banstead Downs Asylum in England (1876). Birdsill Holly--a Lockport, New York, inventor--installed the first successful commercial district heating system there in 1877. By 1890, more than 50 were installed, many of which are still operating today. District cooling began shortly after that, with successful introduction of systems using brine and ammonia.

  8. 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.

  9. A novel concept for heat transfer fluids used in district cooling systems. Progress report, September 25, 1990--December 31, 1990

    SciTech Connect

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

    1991-01-04

    Low-temperature phase-change materials (PCMS) were mixed with water to enhance the performance of heat transfer fluid. Several PCMs were tested in a laboratory-scale test loop to check their suitability to district cooling applications. The phase-change temperatures and latent heats of fusion of tetradecane, pentadecane, and hexadecane paraffin waxes were measured using a differential scanning calorimeter. 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. For 10% and 25% PCM-water slurries, the heat transfer enhancement was found to be approximately 18 and 30 percent over the value of water, respectively. It was also found that, in the turbulent region, there is only a minor pumping penalty from the addition of up to 25% PCM to the water. It was demonstrated that pentadecane does not clog in a glass-tube chiller, and continuous pumping below its freezing, point (9.9{degrees}C):was successfully carried out in a bench-scale flow loop. Adding PCM to water increases the thermal capacity of the heat transfer fluid and therefore decreases the volume that needs to be pumped in a district cooling system. It also increases the heat transfer rate, resulting in smaller heat exchangers. Research is continuing on these fluids in order to determine their behavior in large-size loops and to arrive at optimum formulations.

  10. 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.

  11. 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)

  12. Energy and economic implications of combining district cooling with thermal storage

    SciTech Connect

    Andrepont, J.S.; Kooy, R.J.; Winters, P.J.

    1995-12-31

    This paper presents an overview of the energy efficiency, environmental impact, and economics for combining Thermal Energy Storage (TES) technology alternatives with various chilling technology options for District Energy applications. Technical material from diverse, recent conferences and studies are cited and reviewed. Source energy efficiency and emissions (at electric utility power plants) as well as site energy efficiency (where chilling is produced and used) are examined. Economics for both capital and O&M costs are reviewed from actual District Cooling case studies. The TES technology alternatives evaluated are chilled water and ice storage (as well as non-TES base cases), including options for low temperature air production and ice slurry distribution. Chilling technology options which are considered include electric motor-driven, steam turbine-driven, and gas turbine-driven compressors, steam or gas absorption, and {open_quotes}free-cooling{close_quotes}. Additional synergies are demonstrated between TES and cogeneration, another technology which is often coupled with District Energy. Chilled Water TES is found to be particularly advantageous for District Energy applications, in terms of energy efficiency, powerplant emissions, and capital & operating economics.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. Defect Formation in Quench-Cooled Superfluid Phase Transition

    NASA Astrophysics Data System (ADS)

    Ruutu, V. M.; Eltsov, V. B.; Krusius, M.; Makhlin, Yu. G.; Plaais, B.; Volovik, G. E.

    1998-02-01

    We use neutron absorption in rotating 3He-B to heat locally a ~100-?m-size volume into normal phase. When the heated region cools back in microseconds, vortex lines are formed. We record with NMR the number of lines vs the applied superflow velocity and compare to the Kibble-Zurek theory of vortex-loop freeze-out from a random network of defects. The measurements confirm the calculated loop-size distribution and indicate that the superfluid state itself forms as a patchwork of competing A- and B-phase blobs. The consequences to the A-->B transition in supercooled 3He-A are discussed.

  18. 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.

  19. 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.

  20. 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.

  1. [Isolation of Legionella spp. from cooling tower water in Kinki District, Japan].

    PubMed

    Koide, M; Kamino, T; Tsukahara, Y; Maejima, K; Saitoh, A

    1991-12-01

    Distribution of Legionella spp. were surveyed two different times in Kinki District, Japan. The first time, eighty six building cooling tower waters were collected from Osaka, Hyogo and Nara Prefecture between April and December, 1987. The second time, thirty five waters were studied from Nishinomiya City in Hyogo Prefecture on July, 1989. BMPA alpha agar plate was used as the isolation medium for the first eighty six samples and MWY agar plate for the second thirty five samples. Legionella were isolated from forty two samples (48.8%) of the first eighty six samples. Three different species of Legionella were isolated simultaneously from one sample and two species from eight samples. L. pneumophila serogroup 1 was the most predominant species. Twenty three samples (65.7%) were positive in culture from the second thirty five samples. Three different species of Legionella were isolated simultaneously from three samples and two species from eleven samples. Legionella anisa was more predominant than L. pneumophila serogroup 1 in this study. PMID:1783809

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. Brazing of the Tore Supra actively cooled Phase III Limiter

    SciTech Connect

    Nygren, R.E.; Walker, C.A.; Lutz, T.J.; Hosking, F.M.; McGrath, R.T.

    1993-12-31

    The head of the water-cooled Tore Supra Phase 3 Limiter is a bank of 14 round OFHC copper tubes, curved to fit the plasma radius, onto which several hundred pyrolytic graphite (PG) tiles and a lesser number of carbon fiber composite tiles are brazed. The small allowable tolerances for fitting the tiles to the tubes and mating of compound curvatures made the brazing and fabrication extremely challenging. The paper describes the fabrication process with emphasis on the procedure for brazing. In the fixturing for vacuum furnace brazing, the tiles were each independently clamped to the tube with an elaborate set of window frame clamps. Braze quality was evaluated with transient heating tests. Some rebrazing was necessary.

  7. 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.

  8. 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.

  9. 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.

  10. Geothermal district heating systems

    NASA Astrophysics Data System (ADS)

    Budney, G. S.; Childs, F.

    1982-06-01

    Ten district heating demonstration projects and their present status are described. The projects are Klamath County YMCA, Susanville District Heating, Klamath Falls District Heating, Reno Salem Plaza Condominium, El Centro Community Center Heating/Cooling, Haakon School and Business District Heating, St. Mary's Hospital, Diamond Ring Ranch, Pagosa Springs District Heating, and Boise District Heating.

  11. Geothermal district heating systems

    SciTech Connect

    Budney, G.S.; Childs, F.

    1982-01-01

    Ten district heating demonstration projects and their present status are described. The projects are Klamath County YMCA, Susanville District Heating, Klamath Falls District Heating, Reno Salem Plaza Condominium, El Centro Community Center Heating/Cooling, Haakon School and Business District Heating, St. Mary's Hospital, Diamond Ring Ranch, Pagosa Springs District Heating, and Boise District Heating.

  12. Advanced heat pump cycle for district heating and cooling systems. Second quarterly progress report

    SciTech Connect

    Radermacher, R.

    1991-10-01

    A new scheme to significantly improve the performance of the two stage vapor compression cycle by eliminating the rectifier was first investigated with the help of computer simulation, and then incorporated in the experimental setup. Simulation results show that the cycle with a bleed line (modified cycle without the rectifier) has 20 to 30% higher cooling COP as compared to the cycle with the rectifier. It is important to note that this improvement in COP is accompanied by 10 to 15% increase in cooling load. Initial experimental results along with operating experience and description of the data acquisition program are presented here. Results show that hear can be pumped from an average temperature of 0{degrees}C to an average temperature of 100{degrees}C with a pressure ratio as low as 7.1. Cooling COPs up to 1.0 were obtained for cooling loads of about 4.17 kW.

  13. 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.

  14. District heating/cooling feasibility, City of Devils Lake, North Dakota. Final report, 1981-1982

    SciTech Connect

    Moen, C.; Zaiser, S.L.

    1982-11-01

    The City of Devils Lake took over the operation of a district heating system originally built and operated by the Otter Tail Power Company. This was a steam system with heat supplied with cogeneration from the production of electricity. The system was small, but the engineering was good, it used a two pipe, return condensate system. It was originally designed to burn coal as fuel, it was later converted to oil, and then to natural gas. Most of the business district, a number of institutions, and public housing buildings were carried by the district heating system. The search for less expensive fuel included solid waste, but the amount was insufficient to carry through the cold winters. Agricultural waste in the form of durum wheat straw is available in abundance. Tests have shown that pound for pound the straw had a higher BTU content than local coal. Contracts have been made with local farmers to deliver straw bales or rolls at prices attractive to both parties. The system is now operating.

  15. 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.

  16. Development and evaluation of an advisory system for optimal operation of a district heating and cooling plant

    SciTech Connect

    Yokoyama, Ryohe; Ito, Koichi; Kamimura, Kazuyuki; Miyasaka, Fusachika

    1999-07-01

    A computer-aided advisory system for assisting operators in real-time optimal operation of a district heating and cooling plant is developed and evaluated. An autoregressive integrated moving average model is used to predict energy demands, An optimal operational planning method based on the dynamic, mixed-integer, and linear programming is used to conduct unit commitment. To evaluate the validity and effectiveness of the system, a numerical study is carried out using energy demands predicted and measured throughout a year for an existing plant. Through the study, the relationship between energy demand prediction and unit commitment is clarified. Especially, the trade-off relationship between the increase in operational cost and the deficit in energy supply is clarified in relation to the uncertainty in energy demands.

  17. Study of Microsegregation and Laves Phase in INCONEL718 Superalloy Regarding Cooling Rate During Solidification

    NASA Astrophysics Data System (ADS)

    Ling, Lishibao; Han, Yanfeng; Zhou, Wei; Gao, Haiyan; Shu, Da; Wang, Jun; Kang, Maodong; Sun, Baode

    2015-01-01

    Cooling rate is an important and controllable variable in casting processing. The effect of cooling rate on the microsegregation and Laves phase in INCONEL718 superalloy castings was studied by high-temperature-laser confocal scanning microscopy and quantitative metallography in this study. The transformation rate of solid phase with a feature of Gaussian distribution in the solidifications at the cooling rates of 0.10 to 14 K/s is acquired. The solidification time and secondary dendrite arm spacing (SDAS) as a function of cooling rate are analyzed. The amount of Laves phase presents a maximum value at a threshold cooling rate of 3 K/s owing to the opposite effects of cooling rate on the solidification time and SDAS. A modified dimensionless microsegregation index criterion was used for the scaling of solute segregation and Laves phase depending on cooling rates. The prediction of maximal microsegregation and the amount of Laves phase by MSI and experiments provide a guide for cooling rate control in the casting applications.

  18. 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.

  19. 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.

  20. 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.

  1. 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%.

  2. 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%.

  3. 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.

  4. High capacity mechanical water-vapor compression vacuum ice machines for district cooling and heating

    SciTech Connect

    Elovic, P.; Holmes, B.

    1995-12-31

    The theoretical advantages of the refrigeration cycle using the vacuum ice cooling process based on a water vapor refrigerant cycle are well known and have already been demonstrated in various small scale applications. The advantages include: low energy consumption, reduced capital investment in heat exchangers and coolant piping systems, and lower overall operating and maintenance costs. However, the commercial development of large scale water vapor refrigerant systems for the production of pumpable ice slurries have heretofore been hampered by the limitations of the available compressor technology and by problems associated with the transportability of ice slurries. These factors led to the development and installation of a 3 MW(ref) vacuum ice machine in South Africa - the first of its kind - for application in the cooling of deep level gold mines. The process developed uses direct contact heat transfer in evaporation and condensation with water vapor as the sole refrigerant. The system employs a unique two stage centrifugal compressor system designed and developed specifically for large flow rates and high compression ratios. The vacuum compressor technology is an extension of existing technology based on the results of thirty years of development evolution in commercial seawater desalination systems. The present paper describes the technical characteristics of the machine recently developed for the above application and the equipment used to produce and transport concentrated ice slurries. The commercial use of the water vapor compression cycle for cooling or heating systems and for various potential industrial applications are described as well.

  5. High capacity mechanical water - vapor compression vacuum ice machines for district cooling and heating

    SciTech Connect

    Elovic, P.; Holmes, B.

    1996-11-01

    The theoretical advantages of the refrigeration cycle using the vacuum ice cooling process based on a water vapor refrigerant cycle are well known and have already been demonstrated in various small scale applications. The advantages include: low energy consumption, reduced capital investment in heat exchangers and coolant piping systems, and lower overall operating and maintenance costs. However, the commercial development of large scale water vapor refrigerant systems for the production of pumpable ice slurries have heretofore been hampered by the limitations of the available compressor technology and by problems associated with the transportability of ice slurries. These factors led to the development and installation of a 3 MW(ref) vacuum ice machine in South Africa - the first of its kind - for application in the cooling of deep level gold mines. The process developed uses direct contact heat transfer in evaporation and condensation with water vapor as the sole refrigerant. The system employs a unique two stage centrifugal compressor system designed and developed specifically for large flow rates and high compression ratios. The vacuum compressor technology is an extension of existing technology based on the results of thirty years of development evolution in commercial seawater desalination systems. The present paper describes the technical characteristics of the machine recently developed for the above application and the equipment used to produce and transport concentrated ice slurries. The commercial use of the water vapor compression cycle for cooling or heating systems and for various potential industrial applications are described as well.

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

    NASA Astrophysics Data System (ADS)

    Rusowicz, Artur; Leszczy?ski, Maciej; Grzebielec, Andrzej; Laskowski, Rafa?

    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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. Asymmetric oscillations during phase separation under continuous cooling: A simple model

    NASA Astrophysics Data System (ADS)

    Hayase, Yumino; Kobayashi, Mika; Vollmer, Doris; Pleiner, Harald; Auernhammer, Gnter K.

    2008-11-01

    We investigate the phase separation of binary mixtures under continuous cooling using the Cahn-Hilliard equation including the effect of gravity. In our simple model, sedimentation is accounted for by instantaneously "removing" droplets from the supersaturated mixture into the coexisting phase once the droplets have reached a defined maximum size. Our model predicts an oscillatory variation of turbidity. Depending on the composition, either both phases oscillate (symmetric oscillations) or only one of the phases oscillates (asymmetric oscillations). In the asymmetric case, droplet sedimentation from the majority phase into the minority phase reduces supersaturation in the minority phase. This inhibits droplet formation in the minority phase. The cooling rate dependence of the period agrees with experimental results.

  12. Computer cooling using a two phase minichannel thermosyphon loop heated from horizontal and vertical sides and cooled from vertical side

    NASA Astrophysics Data System (ADS)

    Bieli?ski, Henryk; Mikielewicz, Jaros?aw

    2010-10-01

    In the present paper it is proposed to consider the computer cooling capacity using the thermosyphon loop. A closed thermosyphon loop consists of combined two heaters and a cooler connected to each other by tubes. The first heater may be a CPU processor located on the motherboard of the personal computer. The second heater may be a chip of a graphic card placed perpendicular to the motherboard of personal computer. The cooler can be placed above the heaters on the computer chassis. The thermosyphon cooling system on the use of computer can be modeled using the rectangular thermosyphon loop with minichannels heated at the bottom horizontal side and the bottom vertical side and cooled at the upper vertical side. The riser and a downcomer connect these parts. A one-dimensional model of two-phase flow and heat transfer in a closed thermosyphon loop is based on mass, momentum, and energy balances in the evaporators, rising tube, condenser and the falling tube. The separate two-phase flow model is used in calculations. A numerical investigation for the analysis of the mass flux rate and heat transfer coefficient in the steady state has been accomplished.

  13. 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

  14. 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

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. 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.

  4. 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%.

  5. Community oriented primary care in Tshwane District, South Africa: Assessing the first phase of implementation

    PubMed Central

    Marcus, Tessa; Memon, Shehla; Bam, Nomonde; Hugo, Jannie

    2013-01-01

    Abstract Background Re-engineering primary health care is a cornerstone of the health sector reform initiated nationally in South Africa in 2009. Using the concept of ward based NGO-run health posts, Tshwane District, Gauteng, began implementing community oriented primary care (COPC) through ward based outreach teams (WBOT) in seven wards during 2011. Objectives This study sought to gain insight into how primary health care providers understood and perceived the first phase of implementing COPC in the Tshwane district. Method Qualitative research was performed through focus group interviews with staff of the seven health posts during September 2011 and October 2011. It explored primary health care providers understanding, perception and experience of COPC. Results Participants raised organisational, workplace and community relationship issues in the discussions. Organisationally, these related to the process of initiating and setting up COPC and the relationship between governmental and nongovernmental organisations. Issues that arose around the workplace related to the job situation and employment status and remuneration of health post staff. Community related issues centred on the role and relationship between service providers and their communities. Conclusion COPC touched a responsive nerve in the health care system, both nationally and locally. It was seen as an effective way to respond to South Africa's crisis of health care. Initiating the reform was inevitably a complex process. In this initial phase of implementing COPC the political commitment of governmental and nongovernmental organisations was evident. What still had to be worked through was how the collaboration would materialise in practice on the ground.

  6. Modeling of phase transformation behavior in hot-deformed and continuously cooled C-Mn steels

    SciTech Connect

    Liu, Z.; Wang, G.; Gao, W.

    1996-08-01

    Computer models of phase transformation from austenite to ferrite, austenite to pearlite, and austenite to bainite in hot-deformed carbon-manganese steels during continuous cooling were established on the basis of Cahn`s transformation theory, thermal-dilatometric experiments, and thermodynamic calculations. These models showed good agreement with results measured from pilot hot rolling experiments.

  7. 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.

  8. Supercritical supersaturations and ultrafast cooling of the growth solution in liquid-phase epitaxy of semiconductors

    NASA Astrophysics Data System (ADS)

    Abramov, A. V.; Deryagin, N. G.; Tret'yakov, D. N.

    1996-04-01

    A method for accomplishing ultrafast cooling is proposed which makes possible supercritical supersaturations of the growth solution in liquid-phase epitaxy. Growth boat designs providing cooling rates as high as 0268-1242/11/4/025/img1 are considered. The temperatures of contact, 0268-1242/11/4/025/img2, of a GaAs substrate with a Ga-based solution and of a Si substrate with a Sn-based growth solution, calculated for various substrate 0268-1242/11/4/025/img3 and solution temperatures 0268-1242/11/4/025/img4, are in good agreement with experimental values. The maximum attainable supercooling is markedly increased to as high as 0268-1242/11/4/025/img5 for the Ga - As system, when the growth solution is subjected to ultrafast cooling. The prospects of using the method for fabricating heterostructures with a large lattice mismatch are discussed.

  9. Transformation behavior of the ?U(Zr,Nb) phase under continuous cooling conditions

    NASA Astrophysics Data System (ADS)

    Komar Varela, C. L.; Gribaudo, L. M.; Gonzlez, R. O.; Aric, 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 ?U(Zr,Nb) phase during the whole fabrication process. Therefore, it is necessary to define a range of concentrations in which the ?U(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 ?U(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 ?U(Zr,Nb) phase. In experiments that involve higher cooling conditions, it has been determined that this concentration can be halved.

  10. 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.

  11. 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

  12. 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

  13. 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…

  14. 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 200C) 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

  15. 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.

  16. 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.

  17. Heat-Transfer Measurements in the Primary Cooling Phase of the Direct-Chill Casting Process

    NASA Astrophysics Data System (ADS)

    Caron, Etienne J. F. R.; Baserinia, Amir R.; Ng, Harry; Wells, Mary A.; Weckman, David C.

    2012-10-01

    Thermal modeling of the direct-chill casting process requires accurate knowledge of (1) the different boundary conditions in the primary mold and secondary direct water-spray cooling regimes and (2) their variability with respect to process parameters. In this study, heat transfer in the primary cooling zone was investigated by using temperature measurements made with subsurface thermocouples in the mold as input to an inverse heat conduction algorithm. Laboratory-scale experiments were performed to investigate the primary cooling of AA3003 and AA4045 aluminum alloy ingots cast at speeds ranging between 1.58 and 2.10 mm/s. The average heat flux values were calculated for the steady-state phase of the casting process, and an effective heat-transfer coefficient for the global primary cooling process was derived that included convection at the mold surfaces and conduction through the mold wall. Effective heat-transfer coefficients were evaluated at different points along the mold height and compared with values from a previously derived computational fluid dynamics model of the direct-chill casting process that were based on predictions of the air gap thickness between the mold and ingot. The current experimental results closely matched the values previously predicted by the air gap models. The effective heat-transfer coefficient for primary cooling was also found to increase slightly with the casting speed and was higher near the mold top (up to 824 W/m2K) where the molten aluminum first comes in contact with the mold than near the bottom (as low as 242 W/m2K) where an air gap forms between the ingot and mold because of thermal contraction of the ingot. These results are consistent with previous studies.

  18. 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

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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

  5. Influence of Strain History and Cooling Rate on the Austenite Decomposition Behavior and Phase Transformation Products in a Microalloyed Steel

    NASA Astrophysics Data System (ADS)

    Sun, L.; Muszka, K.; Wynne, B. P.; Palmiere, E. J.

    2014-07-01

    The effect of simple strain path changes as well as post-deformation continuous cooling rate during thermomechanical-controlled processing of microalloyed steel was studied using laboratory physical simulation. The phase transformation characteristics were directly analyzed by dilatometry under various cooling rates. The microstructures of the transformation products were characterized quantitatively using EBSD. The results have shown that while strain path changes impose a considerable influence on the hot flow behavior of the austenite, the cooling rate following hot deformation is the determining factor of the phase transformation mechanism and behavior which establishes the final transformation products and subsequent mechanical properties.

  6. 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 85C.

  7. 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 (CV?, CV??, CV??, and CV??) 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 CV? and CV?? vests provided cooling during exercise (40 and 29 W, respectively), whereas all CVs provided cooling during resting recovery (CV? 69 W, CV?? 66 W, CV?? 55 W and CV?? 29 W) (P < 0.05). In all conditions, skin blood flow increased when exercising and reduced during recovery, but was lower in the CV? and CV?? 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 CV?? to the CV?, 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 (CV?) may also be appropriate if more insulation was worn between the cooling packs and the skin than used in this study. PMID:23160652

  8. A study of the cool gas in the Large Magellanic Cloud. I. Properties of the cool atomic phase - a third H i absorption survey

    NASA Astrophysics Data System (ADS)

    Marx-Zimmer, M.; Herbstmeier, U.; Dickey, J. M.; Zimmer, F.; Staveley-Smith, L.; Mebold, U.

    2000-02-01

    The cool atomic interstellar medium of the Large Magellanic Cloud (LMC) seems to be quite different from that in the Milky Way. In a series of three papers we study the properties of the cool atomic hydrogen in the LMC (Paper I), its relation to molecular clouds using SEST-CO-observations (Paper II) and the cooling mechanism of the atomic gas based on ISO-[\\CII]-investigations (Paper III). In this paper we present the results of a third 21 cm absorption line survey toward the LMC carried out with the Australia Telescope Compact Array (ATCA). 20 compact continuum sources, which are mainly in the direction of the supergiant shell LMC 4, toward the surroundings of 30 Doradus and toward the eastern steep \\HI\\ boundary, have been chosen from the 1.4 GHz snapshot continuum survey of Marx et al. We have identified 20 absorption features toward nine of the 20 sources. The properties of the cool \\HI\\ clouds are investigated and are compared for the different regions of the LMC taking the results of Dickey et al. (survey 2) into account. We find that the cool \\HI\\ gas in the LMC is either unusually abundant compared to the cool atomic phase of the Milky Way or the gas is clearly colder (\\Tc\\ ~ 30 K) than that in our Galaxy (\\Tc\\ ~ 60 K). The properties of atomic clouds toward 30 Doradus and LMC 4 suggest a higher cooling rate in these regions compared to other parts of the LMC, probably due to an enhanced pressure near the shock fronts of LMC 4 and 30 Doradus. The detected cool atomic gas toward the eastern steep \\HI\\ boundary might be the result of a high compression of gas at the leading edge. The Australia Telescope is funded by the Commonwealth of Australia for operation as a National Facility managed by CSIRO.

  9. 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.

  10. Cold fiber solid-phase microextraction device based on thermoelectric cooling of metal fiber.

    PubMed

    Haddadi, Shokouh Hosseinzadeh; Pawliszyn, Janusz

    2009-04-01

    A new cold fiber solid-phase microextraction device was designed and constructed based on thermoelectric cooling. A three-stage thermoelectric cooler (TEC) was used for cooling a copper rod coated with a poly(dimethylsiloxane) (PDMS) hollow fiber, which served as the solid-phase microextraction (SPME) fiber. The copper rod was mounted on a commercial SPME plunger and exposed to the cold surface of the TEC, which was enclosed in a small aluminum box. A heat sink and a fan were used to dissipate the generated heat at the hot side of the TEC. By applying an appropriate dc voltage to the TEC, the upper part of the copper rod, which was in contact to the cold side of the TEC, was cooled and the hollow fiber reached a lower temperature through heat transfer. A thermocouple was embedded in the cold side of the TEC for indirect measurement of the fiber temperature. The device was applied in quantitative analysis of off-flavors in a rice sample. Hexanal, nonanal, and undecanal were chosen as three off-flavors in rice. They were identified according to their retention times and analyzed by GC-flame ionization detection instrument. Headspace extraction conditions (i.e., temperature and time) were optimized. Standard addition calibration graphs were obtained at the optimized conditions and the concentrations of the three analytes were calculated. The concentration of hexanal was also measured using a conventional solvent extraction method (697+/-143ng/g) which was comparable to that obtained from the cold fiber SPME method (644+/-8). Moreover, the cold fiber SPME resulted in better reproducibility and shorter analysis time. Cold fiber SPME with TEC device can also be used as a portable device for field sampling. PMID:18814881

  11. Compact storage of heat and coolness by phase change materials while preventing stratification

    SciTech Connect

    MacCracken, C.D.

    1983-09-13

    While many materials and additives which will melt and freeze at various temperature levels for storing and releasing large amounts of heat thereby per unit volume have been disclosed, the packaging of these materials with suitable non-corrodible long-lasting heat exchange structures has been cumbersome and expensive. The present invention provides an inexpensive, high performance, non-corrodible thermal storage method and system adapted for use with heat storage materials of various compositions and adapted for use over a wide range of temperatures, including a heat exchanger which provides for phase change to occur approximately simultaneously throughout the volume of the entire storage mass and provides for the sites at which the phase change is occurring to be approximately uniformly distributed throughout the volume of the heat storage material. Problems of thermal expansion, stratification and sub-cooling are eliminated. Thermal storage methods and systems embodying the present system may advantageously be used for off-peak storage of electric refrigeration, cooling and heating as well as solar heating and other applications.

  12. 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, 34C, 75% RH) and hot dry (HD, 34C, 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

  13. 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.

  14. 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.

  15. 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.

  16. 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 patterns 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 dies 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.

  17. 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.

  18. 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.

  19. High Resolution Infrared Spectroscopy of Jet-Cooled Phenyl Radical in the Gas Phase

    NASA Astrophysics Data System (ADS)

    Sharp-Williams, Erin N.; Roberts, Melanie A.; Nesbitt, David J.

    2009-06-01

    Phenyl radical (C_6H_5) is one of the most important reactive intermediates, as it is formed from the homolytic cleavage of a CH bond in benzene (C_6H_6), and hence it plays a central role in the combustion of fossil fuels that are typically rich in aromatics. We recently recorded the first high resolution infrared spectra of jet-cooled phenyl radical in the gas phase. This was obtained by direct absorption laser spectroscopy in a slit-jet discharge supersonic expansion of a phenyl halide precursor (C_6H_5X, i.e. C_6H_5I and C_6H_5Br) diluted in a Neon/Helium gas mixture. We observed an A-type band, which arises from a fundamental excitation of the out-of-phase symmetric CH stretch (?_{19}). The unambiguous assignment of the rotational structure in this band to C_6H_5 is facilitated by comparing 2-line combination differences with the Fourier transform microwave (FTM) and direct absorption millimeter-wave (mm-wave) measurements of the ground state by McMahon et al. A least-squares fit to an asymmetric top Hamiltonian of the rotationally-resolved vibrational band is done to determine upper-state rotational constants and a gas-phase band origin (?_0) of 3071.8904 (10) cm^{-1}. This is in very good agreement with the value of 3071 cm^{-1} for the out-of-phase symmetric CH stretch of phenyl reported by Friderichsen et al. from matrix isolation studies, which indicates a surprisingly small red shift due to the low-temperature argon environment. R. J. McMahon, M. C. McCarthy, C. A. Gottlieb, J. B. Dudek, J. F. Stanton and P. Thaddeus, Ap. J. 590, L61 (2003). A. V. Friderichsen, J. G. Radziszewski, M. R. Nimlos, P. R. Winter, D. C. Dayton, D. E. David and G. B. Ellison, J. Am. Chem. Soc. 123, 1977 (2001).

  20. 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.

  1. 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.

  2. 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

  3. 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…

  4. Thermal characteristics of two phase thermosyphon cooling module for multi-chip device

    SciTech Connect

    Choi, S.B.; Nam, S.S.; Kim, J.H.; Kwak, H.Y.

    1996-12-31

    A thermosyphonic cooling module (TSCM) has been designed, fabricated and tested to cool the multi-chip plugged into a planar packaging system. The cooling module consists of a cold plate and an integrated condenser. With an allowable temperature rise of 56 C on the surface of the heater, the cooling module TSCM can handle a heat flux about 2.7 W/cm{sup 2}. The transient characteristics of the cooling module have proved to be excellent; that is, when a heat load is applied to the system, steady state can be achieved within 10--15 minutes. It has been found that the length of the vapor channel between the cold plate and the condenser and ambient as well as the condenser temperatures affect the system performance.

  5. UV photodissociation spectroscopy of cryogenically cooled gas phase host-guest complex ions of crown ethers.

    PubMed

    Inokuchi, Yoshiya; Haino, Takeharu; Sekiya, Ryo; Morishima, Fumiya; Dedonder, Claude; Fraud, Graldine; Jouvet, Christophe; Ebata, Takayuki

    2015-10-21

    The geometric and electronic structures of cold host-guest complex ions of crown ethers (CEs) in the gas phase have been investigated by ultraviolet (UV) fragmentation spectroscopy. As host CEs, we chose 15-crown-5 (15C5), 18-crown-6 (18C6), 24-crown-8 (24C8), and dibenzo-24-crown-8 (DB24C8), and as guests protonated-aniline (anilineH(+)) and protonated-dibenzylamine (dBAMH(+)) were chosen. The ions generated by an electrospray ionization (ESI) source were cooled in a quadrupole ion-trap (QIT) using a cryogenic cooler, and UV spectra were obtained by UV photodissociation (UVPD) spectroscopy. UV spectroscopy was complemented by quantum chemical calculations of the most probable complex structures. The UV spectrum of anilineH(+)CEs is very sensitive to the symmetry of CEs; anilineH(+)18C6 shows a sharp electronic spectrum similar to anilineH(+), while anilineH(+)15C5 shows a very broad structure with poor Franck-Condon factors. In addition, a remarkable cage effect in the fragmentation process after UV excitation was observed in both complex ions. In anilineH(+)CE complexes, the cage effect completely removed the dissociation channels of the anilineH(+) moiety. A large difference in the fragmentation yield between dBAMH(+)18C6 and dBAMH(+)24C8 was observed due to a large barrier for releasing dBAMH(+) from the axis of rotaxane in the latter complex. PMID:26095662

  6. 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…

  7. 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.

  8. Evolution of vacuum states and phase transitions in the two Higgs doublet model during cooling of the Universe

    NASA Astrophysics Data System (ADS)

    Ginzburg, I. F.; Ivanov, I. P.; Kanishev, K. A.

    2010-04-01

    We consider the evolution of the ground state in the two Higgs doublet model during cooling down of the Universe after the big bang. Different regions in the space of free parameters of this model correspond to different sequences of thermal phase transitions. We discuss different paths of thermal evolution and corresponding evolution of physical properties of the system for different modern values of the parameters.

  9. 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

  10. 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

  11. 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.

  12. 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

  13. 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.

  14. 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.

  15. Use of treated gasification wastewater in a pilot cooling tower. Phase I. Final report for the period ending January 31, 1984

    SciTech Connect

    Willson, W.G.; Hendrikson, J.G.; Mann, M.D.; Galegher, S.J.; Gallagher, J.R.; Mayer, G.G.; Thomas, W.C.; Winton, S.L.; Nelson, D.F.

    1984-05-16

    During the UNDERC cooling tower tests, data were colleced and evaluated in five major areas: characterization of cooling tower streams, process performance, biofouling, corrosion, and inorganic/organic fouling. A summary of the results and conclusions for each area is presented. Recommendations are provided for research and development programs to further define the pretreatment and operating requirements for the use of wastewater as cooling tower makeup. The results of the Phase I-Pilot Cooling Tower test have revealed several potential problems that may arise from the use of a relatively high organic content gas liquor as cooling tower makeup. Most of the problems identified are related to the presence of organics in the wastewater which promote biofouling/fouling, corrosion, and emissions from the cooling tower. The Phase II-Pilot Cooling Tower Test will address this issue by identifying the advantages of further treatment of stripped gas liquor to reduce the organic content to a lower level before use in the cooling tower. This test will parallel the Phase I test using the same system and monitoring procedures. Comparison of the results of Phase I and Phase II tests will provide an indication of how well problem areas can be avoided with additional makeup water pretreatment. 39 references, 34 tables, and 25 figures.

  16. Bladder cooling in patients treated with regional hyperthermia of the pelvis using an annular phased array.

    PubMed

    Kapp, D S; Prionas, S D; Fessenden, P; Liu, F F; Lee, E R; Lohrbach, A W

    1988-06-01

    Regional hyperthermia for the treatment of deep seated tumors is often limited by excessive heating of normal tissues, usually with associated patient pain and/or discomfort. The use of bladder cooling via perfusion of distilled water through a modified tri-lumen irrigation catheter as an aid to circumventing this problem in one anatomical region is described. This relatively simple technique provided rapid pain relief and permitted completion of the hyperthermia treatment in a satisfactory manner. Modifications of this technique may permit selective heating and/or cooling of the bladder during regional hyperthermia treatments in the pelvis. PMID:3384729

  17. Variable Gravity Effects on the Cooling Performance of a Single Phase Confined Spray

    NASA Technical Reports Server (NTRS)

    Michalak, Travis; Yerkes, Kirk; Baysinger, Karri; McQuillen, John

    2005-01-01

    The objective of this paper is to discuss the testing of a spray cooling experiment designed to be flown on NASA's KC-135 Reduced Gravity Testing Platform. Spray cooling is an example of a thermal management technique that may be utilized in high flux heat acquisition and high thermal energy transport concepts. Many researchers have investigated the utility of spray cooling for the thermal management of devices generating high heat fluxes. However, there has been little research addressing the physics and ultimate performance of spray cooling in a variable gravity environment. An experimental package, consisting of a spray chamber coupled to a fluid delivery loop system, was fabricated for variable gravity flight tests. The spray chamber contains two opposing nozzles spraying on target Indium Tin Oxide (ITO) heaters. These heaters are mounted on glass pedestals, which are part of a sump system to remove unconstrained liquid from the test chamber. Liquid is collected in the sumps and returned to the fluid delivery loop. Thermocouples mounted in and around the pedestals are used to determine both the heat loss through the underside of the IT0 heater and the heat extracted by the spray. A series of flight tests were carried out aboard the KC-135, utilizing the ability of the aircraft to produce various gravity conditions. During the flight tests, for a fixed flow rate, heat input was varied at 20, 30, 50, and 80W with variable gravities of 0.01, 0.16, 0.36, and 1.8g. Flight test data was compared to terrestrial baseline data in addition to analytical and numerical solutions to evaluate the heat transfer in the heater and support structure . There were significant differences observed in the spray cooling performance as a result of variable gravity conditions and heat inputs. In general, the Nussult number at the heater surface was found to increase with decreasing gravity conditions for heat loads greater than 30W.

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

    PubMed

    Wang, Zhe; Ito, Kanae; Leo, 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

  19. Multi-phase-field modeling of diffusive solid phase transition in carbon steel during continuous cooling transformation

    NASA Astrophysics Data System (ADS)

    Yamanaka, A.; Takaki, T.; Tomita, Y.

    2008-04-01

    The growth kinetics and final morphology of ferrite (?) grains are characterized by interfacial energy and boundary mobility, which strongly correlate to constituent phase, misorientation angle and the specific orientation relationship at the ?/? interface, such as the Kurdjumov-Sachs (KS) orientation relationship. In a previous phase-field simulation of the ? grain growth, interfacial energy and mobility is assumed to be constant. Therefore, the simulated morphology of ? grains is equiaxed. In this study, the multi-phase-field (MPF) simulation of ? grain growth during ??? transformation is performed to study the effects of phase- and misorientation-dependent interfacial energy and boundary mobility on the growth kinetics of ? grains. The phase and misorientation dependence of interfacial energy is simply described by the Read-Shockley equation. Our results indicate that the phase- and misorientation-dependent interfacial energy induces ? grain growth along the ? grain boundary so as to reduce the total interfacial energy of the system. Furthermore, by considering both the phase- and misorientation-dependent interfacial energy and boundary mobility, the plausible growth kinetics of ? grains can be reproduced and the morphology of ? grains can be quite similar to the ? grain morphology determined by the KS orientation relationship.

  20. 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.

  1. 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.

  2. 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

  3. Study of two-phase turbine engine for solar space cooling. Final report

    SciTech Connect

    Amend, W.E.

    1980-08-01

    Detailed mathematical description of two promising Biphase refrigeration cycles were developed and programmed on the computer (all known first-order irreversibilities were accounted for). Extensive parameter sweeps were made to identify the most effective working-fluid combinations and to determine the sensitivity of cycle-performance levels. A Cycle configuration was established for a nominal 3-ton air cooled refrigeration system and the design parameters were determined from the computer code. A series of fluid compatibility tests were run to weed out potential fluid combinations that are reactive.

  4. Spray-roof cooling system-analysis: cooling concept integration, Phase I. Passive and hybrid solar manufactured building project. Project status report No. 1

    SciTech Connect

    Huffman, J. B.; Lindsey, L. L.; Snyder, M. K.

    1981-03-10

    The development of a roof spray system for passive/hybrid building cooling is described. Progress to date in defining and evaluating the issues and constraints relevant to spray roof cooling is described in the context of Butler's passive/hybrid manufactured buildings development program. (MHR)

  5. Gas-phase saturation and evaporative cooling effects during wet compression of a fuel aerosol under RCM conditions

    SciTech Connect

    Goldsborough, S.S.; Johnson, M.V.; Zhu, G.S.; Aggarwal, S.K.

    2011-01-15

    Wet compression of a fuel aerosol has been proposed as a means of creating gas-phase mixtures of involatile diesel-representative fuels and oxidizer + diluent gases for rapid compression machine (RCM) experiments. The use of high concentration aerosols (e.g., {proportional_to}0.1 mL{sub fuel}/L{sub gas}, {proportional_to}1 x 10{sup 9} droplets/L{sub gas} for stoichiometric fuel loading at ambient conditions) can result in droplet-droplet interactions which lead to significant gas-phase fuel saturation and evaporative cooling during the volumetric compression process. In addition, localized stratification (i.e., on the droplet scale) of the fuel vapor and of temperature can lead to non-homogeneous reaction and heat release processes - features which could prevent adequate segregation of the underlying chemical kinetic rates from rates of physical transport. These characteristics are dependent on many factors including physical parameters such as overall fuel loading and initial droplet size relative to the compression rate, as well as fuel and diluent properties such as the boiling curve, vaporization enthalpy, heat capacity, and mass and thermal diffusivities. This study investigates the physical issues, especially fuel saturation and evaporative cooling effects, using a spherically-symmetric, single-droplet wet compression model. n-Dodecane is used as the fuel with the gas containing 21% O{sub 2} and 79% N{sub 2}. An overall compression time and compression ratio of 15.3 ms and 13.4 are used, respectively. It is found that smaller droplets (d{sub 0}{proportional_to} 2-3 {mu}m) are more affected by 'far-field' saturation and cooling effects, while larger droplets (d{sub 0}{proportional_to} 14 {mu}m) result in greater localized stratification of the gas-phase due to the larger diffusion distances for heat and mass transport. Vaporization of larger droplets is more affected by the volumetric compression process since evaporation requires more time to be completed even at the same overall fuel loading. All of the cases explored here yield greater compositional stratification than thermal stratification due to the high Lewis numbers of the fuel-air mixtures (Le{sub g} {proportional_to} 3.8). (author)

  6. 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.

  7. 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.

  8. Integrated natural-gas-engine cooling jacket vapor-compressor program. Annual progress report (phase 2), January-December 1987

    SciTech Connect

    DiBella, F.A.; Becker, F.

    1988-01-01

    A unique, alternative cogeneration system was designed that will provide an industrial or commercial energy user with high-pressure steam and electricity directly from a packaged cogeneration system. The Integrated Gas Engine Vapor Compression System concept includes an engine-generator set and a steam screw compressor that are mechanically integrated with the engine. The gas-fueled engine is ebulliently cooled, thus allowing its water jacket heat to be recovered in the form of low-pressure steam. This steam is then compressed by the steam compressor to a higher pressure, and when combined with the high-pressure steam generated in the engine's exhaust gas boiler it provides the end user with a more useable thermal energy source. Phase 1B of this project was completed in 1986 and consisted primarily of the procurement of equipment and the final design and assembly of a prototype integrated gas-engine vapor-compression system.

  9. Effect of Al2O3 mole fraction and cooling method on vitrification of an artificial hazardous material. Part 1: variation of crystalline phases and slag structures.

    PubMed

    Kuo, Yi-Ming; Huang, Kuo-Lin; Wang, Chih-Ta; Wang, Jian-Wen

    2009-09-30

    This study investigated how Al ions affect slag structure. During vitrification, pure Al(2)O(3), CaO, and SiO(2) served as the encapsulation phases with the use of Al mol% as an operating parameter. All specimens with the same basicity (mass ratio of CaO to SiO(2)) of 2/3 were vitrified at 1400 degrees C and cooled by air cooling or water quenching. XRD was used to measure the volume fractions of crystalline and amorphous phases. In a non-Al environment, CaSiO(3) was formed in air-cooled and water-quenched slags. With the addition of Al(2)O(3), no crystalline phases were observed in water-quenched slags. With the increase of Al mol% in specimens, the Al ions in air-cooled slags initially acted as an intermediate linking one tetrahedron chain to another and reducing the amount of crystalline phase, then behaved as a network former making the slags amorphous, and finally replaced Si ions in silicate frames to generate a large amount of CaAl(2)Si(2)O(8). Air cooling improved the formation of crystallize structures with more leachable metal ions. A highly crystallized Al-framed structure is not suitable for encapsulating hazardous metals in vitrified slags. PMID:19428182

  10. 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.

  11. 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.

  12. Assessing braze quality in the actively cooled Tore Supra Phase III outboard pump limiter

    SciTech Connect

    Nygren, R.E.; Lutz, T.L.; Miller, J.D.; McGrath, R.; Dale, G.

    1994-12-31

    The quality of brazing of pyrolytic graphite armor brazed to copper tubes in Tore Supra`s Phase III Outboard Pump Limiter was assessed through pre-service qualification testing of individual copper/tile assemblies. The evaluation used non-destructive, hot water transient heating tests performed in the high-temperature, high-pressure flow loop at Sandia`s Plasma Materials Test Facility. Surface temperatures of tiles were monitored with an infrared camera as water at 120{degrees}C at about 2.07 MPa (300 psi) passed through a tube assembly initially at 30{degrees}C. For tiles with braze voids or cracks, the surface temperatures tagged behind those of adjacent well-bonded tiles. Temperature tags were correlated with flaw sizes observed during repairs based upon a detailed 2-D heat transfer analyses. {open_quotes}Bad{close_quotes} tiles, i.e., temperature tags of 10-20{degrees}C depending upon tile`s size, were easy to detect and, when removed, revealed braze voids of roughly 50% of the joint area. Eleven of the 14 tubes were rebrazed after bad tiles were detected and removed. Three tubes were rebrazed twice.

  13. 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)

  14. 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.; Atti, 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.

  15. 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)

  16. 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

  17. 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

  18. 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.

  19. 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.

  20. Abundances of volatile-bearing phases in carbonaceous chondrites and cooling rates of meteorites based on cation ordering of orthopyroxenes

    NASA Astrophysics Data System (ADS)

    Ganguly, Jibamitra

    Results of preliminary calculations of volatile abundances in carbonaceous chondrites are discussed. The method (Ganguly 1982) was refined for the calculation of cooling rate on the basis of cation ordering in orthopyroxenes, and it was applied to the derivation of cooling rates of some stony meteorites. Evaluation of cooling rate is important to the analysis of condensation, accretion, and post-accretionary metamorphic histories of meteorites. The method of orthopyroxene speedometry is widely applicable to meteorites and would be very useful in the understanding of the evolutionary histories of carbonaceous chondrites, especially since the conventional metallographic and fission track methods yield widely different results in many cases. Abstracts are given which summarize the major conclusions of the volatile abundance and cooling rate calculations.

  1. Abundances of volatile-bearing phases in carbonaceous chondrites and cooling rates of meteorites based on cation ordering of orthopyroxenes

    NASA Technical Reports Server (NTRS)

    Ganguly, Jibamitra

    1989-01-01

    Results of preliminary calculations of volatile abundances in carbonaceous chondrites are discussed. The method (Ganguly 1982) was refined for the calculation of cooling rate on the basis of cation ordering in orthopyroxenes, and it was applied to the derivation of cooling rates of some stony meteorites. Evaluation of cooling rate is important to the analysis of condensation, accretion, and post-accretionary metamorphic histories of meteorites. The method of orthopyroxene speedometry is widely applicable to meteorites and would be very useful in the understanding of the evolutionary histories of carbonaceous chondrites, especially since the conventional metallographic and fission track methods yield widely different results in many cases. Abstracts are given which summarize the major conclusions of the volatile abundance and cooling rate calculations.

  2. 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.

  3. Microstructure characterization of InAs{sub 0.93}Sb{sub 0.07} films grown by ramp-cooled liquid phase epitaxy

    SciTech Connect

    Deng, H.Y.; Hong, X.K.; Fang, W.Z.; Dai, N. . E-mail: ndai@mail.sitp.ac.cn

    2007-03-15

    InAs{sub 0.93}Sb{sub 0.07} alloy thin films were grown by ramp-cooled liquid phase epitaxy on (100) InAs substrate using horizontally sliding multi-wells graphite boats. The systematic microstructural characterizations of the epi-grown films were analyzed by X-ray diffraction, scanning electronic microscopy and energy dispersive spectra. Four typical surface morphologies of the films were observed, which depend sensitively on growth parameters such as the growth temperature, the substrate etching time, the flux of the hydrogen, and the cooling range and rate. The film shows high crystal perfection with (100) orientation, as evidenced by X-ray measurement. The crystal quality of the epilayer was evaluated by the X-ray double axes diffraction, and the dislocation density was estimated through fitting the (200) and (400) rocking curves by Gaussian lineshape.

  4. Global cooling?

    PubMed

    Damon, P E; Kunen, S M

    1976-08-01

    The world's inhabitants, including Scientists, live primarily in the Northern Hemisphere. It is quite natural to be concerned about events that occur close to home and neglect faraway events. Hence, it is not surprising that so little attention has been given to the Southern Hemisphere. Evidence for global cooling has been based, in large part, on a severe cooling trend at high northern latitudes. This article points out that the Northern Hemisphere cooling trend appears to be out of phase with a warming trend at high latitudes in the Southern Hemisphere. The data are scanty. We cannot be sure that these temperature fluctuations are be not the result of natural causes. How it seems most likely that human activity has already significantly perturbed the atmospheric weather system. The effect of particulate matter pollution should be most severe in the highly populated and industrialized Northern Hemisphere. Because of the rapid diffusion of CO(2) molecules within the atmosphere, both hemispheres will be subject to warming due to the atmospheric (greenhouse) effect as the CO(2) content of the atmosphere builds up from the combustion of fossil fuels. Because of the differential effects of the two major sources of atmospheric pollution, the CO(2) greenhouse effect warming trend should first become evident in the Southern Hemisphere. The socioeconomic and political consequences of climate change are profound. We need an early warning system such as would be provided by a more intensive international world weather watch, particularly at high northern and southern latitudes. PMID:17841800

  5. 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.

  6. 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)

  7. 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, 2CaOFe2O3, and SiO2. SFCA formation (1380 K to 1437 K [1107 C to 1164 C]) was associated with the reaction of CaOFe2O3, 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.

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

    DOEpatents

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

  9. Method and apparatus 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)

    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.

  10. Influence of a weak dc electric field on tricritical phase transition in TGSe: evidence of different specific heat behaviour on cooling and heating runs

    NASA Astrophysics Data System (ADS)

    Romero, F. J.; Gallardo, M. C.; Jimnez, J.; del Cerro, J.

    2006-11-01

    The para-ferroelectric tricritical phase transition of a single crystal of triglycine selenate (TGSe) has been studied in the neighbourhood of the transition temperature, under weak electric fields, E, using a highly sensitive calorimetric technique. The specific heat, cE, under fields in the range between 5 and 175 V cm-1 and close to transition temperature (0.2 K), shows different behaviour on cooling and on heating at a temperature variation rate of 0.03 K h-1 for Tphase. The different relation between ? and E obtained on heating and on cooling runs is discussed and it is concluded that data on heating correspond to the thermal equilibrium.

  11. 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.

  12. 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.

  13. 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.

  14. 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.%.

  15. Bellingham Phase 3, Engineering and technology development for a hot-water district-heating system employing thermal-energy storage

    NASA Astrophysics Data System (ADS)

    Vanroyen, G. L.

    1981-11-01

    Thermal energy storage in a district heating system which requires the integration of customer consumption rates, weather and other system operating conditions, as well as economic payback is evaluated. Generic methods of approaching and evaluating these factors are essential to insure that the most economical district heating projects are selected for development and that those systems are designed and operated in the most cost effective manner. Also, governmental and legal guidelines for interfacing with users, financing, and municipal utility regulations are examined

  16. 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.

  17. 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.

  18. Cooling of safety rods in the Savannah River K Reactor during the gamma heating phase of a postulated loss-of-coolant accident

    SciTech Connect

    Pasamehmetoglu, K.O.; Unal, C.; Motley, F.E.; Rodriguez, S.B.

    1992-01-01

    This paper documents the heat-transfer analysis for the safety rod placed in a perforated guide tube during the gamma heating phase of a large-break loss of coolant accident in Savannah River K-reactor. The cooling mechanisms are natural convection to air and radiation to the surrounding structures. The limiting component is the guide tube. The guide tube is shown to remain coolable below its thermal limit for the anticipated reactor powers unless it is contacted by the hotter safety rod. Sample calculations are performed for various contact scenarios, and the results are reported within the paper. The results indicate that the most limiting contact scenario results when the safety rod heats up to its maximum temperature while remaining concentric in the guide tube and then contacts the guide tube. The worse contact location appears to be in line with the slugs-cladding contact and in between the rows of holes in the guide tube.

  19. Cooling of safety rods in the Savannah River K Reactor during the gamma heating phase of a postulated loss-of-coolant accident

    SciTech Connect

    Pasamehmetoglu, K.O.; Unal, C.; Motley, F.E.; Rodriguez, S.B.

    1992-12-01

    This paper documents the heat-transfer analysis for the safety rod placed in a perforated guide tube during the gamma heating phase of a large-break loss of coolant accident in Savannah River K-reactor. The cooling mechanisms are natural convection to air and radiation to the surrounding structures. The limiting component is the guide tube. The guide tube is shown to remain coolable below its thermal limit for the anticipated reactor powers unless it is contacted by the hotter safety rod. Sample calculations are performed for various contact scenarios, and the results are reported within the paper. The results indicate that the most limiting contact scenario results when the safety rod heats up to its maximum temperature while remaining concentric in the guide tube and then contacts the guide tube. The worse contact location appears to be in line with the slugs-cladding contact and in between the rows of holes in the guide tube.

  20. Gas cooled solar power plant for generating electrical energy in the 20MWe operating range (GAST): Preliminary design phase

    NASA Astrophysics Data System (ADS)

    Kostrzewa, S.; Wehowsky, P.

    1981-07-01

    R&D work required for the erection of a pilot plant was defined. Since the location of the site is not yet determined, the project work was based on preliminary basic data. Significant results of the preliminary design phase include both the choice of a combined gas/steam thermal energy conversion process for the reference concept and basic concepts for heliostat, heliostat field arrangement, receiver, tower and master control/process computer system.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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

  6. Comparison of concepts for solar-heated or solar-driven absorption and compression cooling machines for air conditioning and food preservation purposes, phase 1

    NASA Astrophysics Data System (ADS)

    Grallert, H.; Herbricht, M.; Margulies, M.

    1981-09-01

    For the cooling power range of about 10 to 500 kW and for cooling temperatures of +20, 0, and -20 C, a comparison was made between solar heated absorption machines and compression machines, which are driven by a solar heated Rankine cycle. Comparison criteria are C.O.P., energy prices, and application risks. All partial efficiencies and costs were determinated by component analyses. For several cooling loads an annual system simulation was performed using MBB computer programs. Furthermore, the electric energy demand for absorption cooling systems was estimated and initial application recommendations are given.

  7. 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

  8. Cooled railplug

    DOEpatents

    Weldon, William F. (Austin, TX)

    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.

  9. 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.

  10. 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.

  11. 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.

  12. Cool Vest

    NASA Technical Reports Server (NTRS)

    1982-01-01

    ILC, Dover Division's lightweight cooling garment, called Cool Vest was designed to eliminate the harmful effects of heat stress; increases tolerance time in hot environments by almost 300 percent. Made of urethane-coated nylon used in Apollo, it works to keep the body cool, circulating chilled water throughout the lining by means of a small battery-powered pump. A pocket houses the pump, battery and the coolant which can be ice or a frozen gel, a valve control allows temperature regulation. One version is self-contained and portable for unrestrained movement, another has an umbilical line attached to an external source of coolant, such as standard tap water, when extended mobility is not required. It is reported from customers that the Cool Vest pays for itself in increased productivity in very high temperatures.

  13. Cool School.

    ERIC Educational Resources Information Center

    Stephens, Suzanne

    1980-01-01

    The design for Floyd Elementary School in Miami (Florida) seeks to harness solar energy to provide at least 70 percent of the annual energy for cooling needs and 90 percent for hot water. (Author/MLF)

  14. 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

  15. 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 Districts 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: 1.7018.06). Residing in Awach sub-county (AOR, 2.93; 95% CI: 1.286.68), experiencing STI symptoms in the previous 12 months (AOR, 2.36; 95% CI: 1.436.17), and practicing dry sex (AOR, 2.31; 95% CI: 1.045.13) 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

  16. 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.

  17. 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.

  18. Cooling Vest

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Because quadriplegics are unable to perspire below the level of spinal injury, they cannot tolerate heat stress. A cooling vest developed by Ames Research Center and Upjohn Company allows them to participate in outdoor activities. The vest is an adaptation of Ames technology for thermal control garments used to remove excess body heat of astronauts. The vest consists of a series of corrugated channels through which cooled water circulates. Its two outer layers are urethane coated nylon, and there is an inner layer which incorporates the corrugated channels. It can be worn as a backpack or affixed to a wheelchair. The unit includes a rechargeable battery, mini-pump, two quart reservoir and heat sink to cool the water.

  19. 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.

  20. 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

  1. 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…

  2. School District AIDS Policies.

    ERIC Educational Resources Information Center

    Strouse, Joan H.

    1990-01-01

    Discusses whether school districts are prepared to deal with AIDS among students and school personnel based on questionnaire data. Results indicate a lack of preparedness for these situations. Discusses why districts lack written policies to deal with these situations and what type of AIDS policy a school district should have. (JS)

  3. 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.

  4. Cooling vest

    NASA Technical Reports Server (NTRS)

    Kosmo, J.; Kane, J.; Coverdale, J.

    1977-01-01

    Inexpensive vest of heat-sealable urethane material, when strapped to person's body, presents significant uncomplicated cooling system for environments where heavy accumulation of metabolic heat exists. Garment is applicable to occupations where physical exertion is required under heavy protective clothing.

  5. 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.

  6. 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.

  7. Effect of oxygen on phase formation and thermal stability of slowly cooled Zr{sub 65}Al{sub 7.5}Cu{sub 17.5}Ni{sub 10} metallic glass

    SciTech Connect

    Gebert, A.; Eckert, J.; Schultz, L.

    1998-09-18

    The effect of small amounts of oxygen (0.28--0.6 at.%) on the phase formation and the thermal stability of bulk samples of the Zr{sub 65}Al{sub 7.5}Cu{sub 17.5}Ni{sub 10} alloy prepared by die casting into a copper mould has been studied by X-ray diffraction, microstructural characterization and differential scanning calorimetry. In contrast to rapidly quenched ribbons, the crystalline volume fraction in slowly cooled bulk samples increases with increasing oxygen content. Oxygen triggers the formation of a metastable f.c.c. NiZr{sub 2}-type crystalline phase which also depends on the local cooling conditions during casting. The processes o the oxygen-induced crystallization are discussed in detail considering initial nucleation of metastable f.c.c. crystalline phases. Furthermore, there is a strong influence of the oxygen content on the thermal stability during constant-rate heating to elevated temperatures. With increasing oxygen content a drastic reduction of the supercooled liquid region is observed, resulting mainly from a change of the crystallization sequence from a single- to a double-step process which is attributed to the oxygen-triggered formation and the subsequent transformation of the metastable f.c.c. phase.

  8. 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.

  9. 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.

  10. 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

  11. New directions for district heating in the United States

    NASA Astrophysics Data System (ADS)

    Olszewski, M.; Karnitz, M. A.

    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. Five major district heating projects moving into the construction and demonstration phase are described. Although all have hot water distribution systems, a variety of heat sources are utilized. These include geothermal water, industrial reject heat, and utility cogeneration using coal-fired power plants.

  12. Mergers, cooling flows, and evaporation

    NASA Technical Reports Server (NTRS)

    Sparks, W. B.

    1993-01-01

    Mergers (the capture of cold gas, especially) can have a profound influence on the hot coronal gas of early-type galaxies and clusters, potentially inducing symptoms hitherto attributed to a cooling flow, if thermal conduction is operative in the coronal plasma. Heat can be conducted from the hot phase into the cold phase, simultaneously ionizing the cold gas to make optical filaments, while locally cooling the coronal gas to mimic a cooling-flow. If there is heat conduction, though, there is no standard cooling-flow since radiative losses are balanced by conduction and not mass deposition. Amongst the strongest observational support for the existence of cooling-flows is the presence of intermediate temperature gas with x-ray emission-line strengths in agreement with cooling-flow models. Here, x-ray line strengths are calculated for this alternative model, in which mergers are responsible for the observed optical and x-ray properties. Since gas around 10(exp 4) K is thermally stable, the cold cloud need not necessarily evaporate and hydrostatic solutions exist. Good agreement with the x-ray data is obtained. The relative strengths of intermediate temperature x-ray emission lines are in significantly better agreement with a simple conduction model than with published cooling-flow models. The good agreement of the conduction model with optical, infrared and x-ray data indicates that significantly more theoretical effort into this type of solution would be profitable.

  13. Sorption cooling: a valid extension to passive cooling

    NASA Astrophysics Data System (ADS)

    Doornink, Jan; Burger, Johannes; ter Brake, Marcel

    2007-10-01

    Passive cooling has shown to be a very dependable cryogenic cooling method for space missions. Several missions employ passive radiators to cool down their delicate sensor systems for many years, without consuming power, without exporting vibrations or producing electromagnetic interference. So for a number of applications, passive cooling is a good choice. At lower temperatures, the passive coolers run into limitations that prohibit accommodation on a spacecraft. The approach to this issue has been to find a technology able to supplement passive cooling for lower temperatures, which maintains as much as possible of the advantages of passive coolers. Sorption cooling employs a closed cycle Joule-Thomson expansion process to achieve the cooling effect. Sorption cells perform the compression phase in this cycle. At a low temperature and pressure, these cells adsorb the working fluid. At a higher temperature they desorb the fluid and thus produce a high-pressure flow to the restriction in the cold stage. The sorption process selected for this application is of the physical type, which is completely reversible. It does not suffer from degradation as is the case with chemical sorption of e.g. hydrogen in metal hydrides. Sorption coolers include no moving parts except for some check valves, they export neither mechanical vibrations nor electromagnetic interference, and are potentially very dependable due to their simplicity. The required cooling temperature determines the type of working fluid to be applied. Sorption coolers can be used in conjunction with passive cooling for heat rejection at different levels. This paper starts with a brief discussion on applications of passive coolers in different types of orbits and the limitations on passive cooling at low cooling temperatures. Next, the working principle of sorption cooling is summarized. The DARWIN mission is chosen as an example application of sorption and passive cooling and special attention is paid to the reduction of the radiator area needed by the sorption cooler. By examining the performance of alternative working fluids suitable for different cooling temperatures, the application field of this type of sorption cooling is currently expanded.

  14. Sorption cooling: A valid extension to passive cooling

    NASA Astrophysics Data System (ADS)

    Doornink, D. J.; Burger, J. F.; ter Brake, H. J. M.

    2008-05-01

    Passive cooling has shown to be a very dependable cryogenic cooling method for space missions. Several missions employ passive radiators to cool down their delicate sensor systems for many years, without consuming power, without exporting vibrations or producing electromagnetic interference. So for a number of applications, passive cooling is a good choice. At lower temperatures, the passive coolers run into limitations that prohibit accommodation on a spacecraft. The approach to this issue has been to find a technology able to supplement passive cooling for lower temperatures, which maintains as much as possible of the advantages of passive coolers. Sorption cooling employs a closed cycle Joule-Thomson expansion process to achieve the cooling effect. Sorption cells perform the compression phase in this cycle. At a low temperature and pressure, these cells adsorb the working fluid. At a higher temperature they desorb the fluid and thus produce a high-pressure flow to the expander in the cold stage. The sorption process selected for this application is of the physical type, which is completely reversible. It does not suffer from degradation as is the case with chemical sorption of, e.g., hydrogen in metal hydrides. Sorption coolers include no moving parts except for some check valves, they export neither mechanical vibrations nor electromagnetic interference, and are potentially very dependable due to their simplicity. The required cooling temperature determines the type of working fluid to be applied. Sorption coolers can be used in conjunction with passive cooling for heat rejection at different levels. This paper starts with a brief discussion on applications of passive coolers in different types of orbits and on the limitations of passive cooling for lower cooling temperatures. Next, the working principle of sorption cooling is summarized. The DARWIN mission is chosen as an example application of sorption and passive cooling and special attention is paid to the reduction of the radiator area needed by the sorption cooler. The application field of this type of sorption cooling in space missions is currently being expanded by examining the performance of alternative working fluids, suitable for different cooling temperatures.

  15. 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.

  16. 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

  17. 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

  18. 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.

  19. 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…

  20. 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

  1. 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.

  2. 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.

  3. PHASE TRANSITIONS AND He-SYNTHESIS-DRIVEN WINDS IN NEUTRINO COOLED ACCRETION DISKS: PROSPECTS FOR LATE FLARES IN SHORT GAMMA-RAY BURSTS

    SciTech Connect

    Lee, William H.; Lopez-Camara, Diego; Ramirez-Ruiz, Enrico

    2009-07-10

    We consider the long-term evolution of debris following the tidal disruption of compact stars in the context of short gamma ray bursts. The initial encounter impulsively creates a hot, dense, neutrino-cooled disk capable of powering the prompt emission. After a long delay, we find that powerful winds are launched from the surface of the disk, driven by the recombination of free nucleons into {alpha}-particles. The associated energy release depletes the mass supply and eventually shuts off activity of the central engine. As a result, the luminosity and mass accretion rate deviate from the earlier self-similar behavior expected for an isolated ring with efficient cooling. This then enables a secondary episode of delayed activity to become prominent as an observable signature, when material in the tidal tails produced by the initial encounter returns to the vicinity of the central object. The timescale of the new accretion event can reach tens of seconds to minutes, depending on the details of the system. The associated energies and timescales are consistent with those occurring in X-ray flares.

  4. 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.

  5. Is a Monolithic Dome in Your District's Future?

    ERIC Educational Resources Information Center

    Lanham, Carol

    2000-01-01

    Monolithic domes are less costly to build than traditional structures and can cost as much as 50 percent less to heat and cool. Districts across the country that have opted for monolithic-dome school facilities say their decision was a cost-effective alternative to conventional construction. (MLH)

  6. 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…

  7. 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.

  8. Integrated gas-fired desiccant dehumidification vapor-compression cooling system for residential application. Phase 1. Final report, December 1986-December 1987

    SciTech Connect

    Lowenstein, A.; Marsala, J.; Spatz, M.; Feldman, S.; Tandler, J.

    1988-11-01

    The development of an air conditioner that uses a liquid-desiccant dehumidifier is described. Three air-conditioning systems that integrate the operation of a conventional vapor-compression system with a liquid-desiccant dehumidifier were first simulated in seasonal performance studies. These studies showed that there was little benefit from attempting to recover reject heat from the vapor-compression system for regenerating the liquid desiccant. The preferred version of the liquid-desiccant dehumidifier was one that used a simple gas-fired boiler for regenerating the desiccant. When added to a conventional vapor-compression air conditioner, this liquid-desiccant system could maintain comfortable humidity levels in the living space for almost the entire cooling season at a modest premium in operating costs.

  9. Integrated gas-fired desiccant dehumidification vapor compression cooling system for residential applications. Phase 3, Final report, January 1990-December 1991

    SciTech Connect

    Feldman, S.; Bacchus, R.; Marsala, J.; Popelka, A.

    1991-12-01

    A residential liquid desiccant-boosted evaporative cooling system was developed. The major components included a cross-flow heat exchanger, interchange heat exchanger, and brine boiler. The unit measures approximately 64 inch (L) x 46 inch (W) x 49 inch (H). Economic studies using DOE-2 project a large market potential for the system, with Fresno, California, and El Paso, Texas, the top two market areas. Considerable engineering effort must still be carried out before the system can be commercialized. Some of the outstanding issues include the development of a method for mass-producing a low-cost leaktight cross-flow heat exchanger, tests for corrosion in the boiler, and the development of system controls.

  10. 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.

  11. 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

  12. 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.

  13. Mars Pathfinder mechanically pumped cooling loop

    NASA Technical Reports Server (NTRS)

    Birur, G. C.

    2001-01-01

    A mechanically pumped single-phase cooling loop was successfully flown on the Mars Pathfinder (MPF) Spacecraft which safely landed on the Martian surface on July 4, 1997. One of the key technologies that enabled the mission to succeed was an active heat rejection system (HRS) used to cool the electronics on the spacecraft during its seven-month cruise from Earth to Mars.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. Superconducting magnet system for muon beam cooling

    SciTech Connect

    Andreev, N.; Johnson, R.P.; Kashikhin, V.S.; Kashikhin, V.V.; Novitski, I.; Yonehara, K.; Zlobin, A.; /Fermilab

    2006-08-01

    A helical cooling channel has been proposed to quickly reduce the six-dimensional phase space of muon beams for muon colliders, neutrino factories, and intense muon sources. A novel superconducting magnet system for a muon beam cooling experiment is being designed at Fermilab. The inner volume of the cooling channel is filled with liquid helium where passing muon beam can be decelerated and cooled in a process of ionization energy loss. The magnet parameters are optimized to match the momentum of the beam as it slows down. The results of 3D magnetic analysis for two designs of magnet system, mechanical and quench protection considerations are discussed.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. Free cooling considerations

    SciTech Connect

    Kelley, D.W.

    1996-08-01

    This is a discussion of the application of water-side free cooling utilizing plate-and-frame heat exchangers (HX). Free cooling is the production of chilled water without the use of chillers. The heat removed from the building`s cooling coils is transferred, through the HX to the cooling towers for rejection to the atmosphere. Free cooling is not really free; even though the chiller is off, chilled and tower water pumps and cooling tower fan(s) are required to operate. This article is broken into three sections that present considerations on how to design the building`s cooling system(s) to get the most out of free cooling, considerations for the chilled water side of the free cooling system, and considerations for the cooling tower water side of the system.

  4. 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

  5. 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.

  6. 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.

  7. Integrated gas-fired desiccant dehumidification vapor-compression cooling system for residential application. Phase 2. Final report, December 1987-December 1988

    SciTech Connect

    Bartz, D.; Zografos, A.; Marsala, J.

    1989-10-01

    Field tests of a residential liquid-desiccant dehumidifier are described. From analysis done in Phase I of this program, a gas-fired boiler for regenerating the desiccant was selected with a one-ton capacity dehumidifier. Three field-experiment units were built. One was installed at a test house in Gaithersburg, Maryland owned by GEOMET Technologies. The second was installed in Atlanta, Georgia, supported by the Atlanta Gas Light Company. The third unit was shipped to Lone Star Gas Company, Forth Worth, Texas, to be installed in 1989. Once startup problems were corrected, the units ran reliably, controlling indoor humidity accurately. The seasonal COP for the Gaithersburg installation was 0.58; for Atlanta the COP was 0.50. By extending the operating periods (typically 5 minutes in these tests), the COP should increase. A manufacturing cost study of the residential dehumidifier showed that a factory cost of $553.62/unit is achieved at 50,000 units/year volume.

  8. 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)

  9. 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)

  10. 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…

  11. Districts Delivering Online

    ERIC Educational Resources Information Center

    Sternberg, Ruth

    2006-01-01

    The idea is not new: Offer courses remotely, build in variety and the students will come. This article discusses how public schools are investing in offering online courses, catering to students' specific learning needs and to remote locations. Several surveys conducted in recent years show that school districts nationwide are embracing this

  12. 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

  13. 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

  14. 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…

  15. 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

  16. 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

  17. District Program Review Process.

    ERIC Educational Resources Information Center

    Christiansen, L. E.; Katterle, Zeno

    These materials from Beaverton Schools, District Number 48 (Oregon) provide an annual program review process within the context of the regular planning and budgeting processes. Information obtained from the review process (an analytic and decision-making process) is intended to serve as a basis for determining what program levels should be

  18. 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

  19. 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…

  20. 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

  1. 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,…

  2. 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...

  3. Problems of Affluent School Districts.

    ERIC Educational Resources Information Center

    McLoone, Eugene P.

    All school districts are affected by the stagnant economy, the growing needs of the public sector, the increased burden of transfer payments, and the limited growth of public revenues. Retrenchment is common to all school districts, but it may be more severe in affluent districts. By 1969-70, suburban school systems were the clear-cut expenditure

  4. A District Level Planning Model.

    ERIC Educational Resources Information Center

    McHenry, W. E.; Achilles, C. M.

    This report examines school district planning models in South Carolina. It focuses on three questions: (1) Of those school districts conducting some type of systematic planning, how many are producing strategic plans? Long-range plans? Accountability reports? (2) In those same districts, how many are preparing adequate program-management

  5. 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…

  6. 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.

  7. 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.

  8. 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.

  9. Data center cooling system

    DOEpatents

    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.

  10. 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.

  11. 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.

  12. 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.

  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. 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.

  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. 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

  17. 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.

  18. 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.

  19. Pumps, valves and piping for cogeneration and district heating

    SciTech Connect

    O'Keefe, W.

    1993-01-01

    The two concepts of cogeneration (cogen) and district heating (DH) have certain points of similarity. They are both quite old, fell into disuse some decades ago, have had a renaissance of late, and often are plagued by economics that are only marginal. At present, however, both cogeneration and district heating ride a wave of popular fancy and regulatory whim, all of which has had as one result the inducing of swarms of lawyers and financial soldiers of fortune to flock to the standards, for at least the time being. Although the finances of the two technologies frequently call for innovation, at least the fluid-handling engineering problems are not extraordinary. Pressures, temperatures, flow rates, and corrosion dangers are nearly always within readily mastered limits. The major difficulties arise generally either from the indifference and parsimony of the owners or from the ignorance of the plant management and operations personnel. This report intends to be only a general perspective which the reader must enlarge upon by such other aids as POWER special reports on narrower sectors. Retain in mind the basic definitions for the two technologies: Cogeneration is a simultaneous production of both useful thermal energy (as steam, hot water, or hot gas) and electric power from a fuel source. District heating is the supplying of thermal energy in steam or water to remote and usually noncontiguous locations which are often under separate ownership. District cooling, the increasingly popular supplement to district heating, supplies chilled water under similar circumstances.

  20. 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.

  1. Gas turbine cooling system

    DOEpatents

    Bancalari, Eduardo E. (Orlando, FL)

    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).

  2. NASA Microclimate Cooling Challenges

    NASA Technical Reports Server (NTRS)

    Trevino, Luis A.

    2004-01-01

    The purpose of this outline form presentation is to present NASA's challenges in microclimate cooling as related to the spacesuit. An overview of spacesuit flight-rated personal cooling systems is presented, which includes a brief history of cooling systems from Gemini through Space Station missions. The roles of the liquid cooling garment, thermal environment extremes, the sublimator, multi-layer insulation, and helmet visor UV and solar coatings are reviewed. A second section is presented on advanced personal cooling systems studies, which include heat acquisition studies on cooling garments, heat rejection studies on water boiler & radiators, thermal storage studies, and insulation studies. Past and present research and development and challenges are summarized for the advanced studies.

  3. Memory coherence of a sympathetically cooled trapped-ion qubit

    NASA Astrophysics Data System (ADS)

    Home, J. P.; McDonnell, M. J.; Szwer, D. J.; Keitch, B. C.; Lucas, D. M.; Stacey, D. N.; Steane, A. M.

    2009-05-01

    We demonstrate sympathetic cooling of a C43a+ trapped-ion memory qubit by a C40a+ coolant ion sufficiently near the ground state of motion for fault-tolerant quantum logic, while maintaining coherence of the qubit. This is an essential ingredient in trapped-ion quantum computers. The isotope shifts are sufficient to suppress decoherence and phase shifts of the memory qubit due to the cooling light which illuminates both ions. We measure the qubit coherence during ten cycles of sideband cooling, finding a coherence loss of 3.3% per cooling cycle. The natural limit of the method is O(10-4) infidelity per cooling cycle.

  4. Minneapolis district-heating options

    SciTech Connect

    Stovall, T.K.; Borkowski, R.J.; Karnitz, M.A.; Strom, S.; Linwick, K.

    1981-10-01

    A study was undertaken to determine the feasibility of a large-scale district heating system for the Minneapolis central city area. The analysis was based on a previous city of St. Paul hot-water district heating study and other studies done by a Swedish engineering firm, Studsvik Energiteknik A.B. Capital costs such as building and heat source conversion, pipeline construction, and equipment were used in comparing the projected expenses of various district heating scenarios. Options such as coal, refuse-derived fuel burning, and cogeneration at the Riverside Power Station were discussed as energy supplies for a cost-effective district heating system.

  5. 7 CFR 945.22 - Districts.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... districts of the production area are hereby established: Provided, That these districts may be changed as..., Madison, and Teton; (b) District No. 2: The counties of Bannock, Bear Lake, Bingham, Caribou, Franklin... in Idaho included in the production area, and not included in District No. 1 or District No. 2....

  6. 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…

  7. Solar heating and cooling

    NASA Technical Reports Server (NTRS)

    Bartera, R. E.

    1978-01-01

    To emphasize energy conservation and low cost energy, the systems of solar heating and cooling are analyzed and compared with fossil fuel systems. The application of solar heating and cooling systems for industrial and domestic use are discussed. Topics of discussion include: solar collectors; space heating; pools and spas; domestic hot water; industrial heat less than 200 F; space cooling; industrial steam; and initial systems cost. A question and answer period is generated which closes out the discussion.

  8. 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.}

  9. Power electronics cooling apparatus

    DOEpatents

    Sanger, Philip Albert (Monroeville, PA); Lindberg, Frank A. (Baltimore, MD); Garcen, Walter (Glen Burnie, MD)

    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.

  10. Hydrogen film cooling investigation

    NASA Technical Reports Server (NTRS)

    Rousar, D. C.; Ewen, R. L.

    1973-01-01

    Effects of flow turning, flow acceleration, and supersonic flow on film cooling were determined experimentally and correlated in terms of an entrainment film cooling model. Experiments were conducted using thin walled metal test sections, hot nitrogen mainstream gas, and ambient hydrogen or nitrogen as film coolants. The entrainment film cooling model relates film cooling effectiveness to the amount of mainstream gases entrained with the film coolant in a mixing layer. The experimental apparatus and the analytical model used are described in detail and correlations for the entrainment fraction and film coolant-to-wall heat transfer coefficient are presented.

  11. Algorithmic Quantum Cooling

    NASA Astrophysics Data System (ADS)

    Yung, Man Hong; Boixo, Sergio; Aspuru-Guzik, Alan

    2012-02-01

    Efficient methods of cooling are essential for exploring the fundamental properties of low temperature physics. A remarkable cooling method is known as the evaporative cooling (or ``coffee'' cooling), where energetic particles are filtered away so as to lower the mean energy of the rest of the system. Inspired by the idea of evaporative cooling, we developed a method called algorithmic quantum cooling (AQC) for achieving the goal of cooling for any physical system which is simulable by a quantum computer. The novel feature of AQC is that the evolution of the state of the system is modeled as the movement of a one-dimensional classical random walk; the walker plays the role of the motion of the gas particles in an ordinary evaporative cooling. The implementation of this method is analogous to the setting of Maxwell's demon, where the experimentalist can monitor the heat-up or cool-down of the system, and apply feedback control to the resulting states. Here we cover the results of the connection of AQC with quantum non-demolition measurement, a scaling analysis of AQC, and the application of amplitude amplification to achieve quantum speedup. Experimental realization of AQC can be accomplished with currently available technologies.

  12. 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.

  13. Passive containment cooling system

    DOEpatents

    Conway, Lawrence E. (Robinson Township, Allegheny County, PA); Stewart, William A. (Penn Hills Township, Allegheny County, PA)

    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.

  14. 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.

  15. 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…

  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. 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...

  18. 7 CFR 946.31 - Districts.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 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...

  19. Ionization Cooling Using a Parametric Resonance

    SciTech Connect

    Y.S. Derbenev; R.P. Johnson

    2005-05-16

    Muon collider luminosity depends on the number of muons in the storage ring and on the transverse size of the beams in collision. Ionization cooling as it is presently envisioned will not cool the beam sizes sufficiently well to provide adequate luminosity without large muon intensities. A new idea to combine ionization cooling with parametric resonances has been developed that will lead to beams with much smaller sizes so that high luminosity in a muon collider can be achieved with fewer muons. In the linear channel described here, a half integer resonance is induced such that the normal elliptical motion of particles in x-x' phase space becomes hyperbolic, with particles moving to smaller x and larger x' as they pass down the channel. Thin absorbers placed at the focal points of the channel then cool the angular divergence of the beam by the usual ionization cooling mechanism where each absorber is followed by RF cavities. We discuss the theory of Parametric-resonance Ionization Cooling, including the sensitivity to aberrations and the need to start with a beam that has already been cooled adequately.

  20. 'Cool runnings': heat stroke in cool conditions.

    PubMed

    Robertson, Brian; Walter, Edward

    2010-05-01

    Heat stroke is rare and usually occurs in warm conditions. It is often fatal. This paper reports six runners from two road-running events who developed heat stroke despite cool conditions and who improved quickly with immediate treatment. PMID:20442171

  1. Liquid metal cooled nuclear reactors with passive cooling system

    DOEpatents

    Hunsbedt, Anstein (Los Gatos, CA); Fanning, Alan W. (San Jose, CA)

    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.

  2. 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…

  3. 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

  4. A Tale of Two Districts

    ERIC Educational Resources Information Center

    Simon, Mark

    2012-01-01

    These days, everyone seems to be wringing their hands about how to construct new evaluation systems that will make teachers better. This unnecessary angst has led to crazy experiments in reform that have embraced churn for the sake of churn, put school districts at risk, and demoralized many of the most talented teachers. A few school districts,

  5. 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

  6. 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

  7. 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)

  8. Electoral Competition in Heterogeneous Districts

    ERIC Educational Resources Information Center

    Callander, Steven

    2005-01-01

    This paper considers a model of elections in which parties compete simultaneously for multiple districts. I show that if districts are heterogeneous, then a unique two-party equilibrium exists under plurality rule in which further entry is deterred. The equilibrium requires that parties choose noncentrist policy platforms and not converge to the

  9. 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

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  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. 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…

  18. 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

  19. 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.

  20. 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.

  1. Turbine blade cooling

    DOEpatents

    Staub, Fred Wolf (Schenectady, NY); Willett, Fred Thomas (Niskayuna, NY)

    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.

  2. Turbine blade cooling

    DOEpatents

    Staub, Fred Wolf (Schenectady, NY); Willett, Fred Thomas (Niskayuna, NY)

    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.

  3. 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.

  4. Hydronic rooftop cooling systems

    SciTech Connect

    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.

  5. 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.

  6. Water cooled steam jet

    DOEpatents

    Wagner, Jr., Edward P. (Idaho Falls, ID)

    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.

  7. 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.

  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. 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.

  10. 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

  11. 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.

  12. Commercial space cooling and air handling technology atlas

    SciTech Connect

    1995-07-01

    Buildings can cost less to construct and be more comfortable. This report tells how reduced cooling loads and whole-system integration of properly sized cooling and air handling equipment can save money and energy, increase occupant comfort, enhance productivity, and free up valuable space. Topics include end use and market data, efficiency standards, indoor air quality, the effects of the CFC phase-out, as well as in-depth technological assessments of load reduction, air handling systems and components, evaporative and radiative cooling and other alternative cooling techniques, unitary and central cooling systems, gas cooling, and thermal storage systems. The appendices contain lists of manufacturers and trade, professional, governmental, and public interest organizations in the space cooling and air handling field, as well as an index.

  13. 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…

  14. Small School District Saves Money with Energy Grant.

    ERIC Educational Resources Information Center

    Kussmaul, Donald L.

    1983-01-01

    Describes how the small Tiskilwa (Illinois) school district used a United States Department of Energy grant to replace and block windows and insulate the attic in the elementary school. Describes savings in dollars and energy resulting from the energy audit and technical assistance phases of the project. (SB)

  15. 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…

  16. 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

  17. 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…

  18. 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

  19. 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.

  20. 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

  1. 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.

  2. 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.

  3. 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).

  4. Cooling of solar flares plasmas. 1: Theoretical considerations

    NASA Astrophysics Data System (ADS)

    Cargill, Peter J.; Mariska, John T.; Antiochos, Spiro K.

    1995-02-01

    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 L5/6/p1/6, where the coronal phase (defined as the time maximum temperature). When the conductive cooling is static, the cooling time scales as L3/4n1/4. In deriving these results, use was made of an important scaling law (T proportional to n2) 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-2. It is shown that these scaling laws are part of a class of analytic solutions developed by Antiocos (1980).

  5. Electronic Cooling in Graphene

    NASA Astrophysics Data System (ADS)

    Bistritzer, R.; MacDonald, A. H.

    2009-05-01

    Energy transfer to acoustic phonons is the dominant low-temperature cooling channel of electrons in a crystal. For cold neutral graphene we find that the weak cooling power of its acoustic modes relative to their heat capacity leads to a power-law decay of the electronic temperature when far from equilibrium. For heavily doped graphene a high electronic temperature is shown to initially decrease linearly with time at a rate proportional to n3/2 with n being the electronic density. The temperature at which cooling via optical phonon emission begins to dominate depends on graphene carrier density.

  6. Effect of sintering temperature and cooling rate on microstructure, phase formation, and critical current density of Ag-sheathed Bi{sub 1.8}Pb{sub 0.4}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x} superconducting tapes

    SciTech Connect

    Singh, J.P.; Vasanthamohan, N.

    1998-02-01

    Silver-sheathed Bi{endash}Pb{endash}Sr{endash}Ca{endash}Cu{endash}O (2223) superconducting tapes (with a starting composition of Bi{sub 1.8}Pb{sub 0.4}Sr{sub 2}Ca{sub 1}Cu{sub 2}O{sub 8}, calcium cuprate, and CuO) were fabricated by the powder-in-tube technique. The tapes were sintered at various temperatures to optimize the formation of Bi{sub 1.8}Pb{sub 0.4}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10} phase within the tape. The results show that sintering within the temperature range of 815{endash}825{degree}C can produce tapes with high critical current density (J{sub c}). The J{sub c} of samples sintered at the higher temperature of 825{degree}C, where more liquid is present, depended markedly on the rate at which tapes were cooled from the sintering temperature; samples sintered at lower temperatures did not exhibit such a cooling-rate effect. The optimum combination of phase purity and microstructure that yielded an average transport J{sub c} of {ge}2.5{times}10{sup 4}A/cm{sup 2} was obtained when the tapes were sintered at 825{degree}C for 150 h and cooled at a rate of 25{degree}C/h from the sintering temperature. Quenching studies indicate that the Bi-2223 phase becomes unstable below 700{degree}C during slow cooling. This result may have important implications for processing Bi{endash}Sr{endash}Ca{endash}Cu{endash}O tapes with high J{sub c}. Addition of 15 vol.{percent} Ag flakes to the monolithic core exerted no significant effect on J{sub c}. {copyright} {ital 1998 Materials Research Society.}

  7. 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

  8. 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.

  9. 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.

  10. 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.

  11. 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)

  12. 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.

  13. 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.

  14. Sub-cooled nitrogen cryogenic cooling system for superconducting fault current limiter by using GM-cryocooler

    NASA Astrophysics Data System (ADS)

    Kang, Hyoungku; Kim, Hyung Jin; Bae, Duck Kweon; Ahn, Min Cheol; Chang, Ho-Myung; Ko, Tae Kuk

    2005-01-01

    The 21st Century Frontier R&D Program was planned to develop and commercialize the inductive Superconducting Fault Current Limiter (SFCL) in Korea until 2011. The 1.2 kV/80 A inductive SFCL was planned to develop at the first year in the first phase (2001-2002) and the 6.6 kV/200 A inductive SFCL for short run operation test was planned to develop at the second and third year in the first phase (2002-2004). The experimental characteristics of conduction-cooled cooling system developed in the first year was very weak from the sudden large thermal disturbance. Therefore, the conduction-cooled cooling system was concluded not appropriate for the cryogenic technology of the application of superconducting fault current limiter. In the third year research, the improved sub-cooled nitrogen cooling system was adopted and investigated. In this paper, the characteristics of each cooling type was compared and the basic deign of ameliorated cooling system was introduced and the total heat load of the cooling system was calculated and compared with the heat load of the cooling system developed at 2nd year research.

  15. Refrigerant directly cooled capacitors

    DOEpatents

    Hsu, John S. (Oak Ridge, TN); Seiber, Larry E. (Oak Ridge, TN); Marlino, Laura D. (Oak Ridge, TN); Ayers, Curtis W. (Kingston, TN)

    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.

  16. 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)

  17. 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.

  18. 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.

  19. Electron cooling for RHIC

    SciTech Connect

    Burov, A., FNAL,

    1998-09-25

    Electron cooling of completely stripped gold ions {sup 197}Au{sup 79+} in RHIC is considered for the store energy, {gamma} = 108. The optimal parameters of the required electron storage ring are discussed and proposed. The cooling time is calculated as 15 minutes, which would allow not only to avoid the beam loss due to the intra-beam scattering, but also reduce the transverse emittance and increase the luminosity several times.

  20. 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.

  1. 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.

  2. Rapid cooling for saving lives: a bioengineering opportunity.

    PubMed

    Lampe, Joshua W; Becker, Lance B

    2007-07-01

    The induction of mild hypothermia, lowering body temperature by 4 degrees C, is gaining acceptance as an acute therapy for the treatment of hypoxia and ischemia following cardiac arrest and many life-threatening injuries. When hypothermia is used following ischemia (as opposed to before ischemia), it needs to be performed rapidly for the greatest benefit, preferably within 5 min. When we consider the basic heat-transfer problem and define the engineering parameter space, we find that almost 3900 W of cooling are required in order to achieve 4 degrees C cooling within 5 min. A simple model reveals that this poses a significant bioengineering challenge as the rate of heat transfer is severely limited, owing to a relatively confined fundamental parameter space. Current methods of cooling include external cooling devices, such as cooling blankets or ice bags, which are simple to use, relatively inexpensive but slow. Internal cooling has the best ability to cool more rapidly but current devices are more invasive, costly and most are still not able to provide cooling within the rapid 5-min interval. Cardiopulmonary bypass and recirculating coolants can achieve the cooling rate but are currently extremely invasive and require a highly skilled team to implement. Future therapies may include phase-change coolants, such as microparticulate ice-saline slurries or evaporative cooling technologies specifically designed for human use. With continuing research and investment, methods for rapid cooling can be developed and will translate into saving lives. PMID:17605679

  3. Weld electrode cooling study

    NASA Astrophysics Data System (ADS)

    Masters, Robert C.; Simon, Daniel L.

    1999-03-01

    The U.S. auto/truck industry has been mandated by the Federal government to continuously improve their fleet average gas mileage, measured in miles per gallon. Several techniques are typically used to meet these mandates, one of which is to reduce the overall mass of cars and trucks. To help accomplish this goal, lighter weight sheet metal parts, with smaller weld flanges, have been designed and fabricated. This paper will examine the cooling characteristics of various water cooled weld electrodes and shanks used in resistance spot welding applications. The smaller weld flanges utilized in modern vehicle sheet metal fabrications have increased industry's interest in using one size of weld electrode (1/2 inch diameter) for certain spot welding operations. The welding community wants more data about the cooling characteristics of these 1/2 inch weld electrodes. To hep define the cooling characteristics, an infrared radiometer thermal vision system (TVS) was used to capture images (thermograms) of the heating and cooling cycles of several size combinations of weld electrodes under typical production conditions. Tests results will show why the open ended shanks are more suitable for cooling the weld electrode assembly then closed ended shanks.

  4. 7 CFR 917.14 - District.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... District. (g) Contra Costa District includes and consists of Contra Costa County. (h) Santa Clara District... Kings County. (p) Kern District includes and consists of that portion of Kern County west of the... AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE FRESH PEARS AND PEACHES GROWN...

  5. 7 CFR 917.14 - District.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... District. (g) Contra Costa District includes and consists of Contra Costa County. (h) Santa Clara District... Kings County. (p) Kern District includes and consists of that portion of Kern County west of the... AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE FRESH PEARS AND PEACHES GROWN...

  6. 7 CFR 917.14 - District.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... District. (g) Contra Costa District includes and consists of Contra Costa County. (h) Santa Clara District... Kings County. (p) Kern District includes and consists of that portion of Kern County west of the... and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE FRESH PEARS AND PEACHES GROWN...

  7. 7 CFR 917.14 - District.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... District. (g) Contra Costa District includes and consists of Contra Costa County. (h) Santa Clara District... Kings County. (p) Kern District includes and consists of that portion of Kern County west of the... and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE FRESH PEARS AND PEACHES GROWN...

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  12. 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...

  13. 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.

  14. 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.

  15. 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...

  16. 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...

  17. 33 CFR 1.01-50 - Delegation to District Commander, Seventeenth Coast Guard District.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., 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, 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...

  19. 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...

  20. 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

  1. Cool Flame Quenching

    NASA Technical Reports Server (NTRS)

    Pearlman, Howard; Chapek, Richard

    2001-01-01

    Cool flame quenching distances are generally presumed to be larger than those associated with hot flames, because the quenching distance scales with the inverse of the flame propagation speed, and cool flame propagation speeds are often times slower than those associated with hot flames. To date, this presumption has never been put to a rigorous test, because unstirred, non-isothermal cool flame studies on Earth are complicated by natural convection. Moreover, the critical Peclet number (Pe) for quenching of cool flames has never been established and may not be the same as that associated with wall quenching due to conduction heat loss in hot flames, Pe approx. = 40-60. The objectives of this ground-based study are to: (1) better understand the role of conduction heat loss and species diffusion on cool flame quenching (i.e., Lewis number effects), (2) determine cool flame quenching distances (i.e, critical Peclet number, Pe) for different experimental parameters and vessel surface pretreatments, and (3) understand the mechanisms that govern the quenching distances in premixtures that support cool flames as well as hot flames induced by spark-ignition. Objective (3) poses a unique fire safety hazard if conditions exist where cool flame quenching distances are smaller than those associated with hot flames. For example, a significant, yet unexplored risk, can occur if a multi-stage ignition (a cool flame that transitions to a hot flame) occurs in a vessel size that is smaller than that associated with the hot quenching distance. To accomplish the above objectives, a variety of hydrocarbon-air mixtures will be tested in a static reactor at elevated temperature in the laboratory (1g). In addition, reactions with chemical induction times that are sufficiently short will be tested aboard NASA's KC-135 microgravity (mu-g) aircraft. The mu-g results will be compared to a numerical model that includes species diffusion, heat conduction, and a skeletal kinetic mechanism, following the work on diffusion-controlled cool flames by Fairlie et,al., 2000.

  2. 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.

  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. 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.

  5. 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…

  6. 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.

  7. 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.

  8. 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.

  9. 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...

  10. 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.

  11. ELECTRON COOLING FOR RHIC.

    SciTech Connect

    BEN-ZVI,I.; AHRENS,L.; BRENNAN,M.; HARRISON,M.; KEWISCH,J.; MACKAY,W.; PEGGS,S.; ROSER,T.; SATOGATA,T.; TRBOJEVIC,D.; YAKIMENKO,V.

    2001-06-18

    We introduce plans for electron-cooling of the Relativistic Heavy Ion Collider (RHIC). This project has a number of new features as electron coolers go: It will cool 100 GeV/nucleon ions with 50 MeV electrons; it will be the first attempt to cool a collider at storage-energy; and it will be the first cooler to use a bunched beam and a linear accelerator as the electron source. The linac will be superconducting with energy recovery. The electron source will be based on a photocathode gun. The project is carried out by the Collider-Accelerator Department at BNL in collaboration with the Budker Institute of Nuclear Physics.

  12. 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.

  13. ELECTRON COOLING OF RHIC.

    SciTech Connect

    BEN-ZVI, I.; LITVINENKO, V.; BARTON, D.; ET AL.

    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.

  14. 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.

  15. 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.

  16. 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.

  17. Passive containment cooling system

    DOEpatents

    Billig, Paul F. (San Jose, CA); Cooke, Franklin E. (San Jose, CA); Fitch, James R. (San Jose, CA)

    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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. Superconductor rotor cooling system

    DOEpatents

    Gamble, Bruce B. (Wellesley, MA); Sidi-Yekhlef, Ahmed (Framingham, MA); Schwall, Robert E. (Northborough, MA); Driscoll, David I. (South Euclid, OH); Shoykhet, Boris A. (Beachwood, OH)

    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.

  3. Quantum thermodynamic cooling cycle.

    PubMed

    Palao, J P; Kosloff, R; Gordon, J M

    2001-11-01

    The quantum-mechanical and thermodynamic properties of a three-level molecular cooling cycle are derived. An inadequacy of earlier models is rectified in accounting for the spontaneous emission and absorption associated with the coupling to the coherent driving field via an environmental reservoir. This additional coupling need not be dissipative, and can provide a thermal driving force-the quantum analog of classical absorption chillers. The dependence of the maximum attainable cooling rate on temperature, at ultralow temperatures, is determined and shown to respect the recently established fundamental bound based on the second and third laws of thermodynamics. PMID:11736037

  4. 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.

  5. 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.

  6. Anomalous law of cooling.

    PubMed

    Lapas, Luciano C; Ferreira, Rogelma M S; Rub, 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. PMID:25770525

  7. 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.

  8. 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…

  9. Cooling Atomic Gases With Disorder

    NASA Astrophysics Data System (ADS)

    Paiva, Thereza; Khatami, Ehsan; Yang, Shuxiang; Rousseau, Valry; 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 Nel 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.

  10. Solar-powered cooling system

    DOEpatents

    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.

  11. Cooling Atomic Gases With Disorder.

    PubMed

    Paiva, Thereza; Khatami, Ehsan; Yang, Shuxiang; Rousseau, Valry; 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 MonteCarlo simulations, that we can approach the Nel 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

  12. 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.

  13. 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.

  14. Absorption heat pump in heating and cooling systems of buildings

    NASA Astrophysics Data System (ADS)

    Aho, I.

    This report focuses on the operation and applicability of absorption heat pumps (AHP) in building heating and cooling systems. Examples are presented on heating systems of residential buildings and a heating/cooling system of an office building. Despite the limitations of present AHP technology the examples assume AHPs which produce heat at an appropriate temperature level for each application. According to the calculations the primary energy saving potential of AHPs in building specific heat production is 20 to 40 percent. For AHPs coupled with district heating systems the primary energy saving potential can not be unambiguously defined because it is influenced by the production form of district heat, the influence of district heat demand on power generation etc. For the time being economical aspects limit the application potential of AHPs. The profitability of AHP investments is quite poor because of present energy prices, the price ratio of different energy forms and the high investment cost of AHP-systems. The environmental impact of AHPs depend on the fuel used in the generator. Using fuel oil or gas will decrease sulphur and particle emissions but might increase the emissions of NO(x) and hydrocarbons because of the smaller size of combustion units. CFC-emissions will be decreased because AHPs apply alternative refrigerants.

  15. 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.

  16. 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,

  17. 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.

  18. 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/.

  19. 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...

  20. 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.

  1. 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.

  2. Why Exercise Is Cool

    MedlinePLUS

    ... is cool! Reviewed by: Mary L. Gavin, MD Date reviewed: September 2015 previous 1 • 2 For Teens For Kids For Parents MORE ON THIS TOPIC It's Time to Play Be a Fit Kid What If I Don't Like Sports? How Can I Feel Better About My Body? What Girls Say About: Sports 5 Reasons Girls Should Play ...

  3. 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.

  4. Deep mine cooling system

    SciTech Connect

    Conan, J.

    1984-11-06

    A deep mine cooling system comprising a compressor supplied with air and rotatively driven by a motor and an expansion turbine supplied with compressed air from said compressor and driving an actuating unit, wherein the compressed air, after leaving the compressor but prior to reaching the expansion turbine, passes through a steam generator whose output provides the energy required to operate an absorption refrigeration machine used to cool utility water for mining, said compressed air on leaving the steam generator going to a first heat exchanger in which it yields calories to a water circuit comprising a second heat exchanger, said second heat exchanger giving off the calories absorbed by the water in the first heat exchanger to the air fed by the second heat exchanger to a drying cell that is regenerated by said air from the second heat exchanger, said drying cell being part of a set of two cells working in alternation, the other cell in the set receiving the compressed air from the first heat exchanger, such that the compressed air is fed to said expansion turbine after leaving said drying unit, and wherein the air exhausted from said expansion turbine is sent to a third heat exchanger after which it is distributed according to the needs of the mine, said third exchanger being traversed by the water collected in the mine, cooled in said exchanger and circulated upon leaving said exchanger to meet the cool water requirements of the mine.

  5. Elementary stochastic cooling

    SciTech Connect

    Tollestrup, A.V.; Dugan, G

    1983-12-01

    Major headings in this review include: proton sources; antiproton production; antiproton sources and Liouville, the role of the Debuncher; transverse stochastic cooling, time domain; the accumulator; frequency domain; pickups and kickers; Fokker-Planck equation; calculation of constants in the Fokker-Planck equation; and beam feedback. (GHT)

  6. 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.

  7. 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.

  8. Turbomachine rotor with improved cooling

    DOEpatents

    Hultgren, Kent Goran (Winter Park, FL); McLaurin, Leroy Dixon (Winter Springs, FL); Bertsch, Oran Leroy (Titusville, FL); Lowe, Perry Eugene (Oviedo, FL)

    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.

  9. Increasing Black Student Enrollment in Gifted Programs: An Exploration of the Pulaski County Special School District's Advocacy Efforts.

    ERIC Educational Resources Information Center

    Grantham, Tarek C.

    2003-01-01

    Results are presented of an advocacy event in Pulaski County, Arkansas, where one school district's efforts to desegregate their gifted program resulted in more black students enrolled. Different phases of a Gifted Program Advocacy Model are used to explain important components of the Pulaski County Special School District's advocacy efforts.

  10. 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

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. Acoustic leak detection for district heating systems

    SciTech Connect

    Kupperman, D.S.; Karvelas, D.E.

    1988-02-01

    An acoustic leak detection facility was completed and used to evaluate the capability of piezoelectric sensors, accelerometers, and capacitance microphones to detect and locate gas and water leaks in underground district heating and cooling (DHC) piping. Leak detection sensitivity and location capabilities for DHC systems were estimated from laboratory data and from data obtained from the underground DH system in Scranton, Pennsylvania, where acoustic background noise levels and acoustic signals from field-induced steam leaks were acquired. Acoustic detection of leaks with flow rates of less than 10 gpm is possible at a distance of several hundred meters, with a location accuracy of a few meters. Although steam leaks of comparable mass loss can be detected over a similar range with transducers mounted on the pipe outer wall, location accuracy of a few meters over this range may only be possible with transducers in direct contract with the steam. Intrusive sensors may also be necessary to detect and locate leaks in plastic pipe. 10 refs., 26 figs., 3 tabs.

  18. 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.

  19. 7 CFR 959.24 - Districts.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... of Cameron, Hidalgo, Starr, and Willacy in the State of Texas. District No. 4: (Wilson-Karnes) The Counties of DeWitt, Wilson, Atascosa, and Karnes in the State of Texas. District No. 5: (Winter Garden)...

  20. 7 CFR 959.24 - Districts.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... of Cameron, Hidalgo, Starr, and Willacy in the State of Texas. District No. 4: (Wilson-Karnes) The Counties of DeWitt, Wilson, Atascosa, and Karnes in the State of Texas. District No. 5: (Winter Garden)...