National Library of Energy BETA

Sample records for heating seasonal performance

  1. Radiant Barrier Performance during the Heating Season 

    E-Print Network [OSTI]

    Medina, M. A.; O'Neal, D. L.; Turner, W. D.

    1992-01-01

    . Extra null tests limit the number of radiant barrier tests that can be performed during short winter periods. However. nul1tesL~ were run during the months of June 1990 and April 1991 which confirmed that the houses still responded similarly...

  2. An experimental study of heating performance and seasonal modeling of vertical U-tube ground coupled heat pumps 

    E-Print Network [OSTI]

    Margo, Randal E.

    1992-01-01

    by circulating the secondary fluid through a pipe buried in the ground. In the heating mode, heat is extracted from the soil by the ground coil and is supplied to the conditioned space via the heat pump's refrigerant cycle. The GCHP is limited only... is the ASHRAE Design/Data Manual [Bose et al. , 1985], This manual also bases ground coil sizing on the line source solution. Deerman [1991] used the constant heat flux cylindrical source solution as a basis for a vertical U-tube simulation program. He used...

  3. Preliminary Analysis of a Solar Heat Pump System with Seasonal Storage for Heating and Cooling 

    E-Print Network [OSTI]

    Yu, G.; Chen, P.; Dalenback, J.

    2006-01-01

    For higher solar fraction and suitability for both heating and cooling, a solar heat pump system with seasonal storage was studied in this paper. The system scheme and control strategy of a solar heat pump system with seasonal storage for heating...

  4. State of Maine residential heating oil survey 2001-02 season summary [SHOPP

    SciTech Connect (OSTI)

    Elder, Betsy

    2002-05-22

    This, as the title implies, is a summary report of the price trends for heating oil, propane and kerosene heating fuels for the heating season.

  5. SEPEMO-Build SEasonal PErformance MOnitoring

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    in integrating heat pumps into its energy infrastructure (measured as additional heat pump installations per 10

  6. PERFORMANCE OF A STIRLING ENGINE POWERED HEAT ACTIVATED HEAT PUMP

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    PERFORMANCE OF A STIRLING ENGINE POWERED HEAT ACTIVATED HEAT PUMP W. D. C. Richards and W. L. Auxer General Electric Company Space Division King of Prussia, Pa. ABSTRACT A heat activated heat pump (HAHP by the heat pump effect. The Stirling engine/Rankine cycle refrigeration loop heat pump being developed would

  7. State Heating Oil & Propane Program. Final report 1997/98 heating season

    SciTech Connect (OSTI)

    Hunton, G.

    1998-06-01

    The following is a summary report of the New Hampshire Governor`s Office of Energy and Community Services (ECS) participation in the State Heating Oil and Propane Program (SHOPP) for the 1997/98 heating season. SHOPP is a cooperative effort, linking energy offices in East Coast and Midwest states, with the Department of Energy (DOE), Energy Information Administration (EIA) for the purpose of collecting retail price data for heating oil and propane. The program is funded by the participating state with a matching grant from DOE. SHOPP was initiated in response to congressional inquires into supply difficulties and price spikes of heating oil and propane associated with the winter of 1989/90. This is important to New Hampshire because heating oil controls over 55% of the residential heating market statewide. Propane controls 10% of the heating market statewide and is widely used for water heating and cooking in areas of the state where natural gas is not available. Lower installation cost, convenience, lower operating costs compared to electricity, and its perception as a clean heating fuel have all worked to increase the popularity of propane in New Hampshire and should continue to do so in the future. Any disruption in supply of these heating fuels to New Hampshire could cause prices to skyrocket and leave many residents in the cold.

  8. Ground Source Heat Pump Sub-Slab Heat Exchange Loop Performance in a Cold Climate

    SciTech Connect (OSTI)

    Mittereder, Nick; Poerschke, Andrew

    2013-11-01

    This report presents a cold-climate project that examines an alternative approach to ground source heat pump (GSHP) ground loop design. The innovative ground loop design is an attempt to reduce the installed cost of the ground loop heat exchange portion of the system by containing the entire ground loop within the excavated location beneath the basement slab. Prior to the installation and operation of the sub-slab heat exchanger, energy modeling using TRNSYS software and concurrent design efforts were performed to determine the size and orientation of the system. One key parameter in the design is the installation of the GSHP in a low-load home, which considerably reduces the needed capacity of the ground loop heat exchanger. This report analyzes data from two cooling seasons and one heating season.

  9. Study of Applications of Solar Heating Systems with Seasonal Storage in China 

    E-Print Network [OSTI]

    Yu, G.; Zhao, X.; Chen, P.

    2006-01-01

    In most northern parts of China, it is cold in winter and needs space heating in winter. This paper studies applications of solar heating systems with seasonal storage in China. A typical residential district was selected, ...

  10. Ground Source Heat Pump Sub-Slab Heat Exchange Loop Performance in a Cold Climate

    SciTech Connect (OSTI)

    Mittereder, N.; Poerschke, A.

    2013-11-01

    This report presents a cold-climate project that examines an alternative approach to ground source heat pump (GSHP) ground loop design. The innovative ground loop design is an attempt to reduce the installed cost of the ground loop heat exchange portion of the system by containing the entire ground loop within the excavated location beneath the basement slab. Prior to the installation and operation of the sub-slab heat exchanger, energy modeling using TRNSYS software and concurrent design efforts were performed to determine the size and orientation of the system. One key parameter in the design is the installation of the GSHP in a low-load home, which considerably reduces the needed capacity of the ground loop heat exchanger. This report analyzes data from two cooling seasons and one heating season. Upon completion of the monitoring phase, measurements revealed that the initial TRNSYS simulated horizontal sub-slab ground loop heat exchanger fluid temperatures and heat transfer rates differed from the measured values. To determine the cause of this discrepancy, an updated model was developed utilizing a new TRNSYS subroutine for simulating sub-slab heat exchangers. Measurements of fluid temperature, soil temperature, and heat transfer were used to validate the updated model.

  11. Performance Analysis of Air-Source Variable Speed Heat Pumps...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Performance Analysis of Air-Source Variable Speed Heat Pumps and Various Electric Water Heating Options Performance Analysis of Air-Source Variable Speed Heat Pumps and Various...

  12. Performance of a hybrid ground-coupled heat pump system

    SciTech Connect (OSTI)

    Phetteplace, G.; Sullivan, W.

    1998-10-01

    In climates dominated by air conditioning, a few so-called hybrid ground-coupled heat pump (GCHP) systems have been built. The hybrid system uses both a ground-coupled heat exchanger and a cooling tower, thereby reducing the amount of ground-coupling heat exchanger necessary. Although this concept has been shown to be feasible, the performance of such a system has not been measured in detail. Since it may be possible to achieve significant performance improvements in such systems by modifying the design and operational practices, detailed performance monitoring of such systems is needed. This paper describes a project that has been undertaken to collect performance data from a hybrid GCHP system at Fort Polk, LA. This paper presents performance data for a period of about 22 months, including data from portions of two heating and cooling seasons. The energy input to the GCHPs themselves will be presented, as well as the energy rejected to the ground in the cooling mode and that extracted from the ground in the heating mode. Energy flows in the cooling tower also will be addressed, along with the power consumption of the circulating pumps and the cooling tower.

  13. Heating Season Has Ended An Update On The Numbers

    E-Print Network [OSTI]

    . An Update On The Numbers The attached graphics illustrate electricity consumption over a number of years. As a reference point, electricity comprises 2/3rds of our total fuel costs. Consumption will vary from year)/May and September/October time-frames represent seasonal transition and an opportunity to save on fuel consumption

  14. Direct contact heat exchanger performance

    SciTech Connect (OSTI)

    Wahl, E. F.

    1981-03-12

    Although the final performance result of a DCHE is the cost of the net electricity produced, the best performance cannot be achieved without optimizing the components of the system as well as the whole system. Thus collection and analysis of data on the internal performance of the column assists in optimizing the operation of the particular column as well as in suggesting ways for improving the operation and design of future columns.

  15. Demonstration and Performance Monitoring of Foundation Heat Exchangers...

    Energy Savers [EERE]

    Demonstration and Performance Monitoring of Foundation Heat Exchangers in Low Load, High Performance Research Homes Demonstration and Performance Monitoring of Foundation Heat...

  16. Performance Optimization of an Irreversible Heat Pump with Variable-temperature Heat Reservoirs 

    E-Print Network [OSTI]

    Huang, Y.; Sun, D.

    2006-01-01

    An irreversible cycle model of a heat pump operating between two variable-temperature heat reservoirs is established and used to analyze the performance of the heat pump affected by heat resistances, heat leakage and internal dissipation...

  17. Status of Natural Gas Pipeline System Capacity Entering the 2000-2001 Heating Season

    Reports and Publications (EIA)

    2000-01-01

    This special report looks at the capabilities of the national natural gas pipeline network in 2000 and provides an assessment of the current levels of available capacity to transport supplies from production areas to markets throughout the United States during the upcoming heating season. It also examines how completion of currently planned expansion projects and proposed new pipelines would affect the network.

  18. Regional Variation in Residential Heat Pump Water Heater Performance...

    Energy Savers [EERE]

    Regional Variation in Residential Heat Pump Water Heater Performance in the United States Regional Variation in Residential Heat Pump Water Heater Performance in the United States...

  19. Performance of an Organic Rankine Cycle Waste Heat Recovery System...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Performance of an Organic Rankine Cycle Waste Heat Recovery System for Light Duty Diesel Engines Performance of an Organic Rankine Cycle Waste Heat Recovery System for Light Duty...

  20. ELECTRIC CO-HEATING: A METHOD FOR EVALUATING SEASONAL HEATING EFFICIENCIES AND HEAT LOSS RATES IN DWELLINGS

    E-Print Network [OSTI]

    Modera, M.P.

    2012-01-01

    the measured values for heat transmission and air leakagethe contribution by heat transmission alone through theheating efficiency, heat transmission coefficient and air

  1. DEVELOPMENT OF A HIGH PERFORMANCE COLD CLIMATE HEAT PUMP

    SciTech Connect (OSTI)

    Horton, W. Travis; Groll, Eckhard A.; Braun, James E.

    2014-06-01

    The primary goals of the proposed project were to develop, test, and evaluate a high performance and cost-effective vapor compression air-source heat pump for use in cold climate regions. Vapor compression heat pumps are a proven technology, and have been used for many years to meet heating requirements for buildings in residential, commercial, and industrial applications. However, in climate regions that experience very low outdoor ambient temperatures both the heating capacity and coefficient of performance (COP) of traditional air-source vapor compression heat pumps drops dramatically with a decrease in the outdoor air temperature. The efficiency of heat pumping equipment has improved substantially over the past 20 years; however, the efficiencies of the highest rated equipment on the market are approaching practical limits that cannot be surpassed without modifications to the basic cycle and possibly the use of additional hardware. In this report, three technologies to improve the efficiency of vapor compression systems are described. These are a) vapor injected compression, b) oil flooded compression and c) hybrid flow control of the evaporator. Compressor prototypes for both, oil flooded and vapor injected compression were developed by Emerson Climate Technologies. For the oil flooded compressor, the oil injection port location was optimized and an internal oil separator was added using several design iterations. After initial testing at Emerson Climate Technologies, further testing was done at Purdue University, and compressor models were developed. These models were then integrated into a system model to determine the achievable improvement of seasonal energy efficiency (SEER) for Minneapolis (Minnesota) climate. For the oil flooded compression, a 34% improvement in seasonal energy efficiency was found while a 21% improvement in seasonal energy efficiency ratio was found for the vapor injected compression. It was found that one benefit of both tested compression technologies is a lower discharge temperature, which allows for continued operation at lower ambient temperatures. A bin analysis of the vapor injected prototype cold climate heat pump predicts a 6% improvement in HSPF for Minneapolis. This improvement is mainly a result of the increased capacity of the system for active vapor injection. For the oil flooded system, a slightly larger performance improvement is predicted, in this case mostly caused by an increase in heating COP. Based on an economic analysis of these results, the maximum additional cost of the system changes, for the Minneapolis location, are $430 for the vapor injected system and $391 for the oil flooded system. These estimates assume that a 3-year simple payback period is accepted by the customer. For the hybrid flow control of evaporators, a new type of balancing valve was developed together with Emerson Climate technologies to reduce the cost of the control scheme. In contrast to conventional stepper motor valves, this valve requires less cables and can be driven by a cheaper output circuit on the control board. The correct valve size was determined in a dedicated test stand in several design iterations. The performance benefits of the hybrid control of the evaporator coil were determined for clean coil conditions as well as with partial blockage of the air inlet grille and under frosting conditions. For clean coil conditions, the benefits in terms of COP and capacity are negligible. However, significant benefits were noted for severely air-maldistributed operating conditions. For the H2-test, the maximum COP improvement of 17% along with a capacity improvement of nearly 40% was observed. Overall, the hybrid control scheme leads to a significant amount of performance improvement, if the air inlet conditions to the evaporator are maldistributed.

  2. SYSTEM PERFORMANCE OF A STIRLING ENGINE POWERED HEAT ACTIVATED HEAT PUMP

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    AUG 1979 SYSTEM PERFORMANCE OF A STIRLING ENGINE POWERED HEAT ACTIVATED HEAT PUMP W. D. Richards W The development of the first prototype heat activated heat pump (HAHP) jointly sponsored by the Gas Research to supplement the heating capacity in addition to the heat pump effect would enable a HAHP system

  3. Impact of Installation Faults on Heat Pump Performance

    SciTech Connect (OSTI)

    Hourahan, Mr. Glenn [Air Conditioning Contractors of America, Arlington, VA; Baxter, Van D [ORNL

    2015-01-01

    Numerous studies and surveys indicate that typically-installed HVAC equipment operate inefficiently and waste considerable energy due to varied installation errors (faults) such as improper refrigerant charge, incorrect airflow, oversized equipment, and leaky ducts. This article summarizes the results of a large United States (U.S.) experimental/analytical study (U.S. contribution to IEA HPP Annex 36) of the impact that different faults have on the performance of an air-source heat pump (ASHP) in a typical U.S. single-family house. It combines building effects, equipment effects, and climate effects in an evaluation of the faults impact on seasonal energy consumption through simulations of the house/ASHP pump system.

  4. Performance evaluation of low heat rejection engines

    SciTech Connect (OSTI)

    Sun, X.; Wang, W.G.; Bata, R.M. ); Gao, X. )

    1994-10-01

    Improving the performance of the Chinese B135 six-cylinder direct injection turbocharged and turbocompounded Low Heat Rejection Engine (LHRE) was based on experimental and analytical studies. The studies were primarily applied on a B1135 single-cylinder LHR engine and a conventional water-cooled B1135 single-cylinder engine. Performance of the B1135 LHRE was worse than that of the conventional B1135 due to a deterioration in the combustion process of the B1135 LHRE. The combustion process was improved and the fuel injection system was redesigned and applied to the B135 six-cylinder LHRE. The new design improved the performance of the LHRE and better fuel economy was realized by the thermal energy recovered from the exhaust gases by the turbocompounding system.

  5. Passive solar/earth sheltered office/dormitory cooling season thermal performance

    SciTech Connect (OSTI)

    Christian, J.

    1984-01-01

    Continuous detailed hourly thermal performance measurements have been taken since February 1982 in and around an occupied, underground, 4000 ft/sup 2/ office/dormitory building at the Oak Ridge National Laboratory in Oak Ridge, Tennessee. This building has a number of energy saving features which have been analyzed relative to their performance in a southeastern US climate and with respect to overall commercial building performance. This analysis documents cooling season performance, as well as effects of earth contact, interior thermal mass, an economizer cycle and interface of an efficient building envelope with a central three-ton heat pump. The Joint Institute Dormitory obtains a cooling energy savings of about 30% compared with an energy-efficient, above-grade structure and has the potential to save as much as 50%. The proper installation of the overhand, interior thermal mass, massive supply duct system, and earth contact team up to prevent summertime overheating. From May through September, this building cost a total of $300 (at 5.7 cents/kWh) to cool and ventilate 24 hours per day. Besides thermal performance of the building envelope, extensive comfort data was taken illustrating that at least 90% of the occupants are comfortable all of the time according to the PMV measurements.

  6. Performance of Integrated Hydronic Heating Systems.

    SciTech Connect (OSTI)

    BUTCHER,T.A.

    2007-12-20

    A variety of system configurations are used in North America to meet the heating and domestic hot water needs of single-family homes. This includes, for example: warm air furnaces with electric water heaters; boilers with integrated hot water coils; and boilers with 'indirect' hot water storage tanks. Integrated hydronic systems which provide both heat and hot water are more popular only in the Northeast and mid-Atlantic regions. For those making decisions about configurations of these integrated hydronic systems, including control options, little information is available concerning the annual energy cost implications of these decisions. This report presents results of a project to use a direct load emulation approach to measure the performance of hydronic systems, develop performance curves, and to provide decision tools to consumers. This is a laboratory measurement system involving direct energy input and output measurements under different load patterns. These results are then used to develop performance correlations for specific systems that can be used to predict energy use in specific applications. A wide range of system types have been tested under this project including conventional boilers with 'tankless' internal coils for domestic hot water production, boilers with indirect external storage tanks, tank type water heaters which may also be used for space heating, condensing oil- and gas-fired systems, and systems with custom control features. It is shown that low load and idle energy losses can have a very large impact on the total annual energy use and that the potential energy savings associated with replacing old equipment with newer, high efficiency equipment with low losses at idle or low load can be in the 25% range. These savings are larger than simple combustion efficiency measurements would indicate.

  7. Performance of a drain-back solar heating and hot water system with auxiliary heat pump. Final report

    SciTech Connect (OSTI)

    Karaki, S.

    1984-03-01

    The principal objective of the project was to test and evaluate the BNL collectors in a space heating system. When the BNL collectors delaminated under stagnation conditions, they were replaced with the Chamberlain collectors which were previously used on solar house III, and tests were continued to evaluate performance of a drain-back system. Results leading to the following conclusions are discussed. (1) The Chamberlain collectors have deteriorated in performance compared to previous seasons. Where daily efficiency of 41% were attained in 1978 to 1979 and 1979 to 1980, efficiency was 37%. System efficiency of 29% compares to 30% in prior years. (2) Solar contribution to DHW heating is low, and is probably the result of the artificially imposed load profile and the low recovery rate of the double-wall heat exchanger. (3) System efficiency can be improved by reducing thermal losses from storage.

  8. BEMS-Assisted Seasonal Functional Performance Testing in the Initial Commissioning of Kista Entre and Katsan 

    E-Print Network [OSTI]

    Isakson, P.; Wetterstrom, P.; Carling, P.

    2004-01-01

    detect and diagnose energy and other performance problems with building operations [1]. However, in Sweden the assessment of seasonal performance in commissioning typically uses trend-data from only a few days. Our hypothesis is that monitoring...-ASSISTED SEASONAL FUNCTIONAL PERFORMANCE TESTING IN THE INITIAL COMMISSIONING OF KISTA ENTRÉ AND KATSAN Per Isakson*, Per Wetterström** and Pär Carling*** * Building Sciences KTH, Stockholm SWEDEN. per.isakson@byv.kth.se ** Vasakronan, Stockholm, SWEDEN...

  9. Cooling season performance of an earth-sheltered office/dormitory building in Oak Ridge, Tennessee

    SciTech Connect (OSTI)

    Christian, J.E.

    1984-07-01

    Detailed hourly measurements taken in and around an underground office-dormitory building for two summers document energy savings; whole building-component interface problems; and specific cooling contributions from earth contact, interior thermal mass, and an economizer. The Joint Institute Dormitory (JID) saves about 30% compared with well-built above-grade buildings in a climate typical of Oak Ridge, Tennessee, and has the potential to save as much as 50%. The detailed measurements, which include extensive thermal comfort data, indicate that at least 90% of the occupants are comfortable all of the time. The thermal performance measurements and analysis determine that the peak cooling requirement of this building is 50% less than that of well-built above-grade structures, permitting a cost savings on installed cooling capacity. The dominant building components contributing to the good thermal performance are the structural thermal mass, the earth-covered roof, and the earth contact provided by the bermed walls and slab floor. The 372-m/sup 2/ (4000 gross ft/sup 2/) building used about $300 (at 5.7 cents/kWh) to cool and ventilate from May through September. Eliminating a number of building design and construction anomalies could improve the whole-building performance and reduce the seasonal cooling cost another $85. Close examination of the thermal performance of this building revealed that a very efficient heat pump and thermally sound envelope do not necessarily produce otpimum performance without careful attention given to component interface details. 8 references, 24 figures, 12 tables.

  10. FINAL REPORT A HIGH SEASONAL

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    #12;'I MTI 79TR68 FINAL REPORT A HIGH SEASONAL PERFORMANCE FACTOR GAS HEAT PUMP FOR THE NORTH Model Gas Heat Pump ......... 11-4 11.4 CNG Typical Weather Year Selection Method. . . . 11-5 11 of the subject gas-fueled heat pump under development in comparison with other equipment which

  11. Interannual Changes in Seasonal Ground Freezing and Near-surface Heat Flow Beneath Bottom-fast Ice in the Near-shore Zone, Mackenzie Delta, NWT, Canada

    E-Print Network [OSTI]

    Moorman, Brian

    Interannual Changes in Seasonal Ground Freezing and Near-surface Heat Flow Beneath Bottom-fast Ice Resources Canada, Dartmouth, Nova Scotia, Canada ABSTRACT Interannual changes in seasonal ground freezing. KEY WORDS: seasonal ground freezing; permafrost; bottom-fast ice; Mackenzie Delta INTRODUCTION Arctic

  12. Field monitoring and evaluation of a residential gas-engine-driven heat pump: Volume 2, Heating season

    SciTech Connect (OSTI)

    Miller, J.D.

    1995-11-01

    The Federal Government is the largest single energy consumer in the United States; consumption approaches 1.5 quads/year of energy (1 quad = 10{sup 15} Btu) at a cost valued at nearly $10 billion annually. The US Department of Energy (DOE) Federal Energy Management Program (FEMP) supports efforts to reduce energy use and associated expenses in the Federal sector. One such effort, the New Technology Demonstration Program (NTDP), seeks to evaluate new energy-saving US technologies and secure their more timely adoption by the US Government. Pacific Northwest Laboratory (PNL) is one of four DOE national multiprogram laboratories that participate in the NTDP by providing technical expertise and equipment to evaluate new, energy-saving technologies being studied and evaluated under that program. This two-volume report describes a field evaluation that PNL conducted for DOE/FEMP and the US Department of Defense (DoD) Strategic Environmental Research and Development Program (SERDP) to examine the performance of a candidate energy-saving technology -- a gas-engine-driven heat pump. The unit was installed at a single residence at Fort Sam Houston, a US Army base in San Antonio, Texas, and the performance was monitored under the NTDP. Participating in this effort under a Cooperative Research and Development Agreement (CRADA) were York International, the heat pump manufacturer; Gas Research Institute (GRI), the technology developer; City Public Service of San Antonio, the local utility; American Gas Cooling Center (AGCC); Fort Sam Houston; and PNL.

  13. Performance Evaluation of a Retrofit Industrial Heat Pump 

    E-Print Network [OSTI]

    Wagner, J.R.

    1986-01-01

    , and paper mill in the Gulf Coast. In most cases the software to perform these analyses can be used at no charge by contacting the local electrical utility that serves your plant. PERFORMANCE EVALUATION OF A RETROFIT INDUSTRIAL HEAT PUMP Joseph R. Wagner... Mechanical Technology Inc. Latham, NY This paper discusses the performance and economics of a mechanical vapor com? pression (MVC) heat pump that was retrofitted to a single-effect, recirculating? type evaporator. The evaporator is used for reducing...

  14. XI. DIFFUSEGLOBAL CORRELATIONS: SEASONAL VARIATIONS Estimating the performance of a solar system

    E-Print Network [OSTI]

    Oregon, University of

    39 XI. DIFFUSE­GLOBAL CORRELATIONS: SEASONAL VARIATIONS Estimating the performance of a solar system requires an accurate assessment of incident solar radiation. Ordinarily, solar radiation-9]. In the previous section we presented a one- parameter correlation study using direct and global data from our

  15. Water-to-Air Heat Pump Performance with Lakewater 

    E-Print Network [OSTI]

    Kavanaugh, S.; Pezent, M. C.

    1989-01-01

    The performance of water-to-air heat pumps using lakewater as the heat source and sink has been investigated. Direct cooling with deep lakewater has also been considered. Although the emphasis of the work was with southern lakes, many results also...

  16. Comparative Performance of Heat Pumps and R&D Requirements 

    E-Print Network [OSTI]

    Ally, M. R.

    1987-01-01

    PERFORMANCE OF HEAT PUMPS AND R&D REQUIREMENTS M. R. ALLY Research Staff Member Energy Divisi.on Oak Ridge National Laboratory Oak Ridge, Tennessee INTRODUCTION One of the major programs conducted by the U.S. Department of Energy's Office... of Industrial Programs is the Industrial Heat Pump Program. The objective of this program is to develop and advance heat pump technology to help American industry use its energy resources more efficiently. It involves using heat pumps in a role of both...

  17. The effects of outdoor heat exchanger hydrophobic treatment on the performance of an air source heat pump 

    E-Print Network [OSTI]

    Parker, Brandon DeWayne

    1995-01-01

    The effects of outdoor heat exchanger hydrophobic treatment on the performance of an air source heat pump were investigated. The base case tests used a bare aluminum outdoor heat exchanger in the experimental setup. The base case test results were...

  18. Laboratory Performance Evaluation of Residential Integrated Heat Pump Water Heaters

    SciTech Connect (OSTI)

    Sparn, B.; Hudon, K.; Christensen, D.

    2014-06-01

    This paper explores the laboratory performance of five integrated Heat Pump Water Heaters (HPWHs) across a wide range of operating conditions representative of U.S. climate regions. HPWHs are expected to provide significant energy savings in certain climate zones when compared to typical electric resistance water heaters. Results show that this technology is a viable option in most climates, but differences in control schemes and design features impact the performance of the units tested. Tests were conducted to map heat pump performance across the operating range and to determine the logic used to control the heat pump and the backup electric heaters. Other tests performed include two unique draw profile tests, reduced air flow performance tests and the standard DOE rating tests. The results from all these tests are presented here for all five units tested. The results of these tests will be used to improve the EnergyPlus heat pump water heater for use in BEopt™ whole-house building simulations.

  19. Laboratory Performance Evaluation of Residential Integrated Heat Pump Water Heaters

    SciTech Connect (OSTI)

    Sparn, B.; Hudon, K.; Christensen, D.

    2014-06-01

    This paper explores the laboratory performance of five integrated Heat Pump Water Heaters (HPWHs) across a wide range of operating conditions representative of US climate regions. HPWHs are expected to provide significant energy savings in certain climate zones when compared to typical electric resistance water heaters. Results show that this technology is a viable option in most climates, but differences in control schemes and design features impact the performance of the units tested. Tests were conducted to map heat pump performance across the operating range and to determine the logic used to control the heat pump and the backup electric heaters. Other tests performed include two unique draw profile tests, reduced air flow performance tests and the standard DOE rating tests. The results from all these tests are presented here for all five units tested. The results of these tests will be used to improve the EnergyPlus heat pump water heater for use in BEopt(tm) whole-house building simulations.

  20. Performance limits of multilevel and multipartite quantum heat machines

    E-Print Network [OSTI]

    Wolfgang Niedenzu; David Gelbwaser-Klimovsky; Gershon Kurizki

    2015-08-12

    We present the general theory of a quantum heat machine based on an $N$-level system (working medium) whose $N-1$ excited levels are degenerate, a prerequisite for steady-state interlevel coherence. Our goal is to find out: To what extent is coherence in the working medium an asset for heat machines? The performance bounds of such a machine are common to (reciprocating) cycles that consist of consecutive strokes and continuous cycles wherein the periodically driven system is constantly coupled to cold and hot heat baths. Intriguingly, we find that the machine's performance strongly depends on the relative orientations of the transition-dipole vectors in the system. Perfectly aligned (parallel) transition dipoles allow for steady-state coherence effects, but also give rise to dark states, which hinder steady-state thermalization and thus reduce the machine's performance. Similar thermodynamic properties hold for $N$ two-level atoms conforming to the Dicke model. We conclude that level degeneracy, but not necessarily coherence, is a thermodynamic resource, equally enhancing the heat currents and the power output of the heat machine. By contrast, the efficiency remains unaltered by this degeneracy and adheres to the Carnot bound.

  1. Decision making performance in a combined heat and noise environment 

    E-Print Network [OSTI]

    Pope, Mattison Scott

    1993-01-01

    This thesis was performed in order to determine the ability to make correct decisions when presented with two stressors under four conditions: controlled (70'F and 65 dBA); heat (105'F and 65 dBA); noise (70'F and 83 dBA); ...

  2. Performance of Gas-Engine Driven Heat Pump Unit

    SciTech Connect (OSTI)

    Abdi Zaltash; Randy Linkous; Randall Wetherington; Patrick Geoghegan; Ed Vineyard; Isaac Mahderekal; Robert Gaylord

    2008-09-30

    Air-conditioning (cooling) for buildings is the single largest use of electricity in the United States (U.S.). This drives summer peak electric demand in much of the U.S. Improved air-conditioning technology thus has the greatest potential impact on the electric grid compared to other technologies that use electricity. Thermally-activated technologies (TAT), such as natural gas engine-driven heat pumps (GHP), can provide overall peak load reduction and electric grid relief for summer peak demand. GHP offers an attractive opportunity for commercial building owners to reduce electric demand charges and operating expenses. Engine-driven systems have several potential advantages over conventional single-speed or single-capacity electric motor-driven units. Among them are variable speed operation, high part load efficiency, high temperature waste heat recovery from the engine, and reduced annual operating costs (SCGC 1998). Although gas engine-driven systems have been in use since the 1960s, current research is resulting in better performance, lower maintenance requirements, and longer operating lifetimes. Gas engine-driven systems are typically more expensive to purchase than comparable electric motor-driven systems, but they typically cost less to operate, especially for commercial building applications. Operating cost savings for commercial applications are primarily driven by electric demand charges. GHP operating costs are dominated by fuel costs, but also include maintenance costs. The reliability of gas cooling equipment has improved in the last few years and maintenance requirements have decreased (SCGC 1998, Yahagi et al. 2006). Another advantage of the GHP over electric motor-driven is the ability to use the heat rejected from the engine during heating operation. The recovered heat can be used to supplement the vapor compression cycle during heating or to supply other process loads, such as water heating. The use of the engine waste heat results in greater operating efficiency compared to conventional electric motor-driven units (SCGC 1998). In Japan, many hundreds of thousands of natural gas-driven heat pumps have been sold (typically 40,000 systems annually) (Yahagi et al. 2006). The goal of this program is to develop dependable and energy efficient GHPs suitable for U.S. commercial rooftop applications (the single largest commercial product segment). This study describes the laboratory performance evaluation of an integrated 10-ton GHP rooftop unit (a 900cc Daihatsu-Aisin natural gas engine) which uses R410A as the refrigerant (GEDAC No.23). ORNL Thermally-Activated Heat Pump (TAHP) Environmental Chambers were used to evaluate this unit in a controlled laboratory environment.

  3. Michigan residential No. 2 fuel oil and propane price survey for the 1990/91 heating season. Final report

    SciTech Connect (OSTI)

    Not Available

    1991-10-01

    This report summarizes the results of a survey of home heating oil and propane prices over the 1990/1991 heating season in Michigan. The survey was conducted under a cooperative agreement between the State of Michigan, Michigan Public Service Commission and the US Department of Energy (DOE), Energy Information Administration (EIA), and was funded by a grant from EIA. From October 1990 through May 1991, participating dealers/distributions were called and asked for their current residential retail prices of No. 2 home heating oil and propane. This information was then transmitted to the EIA, bi-monthly using an electronic reporting system called Petroleum Data Reporting Option (PEDRO). The survey was conducted using a sample provided by EIA of home heating oil and propane retailers which supply Michigan households. These retailers were contacted the first and third Mondays of each month. The sample was designed to account for distributors with different sales volumes, geographic distributions and sources of primary supply. It should be noted that this simple is different from the sample used in prior year surveys.

  4. Michigan residential No. 2 fuel oil and propane price survey for the 1990/91 heating season

    SciTech Connect (OSTI)

    Not Available

    1991-10-01

    This report summarizes the results of a survey of home heating oil and propane prices over the 1990/1991 heating season in Michigan. The survey was conducted under a cooperative agreement between the State of Michigan, Michigan Public Service Commission and the US Department of Energy (DOE), Energy Information Administration (EIA), and was funded by a grant from EIA. From October 1990 through May 1991, participating dealers/distributions were called and asked for their current residential retail prices of No. 2 home heating oil and propane. This information was then transmitted to the EIA, bi-monthly using an electronic reporting system called Petroleum Data Reporting Option (PEDRO). The survey was conducted using a sample provided by EIA of home heating oil and propane retailers which supply Michigan households. These retailers were contacted the first and third Mondays of each month. The sample was designed to account for distributors with different sales volumes, geographic distributions and sources of primary supply. It should be noted that this simple is different from the sample used in prior year surveys.

  5. Performance of Horizontal Field Earth-Coupled Heat Pumps 

    E-Print Network [OSTI]

    Abbott, C. A.

    1986-01-01

    An alternative to traditional methods of residential heating and cooling is the heat pump. However, heat pumps which use the outside air as a heat source/sink become inefficient during the periods of highest demand. Another possible heat source...

  6. Cooling and Heating Season Impacts of Right-Sizing of Fixed- and Variable-Capacity Heat Pumps With Attic and Indoor Ductwork

    SciTech Connect (OSTI)

    Cummings, James; Withers, Charles; Kono, Jamie

    2015-06-01

    ?A new generation of central, ducted variable-capacity heat pump systems has come on the market, promising very high cooling and heating efficiency. They are controlled differently than standard fixed-capacity systems. Instead of cycling on at full capacity and then cycling off when the thermostat is satisfied, they vary their cooling and heating output over a wide range (approximately 40% - 118% of nominal full capacity), thus staying 'on' for 60% - 100% more hours per day compared to fixed -capacity systems. Experiments in this research examined the performance of 2-ton and 3-ton fixed- and variable-capacity systems and the impacts of system oversizing.

  7. Field Performance of Heat Pump Water Heaters in the Northeast

    SciTech Connect (OSTI)

    Shapiro, C.; Puttagunta, S.

    2013-08-01

    Heat pump water heaters (HPWHs) are finally entering the mainstream residential water heater market. Potential catalysts are increased consumer demand for higher energy efficiency electric water heating and a new Federal water heating standard that effectively mandates use of HPWHs for electric storage water heaters with nominal capacities greater than 55 gallons. When compared to electric resistance water heating, the energy and cost savings potential of HPWHs is tremendous. Converting all electric resistance water heaters to HPWHs could save American consumers 7.8 billion dollars annually ($182 per household) in water heating operating costs and cut annual residential source energy consumption for water heating by 0.70 quads. Steven Winter Associates, Inc. embarked on one of the first in situ studies of these newly released HPWH products through a partnership with two sponsoring electric utility companies, National Grid and NSTAR, and one sponsoring energy efficiency service program administrator, Cape Light Compact. Recent laboratory studies have measured performance of HPWHs under various operating conditions, but publicly available field studies have not been as available. This evaluation attempts to provide publicly available field data on new HPWHs by monitoring the performance of three recently released products (General Electric GeoSpring(tm), A.O. Smith Voltex(r), and Stiebel Eltron Accelera(r)300). Fourteen HPWHs were installed in Massachusetts and Rhode Island and monitored for over a year. Of the 14 units, ten were General Electric models (50 gallon units), two were Stiebel Eltron models (80 gallon units), and two were A.O. Smith models (one 60-gallon and one 80-gallon unit).

  8. A SIMULATION MODEL FOR THE PERFORMANCE ANALYSIS OF ROOF POND SYSTEMS FOR HEATING AND COOLING

    E-Print Network [OSTI]

    Tavana, Medhi

    2011-01-01

    on Heating Performance of Roof Pond XSL803-6664 Fig. 4.on Heating Performance of Roof Pond Phoenix, Arizona Auguston Cooling Performance of Roof Pond HOur of the doy (solar

  9. Demand Response Performance of GE Hybrid Heat Pump Water Heater

    SciTech Connect (OSTI)

    Widder, Sarah H.; Parker, Graham B.; Petersen, Joseph M.; Baechler, Michael C.

    2013-07-01

    This report describes a project to evaluate and document the DR performance of HPWH as compared to ERWH for two primary types of DR events: peak curtailments and balancing reserves. The experiments were conducted with GE second-generation “Brillion”-enabled GeoSpring hybrid water heaters in the PNNL Lab Homes, with one GE GeoSpring water heater operating in “Standard” electric resistance mode to represent the baseline and one GE GeoSpring water heater operating in “Heat Pump” mode to provide the comparison to heat pump-only demand response. It is expected that “Hybrid” DR performance, which would engage both the heat pump and electric elements, could be interpolated from these two experimental extremes. Signals were sent simultaneously to the two water heaters in the side-by-side PNNL Lab Homes under highly controlled, simulated occupancy conditions. This report presents the results of the evaluation, which documents the demand-response capability of the GE GeoSpring HPWH for peak load reduction and regulation services. The sections describe the experimental protocol and test apparatus used to collect data, present the baselining procedure, discuss the results of the simulated DR events for the HPWH and ERWH, and synthesize key conclusions based on the collected data.

  10. Performance of Variable Capacity Heat Pumps in a Mixed Humid Climate

    SciTech Connect (OSTI)

    Munk, Jeffrey D [ORNL; Gehl, Anthony C [ORNL; Jackson, Roderick K [ORNL

    2012-04-01

    Variable capacity heat pumps represent the next wave of technology for heat pumps. In this report, the performance of two variable capacity heat pumps (HPs) is compared to that of a single or two stage baseline system. The units were installed in two existing research houses located in Knoxville, TN. These houses were instrumented to collect energy use and temperature data while both the baseline systems and variable capacity systems were installed. The homes had computer controlled simulated occupancy, which provided consistent schedules for hot water use and lighting. The temperature control and energy use of the systems were compared during both the heating and cooling seasons. Multiple linear regression models were used along with TMY3 data for Knoxville, TN in order to normalize the effect that the outdoor air temperature has on energy use. This enables a prediction of each system's energy use over a year with the same weather. The first system was a multi-split system consisting of 8 indoor units and a single outdoor unit. This system replaced a 16 SEER single stage HP with a zoning system, which served as the baseline. Data was collected on the baseline system from August 2009 to December 2010 and on the multi-split system from January 2011 to January 2012. Soon after the installation of the multi-split system, some of the smaller rooms began over-conditioning. This was determined to be caused by a small amount of continuous refrigerant flow to all of the indoor units when the outdoor unit was running regardless of whether they were calling for heat. This, coupled with the fact that the indoor fans run continuously, was providing enough heat in some rooms to exceed the set point. In order to address this, the indoor fans were disabled when not actively heating per the manufacturer's recommendation. Based on the measured data, the multi-split system was predicted to use 40% more energy in the heating season and 16% more energy in the cooling season than the baseline system, for the typical meteorological year weather data. The AHRI ratings indicated that the baseline system would perform slightly better than the multi-split system, but not by as large of a margin as seen in this study. The multi-split system was able to maintain more consistent temperature throughout the house than the baseline system, but it did allow relative humidity levels to increase above 60% in the summer. The second system was a split system with an inverter driven compressor and a single ducted air handler. This unit replaced a 16 SEER two stage HP with a zoning system. Data was collected on the baseline system from July 2009 to November 2010 and on the ducted inverter system from December 2010 to January 2012. The ducted inverter system did not offer a zone controller, so it functioned as a single zone system. Due to this fact, the registers had to be manually adjusted in order to better maintain consistent temperatures between the two levels of the house. The predicted heating season energy use for the ducted inverter system, based on the measured energy use, was 30% less than that of the baseline system for the typical meteorological year. However, the baseline system was unable to operate in its high stage due to a wiring issue with the zone controller. This resulted in additional resistance heat use during the winter and therefore higher energy use than would be expected in a properly performing unit. The AHRI ratings would indicate that the baseline system would use less energy than the ducted inverter system, which is opposite to the results of this study. During the cooling season, the ducted inverter system was predicted to use 23% more energy than the baseline system during the typical meteorological year. This is also opposite of the results expected by comparing the AHRI ratings. After a detailed comparison of the ducted inverter system's power use compared to that of a recently installed identical system at a retro-fit study house, there is concern that the unit is not operating as intended. The power use and cycles indicate t

  11. Commissioning Tools for Heating/Cooling System in Residence - Verification of Floor Heating System and Room Air Conditioning System Performance 

    E-Print Network [OSTI]

    Miura, H.; Hokoi, S.; Iwamae, A.; Umeno, T.; Kondo, S.

    2004-01-01

    Tools of evaluating the performance of floor heating and room air conditioner are examined as a commissioning tool. Simple method is needed to check these performance while in use by residents, because evaluation currently requires significant time...

  12. Seasonal versus Episodic Performance Evaluation for an Eulerian Photochemical Air Quality Model

    SciTech Connect (OSTI)

    Jin, Ling; Brown, Nancy J.; Harley, Robert A.; Bao, Jian-Wen; Michelson, Sara A; Wilczak, James M

    2010-04-16

    This study presents detailed evaluation of the seasonal and episodic performance of the Community Multiscale Air Quality (CMAQ) modeling system applied to simulate air quality at a fine grid spacing (4 km horizontal resolution) in central California, where ozone air pollution problems are severe. A rich aerometric database collected during the summer 2000 Central California Ozone Study (CCOS) is used to prepare model inputs and to evaluate meteorological simulations and chemical outputs. We examine both temporal and spatial behaviors of ozone predictions. We highlight synoptically driven high-ozone events (exemplified by the four intensive operating periods (IOPs)) for evaluating both meteorological inputs and chemical outputs (ozone and its precursors) and compare them to the summer average. For most of the summer days, cross-domain normalized gross errors are less than 25% for modeled hourly ozone, and normalized biases are between {+-}15% for both hourly and peak (1 h and 8 h) ozone. The domain-wide aggregated metrics indicate similar performance between the IOPs and the whole summer with respect to predicted ozone and its precursors. Episode-to-episode differences in ozone predictions are more pronounced at a subregional level. The model performs consistently better in the San Joaquin Valley than other air basins, and episodic ozone predictions there are similar to the summer average. Poorer model performance (normalized peak ozone biases <-15% or >15%) is found in the Sacramento Valley and the Bay Area and is most noticeable in episodes that are subject to the largest uncertainties in meteorological fields (wind directions in the Sacramento Valley and timing and strength of onshore flow in the Bay Area) within the boundary layer.

  13. Improving Process Heating System Performance: A Sourcebook for...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    in Process Heating Systems Save Energy Now in Your Process Heating Systems ITP Metal Casting: Advanced Melting Technologies: Energy Saving Concepts and Opportunities for the...

  14. Performance Analysis of Air-Source Variable Speed Heat Pumps...

    Broader source: Energy.gov (indexed) [DOE]

    Overview * Electric Water Heating Options - Conventional Electric Water Heaters - Heat Pump Water Heaters * Air-Source * Ground-Source - Solar Thermal Water Heater * Variable...

  15. Natural Refrigerant High-Performance Heat Pump for Commercial...

    Broader source: Energy.gov (indexed) [DOE]

    (DE-FOA-0000823) Project Objective This project aims to develop a regenerative air source heat pump for commercial and industrial heating, ventilation, and air conditioning (HVAC)...

  16. Performance of evacuated tubular solar collectors in a residential heating and cooling system. Final report, 1 October 1978-30 September 1979

    SciTech Connect (OSTI)

    Duff, W.S.; Loef, G.O.G.

    1981-03-01

    Operation of CSU Solar House I during the heating season of 1978-1979 and during the 1979 cooling season was based on the use of systems comprising an experimental evacuated tubular solar collector, a non-freezing aqueous collection medium, heat exchange to an insulated conventional vertical cylindrical storage tank and to a built-up rectangular insulated storage tank, heating of circulating air by solar heated water and by electric auxiliary in an off-peak heat storage unit, space cooling by lithium bromide absorption chiller, and service water heating by solar exchange and electric auxiliary. Automatic system control and automatic data acquisition and computation are provided. This system is compared with others evaluated in CSU Solar Houses I, II and III, and with computer predictions based on mathematical models. Of the 69,513 MJ total energy requirement for space heating and hot water during a record cold winter, solar provided 33,281 MJ equivalent to 48 percent. Thirty percent of the incident solar energy was collected and 29 percent was delivered and used for heating and hot water. Of 33,320 MJ required for cooling and hot water during the summer, 79 percent or 26,202 MJ were supplied by solar. Thirty-five percent of the incident solar energy was collected and 26 percent was used for hot water and cooling in the summer. Although not as efficient as the Corning evacuated tube collector previously used, the Philips experimental collector provides solar heating and cooling with minimum operational problems. Improved performance, particularly for cooling, resulted from the use of a very well-insulated heat storage tank. Day time (on-peak) electric auxiliary heating was completely avoided by use of off-peak electric heat storage. A well-designed and operated solar heating and cooling system provided 56 percent of the total energy requirements for heating, cooling, and hot water.

  17. Measured Performance of a Low Temperature Air Source Heat Pump

    SciTech Connect (OSTI)

    R.K. Johnson

    2013-09-01

    A 4-ton Low Temperature Heat Pump (LTHP) manufactured by Hallowell International was installed in a residence near New Haven, Connecticut and monitored over two winters of operation. After attending to some significant service issues, the heat pump operated as designed. This report should be considered a review of the dual compressor “boosted heat pump” technology. The Low Temperature Heat Pump system operates with four increasing levels of capacity (heat output) as the outdoor temperature drops.

  18. PERFORMANCE OF A SINGLE-ROW HEAT EXCHANGER AT LOW IN-TUBE FLOW RATES

    E-Print Network [OSTI]

    Sen, Mihir

    PERFORMANCE OF A SINGLE-ROW HEAT EXCHANGER AT LOW IN-TUBE FLOW RATES A Thesis Submitted April 1995 #12;PERFORMANCE OF A SINGLE-ROW HEAT EXCHANGER AT LOW IN-TUBE FLOW RATES by Xiangwei Zhao Abstract The steady and time-dependentbehavior of a single-row heat exchanger with water and air in the in

  19. NREL Evaluates Performance of Heat Pump Water Heaters (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-02-01

    NREL evaluates energy savings potential of heat pump water heaters in homes throughout all U.S. climate zones.

  20. Management and Control for Optimal Performance of the Heating Substation 

    E-Print Network [OSTI]

    Yang, J.

    2006-01-01

    With the development of the scale of central heating, a higher managing level is needed for the heating substation. How to economize the more energy is the first factor that managers need to consider while ensuring the comfort of the heating...

  1. Ground and Water Source Heat Pump Performance and Design for Southern Climates 

    E-Print Network [OSTI]

    Kavanaugh, S.

    1988-01-01

    Ground and water source heat pump systems have very attractive performance characteristics when properly designed and installed. These systems typically consist of a water-to-air or water-to-water heat pump linked to a closed loop vertical...

  2. An Analysis of Efficiency Improvements in Residential Sized Heat Pumps and Central Air Conditioners 

    E-Print Network [OSTI]

    O'Neal, D. L.; Boecker, C. L.; Penson, S. B.

    1986-01-01

    This report summarizes: (1) the performance improvements possible for central air conditioners and heat pumps using conventional design improvements, (2) the development of a methodology for estimating the seasonal performance of variable speed heat...

  3. High-Performance Refrigerator Using Novel Rotating Heat Exchanger...

    Energy Savers [EERE]

    Cooler relative to current heat exchanger technology are additional refrigerated space, noise reduction, and fouling reduction. Additional refrigerated volume realized by the more...

  4. Laboratory Performance Evaluation of Residential Integrated Heat Pump Water Heaters

    SciTech Connect (OSTI)

    Sparn, B.; Hudon, K.; Christensen, D.

    2011-09-01

    This report discusses how a significant opportunity for energy savings is domestic hot water heating, where an emerging technology has recently arrived in the U.S. market: the residential integrated heat pump water heater. A laboratory evaluation is presented of the five integrated HPWHs available in the U.S. today.

  5. Exergy Optimized Wastewater Heat Recovery: Minimizing Losses and Maximizing Performance 

    E-Print Network [OSTI]

    Meggers, F.

    2008-01-01

    output to minimize the temperature lift required by a heat pump. This would create an integrated low exergy space and water heating system. The project theory is a part of the IEA ECBCS Annex 49, and also collaboration has been setup with Geberit AG...

  6. PERFORMANCE ANALYSIS OF A RESIDENTIAL GROUND SOURCE HEAT PUMP SYSTEM WITH ANTIFREEZE SOLUTION

    E-Print Network [OSTI]

    freezing in the heat pump. The antifreeze mixture type and concentration has a number of implications for the design and performance of the system. These include the required ground loop heat exchanger length, and the first cost of the system. For example, the required ground loop heat exchanger length and first cost

  7. PERFORMANCE ANALYSIS OF A RESIDENTIAL GROUND SOURCE HEAT PUMP SYSTEM WITH ANTIFREEZE SOLUTION

    E-Print Network [OSTI]

    PERFORMANCE ANALYSIS OF A RESIDENTIAL GROUND SOURCE HEAT PUMP SYSTEM WITH ANTIFREEZE SOLUTION M in a ground source heat pump system falls near or below 0o C, an antifreeze mixture must be used to prevent freezing in the heat pump. The antifreeze mixture type and concentration has a number of implications

  8. THE EFFECT OF LOCATION OF THE PREDICTED PERFORMANCE OF A HEAT PUMP WATER HEATER

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    #12;THE EFFECT OF LOCATION OF THE PREDICTED PERFORMANCE OF A HEAT PUMP WATER HEATER Laboratory testing and field testing have shown that a heat pump water heater (HPWH) uses about half the electrical energy input that an electric resistance water heater does. However, since the heat pump water heater

  9. The Influence of Heat Transfer Irreversibilities on the Optimal Performance of Diabatic

    E-Print Network [OSTI]

    Salamon, Peter

    The Influence of Heat Transfer Irreversibilities on the Optimal Performance of Diabatic is only slightly dependent on the heat transfer law considered. In the limit of an infinite number of trays even this column with resistance to transfer of heat becomes reversible. 1 #12;Keywords Diabatic

  10. Energy Performance Comparison of Heating and Air Conditioning Systems for Multi-Family Residential Buildings

    SciTech Connect (OSTI)

    Wang, Weimin; Zhang, Jian; Jiang, Wei; Liu, Bing

    2011-07-31

    The type of heating, ventilation and air conditioning (HVAC) system has a large impact on the heating and cooling energy consumption in multifamily residential buildings. This paper compares the energy performance of three HVAC systems: a direct expansion (DX) split system, a split air source heat pump (ASHP) system, and a closed-loop water source heat pump (WSHP) system with a boiler and an evaporative fluid cooler as the central heating and cooling source. All three systems use gas furnace for heating or heating backup. The comparison is made in a number of scenarios including different climate conditions, system operation schemes and applicable building codes. It is found that with the minimum code-compliant equipment efficiency, ASHP performs the best among all scenarios except in extremely code climates. WSHP tends to perform better than the split DX system in cold climates but worse in hot climates.

  11. Heat leak performance of SSC collider dipole magnets

    SciTech Connect (OSTI)

    Weisend, J.G. II; Levin, M.; Franks, D.; Pletzer, R.; Augustynowicz, S.; McInturff, A.D.; Boroski, W.B.

    1993-09-01

    The large number of superconducting dipoles in the SSC results in a stringent heat leak budget for each dipole. Ensuring that the dipoles meet this budget is vital to the successful operation or the collider. This work surveys heat leak measurements taken during 4 different magnet string tests. These tests involved both 40 mm and SO mm aperture dipoles. In these experiments the heat leak to the 80 K shield, 20 K shield and cold mass are measured. The results are compared to predictions from a computational thermal model of the dipole cryostat. Discrepancies are seen between the predicted and measured values. Possible explanations for these discrepancies are given.

  12. Analysis of the performance and space-conditioning impacts of dedicated heat-pump water heaters

    SciTech Connect (OSTI)

    Morrison, L.; Swisher, J.

    1980-12-01

    A description is given of the development and testing of the newly-marketed dedicated heat pump water heater (HPWH), and an analysis is presented of its performance and space conditioning impacts. This system utilizes an air-to-water heat pump, costs about $1000 installed, and obtains a coefficient of performance (COP) of about 2.0 in laboratory and field tests. Since a HPWH is usually installed indoors and extracts heat from the air, its operation is a space conditioning benefit if an air conditioning load exists and a penalty if a space heating load exists. To investigate HPWH performance and a space conditioning impacts, a simulation has been developed to model the thermal performance of a residence with resistance baseboard heat, air conditioning, and either heat pump or resistance water heating. The building characteristics are adapted for three US geographical areas (Madison, Wisconsin; Washington, DC; and Ft. Worth, Texas), and the system is simulated for a year with typical weather data. For each city, HPWH COPs are calculated monthly and yearly. In addition, the water heating and space conditioning energy requirements of HPWH operation are compared with those of resistance water heater operation to determine the relative performance ratio (RPR) of the HPWH. The annual simulated RPRs range from 1.5 to 1.7, which indicate a substantial space heating penalty of HPWH operation in these cities.

  13. High Performance Trays and Heat Exchangers in Heat Pumped Distillation Columns 

    E-Print Network [OSTI]

    Wisz, M. W.; Antonelli, R.; Ragi, E. G.

    1981-01-01

    exchangers and distillation trays permits additional energy savings by lower reboiler temperature differences, and reduced reflux requirements for a fixed column height, due to closer tray spacings. This paper surveys the heat pump systems currently...

  14. Multi-Source Hydronic Heat Pump System Performance Test Bed 

    E-Print Network [OSTI]

    Meckler, M.

    1984-01-01

    of peak power and energy savings allowed by the innovative system. The main difference between the MSHHP and a conventional HVAC system is use of a chilled water "diversity" cooling loop interconnecting air to water coils (located at each water source heat...

  15. Development of ASME performance test code 12.5, single phase heat exchangers

    SciTech Connect (OSTI)

    Lestina, T. [MPR Associates, Alexandria, VA (United States); Scott, B. [Baltimore Gas and Electric Co., Lusby, MD (United States). Calvert Cliffs Nuclear Power Plant

    1998-12-31

    Testing of heat exchanger performance is conducted to (1) confirm that the installed unit meets design specifications, (2) troubleshoot degradation, and (3) assess process improvements. Standard test methods are needed to ensure that highly accurate and reliable test results are obtained. These methods need to predict heat exchanger performance at design conditions based on test measurements at different conditions. ASME Performance Test Code 12.5, Single Phase Heat Exchangers, is under development to meet these needs. This paper summarizes the content of PTC 12.5 which is ready for industry review. The new PTC improves upon existing guidelines because methods to minimize and quantify uncertainty are provided. Overall uncertainty as low as 8% in heat transfer rate and overall heat transfer coefficient is possible for a well designed and properly instrumented thermal performance test.

  16. Performance analysis of reciprocating regenerative magnetic heat pumping. Final report

    SciTech Connect (OSTI)

    Chen, D.T. [Oak Ridge Associated Universities, Inc., TN (United States); Murphy, R.W.; Mei, V.C.; Chen, F.C.; Lue, J.W.; Lubell, M.S. [Oak Ridge National Lab., TN (United States)

    1994-02-01

    Transient flow phenomena in the regenerator tube of reciprocating magnetic heat pumps have been studied numerically and experimentally. In the numerical study, two approaches were taken: (1) solving the energy balance equations for fluid through a porous bed directly and (2) solving the Navier-Stokes equations with a buoyancy force term in the momentum equation. A flow thermal mixing problem was found in both approaches because of the piston-like motion of the regenerator tube that hinders the development of the temperature. The numerical study results show that a 45 K temperature span can be reached in 10 minutes of charge time through the use of a 7-Tesla magnetic field. Using the second numerical approach, temperature stratification in the regenerator fluid column was clearly indicated through temperature rasters. The study also calculates regenerator efficiency and energy delivery rates when heating load and cooling load are applied. Piecewise variation of the regenerator tube moving speed has been used in the present numerical study to control the mass flow rate, reduce thermal mixing of the flow and thus the regenerative losses. The gadolinium`s adiabatic temperature has been measured under 6.5 Tesla of magnet field and different of operating temperatures ranging from 285 K to 320 K. Three regenerative heat pumping tests have also been conducted based on the Reynolds number of the regenerator tube flow, namely Re=300, Re=450, and Re=750 without loads. Maximum temperature span are 12 & 11 K and 9 K for the case of Re=300, Re=450 and Re=750, respectively. Experimental data are in good agreement with the numerical calculation results, and have been used to calibrate the numerical results and to develop a design database for reciprocating-type room-temperature magnetic heat pumps.

  17. Development of a High Performance Air Source Heat Pump for the US Market

    SciTech Connect (OSTI)

    Abdelaziz, Omar [ORNL] [ORNL; Shen, Bo [ORNL] [ORNL; Gao, Zhiming [ORNL] [ORNL; Baxter, Van D [ORNL] [ORNL; Iu, Ipseng [ORNL] [ORNL

    2011-01-01

    Heat pumps present a significant advantage over conventional residential heating technologies due to higher energy efficiencies and less dependence on imported oil. The US development of heat pumps dates back to the 1930 s with pilot units being commercially available in the 1950 s. Reliable and cost competitive units were available in the US market by the 1960 s. The 1973 oil embargo led to increased interest in heat pumps prompting significant research to improve performance, particularly for cold climate locations. Recent increasing concerns on building energy efficiency and environmental emissions have prompted a new wave of research in heat pump technology with special emphasis on reducing performance degradation at colder outdoor air temperatures. A summary of the advantages and limitations of several performance improvement options sought for the development of high performance air source heat pump systems for cold climate applications is the primary focus of this paper. Some recommendations for a high performance cold climate heat pump system design most suitable for the US market are presented.

  18. Effect of Backfill on the Performance of a Vertical U-Tube Ground Coupled Heat Pump 

    E-Print Network [OSTI]

    Gu, Yian

    1995-01-01

    The present work is concerned with developing a discretized analytical model to investigate the effect of a backfill on the performance of a vertical U-tube ground-coupled heat pump. This work involves the development ...

  19. High-Performance Thermoelectric Devices Based on Abundant Silicide Materials for Vehicle Waste Heat Recovery

    Office of Energy Efficiency and Renewable Energy (EERE)

    Development of high-performance thermoelectric devices for vehicle waste heat recovery will include fundamental research to use abundant promising low-cost thermoelectric materials, thermal management and interfaces design, and metrology

  20. Evaluating the performance of passive-solar-heated buildings

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1983-01-01

    Methods of evaluating the thermal performance of passive-solar buildings are reviewed. Instrumentation and data logging requirements are outlined. Various methodologies that have been used to develop an energy balance for the building and various performance measures are discussed. Methods for quantifying comfort are described. Subsystem and other special-purpose monitoring are briefly reviewed. Summary results are given for 38 buildings that have been monitored.

  1. Performance analysis of a latent heat storage system with phase change material for new designed solar collectors in greenhouse heating

    SciTech Connect (OSTI)

    Benli, Hueseyin; Durmus, Aydin

    2009-12-15

    The continuous increase in the level of greenhouse gas emissions and the rise in fuel prices are the main driving forces behind the efforts for more effectively utilize various sources of renewable energy. In many parts of the world, direct solar radiation is considered to be one of the most prospective sources of energy. In this study, the thermal performance of a phase change thermal storage unit is analyzed and discussed. The storage unit is a component of ten pieced solar air collectors heating system being developed for space heating of a greenhouse and charging of PCM. CaCl{sub 2}6H{sub 2}O was used as PCM in thermal energy storage with a melting temperature of 29 C. Hot air delivered by ten pieced solar air collector is passed through the PCM to charge the storage unit. The stored heat is utilized to heat ambient air before being admitted to a greenhouse. This study is based on experimental results of the PCM employed to analyze the transient thermal behavior of the storage unit during the charge and discharge periods. The proposed size of collectors integrated PCM provided about 18-23% of total daily thermal energy requirements of the greenhouse for 3-4 h, in comparison with the conventional heating device. (author)

  2. Performance of an integrated heat pump gas-fired water heater system

    SciTech Connect (OSTI)

    Torab, H.; Sonntag, R.E.

    1984-08-01

    The unsatisfactory performance of the heat pump water heaters (air-to-water) in colder ambient temperatures is the main obstacle to the expansion of the residential market for this device. On the other hand, the price increase of natural gas in the 1980's encourages retrofitting or replacing the existing gas-fired water heaters. The present study examines the possibility of retrofitting the gas-fired water heater with a heat pump water heater. The result of the investigation on the thermodynamic and economic performance of a water heater system comprised of a heat pump water heater and a gas-fired water heater is presented in this paper.

  3. Multiwalled carbon nanotube/polydimethylsiloxane composite films as high performance flexible electric heating elements

    SciTech Connect (OSTI)

    Yan, Jing; Jeong, Young Gyu, E-mail: ygjeong@cnu.ac.kr [Department of Advanced Organic Materials and Textile System Engineering, Chungnam National University, Daejeon 305-764 (Korea, Republic of)

    2014-08-04

    High performance elastomeric electric heating elements were prepared by incorporating various contents of pristine multiwalled carbon nanotube (MWCNT) in polydimethylsiloxane (PDMS) matrix by using an efficient solution-casting and curing technique. The pristine MWCNTs were identified to be uniformly dispersed in the PDMS matrix and the electrical percolation of MWCNTs was evaluated to be at ?0.27?wt.?%, where the electrical resistivity of the MWCNT/PDMS composite films dropped remarkably. Accordingly, the composite films with higher MWCNT contents above 0.3?wt.?% exhibit excellent electric heating performance in terms of temperature response rapidity and electric energy efficiency at constant applied voltages. In addition, the composite films, which were thermally stable up to 250?°C, showed excellent heating-cooling cyclic performance, which was associated with operational stability in actual electric heating applications.

  4. The Efficacy of SEER as a Seasonal Performance Measure for Different Climates 

    E-Print Network [OSTI]

    Henderson, H. I.; Sachs, H. M.

    2006-01-01

    equipment model is the DXDOE model from the ASHRAE secondary toolkit (Brandemuehl et al 1993). A similar coil model is used in EnergyPlus (Energy Plus 2001). The DXDOE component model is based on a semi- empirical performance map that uses a bypass... and Subroutines for Secondary HVAC Systems Energy Calculations. ASHRAE, Atlanta. EnergyPlus. 2001. EnergyPlus engineering document: The reference to energy plus calculations, April, www.energyplus.gov. Federal Register. 1979. Test procedures for central...

  5. PERFORMANCE EVALUATION OF AN AIR-TO-AIR HEAT PUMP COUPLED WITH TEMPERATE AIR-SOURCES INTEGRATED INTO A DWELLING

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    PERFORMANCE EVALUATION OF AN AIR-TO-AIR HEAT PUMP COUPLED WITH TEMPERATE AIR-SOURCES INTEGRATED.peuportier@mines-paristech.fr, Tel.: +33 1 40 51 91 51 ABSTRACT An inverter-driven air-to-air heat pump model has been developped capacity air-to-air heat pump coupled with temperate air sources (crawlspace, attic, sunspace, heat

  6. Cooling and Heating Season Impacts of Right-Sizing of Fixed- and Variable-Capacity Heat Pumps With Attic and Indoor Ductwork

    SciTech Connect (OSTI)

    Cummings, James; Withers, Charles; Kono, Jamie

    2015-06-24

    A new generation of full variable-capacity air-conditioning (A/C) and heat pump units has come on the market that promises to deliver very high cooling and heating efficiency. The units are controlled differently than standard single-capacity (fixed-capacity) systems. Instead of cycling on at full capacity and cycling off when the thermostat is satisfied, the new units can vary their capacity over a wide range (approximately 40%–118% of nominal full capacity) and stay on for 60%–100% more hours per day than the fixed-capacity systems depending on load-to-capacity ratios. Two-stage systems were not evaluated in this research effort.

  7. Design and performance of a new induction furnace for heat treatment of superconducting radiofrequency niobium cavities

    SciTech Connect (OSTI)

    Dhakal, Pashupati; Ciovati, Gianluigi; Myneni, Ganapati Rao [Jefferson Lab, Newport News, Virginia 23606 (United States); Rigby, Wayne [Specialty Vacuum, Placitas, New Mexico 87043 (United States); Wallace, John [Casting Analysis Corporation, Weyers Cave, Virginia 24468 (United States)

    2012-06-15

    Superconducting radio frequency (SRF) cavities made of high purity niobium (Nb) are the building blocks of many modern particle accelerators. The fabrication process includes several cycles of chemical and heat treatment at low ({approx}120 Degree-Sign C) and high ({approx}800 Degree-Sign C) temperatures. In this contribution, we describe the design and performance of an ultra-high-vacuum furnace which uses an induction heating system to heat treat SRF cavities. Cavities are heated by radiation from the Nb susceptor. By using an all-niobium hot zone, contamination of the Nb cavity by foreign elements during heat treatment is minimized and allows avoiding subsequent chemical etching. The furnace was operated up to 1400 Degree-Sign C with a maximum pressure of {approx}1 Multiplication-Sign 10{sup -5} Torr and the maximum achievable temperature is estimated to be higher than 2000 Degree-Sign C. Initial results on the performance of a single cell 1.5 GHz cavity made of ingot Nb heat treated at 1200 Degree-Sign C using this new induction furnace and without subsequent chemical etching showed a reduction of the RF losses by a factor of {approx}2 compared to cavities made of fine-grain Nb which underwent standard chemical and heat treatments.

  8. Design and performance of a new induction furnace for heat treatment of superconducting radiofrequency niobium cavities

    SciTech Connect (OSTI)

    Pashupati Dhakal, Gianluigi Ciovati, Wayne Rigby, John Wallace, Ganapati Rao Myneni

    2012-06-01

    Superconducting radio frequency (SRF) cavities made of high purity niobium (Nb) are the building blocks of many modern particle accelerators. The fabrication process includes several cycles of chemical and heat treatment at low ({approx}120 deg C) and high ({approx}800 deg C) temperatures. In this contribution, we describe the design and performance of an ultra-high-vacuum furnace which uses an induction heating system to heat treat SRF cavities. Cavities are heated by radiation from the Nb susceptor. By using an all-niobium hot zone, contamination of the Nb cavity by foreign elements during heat treatment is minimized and allows avoiding subsequent chemical etching. The furnace was operated up to 1400 deg C with a maximum pressure of {approx}1 x 10{sup -5} Torr and the maximum achievable temperature is estimated to be higher than 2000 deg C. Initial results on the performance of a single cell 1.5 GHz cavity made of ingot Nb heat treated at 1200 deg C using this new induction furnace and without subsequent chemical etching showed a reduction of the RF losses by a factor of {approx}2 compared to cavities made of fine-grain Nb which underwent standard chemical and heat treatments.

  9. Foundation Heat Exchanger Final Report: Demonstration, Measured Performance, and Validated Model and Design Tool

    SciTech Connect (OSTI)

    Hughes, Patrick [ORNL; Im, Piljae [ORNL

    2012-01-01

    Geothermal heat pumps, sometimes called ground-source heat pumps (GSHPs), have been proven capable of significantly reducing energy use and peak demand in buildings. Conventional equipment for controlling the temperature and humidity of a building, or supplying hot water and fresh outdoor air, must exchange energy (or heat) with the building's outdoor environment. Equipment using the ground as a heat source and heat sink consumes less non-renewable energy (electricity and fossil fuels) because the earth is cooler than outdoor air in summer and warmer in winter. The most important barrier to rapid growth of the GSHP industry is high first cost of GSHP systems to consumers. The most common GSHP system utilizes a closed-loop ground heat exchanger. This type of GSHP system can be used almost anywhere. There is reason to believe that reducing the cost of closed-loop systems is the strategy that would achieve the greatest energy savings with GSHP technology. The cost premium of closed-loop GSHP systems over conventional space conditioning and water heating systems is primarily associated with drilling boreholes or excavating trenches, installing vertical or horizontal ground heat exchangers, and backfilling the excavations. This project investigates reducing the cost of horizontal closed-loop ground heat exchangers by installing them in the construction excavations, augmented when necessary with additional trenches. This approach applies only to new construction of residential and light commercial buildings or additions to such buildings. In the business-as-usual scenario, construction excavations are not used for the horizontal ground heat exchanger (HGHX); instead the HGHX is installed entirely in trenches dug specifically for that purpose. The potential cost savings comes from using the construction excavations for the installation of ground heat exchangers, thereby minimizing the need and expense of digging additional trenches. The term foundation heat exchanger (FHX) has been coined to refer exclusively to ground heat exchangers installed in the overcut around the basement walls. The primary technical challenge undertaken by this project was the development and validation of energy performance models and design tools for FHX. In terms of performance modeling and design, ground heat exchangers in other construction excavations (e.g., utility trenches) are no different from conventional HGHX, and models and design tools for HGHX already exist. This project successfully developed and validated energy performance models and design tools so that FHX or hybrid FHX/HGHX systems can be engineered with confidence, enabling this technology to be applied in residential and light commercial buildings. The validated energy performance model also addresses and solves another problem, the longstanding inadequacy in the way ground-building thermal interaction is represented in building energy models, whether or not there is a ground heat exchanger nearby. Two side-by-side, three-level, unoccupied research houses with walkout basements, identical 3,700 ft{sup 2} floor plans, and hybrid FHX/HGHX systems were constructed to provide validation data sets for the energy performance model and design tool. The envelopes of both houses are very energy efficient and airtight, and the HERS ratings of the homes are 44 and 45 respectively. Both houses are mechanically ventilated with energy recovery ventilators, with space conditioning provided by water-to-air heat pumps with 2 ton nominal capacities. Separate water-to-water heat pumps with 1.5 ton nominal capacities were used for water heating. In these unoccupied research houses, human impact on energy use (hot water draw, etc.) is simulated to match the national average. At House 1 the hybrid FHX/HGHX system was installed in 300 linear feet of excavation, and 60% of that was construction excavation (needed to construct the home). At House 2 the hybrid FHX/HGHX system was installed in 360 feet of excavation, 50% of which was construction excavation. There are six pipes in all excavations (three par

  10. BWR spent fuel storage cask performance test. Volume 1. Cask handling experience and decay heat, heat transfer, and shielding data

    SciTech Connect (OSTI)

    McKinnon, M.A.; Doman, J.W.; Tanner, J.E.; Guenther, R.J.; Creer, J.M.; King, C.E.

    1986-02-01

    This report documents a heat transfer and shielding performance test conducted on a Ridihalgh, Eggers and Associates REA 2023 boiling water reactor (BWR) spent fuel storage cask. The testing effort consisted of three parts: pretest preparations, performance testing, and post-test activities. Pretest preparations included conducting cask handling dry runs and characterizing BWR spent fuel assemblies from Nebraska Public Power District's Cooper Nuclear Station. The performance test matrix included 14 runs consisting of two loadings, two cask orientations, and three backfill environments. Post-test activities included calorimetry and axial radiation scans of selected fuel assemblies, in-basin sipping of each assembly, crud collection, video and photographic scans, and decontamination of the cask interior and exterior.

  11. IEA Heat Pump Conference 2011, 16 -19 May 2011, Tokyo, Japan ON SIDE REFRIGERANT MEASUREMENT OF HEAT PUMP

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    - 1 - 10th IEA Heat Pump Conference 2011, 16 - 19 May 2011, Tokyo, Japan ON SIDE REFRIGERANT MEASUREMENT OF HEAT PUMP SEASONAL PERFORMANCES C. T. Tran, PhD student, Centre for Energy and Processes, MINES, Research Engineer, ENERBAT, Electricity of France R&D, Moret/Loing, France Abstract Heat pump systems have

  12. PERFORMANCE OF RESIDENTIAL AIR-TO-AIR HEAT EXCHANGERS: TEST METHODS AND RESULTS

    E-Print Network [OSTI]

    Fisk, William J.

    2013-01-01

    effectiveness of a heat exchanger rates due to the decreasesthrough volumetric flow the rate heat of exchanger. the twothe heat exchanger. The rate of heat transfer "Q" between

  13. Improving the Control Performance of an Organic Rankine Cycle System for Waste Heat Recovery from a Heavy-Duty

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Improving the Control Performance of an Organic Rankine Cycle System for Waste Heat Recovery from waste heat from a heavy- duty diesel engine. For this system, a hierarchical and modular control) for recovering waste heat from a heavy-duty diesel engine. For this system, a hierarchical and modular control

  14. Field Study of Performance, Comfort, and Sizing of Two Variable-Speed Heat Pumps Installed in a Single 2-Story Residence

    SciTech Connect (OSTI)

    Munk, Jeffrey D [ORNL; Odukomaiya, Adewale O [ORNL; Gehl, Anthony C [ORNL; Jackson, Roderick K [ORNL

    2014-01-01

    With the recent advancements in the application of variable-speed (VS) compressors to residential HVAC systems, opportunities are now available to size heat pumps (HPs) to more effectively meet heating and cooling loads in many of the climate zones in the US with limited use of inefficient resistance heat. This is in contrast to sizing guidance for traditional single-speed HPs that limits the ability to oversize with regard to cooling loads, because of risks of poor dehumidification during the cooling season and increased cycling losses. VS-drive HPs can often run at 30-40% of their rated cooling capacity to reduce cycling losses, and can adjust fan speed to provide better indoor humidity control. Detailed air-side performance data was collected on two VS-drive heat pumps installed in a single unoccupied research house in Knoxville, TN, a mixed-humid climate. One system provided space conditioning for the upstairs, while the other unit provided space conditioning for the downstairs. Occupancy was simulated by operating the lights, shower, appliances, other plug loads, etc. to simulate the sensible and latent loads imposed on the building space by internal electric loads and human occupants according to the Building America Research Benchmark (2008). The seasonal efficiency and energy use of the units are calculated. Annual energy use is compared to that of the single speed minimum efficiency HPs tested in the same house previously. Sizing of the units relative to the measured building load and manual J design load calculations is examined. The impact of the unit sizing with regards to indoor comfort is also evaluated.

  15. PERFORMANCE IMPROVEMENTS IN COMMERCIAL HEAT PUMP WATER HEATERS USING CARBON DIOXIDE

    SciTech Connect (OSTI)

    BOWERS C.D.; ELBEL S.; PETERSEN M.; HRNJAK P.S.

    2011-07-01

    Although heat pump water heaters are today widely accepted in Japan, where energy costs are high and government incentives for their use exist, acceptance of such a product in the U.S. has been slow. This trend is slowly changing with the introduction of heat pump water heaters into the residential market, but remains in the commercial sector. Barriers to heat pump water heater acceptance in the commercial market have historically been performance, reliability and first/operating costs. The use of carbon dioxide (R744) as the refrigerant in such a system can improve performance for relatively small increase in initial cost and make this technology more appealing. What makes R744 an excellent candidate for use in heat pump water heaters is not only the wide range of ambient temperatures within which it can operate, but also the excellent ability to match water to refrigerant temperatures on the high side, resulting in very high exit water temperatures of up to 82�ºC (180�ºF), as required by sanitary codes in the U.S.(Food Code, 2005), in a single pass, temperatures that are much more difficult to reach with other refrigerants. This can be especially attractive in applications where this water is used for the purpose of sanitation. While reliability has also been of concern historically, dramatic improvements have been made over the last several years through research done in the automotive industry and commercialization of R744 technology in residential water heating mainly in Japan. This paper presents the performance results from the development of an R744 commercial heat pump water heater of approximately 35kW and a comparison to a baseline R134a unit of the same capacity and footprint. In addition, recommendations are made for further improvements of the R744 system which could result in possible energy savings of up to 20%.

  16. Statistical comparison of ICRF and NBI heating performance in JET-ILW L-mode plasmas

    SciTech Connect (OSTI)

    Lerche, E.; Van Eester, D.; Jacquet, Ph.; Mayoral, M.-L.; Graham, M.; Matthews, G.; Monakhov, I.; Rimini, F.; Colas, L.; Czarnecka, A.; Vries, P. de; Collaboration: JET-EFDA Contributors

    2014-02-12

    After the change over from the C-wall to the ITER-like Be/W wall (ILW) in JET, the radiation losses during ICRF heating have increased and are now substantially larger than those observed with NBI at the same power levels, in spite of the similar global plasma energies reached with the two heating systems. A comparison of the NBI and ICRF performances in the JET-ILW experiments, based on a statistical analysis of ?3000 L-mode discharges, will be presented.

  17. NREL Tests Integrated Heat Pump Water Heater Performance in Different Climates (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-01-01

    This technical highlight describes NREL tests to capture information about heat pump performance across a wide range of ambient conditions for five heat pump water heaters (HPWH). These water heaters have the potential to significantly reduce water heater energy use relative to traditional electric resistance water heaters. These tests have provided detailed performance data for these appliances, which have been used to evaluate the cost of saved energy as a function of climate. The performance of HPWHs is dependent on ambient air temperature and humidity and the logic controlling the heat pump and the backup resistance heaters. The laboratory tests were designed to measure each unit's performance across a range of air conditions and determine the specific logic controlling the two heat sources, which has a large effect on the comfort of the users and the energy efficiency of the system. Unlike other types of water heaters, HPWHs are both influenced by and have an effect on their surroundings. Since these effects are complex and different for virtually every house and climate region, creating an accurate HPWH model from the data gathered during the laboratory tests was a main goal of the project. Using the results from NREL's laboratory tests, such as the Coefficient of Performance (COP) curves for different air conditions as shown in Figure 1, an existing HPWH model is being modified to produce more accurate whole-house simulations. This will allow the interactions between the HPWH and the home's heating and cooling system to be evaluated in detail, for any climate region. Once these modeling capabilities are in place, a realistic cost-benefit analysis can be performed for a HPWH installation anywhere in the country. An accurate HPWH model will help to quantify the savings associated with installing a HPWH in the place of a standard electric water heater. In most locations, HPWHs are not yet a cost-effective alternative to natural gas water heaters. The detailed system performance maps that were developed by this testing program will be used to: (1) Target regions of the country that would benefit most from this technology; (2) Identify improvements in current systems to maximize homeowner cost savings; and (3) Explore opportunities for development of advanced hot water heating systems.

  18. Field Performance of Heat Pump Water Heaters in the Northeast, Massachusetts and Rhode Island (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2013-12-01

    Heat pump water heaters (HPWHs) are finally entering the mainstream residential water heater market. Potential catalysts are increased consumer demand for higher energy efficiency electric water heating and a new Federal water heating standard that effectively mandates use of HPWHs for electric storage water heaters with nominal capacities greater than 55 gallons. When compared to electric resistance water heating, the energy and cost savings potential of HPWHs is tremendous. Converting all electric resistance water heaters to HPWHs could save American consumers 7.8 billion dollars annually ($182 per household) in water heating operating costs and cut annual residential source energy consumption for water heating by 0.70 quads. Steven Winter Associates, Inc. embarked on one of the first in situ studies of these newly released HPWH products through a partnership with two sponsoring electric utility companies, National Grid and NSTAR, and one sponsoring energy efficiency service program administrator, Cape Light Compact. Recent laboratory studies have measured performance of HPWHs under various operating conditions, but publicly available field studies have not been as available. This evaluation attempts to provide publicly available field data on new HPWHs by monitoring the performance of three recently released products (General Electric GeoSpring, A.O. Smith Voltex, and Stiebel Eltron Accelera 300). Fourteen HPWHs were installed in Massachusetts and Rhode Island and monitored for over a year. Of the 14 units, ten were General Electric models (50 gallon units), two were Stiebel Eltron models (80 gallon units), and two were A.O. Smith models (one 60-gallon and one 80-gallon unit).

  19. Field Performance of Inverter-Driven Heat Pumps in Cold Climates

    SciTech Connect (OSTI)

    Williamson, James; Aldrich, Robb

    2015-08-19

    Traditionally, air-source heat pumps (ASHPs) have been used more often in warmer climates; however, some new ASHPs are gaining ground in colder areas. These systems operate at subzero (Fahrenheit) temperatures and many do not include backup electric resistance elements. There are still uncertainties, however, about capacity and efficiency in cold weather. Also, questions such as “how cold is too cold?” do not have clear answers. These uncertainties could lead to skepticism among homeowners; poor energy savings estimates; suboptimal system selection by heating, ventilating, and air-conditioning contractors; and inconsistent energy modeling. In an effort to better understand and characterize the heating performance of these units in cold climates, the U.S. Department of Energy Building America team, Consortium for Advanced Residential Buildings (CARB), monitored seven inverter-driven, ductless ASHPs across the Northeast. Operating data were collected for three Mitsubishi FE18 units, three Mitsubishi FE12 units, and one Fujitsu 15RLS2 unit. The intent of this research was to assess heat output, electricity consumption, and coefficients of performance (COPs) at various temperatures and load conditions. This assessment was accomplished with long- and short-term tests that measured power consumption; supply, return, and outdoor air temperatures; and airflow through the indoor fan coil.

  20. Heat Transfer Performance of a Dry and Wet / Dry Advanced Cooling Tower Condenser 

    E-Print Network [OSTI]

    Fricke, H. D.; Webster, D. J.; McIlroy, K.; Bartz, J. A.

    1981-01-01

    PERFORMANCE OF A DRY AND WET/DRY ADVANCED COOLING TOWER CONDENSER Hans D. Fricke, David J. Webster, Kenneth McIlroy Union carbide Corporation - Linde Division, Tonawanda, New York John A. Bartz Electric Power Research Institute, Palo Alto, california... cooling in creases siting flexibility, particularly for locations in arid Western coal fields. However, dry cooling requires considerable capital investment for the cooling towers. Hence, the development of effitient (low cost) heat transfer surfaces...

  1. Heat Pipe Performance Enhancement with Binary Mixture Fluids that Exhibit Strong Concentration Marangoni Effects

    E-Print Network [OSTI]

    Armijo, Kenneth Miguel

    2011-01-01

    Pipes for Waste Heat Recovery…..………………………………… Chapter 2 –analysis involving waste heat recovery of solar energyof Industrial Waste Heat Recovery Technologies for Moderate

  2. Study on Performance Verification and Evaluation of District Heating and Cooling System Using Thermal Energy of River Water 

    E-Print Network [OSTI]

    Takahashi,N.; Niwa, H.; Kawano,M.; Koike,K.; Koga,O.; Ichitani, K.; Mishima,N.

    2014-01-01

    SEKKEI Research Institute Naoki Takahashi Study on Performance Verification and Evaluation of District Heating and Cooling System Using Thermal Energy of River Water ESL-IC-14-09-19 Proceedings of the 14th International Conference for Enhanced Building... Operations, Beijing, China, September 14-17, 2014 1The heating and cooling system used in Osaka’s Nakanoshima district uses heat pumps and river water to achieve the efficient use of the heat source and mitigate the heat island effect. The system...

  3. PERFORMANCE OF RESIDENTIAL AIR-TO-AIR HEAT EXCHANGERS: TEST METHODS AND RESULTS

    E-Print Network [OSTI]

    Fisk, William J.

    2013-01-01

    another. Another type of heat exchanger is a heat wheel (ferent for each type of heat exchanger. exchanger may heatopposite directions. A heat similar type of exchanger 1s the

  4. Performance analysis of dedicated heat-pump water heaters in an office building

    SciTech Connect (OSTI)

    Morrison, L.

    1981-05-01

    An evaluation is made of the performance of two generic dedicated heat pump water heaters (HPWHs) in supplying the domestic hot water (DHW) needs of a medium-sized office building in Colorado. Results are based on preliminary data measurements, and assumptions are made to compensate for a faulty flow meter. A stand-alone heat pump plumbed to a conventional tank obtains a coefficient of performance (COP) of 2.4 but only delivers load water temperatures of about 41/sup 0/C (105/sup 0/F) because of the 15,142 L/day (4000 gal/day) recirculating loop flow. An industrial-grade stand-alone HPWH will replace this unit. An integral heat pump/tank unit is being tested, but results are not available because of compressor starting problems. Recirculating loop losses account for 75% of the energy delivered by the HPWHs. These losses could be reduced by 75% if the recirculating loop were insulated, thus reducing the DHW fuel costs by 50%. The insulation expense could be paid in less than 3 years by savings in DHW fuel costs.

  5. Device and method for measuring the coefficient of performance of a heat pump

    DOE Patents [OSTI]

    Brantley, V.R.; Miller, D.R.

    1982-05-18

    A method and instrument is provided which allows quick and accurate measurement of the coefficient of performance of an installed electrically powered heat pump including auxiliary resistane heaters. Temperature-sensitive resistors are placed in the return and supply air ducts to measure the temperature increase of the air across the refrigerant and resistive-heating elements of the system. The voltages across the resistors which are directly proportional to the respective duct tempertures are applied to the inputs of a differential amplifier so that its output voltage is proportional to the temperature difference across the unit. A voltage-to-frequency converter connected to the output of the differential amplifier converts the voltage signal to a proportional-frequency signal. A digital watt meter is used to measure the power to the unit and produces a signal having a frequency proportional to the input power. A digital logic circuit ratios the temperature difference signal and the electric power input signal in a unique manner to produce a single number which is the coefficient of performance of the unit over the test interval. The digital logic and an in-situ calibration procedure enables the instrument to make these measurements in such a way that the ratio of heat flow/power input is obtained without computations. No specialized knowledge of thermodynamics or electrons is required to operate the instrument.

  6. Device and method for measuring the coefficient of performance of a heat pump

    DOE Patents [OSTI]

    Brantley, Vanston R. (Knoxville, TN); Miller, Donald R. (Kingston, TN)

    1984-01-01

    A method and instrument is provided which allows quick and accurate measurement of the coefficient of performance of an installed electrically powered heat pump including auxiliary resistance heaters. Temperature sensitive resistors are placed in the return and supply air ducts to measure the temperature increase of the air across the refrigerant and resistive heating elements of the system. The voltages across the resistors which are directly proportional to the respective duct temperatures are applied to the inputs of a differential amplifier so that its output voltage is proportional to the temperature difference across the unit. A voltage-to-frequency converter connected to the output of the differential amplifier converts the voltage signal to a proportional frequency signal. A digital watt meter is used to measure the power to the unit and produces a signal having a frequency proportional to the input power. A digital logic circuit ratios the temperature difference signal and the electric power input signal in a unique manner to produce a single number which is the coefficient of performance of the unit over the test interval. The digital logic and an in-situ calibration procedure enables the instrument to make these measurements in such a way that the ratio of heat flow/power input is obtained without computations. No specialized knowledge of thermodynamics or electronics is required to operate the instrument.

  7. A Tool for Life Cycle Climate Performance (LCCP) Based Design of Residential Air Source Heat Pumps

    SciTech Connect (OSTI)

    Beshr, Mohamed [University of Maryland, College Park; Aute, Vikrant [University of Maryland, College Park; Abdelaziz, Omar [ORNL; Fricke, Brian A [ORNL; Radermacher, Reinhard [University of Maryland, College Park

    2014-01-01

    A tool for the design of air source heat pumps (ASHP) based on their life cycle climate performance (LCCP) analysis is presented. The LCCP model includes direct and indirect emissions of the ASHP. The annual energy consumption of the ASHP is determined based on AHRI Standard 210/240. The tool can be used as an evaluation tool when the user inputs the required performance data based on the ASHP type selected. In addition, this tool has system design capability where the user inputs the design parameters of the different components of the heat pump and the tool runs the system simulation software to calculate the performance data. Additional features available in the tool include the capability to perform parametric analysis and sensitivity study on the system. The tool has 14 refrigerants, and 47 cities built-in with the option for the user to add more refrigerants, based on NIST REFPROP, and cities, using TMY-3 database. The underlying LCCP calculation framework is open source and can be easily customized for various applications. The tool can be used with any system simulation software, load calculation tool, and weather and emissions data type.

  8. Design Approach and Performance Analysis of a Small Integrated Heat Pump (IHP) for Net Zero Energy Homes (ZEH)

    SciTech Connect (OSTI)

    Rice, C Keith [ORNL; Murphy, Richard W [ORNL; Baxter, Van D [ORNL

    2008-01-01

    This paper describes the design and performance analysis of a variable-capacity heat pump system developed for a small [1800ft2 (167 m2)] prototype net ZEH with an average design cooling load of 1.25 tons (4.4 kW) in five selected US climates. The heat pump integrates space heating and cooling, water heating, ventilation, and humidity control (humidification and dehumidification) functions into a single integrated heat pump (IHP) unit. The design approach uses one small variable-capacity compressor to meet all the above functions in an energy efficient manner. Modal performance comparisons to an earlier IHP product are shown relative to the proposed new design for net ZEH application. The annual performance analysis approach using TRNSYS in conjunction with the ORNL Heat Pump Design Model is discussed. Annual performance projections for a range of locations are compared to those of a base system consisting of separate pieces of equipment to perform the same functions. The ZEH IHP is projected to reduce energy use for space heating & cooling, water heating, dehumidification, and ventilation for a net ZEH by about 50% compared to that of the base system.

  9. Methodology for Calculating Cooling and Heating Energy-Imput-Ratio (EIR) From the Rated Seasonal Performance Efficiency (SEER or HSPF) 

    E-Print Network [OSTI]

    Kim, H.; Baltazar, J. C.; Haberl, J. S.

    2013-01-01

    studies. In this analysis, only the units of which SEER are higher than or equal to SEER 13 were considered. For the FSEC model, the AHRI default fan power (0.365 Watt per CFM) was added with an assumed airflow of 400 CFM/ton, since the FSEC model.... In this analysis, only the units of which HSPF are higher than or equal to HSPF 7.7 were considered. For the FSEC model, the AHRI default fan power (0.365 Watt per CFM) was added with an assumed airflow of 400 CFM/ton, since the FSEC model directly converts...

  10. Divertor Heat Flux Mitigation in High-Performance H-mode Plasmas in the National Spherical Torus

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    magnetic flux expansion and partial detachment of the outer strike point at several D2 injection rates of acceptable divertor plate material erosion rates and heat fluxes to q 10 MW/m2 , a limit imposedDivertor Heat Flux Mitigation in High-Performance H-mode Plasmas in the National Spherical Torus

  11. Monitored performance of residential geothermal heat pumps in central Texas and Southern Michigan

    SciTech Connect (OSTI)

    Sullivan, W.N.

    1997-11-01

    This report summarizes measured performance of residential geothermal heat pumps (GHP`s) that were installed in family housing units at Ft. Hood, Texas and at Selfridge Air National Guard base in Michigan. These units were built as part of a joint Department of Defense/Department of Energy program to evaluate the energy savings potential of GHP`s installed at military facilities. At the Ft. Hood site, the GHP performance was compared to conventional forced air electric air conditioning and natural gas heating. At Selfridge, the homes under test were originally equipped with electric baseboard heat and no air conditioning. Installation of the GHP systems at both sites was straightforward but more problems and costs were incurred at Selfridge because of the need to install ductwork in the homes. The GHP`s at both sites produced impressive energy savings. These savings approached 40% for most of the homes tested. The low cost of energy on these bases relative to the incremental cost of the GHP conversions precludes rapid payback of the GHP`s from energy savings alone. Estimates based on simple payback (no inflation and no interest on capital) indicated payback times from 15 to 20 years at both sites. These payback times may be reduced by considering the additional savings possible due to reduced maintenance costs. Results are summarized in terms of 15 minute, hourly, monthly, and annual performance parameters. The results indicate that all the systems were working properly but several design shortcomings were identified. Recommendations are made for improvements in future installations at both sites.

  12. An Exploratory Study of the New Performance Index of the Heat Pump System Based on the Second Law of Thermodynamics 

    E-Print Network [OSTI]

    Xu, W.; Li, H.

    2006-01-01

    The coefficient of performance (COP) of the heat pump system, based on the first law of thermodynamics and reflecting the quantity relation of input and output energy, has certain limitations on the evaluation of energy-saving efficiency...

  13. Assessment and Prediction of the Thermal Performance of a Centralized Latent Heat Thermal Energy Storage Utilizing Artificial Neural Network 

    E-Print Network [OSTI]

    El-Sawi, A.; Haghighat, F.; Akbari, H.

    2013-01-01

    A simulation tool is developed to analyze the thermal performance of a centralized latent heat thermal energy storage system (LHTES) using computational fluid dynamics (CFD). The LHTES system is integrated with a mechanical ventilation system...

  14. Measured Space Conditioning and Water Heating Performance of a Ground-Source Integrated Heat Pump in a Residential Application

    SciTech Connect (OSTI)

    Munk, Jeffrey D [ORNL] [ORNL; Ally, Moonis Raza [ORNL] [ORNL; Baxter, Van D [ORNL] [ORNL; Gehl, Anthony C [ORNL] [ORNL

    2014-01-01

    In an effort to reduce residential building energy consumption, a ground-source integrated heat pump was developed to meet a home s entire space conditioning and water heating needs, while providing 50% energy savings relative to a baseline suite of minimum efficiency equipment. A prototype 7.0 kW system was installed in a 344 m2 research house with simulated occupancy in Oak Ridge, TN. The equipment was monitored from June 2012 through January 2013.

  15. The effects of airflow modulation and multi-stage defrost on the performance of an air source heat pump 

    E-Print Network [OSTI]

    Payne, William Vance

    1992-01-01

    Modeling System Performance Cycling Losses Frosting and Defrosting Losses . Heat Pump Defrost Controls. Effects of Frost on Airflow Summary of Literature Reviewed . 7 12 16 26 34 41 TEST FACILITY. Psychrometric Rooms Test Heat Pump . . Indoor... Test Section. . Outdoor Test Section. Data Acquisition and Reduction. Experimental Procedure. 44 46 49 51 52 53 IV BASE CASE TEST RESULTS . System Performance Parameters. Frosting Period . Defrost Initiation. Melt Period . . Drain Period...

  16. Heat Pipe Performance Enhancement with Binary Mixture Fluids that Exhibit Strong Concentration Marangoni Effects

    E-Print Network [OSTI]

    Armijo, Kenneth Miguel

    2011-01-01

    16] Faghri, A. , 1995, “Heat pipe science and technology,”Chisholm, D. , 1971, The Heat Pipe, Mills & Boon Limited,thermosyphon,” Proc. 5th Int. Heat Pipe Conf. , pp. 11–17. [

  17. Thermal Performance of Microencapsulated Phase Material (MPCM) Slurry in a Coaxial Heat Exchanger 

    E-Print Network [OSTI]

    Yu, Kun

    2014-05-08

    Microencapsulated phase change material (MPCM) slurries and coil heat exchangers had been recently studied separately as enhancers of convective heat transfer processes. Due to the larger apparent heat related to the phase change process...

  18. West Village Community: Quality Management Processes and Preliminary Heat Pump Water Heater Performance

    SciTech Connect (OSTI)

    Dakin, B.; Backman, C.; Hoeschele, M.; German, A.

    2012-11-01

    West Village, a multi-use project underway at the University of California Davis, represents a ground-breaking sustainable community incorporating energy efficiency measures and on-site renewable generation to achieve community-level Zero Net Energy (ZNE) goals. The project when complete will provide housing for students, faculty, and staff with a vision to minimize the community's impact on energy use by reducing building energy use, providing on-site generation, and encouraging alternative forms of transportation. This focus of this research is on the 192 student apartments that were completed in 2011 under Phase I of the West Village multi-year project. The numerous aggressive energy efficiency measures implemented result in estimated source energy savings of 37% over the B10 Benchmark. There are two primary objectives of this research. The first is to evaluate performance and efficiency of the central heat pump water heaters as a strategy to provide efficient electric water heating for net-zero all-electric buildings and where natural gas is not available on site. In addition, effectiveness of the quality assurance and quality control processes implemented to ensure proper system commissioning and to meet program participation requirements is evaluated. Recommendations for improvements that could improve successful implementation for large-scale, high performance communities are identified.

  19. Instrumented performance study of a passive solar heated earth sheltered residence

    SciTech Connect (OSTI)

    Yarnell, R.C.; Yarnell, B.K.

    1983-01-01

    This paper reports the results of a one year effort to gather performance data on an earth sheltered, passive solar house located in Carson City, Nevada. Automatic equipment logged insolation and temperature data for a one (1) year period commencing shortly after completion of construction of the structure and its occupancy by the owners. The use of a recording micrologger reflects an effort to obtain unbiased, factual data on the performance of the house and to reduce the impact of subjective perceptions of the occupants' comfort on the report. Raw data was gathered continuously. A pyranometer measured the amount of whole sky solar radiation. Results were recorded as Btu's per square foot. Thermistors measured temperatures of: (a) outdoor ambient air, (b) indoor living room ambient air, (c) indoor greenhouse ambient air, (d) dining room mass wall, (e) greenhouse mass wall, (f) perimeter earth-sheltered wall, and (g) solar heated DHW storage tank. An event counter recorded user operated insulating adjustments (raising and lowering of insulating of curtains) and auxiliary heating (building or stoking a fire in the wood burning stove).

  20. West Village Community. Quality Management Processes and Preliminary Heat Pump Water Heater Performance

    SciTech Connect (OSTI)

    Dakin, B.; Backman, C.; Hoeschele, M.; German, A.

    2012-11-01

    West Village, a multi-use project underway at the University of California Davis, represents a ground-breaking sustainable community incorporating energy efficiency measures and on-site renewable generation to achieve community-level Zero Net Energy (ZNE) goals. When complete, the project will provide housing for students, faculty, and staff with a vision to minimize the community’s impact on energy use by reducing building energy use, providing on-site generation, and encouraging alternative forms of transportation. This focus of this research is on the 192 student apartments that were completed in 2011 under Phase I of the West Village multi-year project. The numerous aggressive energy efficiency measures implemented result in estimated source energy savings of 37% over the B10 Benchmark. There are two primary objectives of this research. The first is to evaluate performance and efficiency of the central heat pump water heaters as a strategy to provide efficient electric water heating for net-zero all-electric buildings and where natural gas is not available on site. In addition, effectiveness of the quality assurance and quality control processes implemented to ensure proper system commissioning and to meet program participation requirements is evaluated. Recommendations for improvements that could improve successful implementation for large-scale, high performance communities are identified.

  1. PERFORMANCE OF RESIDENTIAL AIR-TO-AIR HEAT EXCHANGERS: TEST METHODS AND RESULTS

    E-Print Network [OSTI]

    Fisk, William J.

    2013-01-01

    effectiveness and low pressure exchanger would drop of thisAluminum Flanges Pressure Tap Heat Exchanger Transition,therefore the pressure in the heat exchanger was slightly

  2. Performance Test and Energy Saving Analysis of a Heat Pipe Dehumidifier 

    E-Print Network [OSTI]

    Zhao, X.; Li, Q.; Yun, C.

    2006-01-01

    , Dehumidifier Heat Pipes for Rice Drying and Storage, 6th International Heat Pipe Symposium, 2000,Chiang Mai, Thailand [3] Xia Yu, Wen Wang, Ruzhu Wang. Applications of heat pipe in Air conditions)in Chinese). Heating Ventilation and Air Conditions,2004,34(5):26-30 ...

  3. Solar heat pump systems with refrigerant-filled collectors

    SciTech Connect (OSTI)

    O'Dell, M.P.; Beckman, W.A.; Mitchell, J.W.

    1983-01-01

    The heat pump system with a refrigerant-filled evaporator consists of a standard air-to-air or air-to-liquid heat pump that utilizes a solar panel as the evaporator. A combination of solar energy and convection heat transfer acts as the ''free'' energy absorbed by the collector/evaporator. In this paper, the seasonal performance of such systems for industrial applications will be presented. Performance of collector/evaporator heat pumps will be compared with alternative heat pump and solar systems. The benefits of covered and coverless collector/evaporators will be discussed. Results to date have shown that refrigerant-filled collector heat pumps do not perform as well as conventional heat pumps at small collector areas but have as much as 15% performance improvement over conventional heat pumps at an appropriate collector area.

  4. Geothermal Heat Pump Energy Savings Performance Contract at Fort Polk, LA: Lessons Learned

    SciTech Connect (OSTI)

    Hughes, Patrick; Shonder, John A; Gordon, Richard; Giffin, Tom

    1997-06-01

    At Fort Polk, Louisiana, the space-conditioning systems of 4,003 military family housing units have been converted to geothermal heat pumps (GHPs) under an energy savings performance contract. At the same time, other efficiency measures, such as compact fluorecent lights, low-flow shower heads, and attic insulation, were installed. An independent evaluation of the Fort Polk energy savings performance contract was carried out. Findings indicate that the project has resulted in a 25.6 million kWh savings in electrical energy use, or 32.4% of the pre-retrofit electrical consumption in family housing, for a typical meteorological year. Peak electrical demand has also been reduced by about 6,761 kW, which is 40.2% of the pre-retrofit peak demand. Natural gas savings are about 260,000 therms per year. In addition, the energy savings performance contract has allowed the Army to effectively cap its future expenditures for family housing HVAC maintenance at about 77% of its previous costs. Given these successful results, the Fort Polk performance contract can provide a model for other contracts in both the public and private sectors. The purpose of this paper is to outline the method by which the contract was engineed and implemented, both from the standpoint of the facility owner (the U.S. Army) and the energy services company that is carrying out the contract. The lessons learned from this experience should be useful to other owners, service companies, and investors in the implementation of future service contracts. It should be noted that the energy savings presented in this document are the 'apparent' energy savings observed in the monitored data and not to be mistaken for the 'contract' energy savings used as the basis for payments. To determine the 'contracted' energy savings, the 'apparent' energy savings may require adjustments for such things as changes in the indoor temperature performance criteria, additions of ceiling fans, and other factors.

  5. A quasi-3D analysis of the thermal performance of a flat heat pipe G. Carbajal a,*, C.B. Sobhan b

    E-Print Network [OSTI]

    Wadley, Haydn

    A quasi-3D analysis of the thermal performance of a flat heat pipe G. Carbajal a,*, C.B. Sobhan b form 29 January 2007 Available online 8 May 2007 Abstract The thermal performance of a flat heat pipe. The transient temperature distribution on a solid aluminum plate was compared with the flat heat pipe results

  6. Measured Performance and Analysis of Ground Source Heat Pumps for Space Conditioning and for Water Heating in a Low-Energy Test House Operated under Simulated Occupancy Conditions

    SciTech Connect (OSTI)

    Ally, Moonis Raza [ORNL] [ORNL; Munk, Jeffrey D [ORNL] [ORNL; Baxter, Van D [ORNL] [ORNL; Gehl, Anthony C [ORNL] [ORNL

    2012-01-01

    In this paper we present measured performance and efficiency metrics of Ground Source Heat Pumps (GSHPs) for space conditioning and for water heating connected to a horizontal ground heat exchanger (GHX) loop. The units were installed in a 345m2 (3700ft2) high-efficiency test house built with structural insulated panels (SIPs), operated under simulated occupancy conditions, and located in Oak Ridge, Tennessee (USA) in US Climate Zone 4 . The paper describes distinctive features of the building envelope, ground loop, and equipment, and provides detailed monthly performance of the GSHP system. Space conditioning needs of the house were completely satisfied by a nominal 2-ton (7.0 kW) water-to-air GSHP (WA-GSHP) unit with almost no auxiliary heat usage. Recommendations for further improvement through engineering design changes are identified. The comprehensive set of data and analyses demonstrate the feasibility and practicality of GSHPs in residential applications and their potential to help achieve source energy and greenhouse gas emission reduction targets set under the IECC 2012 Standard.

  7. Demonstration and Performance Monitoring of Foundation Heat Exchangers (FHX) in Ultra-High Energy Efficient Research Homes

    SciTech Connect (OSTI)

    Im, Piljae; Hughes, Patrick; Liu, Xiaobing

    2012-01-01

    The more widespread use of Ground Source Heat Pump (GSHP) systems has been hindered by their high first cost, which is mainly driven by the cost of the drilling and excavation for installation of ground heat exchangers (GHXs). A new foundation heat exchanger (FHX) technology was proposed to reduce first cost by placing the heat exchanger into the excavations made during the course of construction (e.g., the overcut for the basement and/or foundation and run-outs for water supply and the septic field). Since they reduce or eliminate the need for additional drilling or excavation, foundation heat exchangers have the potential to significantly reduce or eliminate the first cost premium associated with GSHPs. Since December 2009, this FHX technology has been demonstrated in two ultra-high energy efficient new research houses in the Tennessee Valley, and the performance data has been closely monitored as well. This paper introduces the FHX technology with the design, construction and demonstration of the FHX and presents performance monitoring results of the FHX after one year of monitoring. The performance monitoring includes hourly maximum and minimum entering water temperature (EWT) in the FHX compared with the typical design range, temperature difference (i.e., T) across the FHX, and hourly heat transfer rate to/from the surrounding soil.

  8. Field Performance of a Ground-Coupled Heat Pump in Abilene, Texas 

    E-Print Network [OSTI]

    Dobson, M.; O'Neal, D. L.; Aldred, W.; Margo, R.

    1994-01-01

    (COP), and ground-coil heat rejection. Data for operation in the cooling and heating mode are discussed here. Based on the experimental data, it was discovered that the water temperature entering the condenser (EWT) exhibited a prolonged minimum after...

  9. PERFORMANCE OF RESIDENTIAL AIR-TO-AIR HEAT EXCHANGERS: TEST METHODS AND RESULTS

    E-Print Network [OSTI]

    Fisk, William J.

    2013-01-01

    2. SCHEMATIC DIAGRAM OF A CROSSFLOW HEAT EXCHANGER. H RMED Rthe same direction. In a crossflow exchanger, (Fig- ure 2)Heat Exchanger (Figure 11) has a crossflow and core, two two

  10. Regional Variation in Residential Heat Pump Water Heater Performance in the U.S.: Preprint

    SciTech Connect (OSTI)

    Maguire, J.; Burch, J.; Merrigan, T.; Ong, S.

    2014-01-01

    Residential heat pump water heaters (HPWHs) have recently reemerged on the U.S. market. These units have the potential to provide homeowners significant cost and energy savings. However, actual in use performance of a HPWH will vary significantly with climate, installation location, HVAC equipment, and hot water use. To determine what actual in use energy consumption of a HPWH may be in different regions of the U.S., annual simulations of both 50 and 80 gallon HPWHs as well as a standard electric water heater were performed for over 900 locations across the U.S. The simulations included a benchmark home to take into account interactions between the space conditioning equipment and the HPWH and a realistic hot water draw profile. It was found that the HPWH will always save some source energy when compared to a standard electric resistance water heater, although savings varies widely with location. In addition to looking at source energy savings, the breakeven cost (the net installed cost a HPWH would have to have to be a cost neutral replacement for a standard water heater) was also examined. The highest breakeven costs were seen in cases with high energy savings, such as the southeastern U.S., or high energy costs, such as New England and California. While the breakeven cost is higher for 80 gallon units than 50 gallon units, the higher net installed costs of an 80 gallon unit lead to the 50 gallon HPWHs being more likely to be cost effective.

  11. Regional Variation in Residential Heat Pump Water Heater Performance in the U.S.

    SciTech Connect (OSTI)

    Maguire, Jeff; Burch, Jay; Merrigan, Tim; Ong, Sean

    2014-01-01

    Residential heat pump water heaters (HPWHs) have recently re-emerged on the U.S. market, and they have the potential to provide homeowners significant cost and energy savings. However, actual in use performance of a HPWH will vary significantly with climate, installation location, HVAC equipment, and hot water use. To determine the actual energy consumption of a HPWH in different U.S. regions, annual simulations of both 50 and 80 gallon HPWHs as well as a standard electric water heater were performed for over 900 locations across the United States. The simulations included a benchmark home to take into account interactions between the space conditioning equipment and the HPWH and a realistic hot water draw profile. It was found that the HPWH will always save some source energy when compared to a standard electric resistance water heater, although savings varies widely with location. In addition to looking at source energy savings, the breakeven cost (the net installed cost a HPWH would have to have to be a cost neutral replacement for a standard water heater) was also examined. The highest breakeven costs were seen in cases with high energy savings, such as the southeastern U.S., or high energy costs, such as New England and California. While the breakeven cost is higher for 80 gallon units than 50 gallon units, the higher net installed costs of an 80 gallon unit lead to the 50 gallon HPWHs being more likely to be cost effective.

  12. Study of Performance of Heat Pump Usage in Sewage Treatment and Fouling Impact on System 

    E-Print Network [OSTI]

    Song, Y.; Yao, Y.; Ma, Z.; Na, W.

    2006-01-01

    A heat pump using disposed sewage as a heat source to heat raw sewage is presented to solve the problem that sewage temperature is low in sewage biologic treatment in cold region. According to the status of one medicine factory in Harbin, China...

  13. Performance and evaluation of gas engine driven rooftop air conditioning equipment at the Willow Grove (PA) Naval Air Station. Interim report, 1992 cooling season

    SciTech Connect (OSTI)

    Armstrong, P.R.; Conover, D.R.

    1993-05-01

    In a field evaluation conducted for the US Department of Energy (DOE) Office of Federal Energy Management Program (FEMP), the Pacific Northwest Laboratory (PNL) examined the performance of a new US energy-related technology under the FEMP Test Bed Demonstration Program. The technology was a 15-ton natural gas engine driven roof top air conditioning unit. Two such units were installed on a naval retail building to provide space conditioning to the building. Under the Test Bed Demonstration Program, private and public sector interests are focused to support the installation and evaluation of new US technologies in the federal sector. Participating in this effort under a Cooperative Research and Development Agreement (CRADA) with DOE were the American Gas Cooling Center, Philadelphia Electric Company, Thermo King Corporation, and the US Naval Air Station at Willow Grove, Pennsylvania. Equipment operating and service data as well as building interior and exterior conditions were secured for the 1992 cooling season. Based on a computer assessment of the building using standard weather data, a comparison was made with the energy and operating costs associated with the previous space conditioning system. Based on performance during the 1992 cooling season and adjusted to a normal weather year, the technology will save the site $6,000/yr in purchased energy costs. An additional $9,000 in savings due to electricity demand ratchet charge reductions will also be realized. Detailed information on the technology, the installation, and the results of the technology test are provided to illustrate the advantages to the federal sector of using this technology. A history of the CRADA development process is also reported.

  14. Technology Solutions Case Study: Performance of a Heat Pump Water Heater in the Hot-Humid Climate, Windermere, Florida

    SciTech Connect (OSTI)

    2013-11-01

    Over recent years, heat pump water heaters (HPWHs) have become more readily available and more widely adopted in the marketplace. For a 6-month period, the Building America team Consortium for Advanced Residential Buildings monitored the performance of a GE Geospring HPWH in Windermere, Florida. The study found that the HPWH performed 144% more efficiently than a traditional electric resistance water heater, saving approximately 64% on water heating annually. The monitoring showed that the domestic hot water draw was a primary factor affecting the system's operating efficiency.

  15. Performance of a Heat Pump Water Heater in the Hot-Humid Climate, Windermere, Florida (Fact Sheet)

    SciTech Connect (OSTI)

    Metzger, C.; Puttagunta, S.; Williamson, J.

    2013-11-01

    Over recent years, heat pump water heaters (HPWHs) have become more readily available and more widely adopted in the marketplace. For a 6-month period, the Building America team Consortium for Advanced Residential Buildings monitored the performance of a GE Geospring HPWH in Windermere, Florida. The study found that the HPWH performed 144% more efficiently than a traditional electric resistance water heater, saving approximately 64% on water heating annually. The monitoring showed that the domestic hot water draw was a primary factor affecting the system's operating efficiency.

  16. Geothermal heat pump energy savings performance contract at Fort Polk, LA: Lessons learned

    SciTech Connect (OSTI)

    Shonder, J.A.; Hughes, P.J.; Gordon, R.; Giffin, T.

    1997-08-01

    At Fort Polk, LA the space conditioning systems of 4,003 military family housing units have been converted to geothermal heat pumps (GHP) under an energy savings performance contract (ESPC). At the same time, other efficiency measures, such as compact fluorescent lights (CFLs), low-flow shower heads, and attic insulation, were installed. An independent evaluation of the Fort Polk ESPC was carried out. Findings indicate that the project has resulted in a 25.6 million kWh savings in electrical energy use, or 32.4% of the pre-retrofit electrical consumption in family housing, for a typical meteorological year. Peak electrical demand has also been reduced by 6,541 kW, which is 39.6% of the pre-retrofit peak demand. Natural gas savings are about 260,000 therms per year. In addition, the ESPC has allowed the Army to effectively cap its future expenditures for family housing HVAC maintenance at about 77% of its previous costs. Given these successful results, the Fort Polk ESPC can provide a model for other ESPCs in both the public and the private sectors. The purpose of this paper is to outline the method by which the ESPC was engineered and implemented, both from the standpoint of the facility owner (the US Army) and the energy services company (ESCO) which is carrying out the contract. The lessons learned from this experience should be useful to other owners, ESCOs and investors in the implementation of future ESPCs. It should be noted that the energy savings presented in this document are the apparent energy savings observed in the monitored data, and are not to be confused with the contracted energy savings used as the basis for payments. To determine the contracted energy savings, the apparent energy savings may require adjustments for such things as changes in indoor temperature performance criteria, additions of ceiling fans, and other factors.

  17. Heat Pipe Performance Enhancement with Binary Mixture Fluids that Exhibit Strong Concentration Marangoni Effects

    E-Print Network [OSTI]

    Armijo, Kenneth Miguel

    2011-01-01

    two-phase thermosyphon solar water heater”, Energy, 36 , pp.thermal hybrid solar collector water heater”, Proc. ISESheaters simulated waste heat production of the respective PV solar

  18. Improving Process Heating System Performance: A Sourcebook for Industry, Second Edition

    SciTech Connect (OSTI)

    None

    2008-02-01

    This is one in a series of sourcebooks to help manufacturers optimize their industrial systems; this particular sourcebook addresses process heating systems.

  19. Heat Pipe Performance Enhancement with Binary Mixture Fluids that Exhibit Strong Concentration Marangoni Effects

    E-Print Network [OSTI]

    Armijo, Kenneth Miguel

    2011-01-01

    pipe energy generation devices. Thermo-electric evaluationpipe energy generation devices. Thermo-electric evaluationenergy for heating applications or thermal electric power generation [

  20. Multi-objective optimization of the HVAC (heating, ventilation, and air conditioning) system performance

    E-Print Network [OSTI]

    Kusiak, Andrew

    Multi-objective optimization of the HVAC (heating, ventilation, and air conditioning) system, ventilation, and air conditioning) system in a typical office facility is presented. A multi-layer perceptron. 1. Introduction HVAC (heating, ventilating and air conditioning) systems are designed to maintain

  1. THERMAL PERFORMANCE OF A DUAL-CHANNEL, HELIUM-COOLED, TUNGSTEN HEAT EXCHANGER

    E-Print Network [OSTI]

    California at Los Angeles, University of

    high heat fluxes. The high temperature helium can then be used to power a gas turbine for high. These refractory devices take advantage of high temperature operation with large delta-Ts to effectively handle helium flow loop at Sandia National Laboratories. The module survived a maximum absorbed heat flux of 34

  2. Geothermal Heat Pumps are Scoring High Marks

    SciTech Connect (OSTI)

    2000-08-01

    Geothermal Energy Program Office of Geothermal and Wind Technologies Geothermal Heat Pumps are Scoring High Marks Geothermal heat pumps, one of the clean energy technology stars Geothermal heat pumps (GHPs) are one of the most cost-effective heating, cooling, and water heating systems available for both residential and commercial buildings. GHPs extract heat from the ground during the heating season and discharge waste heat to the ground during the cooling season. The U.S. Environmental Protecti

  3. Monitored energy use of homes with geothermal heat pumps: A compilation and analysis of performance. Final report

    SciTech Connect (OSTI)

    Stein, J.R.; Meier, A.

    1997-12-01

    The performance of residential geothermal heat pumps (GHPs) was assessed by comparing heating, ventilation, and air conditioning (HVAC) system and whole house energy use of GHP houses and control houses. Actual energy savings were calculated and compared to expected savings (based on ARI ratings and literature) and predicted savings (based on coefficient of performance - COP - measurements). Differences between GHP and control houses were normalized for heating degree days and floor area or total insulation value. Predicted savings were consistently slightly below expected savings but within the range of performance cited by the industry. Average rated COP was 3.4. Average measured COP was 3.1. Actual savings were inconsistent and sometimes significantly below predicted savings. No correlation was found between actual savings and actual energy use. This suggests that factors such as insulation and occupant behavior probably have greater impact on energy use than type of HVAC equipment. There was also no clear correlation between climate and actual savings or between climate and actual energy use. There was a trend between GHP installation date and savings. Newer units appear to have lower savings than some of the older units which is opposite of what one would expect given the increase in rated efficiencies of GHPs. There are a number of explanations for why actual savings are repeatedly below rated savings or predicted savings. Poor ground loop sizing or installation procedures could be an issue. Given that performance is good compared to ASHPs but poor compared to electric resistance homes, the shortfall in savings could be due to duct leakage. The takeback effect could also be a reason for lower than expected savings. Occupants of heat pump homes are likely to heat more rooms and to use more air-conditioning than occupants of electric resistance homes. 10 refs., 17 figs., 10 tabs.

  4. Experimental study of an air-source heat pump for simultaneous heating and cooling Part 1: Basic concepts and performance verification

    E-Print Network [OSTI]

    Boyer, Edmond

    manufacturer. The operation of the high pressure control system, the transitions between heating, cooling1 Experimental study of an air-source heat pump for simultaneous heating and cooling ­ Part 1 40 51 ABSTRACT This article presents the concepts of an air-source Heat Pump for Simultaneous heating

  5. Open Season in Sacramento

    E-Print Network [OSTI]

    Brosnan, Douglas

    2009-01-01

    egislative Open Season in Sacramento Douglas Brosnan, MD, JDs open season again in Sacramento: The legislative session

  6. Influence of lubricant oil on heat transfer performance of refrigerant flow boiling inside small diameter tubes. Part I: Experimental study

    SciTech Connect (OSTI)

    Wei, Wenjian; Ding, Guoliang; Hu, Haitao; Wang, Kaijian

    2007-10-15

    Two-phase flow pattern and heat transfer characteristics of refrigerant-oil mixture flow boiling inside small tubes with inside diameters of 6.34 mm and 2.50 mm are investigated experimentally. The test condition of nominal oil concentration is from 0% to 5%, mass flux from 200 to 400 kg m{sup -2} s{sup -1}, heat flux from 3.2 to 14 kW m{sup -2}, evaporation temperature of 5 C, inlet quality from 0.1 to 0.8, and quality change from 0.1 to 0.2. Wavy, wavy-annular, annular and mist-annular flow pattern in 6.34 mm tube are observed, while only slug-annular and annular flow pattern are observed in 2.50 mm tube. Oil presence can make annular flow to form early and to retard to diminish in quality direction at nominal oil concentration {>=}3%. Augmentation effect of oil on heat transfer coefficient becomes weakened or even diminishes for small diameter tube while detrimental effect of oil on small tube performance becomes more significant than large tube. For both test tubes, variation of heat transfer coefficient and enhanced factor with oil concentration is irregular. Two-phase heat transfer multiplier with refrigerant-oil mixture properties increases consistently and monotonically with local oil concentration at different vapor quality. (author)

  7. Effect of lubricant on spray evaporation heat transfer performance of R-134a and R-22 in tube bundles

    SciTech Connect (OSTI)

    Moeykens, S.A.; Pate, M.B.

    1996-11-01

    This study evaluates the effects of lubricant on spray evaporation heat transfer performance. Tests were conducted with refrigerant R-134a and triangular-pitch tube bundles made from enhanced-condensation, enhanced-boiling, low-finned, and plain-surface tubes. A 340-SUS polyol-ester (POE) oil was used for the R-134a testing because this lubricant is being integrated into industry for use with this refrigerant. Refrigerant was sprayed onto the tube bundles with low-pressure-drop, wide-angle nozzles located directly above the bundle. Collector testing was conducted with both R-134a and R-22 to determine the percentage of refrigerant contacting the tue bundle. It was found that small concentrations of the polyol-ester lubricant yielded significant improvement in the heat transfer performance of R-134a. The shell-side heat transfer coefficient was more dependent on lubricant concentration than on film-feed supply rate within the range of the respective parameters evaluated in this study. As expected, pure R-22 results show higher heat transfer coefficients than those obtained with pure R-134a at the same saturation temperature of 2.0 C (35.6 F).

  8. Comparison of ICRF and NBI heated plasmas performances in the JET ITER-like wall

    SciTech Connect (OSTI)

    Mayoral, M.-L. [EFDA Close Support Unit, Garching, Germany and Euratom/CCFE Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Pütterich, T.; Bobkov, V. [Max-Planck-Institut für Plasmaphysik, EURATOM-Assoziation, Garching (Germany); Jacquet, P. [Euratom/CCFE Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Lerche, E.; Van-Eester, D.; Bourdelle, C.; Colas, L. [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Czarnecka, A. [Association Euratom-IPPLM, Hery 23, 01-497 Warsaw (Poland); Mlynar, J. [Association Euratom-IPP.CR, Institute of Plasma Physics AS CR, 18200 Prague (Czech Republic); Neu, R. [EFDA Close Support Unit, Garching, Germany and Max-Planck-Institut für Plasmaphysik, EURATOM-Assoziation, Garching (Germany); Collaboration: JET-EFDA Contributors

    2014-02-12

    During the initial operation of the JET ITER-like wall, particular attention was given to the characterization of the Ion Cyclotron Resonance Frequency (ICRF) heating in this new metallic environment. In this contribution we compare L-modes plasmas heated by ICRF or by Neutral Beam Injection (NBI). ICRF heating as expected led to a much higher centrally peaked power deposition on the electrons and due to the central fast ion population to stronger sawtooth activity. Surprisingly, although a higher bulk radiation was observed during the ICRF phase, the thermal plasma energy was found similar for both cases, showing that a higher radiation inside the separatrix was not incompatible with an efficient central heating scheme. The higher radiation was attributed to the presence Tungsten (W). Tomographic inversion of SXR emissions allowed a precise observation of the sawtooth effect on the radiation pattern. W concentration profiles deconvolved from SXR emission showed the flattening of the profiles due to sawtooth for both heating and the peaking of the profiles in the NBI case only hinting for extra transport effect in the ICRF case.

  9. Testing the ecological stability of ectomycorrhizal symbiosis: effects of heat, ash and mycorrhizal colonization on Pinus muricata seedling performance

    E-Print Network [OSTI]

    Peay, Kabir G.; Bruns, Thomas D.; Garbelotto, Matteo

    2010-01-01

    batch was subjected to heat treatments modified from Izzo etof the seedlings from each heat treatment were then randomlyresults show that heat treatments (which increase mineral N

  10. Improved Heat Transfer and Performance of High Intensity Combustion Systems for Reformer Furnace Applications 

    E-Print Network [OSTI]

    Williams, F. D. M.; Kondratas, H. M.

    1983-01-01

    Developments over the past fifteen years have evolved new short flame, high intensity (1,000,000 BTU/HR/ft3 ) combustion systems for industrial uses. Such systems produce a more uniform and higher heat flux than conventional low intensity systems...

  11. Numerical Simulation of Thermal Performance of Floor Radiant Heating System with Enclosed Phase Change Material 

    E-Print Network [OSTI]

    Qiu, L.; Wu, X.

    2006-01-01

    of the energy storage floor is designed,which places heat pipes in the enclosed phase change material (PCM) layer, without concrete in it. The PCM thermal storage time is studied in relation to the floor surface temperature under different low-temperature hot...

  12. Geothermal Heat Pump Basics

    Broader source: Energy.gov [DOE]

    Geothermal heat pumps use the constant temperature of the earth as an exchange medium for heat. Although many parts of the country experience seasonal temperature extremes—from scorching heat in the summer to sub-zero cold in the winter—the ground a few feet below the earth's surface remains at a relatively constant temperature.

  13. Building America Case Study: Field Performance of Inverter-Driven Heat Pumps in Cold Climates - Connecticut, Massachusetts, and Vermont

    SciTech Connect (OSTI)

    2015-09-01

    New inverter-driven ASHPs are gaining ground in colder climates. These systems operate at sub-zero temperatures without the use of electric resistance backup. There are still uncertainties, however, about cold-climate capacity and efficiency in cold weather and questions such as measuring: power consumption, supply, return, and outdoor air temperatures, and air flow through the indoor fan coil. CARB observed a wide range of operating efficiencies and outputs from site to site. Maximum capacities were found to be generally in line with manufacturer's claims as outdoor temperatures fell to -10 degrees F. The reasons for the wide range in heating performance likely include: low indoor air flow rates, poor placement of outdoor units, relatively high return air temperatures, thermostat set back, integration with existing heating systems, and occupants limiting indoor fan speed. Even with lower efficiencies than published in other studies, most of the heat pumps here still provide heat at lower cost than oil, propane, or certainly electric resistance systems.

  14. Experience with thermal storage in tanks of stratified water for solar heating and load management

    SciTech Connect (OSTI)

    Wildin, M.W.; Witkofsky, M.P.; Noble, J.M.; Hopper, R.E.; Stromberg, P.G.

    1982-01-01

    Results have been obtained for performance of stratified tanks of water used to store heating and cooling capacity in a 5574 m/sup 2/ university building. The major sources of energy used to charge the heated tanks were solar energy, obtained via collectors on the roof of the building, and excess heat recovered from the interior of the building via thermal storage and electric-driven heat pump/chillers. Through stratification of the water in the storage tanks and an appropriate system operating strategy, 40 percent of the building's total heating needs were supplied by solar energy during the first four months of 1981. Month-long thermal efficiencies of the storage array ranging from 70 percent during the heating season to nearly 90 percent during the cooling season, were measured. Work is underway to improve the performance of thermal storage.

  15. Topic 14. Retrofit and optimal operation of the building energy systems Performances of Low Temperature Radiant Heating Systems

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    , wall heating, floor heating, ceiling heating, EnergyPlus SUMMARY Low temperature heating panel systems. It is found that the floor-ceiling heating system has the lowest energy, exergy, CO2 emissions, operating and the surrounding areas, and the heat conduction between the floor and the ground. The main essence of the low

  16. Thermal hydraulic performance testing of printed circuit heat exchangers in a high-temperature helium test facility

    SciTech Connect (OSTI)

    Sai K. Mylavarapu; Xiaodong Sun; Richard E. Glosup; Richard N. Christensen; Michael W. Patterson

    2014-04-01

    In high-temperature gas-cooled reactors, such as a very high temperature reactor (VHTR), an intermediate heat exchanger (IHX) is required to efficiently transfer the core thermal output to a secondary fluid for electricity generation with an indirect power cycle and/or process heat applications. Currently, there is no proven high-temperature (750–800 °C or higher) compact heat exchanger technology for high-temperature reactor design concepts. In this study, printed circuit heat exchanger (PCHE), a potential IHX concept for high-temperature applications, has been investigated for their heat transfer and pressure drop characteristics under high operating temperatures and pressures. Two PCHEs, each having 10 hot and 10 cold plates with 12 channels (semicircular cross-section) in each plate are fabricated using Alloy 617 plates and tested for their performance in a high-temperature helium test facility (HTHF). The PCHE inlet temperature and pressure were varied from 85 to 390 °C/1.0–2.7 MPa for the cold side and 208–790 °C/1.0–2.7 MPa for the hot side, respectively, while the mass flow rate of helium was varied from 15 to 49 kg/h. This range of mass flow rates corresponds to PCHE channel Reynolds numbers of 950 to 4100 for the cold side and 900 to 3900 for the hot side (corresponding to the laminar and laminar-to-turbulent transition flow regimes). The obtained experimental data have been analyzed for the pressure drop and heat transfer characteristics of the heat transfer surface of the PCHEs and compared with the available models and correlations in the literature. In addition, a numerical treatment of hydrodynamically developing and hydrodynamically fully-developed laminar flow through a semicircular duct is presented. Relations developed for determining the hydrodynamic entrance length in a semicircular duct and the friction factor (or pressure drop) in the hydrodynamic entry length region for laminar flow through a semicircular duct are given. Various hydrodynamic entrance region parameters, such as incremental pressure drop number, apparent Fanning friction factor, and hydrodynamic entrance length in a semicircular duct have been numerically estimated.

  17. Seasonal Run Distribution Seasonal Run Distribution

    E-Print Network [OSTI]

    . The term "total run" defines the number of adult sockeye salmon that home to the Karluk River before197 Seasonal Run Distribution CHAPTER 6 Seasonal Run Distribution They arrived from the sea in one, what was the seasonal run distribution of its sockeye salmon? Was the original run distribution which

  18. New Whole-House Solutions Case Study: Testing Ductless Heat Pumps in High-Performance Affordable Housing, the Woods at Golden Given - Tacoma, Washington

    SciTech Connect (OSTI)

    2015-06-01

    The Woods is a 30-home, high- performance, energy efficient sustainable community built by Habitat for Humanity (HFH). With Support from Tacoma Public Utilities, Washington State University (part of the Building America Partnership for Improved Residential Construction) is researching the energy performance of these homes and the ductless heat pumps (DHP) they employ. This project provides Building America with an opportunity to: field test HVAC equipment, ventilation system air flows, building envelope tightness, lighting, appliance, and other input data that are required for preliminary Building Energy Optimization (BEopt™) modeling and ENERGY STAR® field verification; analyze cost data from HFH and other sources related to building-efficiency measures that focus on the DHP/hybrid heating system and heat recovery ventilation system; evaluate the thermal performance and cost benefit of DHP/hybrid heating systems in these homes from the perspective of homeowners; compare the space heating energy consumption of a DHP/electric resistance (ER) hybrid heating system to that of a traditional zonal ER heating system; conduct weekly "flip-flop tests" to compare space heating, temperature, and relative humidity in ER zonal heating mode to DHP/ER mode.

  19. Predicting yearly energy savings using BIN weather data with heat-pipe heat exchangers with indirect evaporative cooling

    SciTech Connect (OSTI)

    Mathur, G.D.

    1998-07-01

    Heat-Pipe Heat-Exchangers (HPHE) are passive systems that have recently seen application in energy recovery (Mathur, 1997). A HPHE consists of individual closed end heat pipe tubes that are charged with a suitable working fluid. In these systems, the working fluid evaporates on one side of the heat exchanger and condenses over the other end of the heat exchanger. The condensed fluid returns back to the evaporator section through the capillary action of the wick. The performance of a HPHE system can be improved by the raising the condenser portion of the heat exchanger which facilitates effective return of the condensate back to the evaporator. HPHE can be used with air conditioning systems as retrofits and in new applications. For retrofit applications, the operating costs are reduced because of the reduction in the energy (kWh) and peak demand (kW) consumptions. For new installations, the heating and cooling equipment can be of smaller capacity which will result in lower equipment and operating costs. During the summer season, indirect evaporative cooling can also be used to further enhance the performance of the air conditioning system. When operated during both the heating and cooling seasons, a HPHE yields four types of savings: (i) Heating equipment savings (ii) Cooling equipment savings (iii) Heating operating savings (iv) Cooling operating savings. Savings in the energy consumption for both heating and cooling were calculated with the HPHE for 30 cities with widely different climactic conditions. The payback periods for most of the cities were less than 1 year. If indirect evaporative cooling is used during the summer season, more energy savings would be realized on an yearly basis along with further reductions in the peak demand. In this paper, the author has simulated the performance of a HPHE with indirect evaporative cooling using the BIN weather data.

  20. Heat Pipe Performance Enhancement with Binary Mixture Fluids that Exhibit Strong Concentration Marangoni Effects

    E-Print Network [OSTI]

    Armijo, Kenneth Miguel

    2011-01-01

    2004, “Cooling of photovoltaic cells under concentratedSolar cells and optics for photovoltaic concentration”, Adamelectric performance of a photovoltaic cells by cooling and

  1. Experimental Investigation of the Effect Of Zeolite Coating Thickness on the Performance of a Novel Zeolite-Water Adsorption Heat Pump Module 

    E-Print Network [OSTI]

    Dawoud, B.; Hofle, P.; Chmielewski, S.

    2010-01-01

    is an extruded aluminum finned-tube heat exchanger coated with AQSOA-Z02 zeolite of Mitsubishi Plastics Incorporation (MPI). The effect of the Zeolite layer thickness (300 and 500 micrometers) on the performance of the heat pump module has been experimentally...

  2. Evaluation on Energy Performance of Heating Plant System Installed Energy Saving Technologies 

    E-Print Network [OSTI]

    Song, Y.; Akashi, Y.; Kuwahara, Y.; Baba, Y.; Iribe, M.

    2004-01-01

    -cooled before entering a refrigerating machine to raise the COP. The heat exchange between cooling water and returned chilled water, which comes from the production area, occurs. When the cooling water temperature is below 13 2 3 4 5 6 7 8 9 10 10 15 20 25... 30 35 Inlet Temperature of Cooling Water in Refrigerating Machine (C) COP Chilled Water (Turbo, 7C) Brine (Screw, 5C) Brine (Screw, -5C) Brine (Screw, -8C) Figure2. Relation between the COP and Cooling Water Temperature in Refrigerating Machine...

  3. Photovoltaic roof heat flux

    E-Print Network [OSTI]

    Samady, Mezhgan Frishta

    2011-01-01

    e l Atmosphere ceiling, back panel roof, exposed roof insideSAN DIEGO Photovoltaic Roof Heat Flux A Thesis submitted i no n Convection Exposed Roof Temperature Seasonal Temperature

  4. Field monitoring of a variable-speed integrated heat pump/water heating appliance

    SciTech Connect (OSTI)

    Fanney, A.H.

    1993-06-01

    The report describes the residence, heat pump system, and monitoring equipment. Results are presented which include comparison of the total electrical energy consumption of the residence prior to and after installation of the heat pump system, the portion of energy used by each end use within the residence, a comparison of the heat pump's energy consumption using a conventional watthour meter and an electronic digital power analyzer, and the hourly electrical demands imposed on the utility. The thermal performance of the heat pump system is reported on a monthly, seasonal, and annual basis using conventional performance indicators in addition to using an index, proposed by NIST, which quantifies the overall system performance of integrated appliances.

  5. Measured Effects of Retrofits - A Refrigerant Oil Additive and a Condenser Spray Device - On the Cooling Performance of a Heat Pump 

    E-Print Network [OSTI]

    Levins, W. P.; Sand, J. R.; Baxter, V. D.; Linkous, R. S.

    1996-01-01

    A 15-year old, 3-ton single package air-to-air heat pump was tested in laboratory environmental chambers simulating indoor and outdoor conditions. After documenting initial performance, the unit was retrofitted with a prototype condenser water...

  6. Water and Space Heating Heat Pumps 

    E-Print Network [OSTI]

    Kessler, A. F.

    1985-01-01

    This paper discusses the design and operation of the Trane Weathertron III Heat Pump Water Heating System and includes a comparison of features and performance to other domestic water heating systems. Domestic water is generally provided through...

  7. Performance evaluation of the site built trickle solar collector system to heat swimming pool

    SciTech Connect (OSTI)

    Lee, J.H.; Park, W.H.; Park, K.S.

    1985-01-01

    This report discusses the analysis and field experiment conducted to determine the thermal performance of a particular trickle water collector design. Specific areas examined include the effect of the aspect ratio, flow rate and tilt angle on the collector performance. The exact solar radiation on the sinusoidal absorber plate has to be theoretically calculated. The influence of various design parameters such as corrugation height and width, distance between cover and absorber, tilt angle, and flow rate on the performance is rather small. For a small temperature increase between fluid inlet and outlet the agreement between experimental and theoretical results appears to be reasonable. However, for the higher fluid inlet temperature, and for larger temperature increase, the actual collector efficiency deviates significantly to indicate the necessity of a correction factor such as fogging on the cover plate to the theoretical consideration.

  8. Field monitoring of a variable-speed integrated heat pump/water-heating appliance

    SciTech Connect (OSTI)

    Fanney, A.H. [National Inst. of Standards and Technology, Gaithersburg, MD (United States). Building and Fire Research Lab.

    1995-12-31

    A variable-speed integrated heat pump/water-heating appliance was monitored for two years while meeting the space-conditioning and water-heating needs of an occupied residence. Experimental results are presented that show the total energy consumed by the residence was significantly reduced compared to previous years in which electric base-board heat, a wood stove, and window air conditioners were used. During the two space-heating seasons, the variable-speed integrated heat pump/water-heating appliance used 60% less energy than would have been consumed by an electric furnace with the same air distribution system and a storage-type electric water heater. The monthly space-cooling-only coefficients of performance (COP) ranged from 2.50 to 4.03, whereas the monthly space-heating-only coefficients of performance ranged from a low of 0.91 to a high of 3.33. A proposed index to quantify the overall system performance of integrated water-heating/space-conditioning appliances, referred to as the combined performance factor, ranged from 1.55 to 3.50. The majority of larger values occurred during months in which space cooling dominated. The combined performance factor for the entire two-year study was 2.45. A conventional watt-hour meter supplied by the local electrical utility and an electronic digital power analyzer were used to measure the energy consumption of the variable-speed heat pump to discern if variable-speed equipment introduces errors in conventional utility metering equipment. Measurements made using the two instruments were in excellent agreement. The monthly energy consumption and peak electrical demands of the residence, integrated heat pump/water-heating appliance, supplemental space heater, and water heater are discussed. The influence of outdoor temperature on electrical power demand is presented.

  9. DCH-2: Results from the second experiment performed in the Surtsey Direct Heating Test Facility

    SciTech Connect (OSTI)

    Tarbell, W.W.; Nichols, R.T.; Brockmann, J.E.; Ross, J.W.; Oliver, M.S.; Lucero, D.A.

    1988-01-01

    This test involved 80 kg of molten core debris simulant ejected under pressure into a 1:10 linear scale model of a reactor cavity. The apparatus was placed in the Surtsey Direct Heating Test Facility to allow direct measurement of the temperature and pressure rise of the contained atmosphere. The molten material was ejected from the cavity as a dense cloud of particles and gas. The dispersed debris caused a rapid pressurization of the 103-m/sup 3/ atmosphere. Peak pressures ranged from 0.22 to 0.31 MPa above the ambient level. Peak temperatures were from 759/sup 0/C to 1335/sup 0/C, with the highest values recorded near the top of the chamber. Much of the debris (approx.70%) was found adhered to the top and sides of the steel chamber. The pattern of the retained material suggested that the debris field propagated around the chamber following the contour of the vessel. Aerosol measurements indicated that approx.1% to approx.6.6% of the ejected mass was in the size range less than 10..mu..m aerodynamic diameter. 8 refs., 28 figs., 6 tabs.

  10. Performance Evaluation of a ground source heat pump system based on ANN and ANFIS models 

    E-Print Network [OSTI]

    Sun, W.; Hu, P.; Lei, F.; Zhu, N.; Zhang,J.

    2014-01-01

    .H DONG," MATLAB neural network and application," Beijing: National Defense Industry Press, 2005. [10] S. A. Kalogirou, "Applications of artificial neural networks in energy systems," Energy Conversion and Management, vol. 40, pp. 1073-1087, 1999. [11... stream_source_info ESL-IC-14-09-38.pdf.txt stream_content_type text/plain stream_size 28204 Content-Encoding UTF-8 stream_name ESL-IC-14-09-38.pdf.txt Content-Type text/plain; charset=UTF-8 Performance evaluation of a...

  11. MEASURED SPACE CONDITIONING PERFORMANCE OFA VERTICAL-BORE GROUND SOURCE HEAT PUMP (GSHP) OVER TWELVE MONTHS UNDER SIMULATED OCCUPANCY LOADS

    SciTech Connect (OSTI)

    Ally, Moonis Raza [ORNL; Munk, Jeffrey D [ORNL; Baxter, Van D [ORNL; Gehl, Anthony C [ORNL

    2014-01-01

    This paper presents monthly performance metrics of a 7.56 kW (2.16 ton) GSHP serving the space conditioning loads of a 251m2 (2700ft2) residential home with a phase change material in its envelope, and a single vertical-bore 94.5m (310 ft) ground loop. The same ground loop also serviced a ground source heat pump water heater. Envelope characteristics are discussed briefly in the context of reducing thermal losses. Data on entering water temperatures, energy extracted from the ground, energy delivered/removed, compressor electricity use, COP, GSHP run times (low and high compressor stages), and the impact of fan and pump energy consumption on efficiency are presented for each month. Both practical as well as research and development issues are discussed. The findings suggest that GSHPs represent a practical technology option to reduce source energy reduction and greenhouse emissions under the IECC 2012 Standard, as well as the European Union (EU) 2020 target of generating over 25% of heat consumed in the EU from renewable energy.

  12. Performance of AGR-1 High-Temperature Reactor Fuel During Post-Irradiation Heating Tests

    SciTech Connect (OSTI)

    Morris, Robert Noel [ORNL; Baldwin, Charles A [ORNL; Hunn, John D [ORNL; Demkowicz, Paul [Idaho National Laboratory (INL); Reber, Edward [Idaho National Laboratory (INL)

    2014-01-01

    The fission product retention of irradiated low-enriched uranium oxide/uranium carbide TRISO fuel compacts from the AGR-1 experiment has been evaluated at temperatures of 1600 1800 C during post-irradiation safety tests. Fourteen compacts (a total of ~58,000 particles) with a burnup ranging from 13.4 to 19.1% FIMA have been tested using dedicated furnace systems at Idaho National Laboratory and Oak Ridge National Laboratory. The release of fission products 110mAg, 134Cs, 137Cs, 154Eu, 155Eu, 90Sr, and 85Kr was monitored while heating the fuel specimens in flowing helium. The behavior of silver, europium, and strontium appears to be dominated by inventory that was originally released through intact SiC coating layers during irradiation, but was retained in the compact at the end of irradiation and subsequently released during the safety tests. However, at a test temperature of 1800 C, the data suggest that release of these elements through intact coatings may become significant after ~100 h. Cesium was very well retained by intact SiC layers, with a fractional release <5 10-6 after 300 h at 1600 C or 100 h at 1800 C. However, it was rapidly released from individual particles if the SiC layer failed, and therefore the overall cesium release fraction was dominated by the SiC defect and failure fractions in the fuel compacts. No complete TRISO coating layer failures were observed after 300 h at 1600 or 1700 C, and 85Kr release was very low during the tests (particles with breached SiC, but intact outer pyrocarbon, retained most of their krypton). Krypton release from TRISO failures was only observed after ~210 h at 1800 C in one compact. Post-safety-test examination of fuel compacts and particles has focused on identifying specific particles from each compact with notable fission product release and detailed analysis of the coating layers to understand particle behavior.

  13. Propane - A Mid-Heating Season Assessment

    Reports and Publications (EIA)

    2001-01-01

    This report will analyze some of the factors leading up to the rapid increase in propane demand and subsequent deterioration in supply that propelled propane prices to record high levels during December and early January.

  14. Nebraska Preparing for the Upcoming Heating Season

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet) Wyoming963Residential2,2,435,2226 (next releaseUnderground StorageReservesN E B

  15. Microsoft Word - Heating Oil Season.docx

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergyTher i nAand DOE SafetyofDepartment

  16. Estimated Maintenance Cost Savings from a Geothermal Heat Pump Energy Savings Performance Contract at Fort Polk, LA

    SciTech Connect (OSTI)

    Shonder, John A; Hughes, Patrick

    1997-06-01

    At Fort Polk, Louisiana, the space-conditioning systems of an entire city (4,003 military family housing units) have been converted to geothermal heat pumps (GHPs) under an energy savings performance contract. At the same time, other efficiency measures, such as compact fluorescent lights, low-flow hot water outlets, and attic insulation, were installed. These retrofits were performed by an energy services company at no up-front cost to the Army. The company has also assumed responsibility for maintenance of all equipment installed. In return, it receives a percentage of the energy and maintenance savings realized by the Army. In developing the energy savings performance contract, the Army estimated its pre-retrofit maintenance costs from bids received on a request for proposals. In this paper, a more rigorous cost estimate is developed, based on a survey of maintenance records for the pre-retrofit HVAC equipment. The reliability of the equipment is also estimated using an actuarial method to determine the number of units requiring replacement each year and the effect of these replacements on annual maintenance costs.

  17. Estimated maintenance cost savings from a geothermal heat pump energy savings performance contract at Fort Polk, Louisiana

    SciTech Connect (OSTI)

    Shonder, J.A.; Hughes, P.J.

    1997-12-31

    At Fort Polk, Louisiana, the space-conditioning systems of an entire city (4,003 military family housing units) have been converted to geothermal heat pumps (GHPs) under an energy savings performance contract. At the same time, other efficiency measures, such as compact fluorescent lights, low-flow hot water outlets, and attic insulation, were installed. These retrofits were performed by an energy services company at no up-front cost to the Army. The company has also assumed responsibility for maintenance of all the equipment installed. In return, it receives a percentage of the energy and maintenance savings realized by the Army. In developing the energy savings performance contract, the Army estimated its pre-retrofit maintenance costs from bids received on a request for proposals. In this paper, a more rigorous cost estimate is developed, based on a survey of maintenance records for the pre-retrofit HVAC equipment. The reliability of the equipment is also estimated using an actuarial method to determine the number of units requiring replacement each year and the effect of these replacements on annual maintenance costs.

  18. Cooperative heat transfer and ground coupled storage system

    DOE Patents [OSTI]

    Metz, Philip D. (Rocky Point, NY)

    1982-01-01

    A cooperative heat transfer and ground coupled storage system wherein collected solar heat energy is ground stored and permitted to radiate into the adjacent ground for storage therein over an extended period of time when such heat energy is seasonally maximally available. Thereafter, when said heat energy is seasonally minimally available and has propagated through the adjacent ground a substantial distance, the stored heat energy may be retrieved by a circumferentially arranged heat transfer means having a high rate of heat transfer.

  19. ITP Industrial Distributed Energy: Combined Heat & Power Multifamily Performance Program-- Sea Park East 150 kW CHP System

    Broader source: Energy.gov [DOE]

    Overview of Sea Park East 150 kilowatt (kW) Combined Heat and Power (CHP) System in Brooklyn, New York

  20. Design and Analysis of High-Performance Air-Cooled Heat Exchanger with an Integrated Capillary-Pumped Loop Heat Pipe

    E-Print Network [OSTI]

    McCarthy, Matthew

    We report the design and analysis of a high-power air-cooled heat exchanger capable of dissipating over 1000 W with 33 W of input electrical power and an overall thermal resistance of less than 0.05 K/W. The novelty of the ...

  1. Electrical energy and demand savings from a geothermal heat pump energy savings performance contract at Ft. Polk, LA

    SciTech Connect (OSTI)

    Shonder, J.A.; Hughes, P.J.

    1997-06-01

    At Fort Polk, LA the space conditioning systems of an entire city (4,003 military family housing units) have been converted to geothermal heat pumps (GHP) under an energy savings performance contract. At the same time, other efficiency measures such as compact fluorescent lights (CFLs), low-flow hot water outlets, and attic insulation were installed. Pre- and post-retrofit data were taken at 15-minute intervals on energy flows through the electrical distribution feeders that serve the family housing areas of the post. 15-minute interval data was also taken on energy use from a sample of the residences. This paper summarizes the electrical energy and demand savings observed in this data. Analysis of feeder-level data shows that for a typical year, the project will result in a 25.6 million kWh savings in electrical energy use, or 32.4% of the pre-retrofit electrical consumption in family housing. Results from analysis of building-level data compare well with this figure. Analysis of feeder-level data also shows that the project has resulted in a reduction of peak electrical demand of 6,541 kW, which is 39.6% of the pre-retrofit peak electrical demand. In addition to these electrical savings, the facility is also saving an estimated 260,000 therms per year of natural gas. It should be noted that the energy savings presented in this document are the apparent energy savings observed in the monitored data, and are not to be confused with the contracted energy savings used as the basis for payments. To determine the contracted energy savings, the apparent energy savings may require adjustments for such things as changes in indoor temperature performance criteria, additions of ceiling fans, and other factors.

  2. The Impact of Refrigerant Charge, Air Flow and Expansion Devices on the Measured Performance of an Air-Source Heat Pump Part I

    SciTech Connect (OSTI)

    Shen, Bo [ORNL

    2011-01-01

    This paper describes extensive tests performed on a 3-ton R-22 split heat pump in heating mode. The tests contain 150 steady-state performance tests, 18 cyclic tests and 18 defrost tests. During the testing work, the refrigerant charge level was varied from 70 % to 130% relative to the nominal value; the outdoor temperature was altered by three levels at 17 F (-8.3 C), 35 F (1.7 C) and 47 F (8.3 C); indoor air flow rates ranged from 60% to 150% of the rated air flow rate; and the expansion device was switched from a fixed-orifice to a thermal expansion value. Detailed performance data from the extensive steady state cyclic and defrost testing performed were presented and compared.

  3. Advanced Heat Transfer Technologies Increase Vehicle Performance and Reliability; The Spectrum of Clean Energy Innovation (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2010-06-01

    Fact sheet describes NREL's work with heat transfer technologies to keep hybrid electric and all-electric vehicle power electronic components cool.

  4. Influences of peripherally-cut twisted tape insert on heat transfer and thermal performance characteristics in laminar and turbulent tube flows

    SciTech Connect (OSTI)

    Eiamsa-ard, Smith [Department of Mechanical Engineering, Faculty of Engineering, Mahanakorn University of Technology, Bangkok 10530 (Thailand); Seemawute, Panida [Department of Civil Engineering, Faculty of Engineering, Mahanakorn University of Technology, Bangkok 10530 (Thailand); Wongcharee, Khwanchit [Department of Chemical Engineering, Faculty of Engineering, Mahanakorn University of Technology, Bangkok 10530 (Thailand)

    2010-09-15

    Effects of peripherally-cut twisted tape insert on heat transfer, friction loss and thermal performance factor characteristics in a round tube were investigated. Nine different peripherally-cut twisted tapes with constant twist ratio (y/W = 3.0) and different three tape depth ratios (DR = d/W = 0.11, 0.22 and 0.33), each with three different tape width ratios (WR = w/W = 0.11, 0.22 and 0.33) were tested. Besides, one typical twisted tape was also tested for comparison. The measurement of heat transfer rate was conducted under uniform heat flux condition while that of friction factor was performed under isothermal condition. Tests were performed with Reynolds number in a range from 1000 to 20,000, using water as a working fluid. The experimental results revealed that both heat transfer rate and friction factor in the tube equipped with the peripherally-cut twisted tapes were significantly higher than those in the tube fitted with the typical twisted tape and plain tube, especially in the laminar flow regime. The higher turbulence intensity of fluid in the vicinity of the tube wall generated by the peripherally-cut twisted tape compared to that induced by the typical twisted tape is referred as the main reason for achieved results. The obtained results also demonstrated that as the depth ratio increased and width ratio decreased, the heat transfer enhancement increased. Over the range investigated, the peripherally-cut twisted tape enhanced heat transfer rates in term of Nusselt numbers up to 2.6 times (turbulent regime) and 12.8 times (laminar regime) of that in the plain tube. These corresponded to the maximum performance factors of 1.29 (turbulent regime) and 4.88 (laminar regime). (author)

  5. Analysis of Electricity Usage for Domestic Heating Based on an Air-To-Water Heat Pump

    E-Print Network [OSTI]

    Treur, Jan

    Analysis of Electricity Usage for Domestic Heating Based on an Air-To-Water Heat Pump in a Real of an air to water heat pump in relation to outdoor temperatures is proposed and evaluated. This model into account. Real empirical data for usage of a heat pump over a whole heating season have been used to obtain

  6. Bayonet heat exchangers in heat-assisted Stirling heat pump

    SciTech Connect (OSTI)

    Yagyu, S.; Fukuyama, Y.; Morikawa, T.; Isshiki, N.; Satoh, I.; Corey, J.; Fellows, C.

    1998-07-01

    The Multi-Temperature Heat Supply System is a research project creating a city energy system with lower environmental load. This system consists of a gas-fueled internal combustion engine and a heat-assisted Stirling heat pump utilizing shaft power and thermal power in a combination of several cylinders. The heat pump is mainly driven by engine shaft power and is partially assisted by thermal power from engine exhaust heat source. Since this heat pump is operated by proportioning the two energy sources to match the characteristics of the driving engine, the system is expected to produce cooling and heating water at high COP. This paper describes heat exchanger development in the project to develop a heat-assisted Stirling heat pump. The heat pump employs the Bayonet type heat exchangers (BHX Type I) for supplying cold and hot water and (BHX Type II) for absorbing exhaust heat from the driving engine. The heat exchanger design concepts are presented and their heat transfer and flow loss characteristics in oscillating gas flow are investigated. The main concern in the BHX Type I is an improvement of gas side heat transfer and the spirally finned tubes were applied to gas side of the heat exchanger. For the BHX Type II, internal heat transfer characteristics are the main concern. Shell-and-tube type heat exchangers are widely used in Stirling machines. However, since brazing is applied to the many tubes for their manufacturing processes, it is very difficult to change flow passages to optimize heat transfer and loss characteristics once they have been made. The challenge was to enhance heat transfer on the gas side to make a highly efficient heat exchanger with fewer parts. It is shown that the Bayonet type heat exchanger can have good performance comparable to conventional heat exchangers.

  7. Comparison of the thermal performances of two nanofluids at low temperature in a plate heat Thierry Mar *a

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    heat, exchanger of heat plates, pressure drop, experimental. 1. Introduction The efforts aiming exchanger Thierry Maré *a Salma Halelfadl a Ousmane Sow b , Patrice Estellé c , Steven Duret d , Frederic aforementioned nanofluids. An assessment of the pressure drops in the circuit as well as of the powers

  8. Influence of lubricant oil on heat transfer performance of refrigerant flow boiling inside small diameter tubes. Part II: Correlations

    SciTech Connect (OSTI)

    Wei, Wenjian; Ding, Guoliang; Hu, Haitao; Wang, Kaijian

    2007-10-15

    The predictive ability of the available state-of-the-art heat transfer correlations of refrigerant-oil mixture is evaluated with the present experiment data of small tubes with inside diameter of 6.34 mm and 2.50 mm. Most of these correlations can be used to predict the heat transfer coefficient of 6.34 mm tube, but none of them can predict heat transfer coefficient of 2.50 mm tube satisfactorily. A new correlation of two-phase heat transfer multiplier with local properties of refrigerant-oil mixture is developed. This correlation approaches the actual physical mechanism of flow boiling heat transfer of refrigerant-oil mixture and can reflect the actual co-existing conditions of refrigerant and lubricant oil. More than 90% of the experiment data of both test tubes have less than {+-}20% deviation from the prediction values of the new correlations. (author)

  9. Heat Pump for High School Heat Recovery 

    E-Print Network [OSTI]

    Huang, K.; Wang, H.; Zhou, X.

    2006-01-01

    The heat pump system used for recycling and reusing waste heat in s high school bathroom was minutely analyzed in its coefficient of performance, onetime utilization ratio of energy, economic property and so on. The results showed that this system...

  10. Optimal artificial neural network architecture selection for performance prediction of compact heat exchanger with the EBaLM-OTR technique

    SciTech Connect (OSTI)

    Dumidu Wijayasekara; Milos Manic; Piyush Sabharwall; Vivek Utgikar

    2011-07-01

    Artificial Neural Networks (ANN) have been used in the past to predict the performance of printed circuit heat exchangers (PCHE) with satisfactory accuracy. Typically published literature has focused on optimizing ANN using a training dataset to train the network and a testing dataset to evaluate it. Although this may produce outputs that agree with experimental results, there is a risk of over-training or overlearning the network rather than generalizing it, which should be the ultimate goal. An over-trained network is able to produce good results with the training dataset but fails when new datasets with subtle changes are introduced. In this paper we present EBaLM-OTR (error back propagation and Levenberg-Marquardt algorithms for over training resilience) technique, which is based on a previously discussed method of selecting neural network architecture that uses a separate validation set to evaluate different network architectures based on mean square error (MSE), and standard deviation of MSE. The method uses k-fold cross validation. Therefore in order to select the optimal architecture for the problem, the dataset is divided into three parts which are used to train, validate and test each network architecture. Then each architecture is evaluated according to their generalization capability and capability to conform to original data. The method proved to be a comprehensive tool in identifying the weaknesses and advantages of different network architectures. The method also highlighted the fact that the architecture with the lowest training error is not always the most generalized and therefore not the optimal. Using the method the testing error achieved was in the order of magnitude of within 10{sup -5} - 10{sup -3}. It was also show that the absolute error achieved by EBaLM-OTR was an order of magnitude better than the lowest error achieved by EBaLM-THP.

  11. Analysis of Energy-Rescued Potential of a Hot Water Heating Network 

    E-Print Network [OSTI]

    Han, J.; Wang, D.; Tian, G.

    2006-01-01

    and electricity factory in Jinan, we analyze the energy waste caused by hydraulic power maladjustment and improper control of heating temperature in heating season. We conclude that proper adjustment of the heating network and controlling the heating supply...

  12. Hodges residence: performance of a direct gain passive solar home in Iowa

    SciTech Connect (OSTI)

    Hodges, L.

    1980-01-01

    Results are presented for the performance of the Hodges residence, a 2200-square-foot earth-sheltered direct gain passive solar home in Ames, Iowa, during the 1979-80 heating season, its first occupied season. No night insulation was used on its 500 square feet of double-pane glass. Total auxiliary heat required was 43 GJ (41 MBtu) gross and 26 GJ (25 MBtu) net, amounting, respectively, to 60 and 36 kJ/C/sup 0/-day-m/sup 2/ (2.9 and 1.8 Btu/F/sup 0/-day-ft/sup 2/). The heating season was unusually cloudy and included the cloudiest January in the 21 years of Ames insolation measurements. Results are also presented for the performance of the hollowcore floor which serves as the main storage mass and for the comfort range in the house.

  13. Hodges residence: performance of a direct gain passive solar home in Iowa

    SciTech Connect (OSTI)

    Hodges, L.

    1980-01-01

    Results are presented for the performance of the Hodges Residence, a 2200-square-foot earth-sheltered direct gain passive solar home in Ames, Iowa, during the 1979-80 heating season, its first occupied season. No night insulation was used on its 500 square feet of double-pane glass. Total auxiliary heat required was 43 GJ (41 MBTU) gross and 26 GJ (25 MBTU) net, amounting, respectively, to 60 and 36 kJ/C/sup 0/-day-m/sup 2/ (2.9 and 1.8 BTU/F/sup 0/-day-ft/sup 2/). The heating season was unusually cloudy and included the cloudiest January in the 21 years of Ames insolation measurements. Results are also presented for the performance of the hollow-core floor which serves as the main storage mass and for the comfort range in the house.

  14. CHP in ESPC: Implementing Combined Heat and Power Technologies Using Energy Savings Performance Contracts (ESPCs): Webinar Transcript

    Broader source: Energy.gov [DOE]

    Kurmit Rockwell:Welcome.  I'm Kurmit Rockwell, the ESPC Program Manager for DOE's Federal Energy Management Program.  In this presentation we will introduce you to the basics of combined heat and...

  15. Thermal Performance of a Novel Heat Transfer Fluid Containing Multiwalled Carbon Nanotubes and Microencapsulated Phase Change Materials 

    E-Print Network [OSTI]

    Tumuluri, Kalpana

    2011-08-08

    The present research work aims to develop a new heat transfer fluid by combining multiwalled carbon nanotubes (MWCNT) and microencapsulated phase change materials (MPCMs). Stable nanofluids have been prepared using different sizes of multiwalled...

  16. A comparison of the heat transfer and pressure drop performance of R-134a-lubricant mixtures in different diameter smooth tubes and micro-fin tubes

    SciTech Connect (OSTI)

    Eckels, S.J.; Doerr, T.M.; Pate, M.B.

    1998-10-01

    The average heat transfer coefficients and pressure drops during evaporation and condensation are reported for mixtures of R-134a and an ester lubricant in tubes of 12.7 mm (1/2 in.) outer diameter. The objective of this paper is to evaluate the performance of the R-134a-lubricant mixtures in these tubes and determine the performance benefits of the micro-fin tube. The performance benefits of the tubes with 12.7 mm (1/2 in.) outer diameter are compared to those of smaller tubes with 9.52 mm (3/8 in.) outer diameter. The lubricant used was a 169 SUS penta erythritol ester mixed-acid lubricant. The lubricant concentration was varied from 0--5.1% in the mixture. The average heat transfer coefficients in the 12.7 mm (1/2 in.) micro-fin tube were 50--150% higher than those for the 12.7 mm (1/2 in.) smooth tube, while pressure drops in the micro-fin tube were 5% to 50% higher than in the smooth tube. The addition of lubricant degraded the average heat transfer coefficients in all cases except during evaporation at low lubricant concentrations. Pressure drops were always increased with the addition of lubricant. The experimental results also indicate that tube diameter has some effect on the performance benefits of the micro-fin tube over that of the smooth tube.

  17. The Third Season of Rape

    E-Print Network [OSTI]

    Ahmed, Ali Jimale

    1988-01-01

    UFAHAMU THE THIRD SEASON OF RAPE by Ali Jimale Ahmed Andin the third season of rape. ·Somali for blood-sucking

  18. The Second Season of Rape

    E-Print Network [OSTI]

    Keynan, Hassan A.

    1988-01-01

    POETRY THE SECOND SEASON OF RAPE by Hassan A Keynan I datedFor the second season of Rape. Then, in her womb, did I

  19. Thermal barrier coatings: Coating methods, performance, and heat engine applications. (Latest citations from the EI Compendex*plus database). Published Search

    SciTech Connect (OSTI)

    1997-02-01

    The bibliography contains citations concerning conference proceedings on coating methods, performance evaluations, and applications of thermal barrier coatings as protective coatings for heat engine components against high temperature corrosions and chemical erosions. The developments of thermal barrier coating techniques for high performance and reliable gas turbines, diesel engines, jet engines, and internal combustion engines are presented. Topics include plasma sprayed coating methods, yttria stabilized zirconia coatings, coating life models, coating failure and durability, thermal shock and cycling, and acoustic emission analysis of coatings. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  20. Thermal barrier coatings: Coating methods, performance, and heat engine applications. (Latest citations from the EI Compendex*plus database). Published Search

    SciTech Connect (OSTI)

    Not Available

    1994-11-01

    The bibliography contains citations concerning conference proceedings on coating methods, performance evaluations, and applications of thermal barrier coatings as protective coatings for heat engine components against high temperature corrosions and chemical erosions. The developments of thermal barrier coating techniques for high performance and reliable gas turbines, diesel engines, jet engines, and internal combustion engines are presented. Topics include plasma sprayed coating methods, yttria stabilized zirconia coatings, coating life models, coating failure and durability, thermal shock and cycling, and acoustic emission analysis of coatings. (Contains a minimum of 243 citations and includes a subject term index and title list.)

  1. Thermal barrier coatings: Coating methods, performance, and heat engine applications. (Latest citations from the EI compendex*plus database). Published Search

    SciTech Connect (OSTI)

    Not Available

    1993-11-01

    The bibliography contains citations concerning conference proceedings on coating methods, performance evaluations, and applications of thermal barrier coatings as protective coatings for heat engine components against high temperature corrosions and chemical erosions. The developments of thermal barrier coating techniques for high performance and reliable gas turbines, diesel engines, jet engines, and internal combustion engines are presented. Topics include plasma sprayed coating methods, yttria stabilized zirconia coatings, coating life models, coating failure and durability, thermal shock and cycling, and acoustic emission analysis of coatings. (Contains 250 citations and includes a subject term index and title list.)

  2. Thermal barrier coatings: Coating methods, performance, and heat engine applications. (Latest citations from the EI Compendex*plus database). Published Search

    SciTech Connect (OSTI)

    1995-11-01

    The bibliography contains citations concerning conference proceedings on coating methods, performance evaluations, and applications of thermal barrier coatings as protective coatings for heat engine components against high temperature corrosions and chemical erosions. The developments of thermal barrier coating techniques for high performance and reliable gas turbines, diesel engines, jet engines, and internal combustion engines are presented. Topics include plasma sprayed coating methods, yttria stabilized zirconia coatings, coating life models, coating failure and durability, thermal shock and cycling, and acoustic emission analysis of coatings. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  3. Contamination effects on the performance of a heat pump charged with R-407C and POE lubricant 

    E-Print Network [OSTI]

    Fitzhenry, Shane Alan

    1996-01-01

    the high temperature heating and high temperature cooling tests increased by as much as 1822.5 Btuh (534 W) when mineral oil contamination of at least 5.6% was present in the first system, The final phase of the project examined the effects of water...

  4. Impacts of Soil and Pipe Thermal Conductivity on Performance of Horizontal Pipe in a Ground-source Heat Pump 

    E-Print Network [OSTI]

    Song, Y.; Yao, Y.; Na, W.

    2006-01-01

    In this paper the composition and thermal property of soil are discussed. The main factors that impact the soil thermal conductivity and several commonly-used pipe materials are studied. A model of heat exchanger with horizontal pipes of ground-source...

  5. HEAT TRANSFER FLUIDS

    E-Print Network [OSTI]

    Lenert, Andrej

    2012-01-01

    The choice of heat transfer fluids has significant effects on the performance, cost, and reliability of solar thermal systems. In this chapter, we evaluate existing heat transfer fluids such as oils and molten salts based ...

  6. Residential Variable-Capacity Heat Pumps Sized to Heating Loads

    SciTech Connect (OSTI)

    Munk, Jeffrey D.; Jackson, Roderick K.; Odukomaiya, Adewale; Gehl, Anthony C.

    2014-01-01

    Variable capacity heat pumps are an emerging technology offering significant energy savings potential and improved efficiency. With conventional single-speed systems, it is important to appropriately size heat pumps for the cooling load as over-sizing would result in cycling and insufficient latent capacity required for humidity control. These appropriately sized systems are often under-sized for the heating load and require inefficient supplemental electric resistance heat to meet the heating demand. Variable capacity heat pumps address these shortcomings by providing an opportunity to intentionally size systems for the dominant heating season load without adverse effects of cycling or insufficient dehumidification in the cooling season. This intentionally-sized system could result in significant energy savings in the heating season, as the need for inefficient supplemental electric resistance heat is drastically reduced. This is a continuation of a study evaluating the energy consumption of variable capacity heat pumps installed in two unoccupied research homes in Farragut, a suburb of Knoxville, Tennessee. In this particular study, space conditioning systems are intentionally sized for the heating season loads to provide an opportunity to understand and evaluate the impact this would have on electric resistance heat use and dehumidification. The results and conclusions drawn through this research are valid and specific for portions of the Southeastern and Midwestern United States falling in the mixed-humid climate zone. While other regions in the U.S. do not experience this type of climate, this work provides a basis for, and can help understand the implications of other climate zones on residential space conditioning energy consumption. The data presented here will provide a framework for fine tuning residential building EnergyPlus models that are being developed.

  7. Effects of system-bath entanglement on the performance of light-harvesting systems: A quantum heat engine perspective

    E-Print Network [OSTI]

    Dazhi Xu; Chen Wang; Yang Zhao; Jianshu Cao

    2015-08-19

    We explore energy transfer in a generic three-level system, which is coupled to three non-equilibrium baths. Built on the concept of quantum heat engine, our three-level model describes non-equilibrium quantum processes including light-harvesting energy transfer, nano-scale heat transfer, photo-induced isomerization, and photovoltaics in double quantum-dots. In the context of light-harvesting, the excitation energy is first pumped up by sunlight, then is transferred via two excited states which are coupled to a phonon bath, and finally decays to the ground state. The efficiency of this process is evaluated by steady state analysis via a polaron-transformed master equation; thus a wide range of the system-phonon coupling strength can be covered. We show that the coupling with the phonon bath not only modifies the steady state, resulting in population inversion, but also introduces a finite steady state coherence which optimizes the energy transfer flux and efficiency. In the strong coupling limit, the steady state coherence disappears and the efficiency approaches the heat engine limit given by Scovil and Schultz-Dubois in Phys. Rew. Lett. 2, 262 (1959).

  8. Heat pipe array heat exchanger

    DOE Patents [OSTI]

    Reimann, Robert C. (Lafayette, NY)

    1987-08-25

    A heat pipe arrangement for exchanging heat between two different temperature fluids. The heat pipe arrangement is in a ounterflow relationship to increase the efficiency of the coupling of the heat from a heat source to a heat sink.

  9. First university owned district heating system using biomass heat

    E-Print Network [OSTI]

    Northern British Columbia, University of

    Highlights · First university owned district heating system using biomass heat · Capacity: 15 MMBtu Main Campus District Heating Performance · Avoided: 3500 tonnes of CO2 · Particulate: less than 10 mg District Heating Goals To displace 85% of natural gas used for core campus heating. Fuel Bunker Sawmill

  10. Effects of system-bath entanglement on the performance of light-harvesting systems: A quantum heat engine perspective

    E-Print Network [OSTI]

    Xu, Dazhi; Zhao, Yang; Cao, Jianshu

    2015-01-01

    We explore energy transfer in a generic three-level system, which is coupled to three non-equilibrium baths. Built on the concept of quantum heat engine, our three-level model describes non-equilibrium quantum processes including light-harvesting energy transfer, nano-scale heat transfer, photo-induced isomerization, and photovoltaics in double quantum-dots. In the context of light-harvesting, the excitation energy is first pumped up by sunlight, then is transferred via two excited states which are coupled to a phonon bath, and finally decays to the ground state. The efficiency of this process is evaluated by steady state analysis via a polaron-transformed master equation; thus a wide range of the system-phonon coupling strength can be covered. We show that the coupling with the phonon bath not only modifies the steady state, resulting in population inversion, but also introduces a finite steady state coherence which optimizes the energy transfer flux and efficiency. In the strong coupling limit, the steady s...

  11. Passive solar space heating

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1980-01-01

    An overview of passive solar space heating is presented indicating trends in design, new developments, performance measures, analytical design aids, and monitored building results.

  12. Joule heating at high latitudes

    SciTech Connect (OSTI)

    Foster, J.C.; St.-Maurice, J.; Abreu, V.J.

    1983-06-01

    High latitude Joule heating has been calculated from simultaneous observations of the electric field magnitude and the Pedersen conductivity calculated from individual measurements of the ion drift velocity and particle precipitation observed over the lifetime of the AE-C satellite. The data were sorted by latitude, local time, hemisphere, season, and Kp index and separate averages of the electric field magnitude, Pedersen conductivity and Joule heating was prepared. Conductivities produced by an averaged seasonal solar illumination were included with those calculated from the particle precipitation. We found that high-latitude Joule heating occurs in a roughly oval pattern and consists of three distinct heating regions: the dayside cleft, the region of sunward convection at dawn and dusk, and the midnight sector. On the average, heating in the cleft and dawn-dusk regions contributes the largest heat input. There is no apparent difference between hemispheres for similar seasons. Hemisphere averaged Joule heating at equinox amounts to approximately 25 GW for Kp = 1 conditions, 85G GW for Kp = 4, and varies linearly as a function of Kp. The Joule heat input is 50% greater during the summer than during winter primarily due to the increased conductivity caused by solar production.

  13. Performance of the biose cascade-INEL manufactured solar home

    SciTech Connect (OSTI)

    Lau, A S; Liebelt, K H; Scofield, M P; Shinn, N R

    1980-01-01

    Two manufactured active solar homes using air collectors and rock storage were designed, bult and are being tested. The cooperative, DOE-funded project involves. Boise Cascade Corporation and the Idaho National Engineering Laboratory (INEL). The two primary goals of the project are to develop an active solar heating system that is cost-effective now, and to provide significant market penetration through the involvement of Boise Cascade, a major manufacturer of factory built houses. A brief discussion of the houses and solar systems is included, with more detailed discussion of the desktop-computer based data acquisition system and initial performance results. The 1979 cooling season data indicated a need for modifications to achieve adequate cooling system performance. Data from the heating season showed good agreement with calculations, especially the house heat loss coefficient. However, solar heating fractions were lower than predicted and an examination of the collector operating efficiency showed the collector losses to be approximately three times higher than predicted. Tests are underway to better understand the large collection losses. Comparison of the performance data and f-chart predictions shows significant differences, with predicted solar fractions being lower than actual. The solar domestic hot water preheating system performed reasonably well, with significant thermal losses noticed from the auxiliary hot water heater. Recommendations are made for the design of solar air-heating systems.

  14. Measured water heating performance of a vertical-bore water-to-water ground source heat pump (WW-GSHP) for domestic water heating over twelve months under simulated occupancy loads

    SciTech Connect (OSTI)

    Ally, Moonis Raza [ORNL; Munk, Jeffrey D [ORNL; Baxter, Van D [ORNL; Gehl, Anthony C [ORNL

    2014-01-01

    This paper presents monthly performance metrics of a 5.275 kW (1.5 ton) WW-GSHP providing 227 L day-1 domestic hot water at 49 C. Daily water use is simulated as stipulated in the Building America Research Benchmark Definition capturing the living habits of the average U.S household. The 94.5m vertical-bore ground loop is shared with a separate GSHP for space conditioning the 251m2 residential home. Data on entering water temperatures, energy extracted from the ground, delivered energy, compressor electricity use, COP, WW-GSHP run times, and the impact of fan and pump energy consumption on efficiency are presented for each month. Factors influencing performance metrics are highlighted.

  15. Seasonality in air transportation demand

    E-Print Network [OSTI]

    Reichard Megwinoff, H?tor Nicolas

    1988-01-01

    This thesis investigates the seasonality of demand in air transportation. It presents three methods for computing seasonal indices. One of these methods, the Periodic Average Method, is selected as the most appropriate for ...

  16. Innovative Porous Media Approach in Modeling Biofilm Applications, Human Eye and Nanofluid Based Heat Pipes

    E-Print Network [OSTI]

    Shafahi, Maryam

    2010-01-01

    silver nano-fluid on heat pipe thermal performance, Appliedof nanofluids on sintered heat pipe thermal performance,of nanofluid on flat heat pipe thermal performance, 24th

  17. Evaluation of five biocarriers as supports for immobilized bacteria: Comparative performance during high chemical loading, acid shocking, drying and heat shocking

    SciTech Connect (OSTI)

    Heitkamp, M.A.; Adams, W.J. (Monsanto Co., St. Louis, MO (United States). Environmental Sciences Center); Camel, V. (Ecole Superieure de Physique et Chimie Industrielle de Paris, (France))

    1993-06-01

    Immobilized bacteria technology (IBT) utilizes inert biocarriers to support high concentrations of chemical-degrading bacteria in reactors designed to provide optimal conditions for microbial activity. This study evaluated IBT performance inpacked bed reactors (PBRs) using a porous inorganic biocarrier (diatomaceous earth), nonporous biocarriers (glass beads), and organic biocarriers having carbon adsorption properties (granular activated carbon) with different porosity. Each reactor was challenged with high chemical loading, acid, dryness, and heat shock conditions. Benchtop PBSs inoculated with a p-nitrophenol (PNP)-degrading Pseudomonas sp. and fed a synthetic waste containing 100 to 1,300 mg/L of PNP showed removal of PNP from effluents within 24 h of start-up. Chemical loading studies showed maximum PNP removal rates of 6.45 to 7.35 kg/m[sup 3]/d for bacteria in PBRs containing diatomaceous earth beads, glass beads, and activated coconut carbon. A lower PNP removal rate of 1.47 kg/m[sup 3]/d was determined for the activated anthracite carbon, and this PBR responded more slowly to increases in chemical loading. The PBR containing bacteria immobilized on activated coconut carbon showed exceptional tolerance to acid shocking, drying, and heat shocking by maintaining PNP removal rates > 85% throughout the entire study. The other biocarriers showed nearly complete loss of PNP degradation during the perturbations, but all recovered high rates of PNP degradation (> 98% removal) within 48 h after an acid shock at pH2, within 8 d after an acid shock at pH 1.0, within 24 h after drying for 72 h, and within 48 h of heat shocking. The resiliency and high chemical removal efficiency demonstrated by immobilized bacteria in this study support the concept of using IBT for the biotreatment of industrial wastes..

  18. The seasonal cycle dependence of temperature fluctuations in the atmosphere 

    E-Print Network [OSTI]

    Tobin, Bridget Frances

    1994-01-01

    differences is the larger solar heating gradient in the winter. 40 years of monthly mean surface data and 25 years of monthly mean 700mb and 500mb data is averaged over the seasons. The spatial correlation of four northern hemisphere midlatitude test sites...

  19. Ocean Heat Transport , Overturning Circulations, and some fine-resolution ASOF dynamics

    E-Print Network [OSTI]

    , seasonal storage of heat in the mixed layer balances air/sea heat flux, so only a mixed layer ocean of Europe? (i.e., is air-sea heat flux dominated by seasonal storage in the mixed layer?) We have argued, it is thermally driven'. Why? -salt diffusion is essential to overturning circulation, -diffusion is molecular

  20. Collaborative National Program for the Development and Performance Testing of Distributed Power Technologies with Emphasis on Combined Heat and Power Applications

    SciTech Connect (OSTI)

    Soinski, Arthur; Hanson, Mark

    2006-06-28

    A current barrier to public acceptance of distributed generation (DG) and combined heat and power (CHP) technologies is the lack of credible and uniform information regarding system performance. Under a cooperative agreement, the Association of State Energy Research and Technology Transfer Institutions (ASERTTI) and the U.S. Department of Energy have developed four performance testing protocols to provide a uniform basis for comparison of systems. The protocols are for laboratory testing, field testing, long-term monitoring and case studies. They have been reviewed by a Stakeholder Advisory Committee made up of industry, public interest, end-user, and research community representatives. The types of systems covered include small turbines, reciprocating engines (including Stirling Cycle), and microturbines. The protocols are available for public use and the resulting data is publicly available in an online national database and two linked databases with further data from New York State. The protocols are interim pending comments and other feedback from users. Final protocols will be available in 2007. The interim protocols and the national database of operating systems can be accessed at www.dgdata.org. The project has entered Phase 2 in which protocols for fuel cell applications will be developed and the national and New York databases will continue to be maintained and populated.

  1. Miniaturized Air-to-Refrigerant Heat Exchangers

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    kW air-to-water and air-to- refrigerant heat exchangers Investigate conventional and additive manufacturing techniques Analyze system level performance of novel heat...

  2. Optimization of Heat Exchanger Cleaning 

    E-Print Network [OSTI]

    Siegell, J. H.

    1986-01-01

    EXCHANGER CLEANING Jeffrey H. Siegell Exxon Research and Engineering Company Florham Park, New Jersey ABSTRACT The performance of heat integration systems is quantified in terms of the amount of heat that is recovered. This decreases with time due... to increased fouling of the heat exchange surface. Using the "Total Fouling Related Expenses (TFRE)" approach, economic incentives for heat exchanger cleaning are evaluated using linear, exponential, and exponential finite decrease models of the heat...

  3. Thermoelectrics Partnership: High Performance Thermoelectric...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    High Performance Thermoelectric Waste Heat Recovery System Based on Zintl Phase Materials with Embedded Nanoparticles Thermoelectrics Partnership: High Performance Thermoelectric...

  4. Seasonal cycle dependence of temperature fluctuations in the atmosphere. Master's thesis

    SciTech Connect (OSTI)

    Tobin, B.F.

    1994-08-01

    The correlation statistics of meteorological fields have been of interest in weather forecasting for many years and are also of interest in climate studies. A better understanding of the seasonal variation of correlation statistics can be used to determine how the seasonal cycle of temperature fluctuations should be simulated in noise-forced energy balance models. It is shown that the length scale does have a seasonal dependence and will have to be handled through the seasonal modulation of other coefficients in noise-forced energy balance models. The temperature field variance and spatial correlation fluctuations exhibit seasonality with fluctuation amplitudes larger in the winter hemisphere and over land masses. Another factor contributing to seasonal differences is the larger solar heating gradient in the winter.

  5. Ground source heat storage and thermo-physical response of soft clay

    E-Print Network [OSTI]

    Saxe, Shoshanna Dawn

    2009-01-01

    Ground source heat storage can condition buildings with reduced consumption of fossil fuels, an important issue in modem building design. However, seasonal heat storage can cause soil temperature fluctuations and possibly ...

  6. No. 2 heating oil/propane program

    SciTech Connect (OSTI)

    McBrien, J.

    1991-06-01

    During the 1990/91 heating season, the Massachusetts Division of Energy Resources (DOER) participated in a joint data collection program between several state energy offices and the federal Department of Energy's (DOE) Energy Information Administration (EIA). The purpose of the program was to collect and monitor retail and wholesale heating oil and propane prices and inventories from October 1990 through March 1991. This final report begins with an overview of the unique events which had an impact on the reporting period. Next, the report summarizes the results from the residential heating oil and propane price surveys conducted by DOER over the 1990/91 heating season. The report also incorporates the wholesale heating oil and propane prices and inventories collected by the EIA and distributed to the states.

  7. THERMAL PERFORMANCE OF BUILDINGS AND BUILDING ENVELOPE SYSTEMS: AN ANNOTATED BIBLIOGRAPHY

    E-Print Network [OSTI]

    Carroll, William L.

    2011-01-01

    affecting wall heat transmission and tabulates calculatedprinciples for the heat transmission and thermal performanceexclusively on heat transmission and thermal performance.

  8. Energy performance analysis of prototype electrochromic windows

    SciTech Connect (OSTI)

    Sullivan, R.; Rubin, M.; Selkowitz, S.

    1996-12-01

    This paper presents the results of a study investigating the energy performance of three newly developed prototype electrochromic devices. The DOE-2.1 E energy simulation program was used to analyze the annual cooling, lighting, and total electric energy use and peak demand as a function of window type and size. The authors simulated a prototypical commercial office building module located in the cooling-dominated locations of Phoenix, AZ and Miami, FL. Heating energy use was also studied in the heating-dominated location of Madison, WI. Daylight illuminance was used to control electrochromic state-switching. Two types of window systems were analyzed; i.e., the outer pane electrochromic glazing was combined with either a conventional low-E or a spectrally selective inner pane. The properties of the electrochromic glazings are based on measured data of new prototypes developed as part of a cooperative DOE-industry program. The results show the largest difference in annual electric energy performance between the different window types occurs in Phoenix and is about 6.5 kWh/m{sup 2} floor area (0.60 kWh/ft{sup 2}) which can represent a cost of about $.52/m{sup 2} ($.05/ft{sup 2}) using electricity costing $.08/kWh. In heating-dominated locations, the electrochromic should be maintained in its bleached state during the heating season to take advantage of beneficial solar heat gain which would reduce the amount of required heating. This also means that the electrochromic window with the largest solar heat gain coefficient is best.

  9. Total Space Heating Water Heating Cook-

    Gasoline and Diesel Fuel Update (EIA)

    Released: September, 2008 Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing Other All Buildings* ... 1,602 1,397...

  10. Total Space Heating Water Heating Cook-

    Gasoline and Diesel Fuel Update (EIA)

    Energy Consumption Survey: Energy End-Use Consumption Tables Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing Other All...

  11. Total Space Heating Water Heating Cook-

    Gasoline and Diesel Fuel Update (EIA)

    Released: September, 2008 Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing Other All Buildings ... 2,037...

  12. Total Space Heating Water Heating Cook-

    Gasoline and Diesel Fuel Update (EIA)

    Released: September, 2008 Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing Other All Buildings* ... 1,870 1,276...

  13. Total Space Heating Water Heating Cook-

    Gasoline and Diesel Fuel Update (EIA)

    Tables Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing Other All Buildings ... 636 580 46 1 Q 114.0...

  14. Susanville District Heating District Heating Low Temperature...

    Open Energy Info (EERE)

    Susanville District Heating District Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Susanville District Heating District Heating Low Temperature...

  15. Thermal-barrier coatings: coating methods, performance, and heat-engine applications. July 1982-April 1989 (Citations from the EI Engineering Meetings data base). Report for July 1982-April 1989

    SciTech Connect (OSTI)

    Not Available

    1989-04-01

    This bibliography contains citations from conference proceedings concerning coating methods, performance evaluations, and applications of thermal-barrier coatings as protective coatings for heat-engine components against high temperature corrosions and chemical erosions. The developments of thermal barrier-coating techniques for high performance and reliable gas turbines, diesel engines, jet engines, and internal combustion engines are presented. Topics include plasma-sprayed-coating methods, yttria-stabilized zirconia coatings, coating-life models, coating failure and durability, thermal shock and cycling, and acoustic-emission analysis of coatings. (Contains 101 citations fully indexed and including a title list.)

  16. Molecular heat pump

    E-Print Network [OSTI]

    Dvira Segal; Abraham Nitzan

    2005-10-11

    We propose a novel molecular device that pumps heat against a thermal gradient. The system consists of a molecular element connecting two thermal reservoirs that are characterized by different spectral properties. The pumping action is achieved by applying an external force that periodically modulates molecular levels. This modulation affects periodic oscillations of the internal temperature of the molecule and the strength of its coupling to each reservoir resulting in a net heat flow in the desired direction. The heat flow is examined in the slow and fast modulation limits and for different modulation waveforms, thus making it possible to optimize the device performance.

  17. Status report on survey of alternative heat pumping technologies

    SciTech Connect (OSTI)

    Fischer, S.

    1998-07-01

    The Department of Energy is studying alternative heat pumping technologies to identify possible cost effective alternatives to electric driven vapor compression heat pumps, air conditioners, and chillers that could help reduce CO{sub 2} emissions. Over thirty different technologies are being considered including: engine driven systems, fuel cell powered systems, and alternative cycles. Results presented include theoretical efficiencies for all systems as well as measured performance of some commercial, prototype, or experimental systems. Theoretical efficiencies show that the alternative electric-driven technologies would have HSPFs between 4 and 8 Btu/Wh (1.2 to 2.3 W/W) and SEERs between 3 and 9.5 Btu/Wh (0.9 and 2.8 W/W). Gas-fired heat pump technologies have theoretical seasonal heating gCOPs from 1.1 to 1.7 and cooling gCOPs from 0.95 to 1.6 (a SEER 12 Btu/Wh electric air conditioner has a primary energy efficiency of approximately 1.4 W/W).

  18. An experimental study on the effect of ultrasonication on viscosity and heat transfer performance of aqueous suspensions of multi-walled carbon nanotubes 

    E-Print Network [OSTI]

    Garg, Paritosh

    2009-05-15

    thermal 6 conductivity and convective heat transfer as compared to the base fluid [1-5]. These nanoparticles could be either metal oxides of copper, copper oxide, aluminium, alumina, titania, or they could be non-metals like carbon. In this work, we...

  19. NREL GHP [Geothermal Heat Pump] Showcase: GHP Installation and Intensive in situ and Performance Monitoring at NREL's Solar Radiation and Research Laboratory; Preprint

    SciTech Connect (OSTI)

    Anderson, E. R.

    2010-07-01

    This document provides an overview of the geothermal heat pump (GHP) showcase at NREL and how it will help the SRRL site move forward with the goal of being a model of sustainability within the NREL campus, providing an effective demonstration of GHP systems and needed space conditioning for laboratory expansion.

  20. Heat and mass transfer considerations in advanced heat pump systems

    SciTech Connect (OSTI)

    Panchal, C.B.; Bell, K.J.

    1992-08-01

    Advanced heat-pump cycles are being investigated for various applications. However, the working media and associated thermal design aspects require new concepts for maintaining high thermal effectiveness and phase equilibrium for achieving maximum possible thermodynamic advantages. In the present study, the heat- and mass-transfer processes in two heat-pump systems -- those based on absorption processes, and those using refrigerant mixtures -- are analyzed. The major technical barriers for achieving the ideal performance predicted by thermodynamic analysis are identified. The analysis provides general guidelines for the development of heat- and mass-transfer equipment for advanced heat-pump systems.

  1. Heat and mass transfer considerations in advanced heat pump systems

    SciTech Connect (OSTI)

    Panchal, C.B.; Bell, K.J.

    1992-01-01

    Advanced heat-pump cycles are being investigated for various applications. However, the working media and associated thermal design aspects require new concepts for maintaining high thermal effectiveness and phase equilibrium for achieving maximum possible thermodynamic advantages. In the present study, the heat- and mass-transfer processes in two heat-pump systems -- those based on absorption processes, and those using refrigerant mixtures -- are analyzed. The major technical barriers for achieving the ideal performance predicted by thermodynamic analysis are identified. The analysis provides general guidelines for the development of heat- and mass-transfer equipment for advanced heat-pump systems.

  2. Patterns of water and heat flux across a biome gradient from tropical forest to savanna in Brazil

    E-Print Network [OSTI]

    2009-01-01

    of Mato Grosso, Brasil, Water Resour. Res. , 38(6), 1094,2009 Patterns of water and heat flux across a biome gradientFigueira (2004), Seasonality of water and heat fluxes over a

  3. Incorporating Seasonality into Search Suggestions Derived from Intranet Query Logs

    E-Print Network [OSTI]

    Kruschwitz, Udo

    Incorporating Seasonality into Search Suggestions Derived from Intranet Query Logs Stephen Dignum performed on query logs collected for major Web search engines, query log analysis to enhance search search engine can be enhanced by adapting the search system to real users' search behaviour through

  4. Solar water heating: FEMP fact sheet

    SciTech Connect (OSTI)

    Clyne, R.

    1999-09-30

    Using the sun to heat domestic water makes sense in almost any climate. Solar water heaters typically provide 40 to 80{percent} of a building's annual water-heating needs. A solar water-heating system's performance depends primarily on the outdoor temperature, the temperature to which the water is heated, and the amount of sunlight striking the collector.

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

    E-Print Network [OSTI]

    Hong, Tainzhen

    2010-01-01

    Performance of ground source heat pump system in a near-zerosimulation tool for ground- source heat pump system designflow systems and ground source heat pump systems Abstract

  6. Solar industrial process heat

    SciTech Connect (OSTI)

    Lumsdaine, E.

    1981-04-01

    The aim of the assessment reported is to candidly examine the contribution that solar industrial process heat (SIPH) is realistically able to make in the near and long-term energy futures of the United States. The performance history of government and privately funded SIPH demonstration programs, 15 of which are briefly summarized, and the present status of SIPH technology are discussed. The technical and performance characteristics of solar industrial process heat plants and equipment are reviewed, as well as evaluating how the operating experience of over a dozen SIPH demonstration projects is influencing institutional acceptance and economoc projections. Implications for domestic energy policy and international implications are briefly discussed. (LEW)

  7. Phase Change Heat Transfer Device for Process Heat Applications

    SciTech Connect (OSTI)

    Piyush Sabharwall; Mike Patterson; Vivek Utgikar; Fred Gunnerson

    2010-10-01

    The next generation nuclear plant (NGNP) will most likely produce electricity and process heat, with both being considered for hydrogen production. To capture nuclear process heat, and transport it to a distant industrial facility requires a high temperature system of heat exchangers, pumps and/or compressors. The heat transfer system is particularly challenging not only due to the elevated temperatures (up to approx.1300 K) and industrial scale power transport (=50MW), but also due to a potentially large separation distance between the nuclear and industrial plants (100+m) dictated by safety and licensing mandates. The work reported here is the preliminary analysis of two-phase thermosyphon heat transfer performance with alkali metals. A thermosyphon is a thermal device for transporting heat from one point to another with quite extraordinary properties. In contrast to single-phased forced convective heat transfer via ‘pumping a fluid’, a thermosyphon (also called a wickless heat pipe) transfers heat through the vaporization/condensing process. The condensate is further returned to the hot source by gravity, i.e., without any requirement of pumps or compressors. With this mode of heat transfer, the thermosyphon has the capability to transport heat at high rates over appreciable distances, virtually isothermally and without any requirement for external pumping devices. Two-phase heat transfer by a thermosyphon has the advantage of high enthalpy transport that includes the sensible heat of the liquid, the latent heat of vaporization, and vapor superheat. In contrast, single-phase forced convection transports only the sensible heat of the fluid. Additionally, vapor-phase velocities within a thermosyphon are much greater than single-phase liquid velocities within a forced convective loop. Thermosyphon performance can be limited by the sonic limit (choking) of vapor flow and/or by condensate entrainment. Proper thermosyphon requires analysis of both.

  8. Waste Heat Reduction and Recovery for Improving Furnace Efficiency...

    Broader source: Energy.gov (indexed) [DOE]

    Waste Heat Reduction and Recovery for Improving Furnace Efficiency, Productivity and Emissions Performance: A BestPractices Process Heating Technical Brief (November 2004) More...

  9. HEAT STORAGE AND ADVECTION IN THE NORTH PACIFIC OCEAN

    E-Print Network [OSTI]

    Luther, Douglas S.

    HEAT STORAGE AND ADVECTION IN THE NORTH PACIFIC OCEAN A DISSERTATION SUBMITTED TO THE GRADUATE maintaining the seasonal heat storage in the 0 to 250 meter surface layer of the North Pacific Ocean. Approximately 140,000 bathy- thermograph observations taken in the Pacific Ocean from 10° South latitude to 70

  10. Heat Pump Clothes Dryer | Department of Energy

    Broader source: Energy.gov (indexed) [DOE]

    Schematics of a heat pump clothes dryer
    Credit: Oak Ridge National Lab Schematics of a heat pump clothes dryer Credit: Oak Ridge National Lab Lead Performer: Oak Ridge...

  11. Air-to-Water Heat Pumps With Radiant Delivery in Low-Load Homes

    SciTech Connect (OSTI)

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

    2013-12-01

    Space conditioning represents nearly 50% of average residential household energy consumption, highlighting the need to identify alternative cost-effective, energy-efficient cooling and heating strategies. As homes are better built, there is an increasing need for strategies that are particularly well suited for high performance, low load homes. ARBI researchers worked with two test homes in hot-dry climates to evaluate the in-situ performance of air-to-water heat pump (AWHP) systems, an energy efficient space conditioning solution designed to cost-effectively provide comfort in homes with efficient, safe, and durable operation. Two monitoring projects of test houses in hot-dry climates were initiated in 2010 to test this system. Both systems were fully instrumented and have been monitored over one year to capture complete performance data over the cooling and heating seasons. Results are used to quantify energy savings, cost-effectiveness, and system performance using different operating modes and strategies. A calibrated TRNSYS model was developed and used to evaluate performance in various climate regions. This strategy is most effective in tight, insulated homes with high levels of thermal mass (i.e. exposed slab floors).

  12. Air-to-Water Heat Pumps With Radiant Delivery in Low-Load Homes

    SciTech Connect (OSTI)

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

    2013-12-01

    Space conditioning represents nearly 50% of average residential household energy consumption, highlighting the need to identify alternative cost-effective, energy-efficient cooling and heating strategies. As homes are better built, there is an increasing need for strategies that are particularly well suited for high performance, low load homes. ARBI researchers worked with two test homes in hot-dry climates to evaluate the in-situ performance of air-to-water heat pump systems, an energy efficient space conditioning solution designed to cost-effectively provide comfort in homes with efficient, safe, and durable operation. Two monitoring projects of test houses in hot-dry climates were initiated in 2010 to test this system. Both systems were fully instrumented and have been monitored over one year to capture complete performance data over the cooling and heating seasons. Results are used to quantify energy savings, cost-effectiveness, and system performance using different operating modes and strategies. A calibrated TRNSYS model was developed and used to evaluate performance in various climate regions. This strategy is most effective in tight, insulated homes with high levels of thermal mass (i.e. exposed slab floors).

  13. Heat collector

    DOE Patents [OSTI]

    Merrigan, M.A.

    1981-06-29

    A heat collector and method suitable for efficiently and cheaply collecting solar and other thermal energy are provided. The collector employs a heat pipe in a gravity-assist mode and is not evacuated. The collector has many advantages, some of which include ease of assembly, reduced structural stresses on the heat pipe enclosure, and a low total materials cost requirement. Natural convective forces drive the collector, which after startup operates entirely passively due in part to differences in molecular weights of gaseous components within the collector.

  14. Heat collector

    DOE Patents [OSTI]

    Merrigan, Michael A. (Santa Cruz, NM)

    1984-01-01

    A heat collector and method suitable for efficiently and cheaply collecting solar and other thermal energy are provided. The collector employs a heat pipe in a gravity-assist mode and is not evacuated. The collector has many advantages, some of which include ease of assembly, reduced structural stresses on the heat pipe enclosure, and a low total materials cost requirement. Natural convective forces drive the collector, which after startup operates entirely passively due in part to differences in molecular weights of gaseous components within the collector.

  15. Citrus limonoids: seasonal changes and their potential in glutathione S-transferase induction 

    E-Print Network [OSTI]

    Li, Jiaxing

    2002-01-01

    Seasonal changes of citrus limonids in 'Rio Red' grapefruit were investigated using reverse phase high performance liquid chromatography (HPLC). Several citrus limonoids, limonoid mixtures and a flavonone were evaluated for their ability to induce...

  16. Corrosive resistant heat exchanger

    DOE Patents [OSTI]

    Richlen, Scott L. (Annandale, VA)

    1989-01-01

    A corrosive and errosive resistant heat exchanger which recovers heat from a contaminated heat stream. The heat exchanger utilizes a boundary layer of innocuous gas, which is continuously replenished, to protect the heat exchanger surface from the hot contaminated gas. The innocuous gas is conveyed through ducts or perforations in the heat exchanger wall. Heat from the heat stream is transferred by radiation to the heat exchanger wall. Heat is removed from the outer heat exchanger wall by a heat recovery medium.

  17. Design, development and testing of a solar-powered multi-family residential size prototype turbocompressor heat pump

    SciTech Connect (OSTI)

    None

    1981-03-01

    A program described to design, fabricate, and conduct preliminary testing of a prototype solar-powered Rankine cycle turbocompressor heat pump module for a multi-family residential building is presented. A solar system designed to use the turbocompressor heat pump module including all of the subsystems required and the various system operating modes is described in Section I. Section II includes the preliminary design analyses conducted to select the heat pump module components and operating features, working fluid, configuration, size and performance goals, and estimated performance levels in the cooling and heating modes. Section III provides a detailed description of the other subsystems and components required for a complete solar installation. Using realistic performance and cost characteristics for all subsystems, the seasonal performance of the UTC heat pump is described in various US locations. In addition, the estimated energy savings and an assessment of the economic viability of the solar system is presented in Section III. The detailed design of the heat pump module and the arrangement of components and controls selected to conduct the laboratory performance tests are described in Section IV. Section V provides a description of the special laboratory test facility, including the subsystems to simulate the collectors and storage tanks for building load and ambient conditions and the instrumentation, monitoring, and data acquisition equipment. The test results and sample computer analyses and comparisons with predicted performance levels are presented in Section VI. Various appendices provide supplementary and background information concerning working fluid selection (A), configuration selection (B), capacity control concepts (C), building models (D), computer programs used to determine component and system performance and total system economics (E), and weather data (F).

  18. Seasonal thermal energy storage program. Progress report, January 1980-December 1980

    SciTech Connect (OSTI)

    Minor, J.E.

    1981-05-01

    The objectives of the Seasonal Thermal Energy Storage (STES) Program is to demonstrate the economic storage and retrieval of energy on a seasonal basis, using heat or cold available from waste sources or other sources during a surplus period to reduce peak period demand, reduce electric utilities peaking problems, and contribute to the establishment of favorable economics for district heating and cooling systems for commercialization of the technology. Aquifers, ponds, earth, and lakes have potential for seasonal storage. The initial thrust of the STES Program is toward utilization of ground-water systems (aquifers) for thermal energy storage. Program plans for meeting these objectives, the development of demonstration programs, and progress in assessing the technical, economic, legal, and environmental impacts of thermal energy storage are described. (LCL)

  19. Exchange of groundwater and surfacewater mediated by permafrost response to seasonal and long term air

    E-Print Network [OSTI]

    McKenzie, Jeffrey M.

    Exchange of groundwater and surfacewater mediated by permafrost response to seasonal and long term impact hydrologic cycle processes by promoting or impeding groundwater and surface water exchange. Under between groundwater and surface water. A coupled heat transport and groundwater flow model, SUTRA

  20. Heat Transfer Research, 2010, Vol. 41, No. 6 Turbine Aero-Heat Transfer Studies

    E-Print Network [OSTI]

    Camci, Cengiz

    AU TH O R PR O O F Heat Transfer Research, 2010, Vol. 41, No. 6 Turbine Aero-Heat Transfer Studies in Rotating Research Facilities CENGIZ CAMCI Turbomachinery Aero-Heat Transfer Laboratory, Department The present paper deals with the experimental aero-heat transfer studies performed in rotating turbine

  1. Active heat transfer enhancement in integrated fan heat sinks

    E-Print Network [OSTI]

    Staats, Wayne Lawrence

    2012-01-01

    Modern computer processors require significant cooling to achieve their full performance. The "efficiency" of heat sinks is also becoming more important: cooling of electronics consumes 1% of worldwide electricity use by ...

  2. Intrinsically irreversible heat engine

    DOE Patents [OSTI]

    Wheatley, J.C.; Swift, G.W.; Migliori, A.

    1984-12-25

    A class of heat engines based on an intrinsically irreversible heat transfer process is disclosed. In a typical embodiment the engine comprises a compressible fluid that is cyclically compressed and expanded while at the same time being driven in reciprocal motion by a positive displacement drive means. A second thermodynamic medium is maintained in imperfect thermal contact with the fluid and bears a broken thermodynamic symmetry with respect to the fluid. The second thermodynamic medium is a structure adapted to have a low fluid flow impedance with respect to the compressible fluid, and which is further adapted to be in only moderate thermal contact with the fluid. In operation, thermal energy is pumped along the second medium due to a phase lag between the cyclical heating and cooling of the fluid and the resulting heat conduction between the fluid and the medium. In a preferred embodiment the engine comprises an acoustical drive and a housing containing a gas which is driven at a resonant frequency so as to be maintained in a standing wave. Operation of the engine at acoustic frequencies improves the power density and coefficient of performance. The second thermodynamic medium can be coupled to suitable heat exchangers to utilize the engine as a simple refrigeration device having no mechanical moving parts. Alternatively, the engine is reversible in function so as to be utilizable as a prime mover by coupling it to suitable sources and sinks of heat. 11 figs.

  3. Intrinsically irreversible heat engine

    DOE Patents [OSTI]

    Wheatley, J.C.; Swift, G.W.; Migliori, A.

    1984-01-01

    A class of heat engines based on an intrinsically irreversible heat transfer process is disclosed. In a typical embodiment the engine comprises a compressible fluid that is cyclically compressed and expanded while at the same time being driven in reciprocal motion by a positive displacement drive means. A second thermodynamic medium is maintained in imperfect thermal contact with the fluid and bears a broken thermodynamic symmetry with respect to the fluid. The second thermodynamic medium is a structure adapted to have a low fluid flow impedance with respect to the compressible fluid, and which is further adapted to be in only moderate thermal contact with the fluid. In operation, thermal energy is pumped along the second medium due to a phase lag between the cyclical heating and cooling of the fluid and the resulting heat conduction between the fluid and the medium. In a preferred embodiment the engine comprises an acoustical drive and a housing containing a gas which is driven at a resonant frequency so as to be maintained in a standing wave. Operation of the engine at acoustic frequencies improves the power density and coefficient of performance. The second thermodynamic medium can be coupled to suitable heat exchangers to utilize the engine as a simple refrigeration device having no mechanical moving parts. Alternatively, the engine is reversible in function so as to be utilizable as a prime mover by coupling it to suitable sources and sinks of heat.

  4. Intrinsically irreversible heat engine

    DOE Patents [OSTI]

    Wheatley, John C. (Los Alamos, NM); Swift, Gregory W. (Los Alamos, NM); Migliori, Albert (Santa Fe, NM)

    1984-01-01

    A class of heat engines based on an intrinsically irreversible heat transfer process is disclosed. In a typical embodiment the engine comprises a compressible fluid that is cyclically compressed and expanded while at the same time being driven in reciprocal motion by a positive displacement drive means. A second thermodynamic medium is maintained in imperfect thermal contact with the fluid and bears a broken thermodynamic symmetry with respect to the fluid. the second thermodynamic medium is a structure adapted to have a low fluid flow impedance with respect to the compressible fluid, and which is further adapted to be in only moderate thermal contact with the fluid. In operation, thermal energy is pumped along the second medium due to a phase lag between the cyclical heating and cooling of the fluid and the resulting heat conduction between the fluid and the medium. In a preferred embodiment the engine comprises an acoustical drive and a housing containing a gas which is driven at a resonant frequency so as to be maintained in a standing wave. Operation of the engine at acoustic frequencies improves the power density and coefficient of performance. The second thermodynamic medium can be coupled to suitable heat exchangers to utilize the engine as a simple refrigeration device having no mechanical moving parts. Alternatively, the engine is reversible in function so as to be utilizable as a prime mover by coupling it to suitable sources and sinks of heat.

  5. Strategies for Aligning Program Demand with Contractor's Seasonal...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Aligning Program Demand with Contractor's Seasonal Fluctuations Strategies for Aligning Program Demand with Contractor's Seasonal Fluctuations Better Buildings Neighborhood Program...

  6. Heat Recovery Steam Generator Simulation 

    E-Print Network [OSTI]

    Ganapathy, V.

    1993-01-01

    The paper discusses the applications of Heat Recovery Steam Generator Simulation. Consultants, plant engineers and plant developers can evaluate the steam side performance of HRSGs and arrive at the optimum system which matches the needs...

  7. Seasonal Tips | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCED MANUFACTURINGEnergy BillsNo.Hydrogen4 » Search results SearchMiddle SchoolDownloadSeasonal Tips

  8. ABSORPTION HEAT PUMP IN THE DISTRICT HEATING

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    #12;ABSORPTION HEAT PUMP IN THE DISTRICT HEATING PLANT Dr.sc.ing. Agnese Lickrastina M.Sc. Normunds European Heat Pump Summit 2013, Nuremberg, 15-16.10.2013 · Riga District Heating company · Operation of the DH plant Imanta · Selection of the heat pump/chiller · Operation of the heat pump/chiller · Summary

  9. Development of a Transient Heat and Mass Transfer Model of Residential Attics to Predict Energy Savings Produced by the Use of Radiant Barriers 

    E-Print Network [OSTI]

    Medina, M. A.

    1992-01-01

    : different attic insulation levels, various attic airflow rates, cooling and heating seasons, and different radiant barrier orientations. The model predicted ceiling heat flows within 10% for most cases. The model was used to run simulations and parametric...

  10. Optimized design of a heat exchanger for an air-to-water reversible heat pump working with propane (R290)

    E-Print Network [OSTI]

    Fernández de Córdoba, Pedro

    Optimized design of a heat exchanger for an air-to-water reversible heat pump working with propane-to-water reversible heat pump unit was carried out using two different fin-and-tube heat exchanger ``coil'' designs concepts. The performance of the heat pump was evaluated for each coil design at different superheat

  11. Minimal universal quantum heat machine

    E-Print Network [OSTI]

    David Gelbwaser-Klimovsky; Robert Alicki; Gershon Kurizki

    2013-01-29

    In traditional thermodynamics the Carnot cycle yields the ideal performance bound of heat engines and refrigerators. We propose and analyze a minimal model of a heat machine that can play a similar role in quantum regimes. The minimal model consists of a single two-level system with periodically modulated energy splitting that is permanently, weakly, coupled to two spectrally-separated heat baths at different temperatures. The equation of motion allows to compute the stationary power and heat currents in the machine consistently with the second-law of thermodynamics. This dual-purpose machine can act as either an engine or a refrigerator (heat pump) depending on the modulation rate. In both modes of operation the maximal Carnot efficiency is reached at zero power. We study the conditions for finite-time optimal performance for several variants of the model. Possible realizations of the model are discussed.

  12. Effects of the seasonal cycle on superrotation in planetary atmospheres

    SciTech Connect (OSTI)

    Mitchell, Jonathan L. [Department of Earth and Space Sciences, University of California Los Angeles, Los Angeles, CA 90095 (United States); Vallis, Geoffrey K. [College of Engineering, Mathematics and Physical Science, Exeter University, Exeter (United Kingdom); Potter, Samuel F. [Atmospheric and Oceanic Sciences Program, Princeton University, NJ 08544 (United States)

    2014-05-20

    The dynamics of dry atmospheric general circulation model simulations forced by seasonally varying Newtonian relaxation are explored over a wide range of two control parameters and are compared with the large-scale circulation of Earth, Mars, and Titan in their relevant parameter regimes. Of the parameters that govern the behavior of the system, the thermal Rossby number (Ro) has previously been found to be important in governing the spontaneous transition from an Earth-like climatology of winds to a superrotating one with prograde equatorial winds, in the absence of a seasonal cycle. This case is somewhat unrealistic as it applies only if the planet has zero obliquity or if surface thermal inertia is very large. While Venus has nearly vanishing obliquity, Earth, Mars, and Titan (Saturn) all have obliquities of ?25° and varying degrees of seasonality due to their differing thermal inertias and orbital periods. Motivated by this, we introduce a time-dependent Newtonian cooling to drive a seasonal cycle using idealized model forcing, and we define a second control parameter that mimics non-dimensional thermal inertia of planetary surfaces. We then perform and analyze simulations across the parameter range bracketed by Earth-like and Titan-like regimes, assess the impact on the spontaneous transition to superrotation, and compare Earth, Mars, and Titan to the model simulations in the relevant parameter regime. We find that a large seasonal cycle (small thermal inertia) prevents model atmospheres with large thermal Rossby numbers from developing superrotation by the influences of (1) cross-equatorial momentum advection by the Hadley circulation and (2) hemispherically asymmetric zonal-mean zonal winds that suppress instabilities leading to equatorial momentum convergence. We also demonstrate that baroclinic instabilities must be sufficiently weak to allow superrotation to develop. In the relevant parameter regimes, our seasonal model simulations compare favorably to large-scale, seasonal phenomena observed on Earth and Mars. In the Titan-like regime the seasonal cycle in our model acts to prevent superrotation from developing, and it is necessary to increase the value of a third parameter—the atmospheric Newtonian cooling time—to achieve a superrotating climatology.

  13. Electrochemical heat engine

    DOE Patents [OSTI]

    Elliott, Guy R. B. (Los Alamos, NM); Holley, Charles E. (Alcalde, NM); Houseman, Barton L. (Cockeysville, MD); Sibbitt, Jr., Wilmer L. (Albuquerque, NM)

    1978-01-01

    Electrochemical heat engines produce electrochemical work, and mechanical motion is limited to valve and switching actions as the heat-to-work cycles are performed. The electrochemical cells of said heat engines use molten or solid electrolytes at high temperatures. One or more reactions in the cycle will generate a gas at high temperature which can be condensed at a lower temperature with later return of the condensate to electrochemical cells. Sodium, potassium, and cesium are used as the working gases for high temperature cells (above 600 K) with halogen gases or volatile halides being used at lower temperature. Carbonates and halides are used as molten electrolytes and the solid electrolyte in these melts can also be used as a cell separator.

  14. Seasonal variations in the subauroral electron temperature enhancement

    SciTech Connect (OSTI)

    Fok, M.C.; Kozyra, J.U.; Warren, M.F. (Univ. of Michigan, Ann Arbor (USA)); Brace, L.H. (NASA Goddard Space Flight Center, Greenbelt, MD (USA))

    1991-06-01

    The subauroral nightside electron temperature peak is one of the phenomena showing the response of the subauroral ionosphere to the influx of magnetic storm energy in the vicinity of the plasmapause. A statistical study of the seasonal variations of the subauroral electron temperature enhancement was undertaken using data from the Langmuir probe experiment on the DE 2 satellite throughout most of the mission (1981-1982). In the winter hemisphere the nighttime background electron temperature is the highest and the magnitude of the peak T{sub e} responds most weakly to the geomagnetic activity. This behavior can be explained by seasonal trends in the nighttime downward heat flux due to conjugate photoelectrons. Moreover, model results indicate that a factor of {approximately}3 increase in heat inflow during equinox relative to solstice is required to raise the electron temperature to a given level. This is a consequence of the higher electron densities at the T{sub e} peak near equinox. The T{sub e} peak occurs on field lines which thread the outer plasmasphere in the vicinity of the plasmapause and thus can be used as a tracer of the plasmapause position. Correlating the position of the T{sub e} peak with K{sub p} (the highest value of 3-hour K{sub p} in the preceding 12 hours) indicates a trend toward a more expanded quiet time plasmasphere and one which is more easily compressed by magnetic storms at equinox than during the solstice period.

  15. Heat extraction from salinity-gradient solar ponds using heat pipe heat exchangers

    SciTech Connect (OSTI)

    Tundee, Sura; Terdtoon, Pradit; Sakulchangsatjatai, Phrut; Singh, Randeep; Akbarzadeh, Aliakbar

    2010-09-15

    This paper presents the results of experimental and theoretical analysis on the heat extraction process from solar pond by using the heat pipe heat exchanger. In order to conduct research work, a small scale experimental solar pond with an area of 7.0 m{sup 2} and a depth of 1.5 m was built at Khon Kaen in North-Eastern Thailand (16 27'N102 E). Heat was successfully extracted from the lower convective zone (LCZ) of the solar pond by using a heat pipe heat exchanger made from 60 copper tubes with 21 mm inside diameter and 22 mm outside diameter. The length of the evaporator and condenser section was 800 mm and 200 mm respectively. R134a was used as the heat transfer fluid in the experiment. The theoretical model was formulated for the solar pond heat extraction on the basis of the energy conservation equations and by using the solar radiation data for the above location. Numerical methods were used to solve the modeling equations. In the analysis, the performance of heat exchanger is investigated by varying the velocity of inlet air used to extract heat from the condenser end of the heat pipe heat exchanger (HPHE). Air velocity was found to have a significant influence on the effectiveness of heat pipe heat exchanger. In the present investigation, there was an increase in effectiveness by 43% as the air velocity was decreased from 5 m/s to 1 m/s. The results obtained from the theoretical model showed good agreement with the experimental data. (author)

  16. The effect of nonuniform axial heat flux distribution on the critical heat flux

    E-Print Network [OSTI]

    Todreas, Neil E.

    1965-01-01

    A systematic experimental and analytic investigation of the effect of nonuniform axial heat flux distribution on critical heat rilux was performed with water in the quality condition. Utilizing a model which ascribes the ...

  17. An Analysis of the Use of Fluidized-Bed Heat Exchangers for Heat Recovery 

    E-Print Network [OSTI]

    Vogel, G. J.; Grogan, P. J.

    1980-01-01

    The principles of fluidized-bed operation and the factors affecting the performance of a fluidized-bed waste heat boiler (FBWHB) are discussed in detail. Factors included in the discussion are bed temperature and pressure, heat transfer coefficient...

  18. Number 2 heating oil/propane program. Final report, 1991/92

    SciTech Connect (OSTI)

    McBrien, J.

    1992-06-01

    During the 1991--92 heating season, the Massachusetts Division of Energy Resources (DOER) participated in a joint data collection program between several state energy offices and the federal Department of Energy`s (DOE) Energy Information Administration (EIA). The purpose of the program was to collect and monitor retail and wholesale heating oil and propane prices and inventories from October, 1991 through March, 1992. This final report begins with an overview of the unique events which had an impact on the reporting period. Next, the report summarizes the results from the residential heating oil and propane price surveys conducted by DOER over the 1991--1992 heating season. The report also incorporates the wholesale heating oil and propane prices and inventories collected by the EIA and distributed to the states. Finally, the report outlines DOER`s use of the data and responses to the events which unfolded during the 1991--1992 heating season.

  19. Preliminary Retro-Commissioning Study on Optimal Operation for the Heat Source System of a District Heating Cooling Plant 

    E-Print Network [OSTI]

    Shingu, H.; Yoshida, H.; Wang, F.; Ono, E.

    2008-01-01

    In order to improve the energy performance of a district heating and cooling (DHC) plant, the expected performance of the plant is studied using simulations based on mathematical models. A complete heat source system model, equipped with an embedded...

  20. Effect of combined nanoparticle and polymeric dispersions on critical heat flux, nucleate boiling heat transfer coefficient, and coating adhesion

    E-Print Network [OSTI]

    Edwards, Bronwyn K

    2009-01-01

    An experimental study was performed to determine thermal performance and adhesion effects of a combined nanoparticle and polymeric dispersion coating. The critical heat flux (CHF) values and nucleate boiling heat transfer ...

  1. Impact of Ducting on Heat Pump Water Heater Space Conditioning Energy Use and Comfort

    SciTech Connect (OSTI)

    Widder, Sarah H.; Petersen, Joseph M.; Parker, Graham B.; Baechler, Michael C.

    2014-07-21

    Increasing penetration of heat pump water heaters (HPWHs) in the residential sector will offer an important opportunity for energy savings, with a theoretical energy savings of up to 63% per water heater and up to 11% of residential energy use (EIA 2009). However, significant barriers must be overcome before this technology will reach widespread adoption in the Pacific Northwest region and nationwide. One significant barrier noted by the Northwest Energy Efficiency Alliance (NEEA) is the possible interaction with the homes’ space conditioning system for units installed in conditioned spaces. Such complex interactions may decrease the magnitude of whole-house savings available from HPWH installed in the conditioned space in cold climates and could lead to comfort concerns (Larson et al. 2011; Kresta 2012). Modeling studies indicate that the installation location of HPWHs can significantly impact their performance and the resultant whole-house energy savings (Larson et al. 2012; Maguire et al. 2013). However, field data are not currently available to validate these results. This field evaluation of two GE GeoSpring HPWHs in the PNNL Lab Homes is designed to measure the performance and impact on the Lab Home HVAC system of a GE GeoSpring HPWH configured with exhaust ducting compared to an unducted GeoSpring HPWH during heating and cooling season periods; and measure the performance and impact on the Lab Home HVAC system of the GeoSpring HPWH with both supply and exhaust air ducting as compared to an unducted GeoSpring HPWH during heating and cooling season periods. Important metrics evaluated in these experiments include water heater energy use, HVAC energy use, whole house energy use, interior temperatures (as a proxy for thermal comfort), and cost impacts. This technical report presents results from the PNNL Lab Homes experiment.

  2. Solar Domestic Water Heating: a Roof-Integrated Evaluation

    SciTech Connect (OSTI)

    2009-09-03

    This fact sheet describes an evaluation of the performance of a roof-integrated solar water heating system.

  3. Effects of exercise or oocyte heat shock on embryo development and gene expression in the horse 

    E-Print Network [OSTI]

    Mortensen, Christopher John

    2009-05-15

    Horse owners commonly maintain their broodmares in training and competition during the breeding season. The effect this has on mare reproductive efficiency has received limited attention. Heat stress has shown to be ...

  4. Residential Slab-On-Grade Heat Transfer in Hot Humid Climates 

    E-Print Network [OSTI]

    Clark, E.; Ascolese, M.; Collins, W.

    1989-01-01

    Heat transfer through an uninsulated slab on grade is calculated using a simple method developed by Kusuda. The seasonal and annual slab loads are graphed as a function of annual average soil temperature, Tm, for a variety of floor system...

  5. Development of a compensation chamber for use in a multiple condenser loop heat pipe

    E-Print Network [OSTI]

    Roche, Nicholas Albert

    2013-01-01

    The performance of many electronic devices is presently limited by heat dissipation rates. One potential solution lies in high-performance air-cooled heat exchangers like PHUMP, the multiple condenser loop heat pipe presented ...

  6. In-Situ Measurement of Crystalline Silicon Modules Undergoing Potential-Induced Degradation in Damp Heat Stress Testing for Estimation of Low-Light Power Performance

    SciTech Connect (OSTI)

    Hacke, P.; Terwilliger, K.; Kurtz, S.

    2013-08-01

    The extent of potential-induced degradation of crystalline silicon modules in an environmental chamber is estimated using in-situ dark I-V measurements and applying superposition analysis. The dark I-V curves are shown to correctly give the module power performance at 200, 600 and 1,000 W/m2 irradiance conditions, as verified with a solar simulator. The onset of degradation measured in low light in relation to that under one sun irradiance can be clearly seen in the module design examined; the time to 5% relative degradation measured in low light (200 W/m2) was 28% less than that of full sun (1,000 W/m2 irradiance). The power of modules undergoing potential-induced degradation can therefore be characterized in the chamber, facilitating statistical analyses and lifetime forecasting.

  7. Heating System Specification Specification of Heating System

    E-Print Network [OSTI]

    Day, Nancy

    Appendix A Heating System Specification /* Specification of Heating System (loosely based */ requestHeat : Room ­? bool; 306 #12; APPENDIX A. HEATING SYSTEM SPECIFICATION 307 /* user inputs */ living --- HEATERâ??ACTIVE --- ACTIVATINGâ??HEATER --- HEATERâ??RUNNING ; #12; APPENDIX A. HEATING SYSTEM SPECIFICATION

  8. Seasonal persistence of midlatitude total ozone anomalies

    E-Print Network [OSTI]

    Wirosoetisno, Djoko

    Seasonal persistence of midlatitude total ozone anomalies Article Published Version Fioletov, V. E. and Shepherd, T. G. (2003) Seasonal persistence of midlatitude total ozone anomalies. Geophysical Research persistence of midlatitude total ozone anomalies Vitali E. Fioletov Meteorological Service of Canada, Toronto

  9. Air-To-Water Heat Pumps with Radiant Delivery in Low Load Homes: Tucson, Arizona and Chico, California (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2013-11-01

    Space conditioning represents nearly 50% of average residential household energy consumption, highlighting the need to identify alternative cost-effective, energy-efficient cooling and heating strategies. As homes are better built, there is an increasing need for strategies that are particularly well suited for high performance, low load homes. ARBI researchers worked with two test homes in hot-dry climates to evaluate the in-situ performance of air-to-water heat pump (AWHP) systems, an energy efficient space conditioning solution designed to cost-effectively provide comfort in homes with efficient, safe, and durable operation. Two monitoring projects of test houses in hot-dry climates were initiated in 2010 to test this system. Both systems were fully instrumented and have been monitored over one year to capture complete performance data over the cooling and heating seasons. Results are used to quantify energy savings, cost-effectiveness, and system performance using different operating modes and strategies. A calibrated TRNSYS model was developed and used to evaluate performance in various climate regions. This strategy is most effective in tight, insulated homes with high levels of thermal mass (i.e. exposed slab floors).

  10. SMALL PARTICLE HEAT EXCHANGERS

    E-Print Network [OSTI]

    Hunt, A.J.

    2011-01-01

    The Small Particle Heat Exchange Receiver (SPHER) for Solarof the small particle heat exchange receiver (or SPHER), asabsorption process, the heat exchange to the gas, the choice

  11. Heat pump system

    DOE Patents [OSTI]

    Swenson, Paul F. (Cleveland, OH); Moore, Paul B. (Fedhaurn, FL)

    1982-01-01

    An air heating and cooling system for a building includes an expansion-type refrigeration circuit and a heat engine. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The heat engine includes a heat rejection circuit having a source of rejected heat and a primary heat exchanger connected to the source of rejected heat. The heat rejection circuit also includes an evaporator in heat exchange relation with the primary heat exchanger, a heat engine indoor heat exchanger, and a heat engine outdoor heat exchanger. The indoor heat exchangers are disposed in series air flow relationship, with the heat engine indoor heat exchanger being disposed downstream from the refrigeration circuit indoor heat exchanger. The outdoor heat exchangers are also disposed in series air flow relationship, with the heat engine outdoor heat exchanger disposed downstream from the refrigeration circuit outdoor heat exchanger. A common fluid is used in both of the indoor heat exchanges and in both of the outdoor heat exchangers. In a first embodiment, the heat engine is a Rankine cycle engine. In a second embodiment, the heat engine is a non-Rankine cycle engine.

  12. Industrial Waste Heat Recovery Using Heat Pipes 

    E-Print Network [OSTI]

    Ruch, M. A.

    1981-01-01

    For almost a decade now, heat pipes with secondary finned surfaces have been utilized in counter flow heat exchangers to recover sensible energy from industrial exhaust gases. Over 3,000 such heat exchangers are now in service, recovering...

  13. Combustion Exhaust Gas Heat to Power Using Thermoelectric Engines...

    Office of Environmental Management (EM)

    Documents & Publications TEG On-Vehicle Performance & Model Validation Thermoelectric Generator Performance for Passenger Vehicles Thermoelectric Waste Heat Recovery Program for...

  14. Heating systems for heating subsurface formations

    DOE Patents [OSTI]

    Nguyen, Scott Vinh (Houston, TX); Vinegar, Harold J. (Bellaire, TX)

    2011-04-26

    Methods and systems for heating a subsurface formation are described herein. A heating system for a subsurface formation includes a sealed conduit positioned in an opening in the formation and a heat source. The sealed conduit includes a heat transfer fluid. The heat source provides heat to a portion of the sealed conduit to change phase of the heat transfer fluid from a liquid to a vapor. The vapor in the sealed conduit rises in the sealed conduit, condenses to transfer heat to the formation and returns to the conduit portion as a liquid.

  15. Heat transfer and heat exchangers reference handbook

    SciTech Connect (OSTI)

    Not Available

    1991-01-15

    The purpose of this handbook is to provide Rocky Flats personnel with an understanding of the basic concepts of heat transfer and the operation of heat exchangers.

  16. Seasonally Flooded Grasslands -Grand CaymanSeasonally Flooded Grasslands -Grand Cayman 0 1 2 3 4 50.5

    E-Print Network [OSTI]

    Exeter, University of

    Seasonally Flooded Grasslands - Grand CaymanSeasonally Flooded Grasslands - Grand Cayman 0 1 2 3 4 Protected Areas Seasonally Flooded Grasslands V.A.1.N.g. #12;Seasonally Flooded Grasslands - Little CaymanSeasonally Flooded Grasslands - Little Cayman 0 0.5 1 1.5 2 2.50.25 Kilometers Cayman Islands National Biodiversity

  17. K-State Turfgrass Research Report of Progress 2006 TITLE: Membrane Lipid Composition and Heat Tolerance in Kentucky Bluegrass,

    E-Print Network [OSTI]

    ) Identify and quantify specific lipid compositional changes under heat stress; 3) and to discover. Heat stress may damage cell membranes in cool-season turfgrasses, causing leakage of cytoplasm period. Although the temperature was thereafter increased to induce heat stress for later lipids

  18. Integrated heat pump and heat storage system

    SciTech Connect (OSTI)

    Katz, A.

    1983-09-13

    An integrated heat pump and heat storage system is disclosed comprising a heat pump, a first conduit for supplying return air from an enclosure to the heat pump, a second conduit for supplying heated air from the heat pump to the enclosure, heat storage apparatus. A first damper is operative in a first orientation to permit return air from the enclosure to enter the first conduit and to prevent return air from passing through the heat storage apparatus and operative in a second orientation to cause return air to pass through the heat storage apparatus for being heated thereby before entering the first conduit. A second damper is operative in a first orientation to cause heated air from the second conduit to pass through the heat storage apparatus for giving up a portion of its heat for storage and operative in a second orientation to prevent heated air from the second conduit from passing through the heat storage apparatus and to permit the heated air from the second conduit to reach the enclosure. The heat storage apparatus may comprise phase change materials.

  19. Computer Control for IGBT Based Heat Load System with Rapid Response and Large Heat Flux

    E-Print Network [OSTI]

    Li, Yangmin

    system. So it can acquire the satisfactory performance, what is more, the heat load system combined heat flux within very short time, but it needs a very complicated welding power supply, and meantime, heating coils, etc. There are three power amplifiers: linear amplifier, on-off amplifier, and pulse width

  20. Energy Resources for Tornado Season | Department of Energy

    Office of Environmental Management (EM)

    Tornado Season Energy Resources for Tornado Season The aftermath of a tornado in Greensburg, Kansas. | Photo courtesy of Federal Emergency Mgmt. Agency, NREL 16290 The aftermath of...

  1. DEVELOPMENT OF THFEGENERAL ELECTRIC STIRLING ENGINE GAS HEAT PUMP

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    DEVELOPMENT OF THFEGENERAL ELECTRIC STIRLING ENGINE GAS HEAT PUMP R. C. Meier, Program Manager, Gas Heat Pump Program General Electric Company P. 0. Box 8555 Philadelphia, Pennsylvania 19101 FILE COPY DO NOT REMOVE SUMMARY The Stirling/Rankine Heat Activated Heat Pump is a high performance product for space

  2. Control and optimal operation of simple heat pump cycles

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Control and optimal operation of simple heat pump cycles Jørgen Bauck Jensen and Sigurd Skogestad in the opposite direction, the "heat pump", has recently become pop- ular. These two applications have also merged. The coefficients of performance for a heating cycle (heat pump) and a cooling cycle (refrigerator, A/C) are defined

  3. Dual source heat pump

    DOE Patents [OSTI]

    Ecker, Amir L. (Dallas, TX); Pietsch, Joseph A. (Dallas, TX)

    1982-01-01

    What is disclosed is a heat pump apparatus for conditioning a fluid characterized by a fluid handler and path for circulating the fluid in heat exchange relationship with a refrigerant fluid; at least two refrigerant heat exchangers, one for effecting heat exchange with the fluid and a second for effecting heat exchange between refrigerant and a heat exchange fluid and the ambient air; a compressor for efficiently compressing the refrigerant; at least one throttling valve for throttling liquid refrigerant; a refrigerant circuit; refrigerant; a source of heat exchange fluid; heat exchange fluid circulating device and heat exchange fluid circuit for circulating the heat exchange fluid in heat exchange relationship with the refrigerant; and valves or switches for selecting the heat exchangers and direction of flow of the refrigerant therethrough for selecting a particular mode of operation. The heat exchange fluid provides energy for defrosting the second heat exchanger when operating in the air source mode and also provides a alternate source of heat.

  4. Vegetation Dynamics in Seasonally Grazed Upland Systems 

    E-Print Network [OSTI]

    Pollock, Meg L

    This thesis addresses the effects of seasonality of grazing on vegetation dynamics. Background to the thesis is provided by the Hill Sheep and Native Woodland (HSNW) project, a system-scale experiment with the long-term ...

  5. Potential Economic Value of Seasonal Hurricane Forecasts

    E-Print Network [OSTI]

    Emanuel, Kerry Andrew

    This paper explores the potential utility of seasonal Atlantic hurricane forecasts to a hypothetical property insurance firm whose insured properties are broadly distributed along the U.S. Gulf and East Coasts. Using a ...

  6. THE EFFECT OF AIR-COOLING HEAT TREATMENTS ON THE STRUCTURE AND PROPERTIES OF Fe/4Cr/ 0.3C/2Mn ALLOY

    E-Print Network [OSTI]

    Rabe, T.H.

    2010-01-01

    published in Met. Trans. , Heat Treatment Conf. , The Metalstempered in (f). All heat treatments were performed for onefor the 1100 C heat treatment. Several undissolved spherical

  7. Table of Contents Our Season Page 3

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    1 #12;2 Table of Contents 2011-2012 Our Season Page 3 People Page 8 Outreach Page 11 Curricular-Curtain 546 $3,631.16 Hell In High Water-Rand 1252 $7,102.47 Solstice-Curtain 506 $2,583.42 Urinetown - Rand-stage season this spring. Hell in High Water by Marcus Gardley The Rand Theater Nov. 10, 11, 12, 16, 17, 18, 19

  8. Cascade heat recovery with coproduct gas production

    DOE Patents [OSTI]

    Brown, W.R.; Cassano, A.A.; Dunbobbin, B.R.; Rao, P.; Erickson, D.C.

    1986-10-14

    A process for the integration of a chemical absorption separation of oxygen and nitrogen from air with a combustion process is set forth wherein excess temperature availability from the combustion process is more effectively utilized to desorb oxygen product from the absorbent and then the sensible heat and absorption reaction heat is further utilized to produce a high temperature process stream. The oxygen may be utilized to enrich the combustion process wherein the high temperature heat for desorption is conducted in a heat exchange preferably performed with a pressure differential of less than 10 atmospheres which provides considerable flexibility in the heat exchange. 4 figs.

  9. Cascade heat recovery with coproduct gas production

    DOE Patents [OSTI]

    Brown, William R. (Zionsville, PA); Cassano, Anthony A. (Allentown, PA); Dunbobbin, Brian R. (Allentown, PA); Rao, Pradip (Allentown, PA); Erickson, Donald C. (Annapolis, MD)

    1986-01-01

    A process for the integration of a chemical absorption separation of oxygen and nitrogen from air with a combustion process is set forth wherein excess temperature availability from the combustion process is more effectively utilized to desorb oxygen product from the absorbent and then the sensible heat and absorption reaction heat is further utilized to produce a high temperature process stream. The oxygen may be utilized to enrich the combustion process wherein the high temperature heat for desorption is conducted in a heat exchange preferably performed with a pressure differential of less than 10 atmospheres which provides considerable flexibility in the heat exchange.

  10. A simplified model for heat transfer in heat exchangers and stack plates for thermoacoustic devices

    SciTech Connect (OSTI)

    Chen, Y.; Herman, C.

    1999-07-01

    A simplified model of heat transfer in heat exchangers and stack plates of thermoacoustic devices was developed. The model took advantage of previous results regarding the thermal behavior of the thermoacoustic core for investigations of the performance of heat exchangers attached to the core. Geometrical and operational parameters as well as thermophysical properties of the heat exchangers, the plate, and the working medium were organized into dimensionless groups that allowed to account for their impact on the performance of the heat exchangers. Numerical simulations with the model were carried out. Nonlinear temperature distributions and heat fluxes near the edge of the stack plate were observed. Effects of different parameters on the thermal performance of the heat exchangers were investigated.

  11. 7-117 The claim of a heat pump designer regarding the COP of the heat pump is to be evaluated. Assumptions The heat pump operates steadily.

    E-Print Network [OSTI]

    Bahrami, Majid

    7-47 7-117 The claim of a heat pump designer regarding the COP of the heat pump is to be evaluated. Assumptions The heat pump operates steadily. HP Wnet,in QH QL TL TH Analysis The maximum heat pump coefficient of performance would occur if the heat pump were completely reversible, 5.7 K026K300 K300 COP maxHP, LH H TT

  12. Test results of a Stirling engine utilizing heat exchanger modules with an integral heat pipe

    SciTech Connect (OSTI)

    Skupinski, R.C.; Tower, L.K.; Madi, F.J.; Brusk, K.D.

    1993-04-01

    The Heat Pipe Stirling Engine (HP-1000), a free-piston Stirling engine incorporating three heat exchanger modules, each having a sodium filled heat pipe, has been tested at the NASA-Lewis Research Center as part of the Civil Space Technology Initiative (CSTI). The heat exchanger modules were designed to reduce the number of potential flow leak paths in the heat exchanger assembly and incorporate a heat pipe as the link between the heat source and the engine. An existing RE-1000 free-piston Stirling engine was modified to operate using the heat exchanger modules. This paper describes heat exchanger module and engine performance during baseline testing. Condenser temperature profiles, brake power, and efficiency are presented and discussed.

  13. Heat Pump Water Heater Performance in

    Broader source: Energy.gov [DOE]

    This presentation was delivered at the U.S. Department of Energy Building America Technical Update meeting on April 29-30, 2013, in Denver, Colorado.

  14. Thermoelectrics Partnership: High Performance Thermoelectric Waste Heat

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCEDInstallers/ContractorsPhotovoltaicsState ofSavings for Specific2 DOE HydrogenScalable Thermo-

  15. PHYSICS DEPARTMENT Heat Transport in Evacuated Perlite Powder

    E-Print Network [OSTI]

    Gross, Rudolf

    , the long-term and seasonal storage of hot wa- ter up to T = 150 °C in solar thermal heating systems storage of thermal energy in industrial processes or in solar thermal power plants for electric power Application in Long-Term Hot Water Storages Master Thesis of Matthias Demharter

  16. Building America Webinar: New Construction Hybrid-Ductless Heat Pumps Study: Resistance is Futile

    Broader source: Energy.gov [DOE]

    This webinar focused on the use of ductless heat pumps (DHP) as a hybrid “all-electric” heating system in new high-performance homes.

  17. Foundation heat exchangers for residential ground source heat pump systems Numerical modeling and experimental validation

    SciTech Connect (OSTI)

    Xing, Lu [Oklahoma State University; Cullin, James [Oklahoma State University; Spitler, Jeffery [Oklahoma State University; Im, Piljae [ORNL; Fisher, Daniel [Oklahoma State University

    2011-01-01

    A new type of ground heat exchanger that utilizes the excavation often made for basements or foundations has been proposed as an alternative to conventional ground heat exchangers. This article describes a numerical model that can be used to size these foundation heat exchanger (FHX) systems. The numerical model is a two-dimensional finite-volume model that considers a wide variety of factors, such as soil freezing and evapotranspiration. The FHX numerical model is validated with one year of experimental data collected at an experimental house located near Oak Ridge, Tennessee. The model shows good agreement with the experimental data-heat pump entering fluid temperatures typically within 1 C (1.8 F) - with minor discrepancies due to approximations, such as constant moisture content throughout the year, uniform evapotranspiration over the seasons, and lack of ground shading in the model.

  18. A Study of Transient Behavior During Start-Up of Residential Heat Pumps 

    E-Print Network [OSTI]

    Katipamula, Srinivas

    1989-01-01

    An experimental and analytical study concerned with the transient performance of heat pumps is presented. A series of tests were performed to study and characterize the transient sensible and dehumidification performance of a heat pump...

  19. System Modeling of Gas Engine Driven Heat Pump

    SciTech Connect (OSTI)

    Mahderekal, Isaac [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Shen, Bo [ORNL] [ORNL; Vineyard, Edward [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL)

    2012-01-01

    To improve the system performance of the GHP, modeling and experimental study has been made by using desiccant system in cooling operation (particularly in high humidity operations) and suction line waste heat recovery to augment heating capacity and efficiency. The performance of overall GHP system has been simulated by using ORNL Modulating Heat Pump Design Software, which is used to predict steady-state heating and cooling performance of variable-speed vapor compression air-to-air heat pumps for a wide range of operational variables. The modeling includes: (1) GHP cycle without any performance improvements (suction liquid heat exchange and heat recovery) as a baseline (both in cooling and heating mode), (2) the GHP cycle in cooling mode with desiccant system regenerated by waste heat from engine incorporated, (3) GHP cycle in heating mode with heat recovery (recovered heat from engine). According to the system modeling results, by using desiccant system regenerated by waste heat from engine, the SHR can be lowered to 40%. The waste heat of the gas engine can boost the space heating efficiency by 25% in rated operating conditions.

  20. NOVA Making Stuff Season 2

    SciTech Connect (OSTI)

    Leombruni, Lisa; Paulsen, Christine Andrews

    2014-12-12

    Over the course of four weeks in fall 2013, 11.7 million Americans tuned in to PBS to follow host David Pogue as he led them in search of engineering and scientific breakthroughs poised to change our world. Levitating trains, quantum computers, robotic bees, and bomb-detecting plants—these were just a few of the cutting-edge innovations brought into the living rooms of families across the country in NOVA’s four-part series, Making Stuff: Faster, Wilder, Colder, and Safer. Each of the four one-hour programs gave viewers a behind-the-scenes look at novel technologies poised to change our world—showing them how basic research and scientific discovery can hold the keys to transforming how we live. Making Stuff Season 2 (MS2) combined true entertainment with educational value, creating a popular and engaging series that brought accessible science into the homes of millions. NOVA’s goal to engage the public with such technological innovation and basic research extended beyond the broadcast series, including a variety of online, educational, and promotional activities: original online science reporting, web-only short-form videos, a new online quiz-game, social media engagement and promotion, an educational outreach “toolkit” for science educators to create their own “makerspaces,” an online community of practice, a series of nationwide Innovation Cafés, educator professional development, a suite of teacher resources, an “Idealab,” participation in national conferences, and specialized station relation and marketing. A summative evaluation of the MS2 project indicates that overall, these activities helped make a significant impact on the viewers, users, and participants that NOVA reached. The final evaluation conducted by Concord Evaluation Group (CEG) confidently concluded that the broadcast, website, and outreach activities were successful at achieving the project’s intended impacts. CEG reported that the MS2 series and website content were successful in raising awareness and sparking interest in innovation, and increased public awareness that basic research leads to technological innovation; this interest was also sustained over a six month period. Efforts to create an online community of practice were also successful: the quality of collaboration increased, and community members felt supported while using Maker pedagogy. These findings provide clear evidence that large-scale science media projects like MS2 are an effective means of “moving the needle” on attitudes about and excitement for science. NOVA’s broadcast audience and ratings have always indicated that a large portion of the population is interested in and engages with educational science media on a weekly basis. Yet these evaluation results provide the empirical evidence that beyond being capable of attracting, maintaining, and growing a dedicated group of citizens interested in science, these shows—with their diverse content provided on a variety of media channels—are capable of sparking new interest in science, raising public awareness of the importance of science, and maintaining and growing that interest over time. In a country where approximately a quarter of the population doesn’t know the earth rotates around the sun,1 roughly half still don’t accept evolution,2 and about 20% don’t think climate change is happening,3 the importance of these findings cannot be overstated. The success of MS2 suggests that large-scale media projects dedicated to and linked by coverage of scientific “big ideas” are an effective means of shifting public opinion on—and improving understanding of—science. REFERENCES 1, 2 National Science Foundation, Science and Engineering Indicators (2014). Chapter 7: Science and Technology: Public Attitudes and Understanding. 3 Leiserowitz, A., Maibach, E., Roser-Renouf, C., Feinberg, G., & Rosenthal, S. (2014) Climate change in the American mind: April, 2014. Yale University and George Mason University. New Haven, CT: Yale Project on Climate Change Communication.

  1. Multiple source heat pump

    DOE Patents [OSTI]

    Ecker, Amir L. (Duncanville, TX)

    1983-01-01

    A heat pump apparatus for conditioning a fluid characterized by a fluid handler and path for circulating a fluid in heat exchange relationship with a refrigerant fluid, at least three refrigerant heat exchangers, one for effecting heat exchange with the fluid, a second for effecting heat exchange with a heat exchange fluid, and a third for effecting heat exchange with ambient air; a compressor for compressing the refrigerant; at least one throttling valve connected at the inlet side of a heat exchanger in which liquid refrigerant is vaporized; a refrigerant circuit; refrigerant; a source of heat exchange fluid; heat exchange fluid circuit and pump for circulating the heat exchange fluid in heat exchange relationship with the refrigerant; and valves or switches for selecting the heat exchangers and directional flow of refrigerant therethrough for selecting a particular mode of operation. Also disclosed are a variety of embodiments, modes of operation, and schematics therefor.

  2. Heat Plan DenmarkHeat Plan Denmark Anders Dyrelundy

    E-Print Network [OSTI]

    efficient use of renewable energy in district heating · individual heat pumps solar heating and wood pellets· individual heat pumps, solar heating and wood pellets 6Risø International Energy Conference 2009Heat Plan

  3. Heat Exchangers for Solar Water Heating Systems | Department...

    Energy Savers [EERE]

    Heat Exchangers for Solar Water Heating Systems Heat Exchangers for Solar Water Heating Systems Image of a heat exchanger. | Photo from iStockphoto.com Image of a heat exchanger. |...

  4. Heat-Of-Reaction Chemical Heat Pumps--Possible Configurations 

    E-Print Network [OSTI]

    Kirol, L. D.

    1986-01-01

    Chemical heat pumps utilize working fluids which undergo reversible chemical changes. Mechanically driven reactive heat pump cycles or, alternatively, heat driven heat pumps in which either heat engine or heat pump ...

  5. Introduction to Heat Exchangers

    E-Print Network [OSTI]

    Heller, Barbara

    . Since, the effectiveness can be written in terms of heat capacitance rate [W/K], C, and change in temperature [K], . The heat capacitance rate is defined in terms of mass flow rate [kg/s], , and specific heat: ! ! ! " # = ! ! "# ! ! ! - ! ! ! ! ! ! = ! !! ! ! ! ! = ! ! ! ! ! - ! ! ! ! ! "# ! ! ! - ! ! ! ! ! ! = ! ! ! ! ! - ! ! ! ! ! "# ! ! ! - ! ! ! ! ! Heat%Capacitance%Rate % ! = ! !! ! ! Heat%Capacitance%Rate%[W % ! = ! ! ! ! ! ! ! = ! ! !! ! ! ! max

  6. Heat Management in Thermoelectric Power Generators

    E-Print Network [OSTI]

    Zebarjadi, Mona

    2015-01-01

    Thermoelectric power generators are used to convert heat into electricity. Like any other heat engine, the performance of a thermoelectric generator increases as the temperature difference on the sides increases. It is generally assumed that as more heat is forced through the thermoelectric legs, their performance increases. Therefore, insulations are typically used to minimize the heat losses and to confine the heat transport through the thermoelectric legs. In this paper we show that to some extend it is beneficial to purposely open heat loss channels in order to establish a larger temperature gradient and therefore to increase the overall efficiency and achieve larger electric power output. We define a modified Biot number (Bi) as an indicator of requirements for sidewall insulation. We show that if Bi1, it lowers the conversion efficiency.

  7. Efficient Heat Engines and Heat Pumps (10 credits) The aim of the module is to introduce the various ideal thermodynamic cycles that form

    E-Print Network [OSTI]

    Birmingham, University of

    Efficient Heat Engines and Heat Pumps (10 credits) The aim of the module is to introduce the various ideal thermodynamic cycles that form the basis for power generation, heat pumping and IC Engines performance. Syllabus Heat Engines and Heat Pumps · Second Law of Thermodynamics, Concept

  8. CO2 Heat Pump Water Heater | Department of Energy

    Broader source: Energy.gov (indexed) [DOE]

    CO2 Heat Pump Water Heater Prototype
    Credit: Oak Ridge National Lab CO2 Heat Pump Water Heater Prototype Credit: Oak Ridge National Lab Lead Performer: Oak Ridge National...

  9. Future EfficientDynamics with Heat Recovery | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    EfficientDynamics with Heat Recovery Future EfficientDynamics with Heat Recovery A 15% increase in engine performance could be demonstrated with a Dual-Loop-Rankine and 10%...

  10. Automatic Tube Cleaning Systems for Condensers & Heat Exchangers 

    E-Print Network [OSTI]

    Someah, K.

    1993-01-01

    Condenser tube fouling contributes up to 50% of the total condenser tube heat transfer resistance. This fouling results in reduced heat exchanger performance, reduced production, increased operational cost, increased back pressure, increased tube...

  11. Energy Performance Aspects of a Florida Green Roof Part 2 

    E-Print Network [OSTI]

    Sonne, J.; Parker, D.

    2008-01-01

    the roof heat flux results and equipment efficiency assumptions. Based on this analysis the total estimated cooling and heating season savings for the green roof compared with the conventional roof, if the entire 3,300 square foot project roof were green...

  12. Pagosa Springs District Heating District Heating Low Temperature...

    Open Energy Info (EERE)

    Pagosa Springs District Heating District Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Pagosa Springs District Heating District Heating Low...

  13. City of Klamath Falls District Heating District Heating Low Temperatur...

    Open Energy Info (EERE)

    City of Klamath Falls District Heating District Heating Low Temperature Geothermal Facility Jump to: navigation, search Name City of Klamath Falls District Heating District Heating...

  14. San Bernardino District Heating District Heating Low Temperature...

    Open Energy Info (EERE)

    San Bernardino District Heating District Heating Low Temperature Geothermal Facility Jump to: navigation, search Name San Bernardino District Heating District Heating Low...

  15. Philip District Heating District Heating Low Temperature Geothermal...

    Open Energy Info (EERE)

    Philip District Heating District Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Philip District Heating District Heating Low Temperature Geothermal...

  16. Kethcum District Heating District Heating Low Temperature Geothermal...

    Open Energy Info (EERE)

    Kethcum District Heating District Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Kethcum District Heating District Heating Low Temperature Geothermal...

  17. Boise City Geothermal District Heating District Heating Low Temperatur...

    Open Energy Info (EERE)

    Boise City Geothermal District Heating District Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Boise City Geothermal District Heating District Heating...

  18. Midland District Heating District Heating Low Temperature Geothermal...

    Open Energy Info (EERE)

    Midland District Heating District Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Midland District Heating District Heating Low Temperature Geothermal...

  19. Northeast Home Heating Oil Reserve System Heating Oil, PIA Office...

    Broader source: Energy.gov (indexed) [DOE]

    Northeast Home Heating Oil Reserve System Heating Oil, PIA Office of Fossil Energy Headquaters Northeast Home Heating Oil Reserve System Heating Oil, PIA Office of Fossil Energy...

  20. Geothermal Heat Pump Profitability in Energy Services

    SciTech Connect (OSTI)

    1997-11-01

    If geothermal heat pumps (GHPs) are to make a significant mark in the market, we believe that it will be through energy service pricing contracts offered by retailcos. The benefits of GHPs are ideally suited to energy service pricing (ESP) contractual arrangements; however, few retailcos are thoroughly familiar with the benefits of GHPs. Many of the same barriers that have prevented GHPs from reaching their full potential in the current market environment remain in place for retailcos. A lack of awareness, concerns over the actual efficiencies of GHPs, perceptions of extremely high first costs, unknown records for maintenance costs, etc. have all contributed to limited adoption of GHP technology. These same factors are of concern to retailcos as they contemplate long term customer contracts. The central focus of this project was the creation of models, using actual GHP operating data and the experience of seasoned professionals, to simulate the financial performance of GHPs in long-term ESP contracts versus the outcome using alternative equipment. We have chosen two case studies, which may be most indicative of target markets in the competitive marketplace: A new 37,000 square foot office building in Toronto, Ontario; we also modeled a similar building under the weather conditions of Orlando, Florida. An aggregated residential energy services project using the mass conversion of over 4,000 residential units at Ft. Polk, Louisiana. Our method of analyses involved estimating equipment and energy costs for both the base case and the GHP buildings. These costs are input in to a cash flow analysis financial model which calculates an after-tax cost for the base and GHP case. For each case study customers were assumed to receive a 5% savings over their base case utility bill. A sensitivity analysis was then conducted to determine how key variables affect the attractiveness of a GHP investment.

  1. Heat pipe effect in porous medium

    SciTech Connect (OSTI)

    Joseph, M.

    1992-12-01

    In this thesis a parametric study of the thermal and hydrologic characteristics of the fractured porous tuffs at Yucca Mountain, Nevada was conducted. The effects of different fracture and matrix properties including permeability, thermal conductivity, specific heat, porosity, and tortuosity on heat pipe performance in the vicinity of the waste package were observed. Computer simulations were carried out using TOUGH code on a Cray YMP-2 supercomputer. None of the fracture parameters affected the heat pipe performance except the mobility of the liquid in the fracture. Matrix permeability and thermal conductivity were found to have significant effect on the heat pipe performance. The effect of mass injection was studied for liquid water and air injected at the fracture boundary. A high rate of mass injection was required to produce any effect on the heat pipe. The fracture-matrix equilibrium is influenced by the matrix permeability and the matrix thermal conductivity.

  2. SMALL PARTICLE HEAT EXCHANGERS

    E-Print Network [OSTI]

    Hunt, A.J.

    2011-01-01

    heat exchangers. These types of heat exchangers have limitedheat exchanger to solar collection systems that utilize linear trough- typenon-solar heat exchangers. These may be of the type used to

  3. Concentrating solar heat collector

    SciTech Connect (OSTI)

    Fattor, A.P.

    1980-09-23

    A heat storage unit is integrated with a collection unit providing a heat supply in off-sun times, and includes movable insulation means arranged to provide insulation during off-sun times for the heat storage unit.

  4. Absorption heat pump system

    DOE Patents [OSTI]

    Grossman, G.

    1982-06-16

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  5. Absorption heat pump system

    DOE Patents [OSTI]

    Grossman, Gershon (Oak Ridge, TN)

    1984-01-01

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  6. Locating Heat Recovery Opportunities 

    E-Print Network [OSTI]

    Waterland, A. F.

    1981-01-01

    Basic concepts of heat recovery are defined as they apply to the industrial community. Methods for locating, ranking, and developing heat recovery opportunities are presented and explained. The needs for useful heat 'sinks' are emphasized as equal...

  7. Woven heat exchanger

    DOE Patents [OSTI]

    Piscitella, R.R.

    1984-07-16

    This invention relates to a heat exchanger for waste heat recovery from high temperature industrial exhaust streams. In a woven ceramic heat exchanger using the basic tube-in-shell design, each heat exchanger consisting of tube sheets and tube, is woven separately. Individual heat exchangers are assembled in cross-flow configuration. Each heat exchanger is woven from high temperature ceramic fiber, the warp is continuous from tube to tube sheet providing a smooth transition and unitized construction.

  8. Building America Webinar: New Construction Hybrid-Ductless Heat Pumps Study: Resistance is Futile

    Office of Energy Efficiency and Renewable Energy (EERE)

    This webinar will focus on the use of ductless heat pumps (DHP) as a hybrid “all-electric” heating system in new high-performance homes. In a DHP/hybrid heating system, the DHP fan coil is located...

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

    E-Print Network [OSTI]

    Hong, Tainzhen

    2010-01-01

    tool for geothermal water loop heat pump systems, 9thInternational IEA Heat Pump Conference, Zürich, Switzerland,Performance of ground source heat pump system in a near-zero

  10. Impact of Solar Heat Gain on Radiant Floor Cooling System Design

    E-Print Network [OSTI]

    Feng, Jingjuan Dove; Schiavon, Stefano; Bauman, Fred

    2013-01-01

    7] B. Borresen, Floor heating and cooling of an atrium, in:thermal performance of floor heating systems, Solar Energy,discussed this issue for floor heating, but not cooling.

  11. Automatic control of electric thermal storage (heat) under real-time pricing. Final report

    SciTech Connect (OSTI)

    Daryanian, B.; Tabors, R.D.; Bohn, R.E. [Tabors Caramanis and Associates, Inc. (United States)

    1995-01-01

    Real-time pricing (RTP) can be used by electric utilities as a control signal for responsive demand-side management (DSM) programs. Electric thermal storage (ETS) systems in buildings provide the inherent flexibility needed to take advantage of variations in prices. Under RTP, optimal performance for ETS operations is achieved under market conditions where reductions in customers` costs coincide with the lowering of the cost of service for electric utilities. The RTP signal conveys the time-varying actual marginal cost of the electric service to customers. The RTP rate is a combination of various cost components, including marginal generation fuel and maintenance costs, marginal costs of transmission and distribution losses, and marginal quality of supply and transmission costs. This report describes the results of an experiment in automatic control of heat storage systems under RTP during the winter seasons of 1989--90 and 1990--91.

  12. Total Space Heat-

    Gasoline and Diesel Fuel Update (EIA)

    Revised: December, 2008 Total Space Heat- ing Cool- ing Venti- lation Water Heat- ing Light- ing Cook- ing Refrig- eration Office Equip- ment Com- puters Other All Buildings...

  13. Total Space Heat-

    Gasoline and Diesel Fuel Update (EIA)

    Released: September, 2008 Total Space Heat- ing Cool- ing Venti- lation Water Heat- ing Light- ing Cook- ing Refrig- eration Office Equip- ment Com- puters Other All Buildings*...

  14. Geothermal Heat Pumps

    Broader source: Energy.gov [DOE]

    Geothermal heat pumps are expensive to install but pay for themselves over time in reduced heating and cooling costs. Find out if one is right for your home.

  15. Performance Study of Swimming Pool Heaters

    SciTech Connect (OSTI)

    McDonald, R.J.

    2009-01-01

    The objective of this report is to perform a controlled laboratory study on the efficiency and emissions of swimming pool heaters based on a limited field investigation into the range of expected variations in operational parameters. Swimming pool heater sales trends have indicated a significant decline in the number of conventional natural gas-fired swimming pool heaters (NGPH). On Long Island the decline has been quite sharp, on the order of 50%, in new installations since 2001. The major portion of the decline has been offset by a significant increase in the sales of electric powered heat pump pool heaters (HPPH) that have been gaining market favor. National Grid contracted with Brookhaven National Laboratory (BNL) to measure performance factors in order to compare the relative energy, environmental and economic consequences of using one technology versus the other. A field study was deemed inappropriate because of the wide range of differences in actual load variations (pool size), geographic orientations, ground plantings and shading variations, number of hours of use, seasonal use variations, occupancy patterns, hour of the day use patterns, temperature selection, etc. A decision was made to perform a controlled laboratory study based on a limited field investigation into the range of expected operational variations in parameters. Critical to this are the frequency of use, temperature selection, and sizing of the heater to the associated pool heating loads. This would be accomplished by installing a limited amount of relatively simple compact field data acquisition units on selected pool installations. This data included gas usage when available and alternately heater power or gas consumption rates were inferred from the manufacturer's specifications when direct metering was not available in the field. Figure 1 illustrates a typical pool heater installation layout.

  16. THERMOSIPHON WATER HEATERS WITH HEAT EXCHANGERS

    E-Print Network [OSTI]

    Mertol, Atila

    2012-01-01

    The Performance of Solar Water Heater With Natural Ci rculperformance of solar thermos i phon water heaters with heatSolar Jubilee, Phoenix, AZ, June 2-6, 1980 THERMOSIPHON WATER HEATERS

  17. Heat pipes for NEP spacecraft radiators

    SciTech Connect (OSTI)

    Ernst, D.M.

    1981-01-01

    Reliable, low mass, passive radiators for the Nuclear Electric Propulsion Spacecraft require innovative system designs and the use of high performance, high temperature liquid metal heat pipes. This paper covers the evolution of the NEP spacecraft and radiator. 1 ref.

  18. Heat Recovery Design Considerations for Cogeneration Systems 

    E-Print Network [OSTI]

    Pasquinelli, D. M.; Burns, E. D.

    1985-01-01

    The design and integration of the heat recovery section, which includes the steam generation, auxiliary firing, and steam turbine modules, is critical to the overall performance and economics of cogeneration, systems. In gas turbine topping...

  19. Geothermal heat pumps for federal buildings

    SciTech Connect (OSTI)

    1999-09-02

    Geothermal heat pumps (GHPs) can provide significant energy savings to a wide range of Federal facilities. GHP equipment can be obtained and installed at no up-front cost through Energy Savings Performance Contracts (ESPCs) through energy service companies (ESCOs).

  20. Seasonal ozone variations in the upper mesosphere

    SciTech Connect (OSTI)

    Thomas, R.J. (Univ. of Colorado, Boulder (United States))

    1990-05-20

    The global daytime ozone was measured by the Solar Mesosphere Explorer satellite (SME) for 5 years. The measurements extend through the mesosphere, covering from 50 km to over 90 km. The ozone in the upper mesosphere varies annually by up to a factor of 3. The observed seasonal variations may be summarized in several different ways. From year to year there is a great deal of repeatability of these variations. This repeatability occurs in most of the upper mesosphere outside the tropics. Near 0.01 mbar (80 km) the mid- and high-latitude mixing ratio peaks each year in mid-April. A secondary maximum in the altitude profile of ozone density usually occurs near 85 km. Changes in this structure are directly related to the April maximum and other seasonal changes seen at 0.01 mbar. The changing seasonal structure produces a bump at the ozone mixing ratio minimum that is largest just after spring equinox. This perturbation to the mixing ratio profile seems to move upward during the first half of the year. The seasonal changes of ozone were analyzed in terms of annual and semiannual structure. The variations generally have both an annual and semiannual component depending on altitude and latitude. The phases of the variations change quickly with both altitude and latitude. The semiannual component peaks in April, over most of the upper mesosphere.

  1. 2005 Season Review Small Fruit and Grapes

    E-Print Network [OSTI]

    Ginzel, Matthew

    1 INDEX 2005 Season Review Small Fruit and Grapes Tree Fruit Plant Pathology Entomology Indiana Horticultural Congress Horticultural Therapy FFF05-09 December, 2005 Small Fruit and Grapes: Blueberries Large, especially on flowers of Arkan- sas Primocane Fruiters. ·Potato leafhoppers, very severe damage this year

  2. Mammalian Seasonal Rhythms: Behavior and Neuroendocrine Substrates

    E-Print Network [OSTI]

    Zucker, Irving

    . The amount and intensity of solar radiation varies with latitude; the greater the distance from the equator, the more pronounced the interseasonal differences in ambient temperature and solar radiation. Plant growth to melatonin in mammals to date." (Arendt, 2000) I. INTRODUCTION Seasonal phenotypes in behavior and physiology

  3. Gap between active and passive solar heating

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1985-01-01

    The gap between active and passive solar could hardly be wider. The reasons for this are discussed and advantages to narrowing the gap are analyzed. Ten years of experience in both active and passive systems are reviewed, including costs, frequent problems, performance prediction, performance modeling, monitoring, and cooling concerns. Trends are analyzed, both for solar space heating and for service water heating. A tendency for the active and passive technologies to be converging is observed. Several recommendations for narrowing the gap are presented.

  4. Direct fired heat exchanger

    DOE Patents [OSTI]

    Reimann, Robert C. (Lafayette, NY); Root, Richard A. (Spokane, WA)

    1986-01-01

    A gas-to-liquid heat exchanger system which transfers heat from a gas, generally the combustion gas of a direct-fired generator of an absorption machine, to a liquid, generally an absorbent solution. The heat exchanger system is in a counterflow fluid arrangement which creates a more efficient heat transfer.

  5. Woven heat exchanger

    DOE Patents [OSTI]

    Piscitella, Roger R. (Idaho Falls, ID)

    1987-01-01

    In a woven ceramic heat exchanger using the basic tube-in-shell design, each heat exchanger consisting of tube sheets and tube, is woven separately. Individual heat exchangers are assembled in cross-flow configuration. Each heat exchanger is woven from high temperature ceramic fiber, the warp is continuous from tube to tube sheet providing a smooth transition and unitized construction.

  6. Rotary magnetic heat pump

    DOE Patents [OSTI]

    Kirol, L.D.

    1987-02-11

    A rotary magnetic heat pump constructed without flow seals or segmented rotor accomplishes recuperation and regeneration by using split flow paths. Heat exchange fluid pumped through heat exchangers and returned to the heat pump splits into two flow components: one flowing counter to the rotor rotation and one flowing with the rotation. 5 figs.

  7. Rotary magnetic heat pump

    DOE Patents [OSTI]

    Kirol, Lance D. (Shelly, ID)

    1988-01-01

    A rotary magnetic heat pump constructed without flow seals or segmented rotor accomplishes recuperation and regeneration by using split flow paths. Heat exchange fluid pumped through heat exchangers and returned to the heat pump splits into two flow components: one flowing counter to the rotor rotation and one flowing with the rotation.

  8. Mass and Heat Recovery 

    E-Print Network [OSTI]

    Hindawai, S. M.

    2010-01-01

    In the last few years heat recovery was under spot and in air conditioning fields usually we use heat recovery by different types of heat exchangers. The heat exchanging between the exhaust air from the building with the fresh air to the building...

  9. Thermal Performance of Vegetative Roofing Systems

    SciTech Connect (OSTI)

    Desjarlais, Andre Omer [ORNL; Zaltash, Abdolreza [ORNL; Atchley, Jerald Allen [ORNL; Ennis, Mike J [ORNL

    2010-01-01

    Vegetative roofing, otherwise known as green or garden roofing, has seen tremendous growth in the last decade in the United States. The numerous benefits that green roofs provide have helped to fuel their resurgence in industrial and urban settings. There are many environmental and economical benefits that can be realized by incorporating a vegetative roof into the design of a building. These include storm-water retention, energy conservation, reduction in the urban heat island effect, increased longevity of the roofing membrane, the ability of plants to create biodiversity and filter air contaminants, and beautification of the surroundings by incorporating green space. The vegetative roof research project at Oak Ridge National Laboratory (ORNL) was initiated to quantify the thermal performance of various vegetative roofing systems relative to black and white roofs. Single Ply Roofing Institute (SPRI) continued its long-term commitment to cooperative research with ORNL in this project. Low-slope roof systems for this study were constructed and instrumented for continuous monitoring in the mixed climate of East Tennessee. This report summarizes the results of the annual cooling and heating loads per unit area of three vegetative roofing systems with side-by-side comparison to black and white roofing systems as well as a test section with just the growing media without plants. Results showed vegetative roofs reduced heat gain (reduced cooling loads) compared to the white control system due to the thermal mass, extra insulation, and evapo-transpiration associated with the vegetative roofing systems. The 4-inch and tray systems reduced the heat gain by approximately 61%, while the reduction with the 8-inch vegetative roof was found to be approximately 67%. The vegetative roofing systems were more effective in reducing heat gain than in reducing heat losses (heating loads). The reduction in heat losses for the 4-inch and tray systems were found to be approximately 40% in the mixed climate of East Tennessee. It should be noted that these values are climate dependent. Vegetative roofs also reduced the temperature (heat exposure) and temperature fluctuations (thermal stress) experienced by the membrane. In the cooling season of East Tennessee, the average peak temperature of the 4-inch and tray systems was found to be approximately 94 F cooler than the control black roofing system. The average temperature fluctuations at the membrane for the 4-inch and tray systems were found to be approximately 10 F compared to 125 F for black and 64 F for white systems. As expected, the 8-inch vegetative roof had the lowest fluctuations at approximately 2 F. Future work will include modeling of the energy performance of vegetative roof panels in the test climate of East Tennessee. The validated model then will be used to predict energy use in roofs with different insulation levels and in climates different from the test climate.

  10. "Nanotechnology Enabled Advanced Industrial Heat Transfer Fluids"

    SciTech Connect (OSTI)

    Dr. Ganesh Skandan; Dr. Amit Singhal; Mr. Kenneth Eberts; Mr. Damian Sobrevilla; Prof. Jerry Shan; Stephen Tse; Toby Rossmann

    2008-06-12

    ABSTRACT Nanotechnology Enabled Advanced industrial Heat Transfer Fluids” Improving the efficiency of Industrial Heat Exchangers offers a great opportunity to improve overall process efficiencies in diverse industries such as pharmaceutical, materials manufacturing and food processing. The higher efficiencies can come in part from improved heat transfer during both cooling and heating of the material being processed. Additionally, there is great interest in enhancing the performance and reducing the weight of heat exchangers used in automotives in order to increase fuel efficiency. The goal of the Phase I program was to develop nanoparticle containing heat transfer fluids (e.g., antifreeze, water, silicone and hydrocarbon-based oils) that are used in transportation and in the chemical industry for heating, cooling and recovering waste heat. Much work has been done to date at investigating the potential use of nanoparticle-enhanced thermal fluids to improve heat transfer in heat exchangers. In most cases the effect in a commercial heat transfer fluid has been marginal at best. In the Phase I work, we demonstrated that the thermal conductivity, and hence heat transfer, of a fluid containing nanoparticles can be dramatically increased when subjected to an external influence. The increase in thermal conductivity was significantly larger than what is predicted by commonly used thermal models for two-phase materials. Additionally, the surface of the nanoparticles was engineered so as to have a minimal influence on the viscosity of the fluid. As a result, a nanoparticle-laden fluid was successfully developed that can lead to enhanced heat transfer in both industrial and automotive heat exchangers

  11. Heat Treating Apparatus

    DOE Patents [OSTI]

    De Saro, Robert (Annandale, NJ); Bateman, Willis (Sutton Colfield, GB)

    2002-09-10

    Apparatus for heat treating a heat treatable material including a housing having an upper opening for receiving a heat treatable material at a first temperature, a lower opening, and a chamber therebetween for heating the heat treatable material to a second temperature higher than the first temperature as the heat treatable material moves through the chamber from the upper to the lower opening. A gas supply assembly is operatively engaged to the housing at the lower opening, and includes a source of gas, a gas delivery assembly for delivering the gas through a plurality of pathways into the housing in countercurrent flow to movement of the heat treatable material, whereby the heat treatable material passes through the lower opening at the second temperature, and a control assembly for controlling conditions within the chamber to enable the heat treatable material to reach the second temperature and pass through the lower opening at the second temperature as a heated material.

  12. Integrated heat pump system

    SciTech Connect (OSTI)

    Reedy, W.R.

    1988-03-01

    An integrated heat pump and hot water system is described that includes: a heat pump having an indoor heat exchanger and an outdoor heat exchanger that are selectively connected to the suction line and the discharge line respectively of a compressor by a flow reversing means, and to each other by a liquid line having an expansion device mounted therein, whereby heating and cooling is provided to an indoor comfort zone by cycling the flow reversing means, a refrigerant to water heat exchanger having a hot water flow circuit in heat transfer relation with a first refrigerant condensing circuit and a second refrigerant evaporating circuit, a connection mounted in the liquid between the indoor heat exchanger and the expansion device, control means for regulating the flow of refrigerant through the refrigerant to water heat exchanger to selectively transfer heat into and out of the hot water flow circuit.

  13. Thulium-170 heat source

    DOE Patents [OSTI]

    Walter, Carl E. (Pleasanton, CA); Van Konynenburg, Richard (Livermore, CA); VanSant, James H. (Tracy, CA)

    1992-01-01

    An isotopic heat source is formed using stacks of thin individual layers of a refractory isotopic fuel, preferably thulium oxide, alternating with layers of a low atomic weight diluent, preferably graphite. The graphite serves several functions: to act as a moderator during neutron irradiation, to minimize bremsstrahlung radiation, and to facilitate heat transfer. The fuel stacks are inserted into a heat block, which is encased in a sealed, insulated and shielded structural container. Heat pipes are inserted in the heat block and contain a working fluid. The heat pipe working fluid transfers heat from the heat block to a heat exchanger for power conversion. Single phase gas pressure controls the flow of the working fluid for maximum heat exchange and to provide passive cooling.

  14. Solar Heat-Pipe Receiver Wick Modeling

    SciTech Connect (OSTI)

    Andraka, C.E.

    1998-12-21

    Stirling-cycle engines have been identified as a promising technology for the conversion of concentrated solar energy into usable electrical power. In previous experimented work, we have demonstrated that a heat pipe receiver can significantly improve system performance-over a directly-illuminated heater head. The design and operating conditions of a heat pipe receiver differ significantly from typical laboratory heat pipes. New wick structures have been developed to exploit the characteristics of the solar generation system. Typically, these wick structures allow vapor generation within the wick. Conventional heat pipe models do not handle this enhancement yet it can more than double the performance of the wick. In this study, I develop a steady-state model of a boiling-enhanced wick for a solar heat pipe receiver. The model is used for design-point calculations and is written in FORTRAN90. Some limited comparisons have been made with actual test data.

  15. Thermoelectric heat exchange element

    DOE Patents [OSTI]

    Callas, James J. (Peoria, IL); Taher, Mahmoud A. (Peoria, IL)

    2007-08-14

    A thermoelectric heat exchange module includes a first substrate including a heat receptive side and a heat donative side and a series of undulatory pleats. The module may also include a thermoelectric material layer having a ZT value of 1.0 or more disposed on at least one of the heat receptive side and the heat donative side, and an electrical contact may be in electrical communication with the thermoelectric material layer.

  16. Acoustically Enhanced Boiling Heat Transfer

    E-Print Network [OSTI]

    Z. W. Douglas; M. K. Smith; A. Glezer

    2008-01-07

    An acoustic field is used to increase the critical heat flux (CHF) of a flat-boiling-heat-transfer surface. The increase is a result of the acoustic effects on the vapor bubbles. Experiments are performed to explore the effects of an acoustic field on vapor bubbles in the vicinity of a rigid-heated wall. Work includes the construction of a novel heater used to produce a single vapor bubble of a prescribed size and at a prescribed location on a flatboiling surface for better study of an individual vapor bubble's reaction to the acoustic field. Work also includes application of the results from the single-bubble heater to a calibrated-copper heater used for quantifying the improvements in CHF.

  17. Cooling, Heating, and Power for Commercial Buildings - Benefits...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Commercial Buildings - Benefits Analysis, April 2002 Cooling, Heating, and Power for Commercial Buildings - Benefits Analysis, April 2002 In this paper, an analysis was performed...

  18. Space Heating and Cooling Products and Services | Department...

    Broader source: Energy.gov (indexed) [DOE]

    Air Conditioning Research Institute A directory listing air conditioning and heat pump products that meet energy performance tiers established by the Consortium for Energy...

  19. Effects of solar photovoltaic panels on roof heat transfer

    E-Print Network [OSTI]

    Dominguez, Anthony; Kleissl, Jan; Luvall, Jeffrey C

    2011-01-01

    the energy performance of  photovoltaic roofs, ASHRAE Trans A thermal model for photovoltaic systems, Solar Energy, Effects of Solar Photovoltaic Panels on Roof Heat Transfer 

  20. Heat pipe cooled heat rejection subsystem modelling for nuclear electric propulsion. Final report

    SciTech Connect (OSTI)

    Moriarty, M.P.

    1993-11-01

    NASA LeRC is currently developing a FORTRAN based computer model of a complete nuclear electric propulsion (NEP) vehicle that can be used for piloted and cargo missions to the Moon or Mars. Proposed designs feature either a Brayton or a K-Rankine power conversion cycle to drive a turbine coupled with rotary alternators. Both ion and magnetoplasmodynamic (MPD) thrusters will be considered in the model. In support of the NEP model, Rocketdyne is developing power conversion, heat rejection, and power management and distribution (PMAD) subroutines. The subroutines will be incorporated into the NEP vehicle model which will be written by NASA LeRC. The purpose is to document the heat pipe cooled heat rejection subsystem model and its supporting subroutines. The heat pipe cooled heat rejection subsystem model is designed to provide estimate of the mass and performance of the equipment used to reject heat from Brayton and Rankine cycle power conversion systems. The subroutine models the ductwork and heat pipe cooled manifold for a gas cooled Brayton; the heat sink heat exchanger, liquid loop piping, expansion compensator, pump and manifold for a liquid loop cooled Brayton; and a shear flow condenser for a K-Rankine system. In each case, the final heat rejection is made by way of a heat pipe radiator. The radiator is sized to reject the amount of heat necessary.

  1. Building America Webinar: High Performance Space Conditioning...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    I: Heating and Cooling with Mini-Splits in the Northeast Building America Webinar: High Performance Space Conditioning Systems, Part I: Heating and Cooling with Mini-Splits in the...

  2. Minor League Fan Satisfaction with the Season Ticket Selling Process 

    E-Print Network [OSTI]

    Reese, Jason D.

    2011-08-08

    The purpose of this study was to assess satisfaction with the season ticket selling process administered by a minor league baseball franchise. Minor league sport organizations rely heavily on season ticket sales and retention, therefore, knowing...

  3. Energy Risk Predictions for the 2015 Hurricane Season | Department...

    Office of Environmental Management (EM)

    Risk Predictions for the 2015 Hurricane Season Energy Risk Predictions for the 2015 Hurricane Season This presentation is from a DOE-NASEO webinar held June 23, 2015, on...

  4. St. Augustinegrass Warm-season turfgrass. Prefers full sun, but

    E-Print Network [OSTI]

    Ishida, Yuko

    St. Augustinegrass Warm-season turfgrass. Prefers full sun, but has a high tolerance for shade-season grass. It does best in full sun and high temperatures. Goes dormant and turns brown in winter. Very

  5. The Dhiban Excavation and Development Project's 2005 Season

    E-Print Network [OSTI]

    2010-01-01

    The Dh?bån Excavation and Development Project’s 2005 SeasonThe Dh?bån Excavation and Development Project’s 2005 SeasonDh?bån Excavation and Development Project (DEDP hereafter)

  6. Seasonal climatology of winddriven circulation on the New Jersey Shelf

    E-Print Network [OSTI]

    season and more to the right of the wind during the stratified season. During the stratified summer et al., 2008], river dis- charge [Fong and Geyer, 2001; ByoungJu and Wilkin, 2007; Chant et al., 2008

  7. Seasonal sand level changes on southern california beaches

    E-Print Network [OSTI]

    Yates, Marissa L.

    2009-01-01

    Guza, R. Gutierrez, and R. Seymour, 2008: A Technique forW.C. O’ Reilly, and R.J. Seymour, 2009: Overview of SeasonalW.C. O’Reilly, and R.J. Seymour, 2009: Seasonal Persis-

  8. Seasonal Sand Level Changes on Southern California Beaches

    E-Print Network [OSTI]

    Yates, Marissa L

    2009-01-01

    Guza, R. Gutierrez, and R. Seymour, 2008: A Technique forW.C. O’ Reilly, and R.J. Seymour, 2009: Overview of SeasonalW.C. O’Reilly, and R.J. Seymour, 2009: Seasonal Persis-

  9. No. 2 heating oil/propane program. Final report, 1990/91

    SciTech Connect (OSTI)

    McBrien, J.

    1991-06-01

    During the 1990/91 heating season, the Massachusetts Division of Energy Resources (DOER) participated in a joint data collection program between several state energy offices and the federal Department of Energy`s (DOE) Energy Information Administration (EIA). The purpose of the program was to collect and monitor retail and wholesale heating oil and propane prices and inventories from October 1990 through March 1991. This final report begins with an overview of the unique events which had an impact on the reporting period. Next, the report summarizes the results from the residential heating oil and propane price surveys conducted by DOER over the 1990/91 heating season. The report also incorporates the wholesale heating oil and propane prices and inventories collected by the EIA and distributed to the states.

  10. No. 2 heating oil/propane program. Final report, 1992/93

    SciTech Connect (OSTI)

    McBrien, J.

    1993-05-01

    During the 1992--93 heating season, the Massachusetts Division Energy Resources (DOER) participated in a joint data collection program between several state energy offices and the federal Department of Energy`s (DOE) Energy Information Administration (EIA). The purpose of the program was to collect and monitor retail and wholesale heating oil and propane prices and inventories from October, 1992 through March, 1993. This final report begins with an overview of the unique events which had an impact on the petroleum markets prior to and during the reporting period. Next, the report summarizes the results from residential heating oil and propane price surveys conducted by DOER over the 1992--93 heating season. The report also incorporates the wholesale heating oil and propane prices and inventories collected by the EIA and distributed to the states. Finally, the report outlines DOER`s use of the data.

  11. Heat flux solarimeter

    SciTech Connect (OSTI)

    Sartarelli, A.; Vera, S.; Cyrulies, E.; Echarri, R.; Samson, I.

    2010-12-15

    The solarimeter presented in this work is easy to assemble. It is calibrated and its performance is validated by means of Hottel's method. Finally, the curves obtained with this solarimeter are compared to the ones obtained with a commercial solarimeter. This device is based on the evaluation of the heat flow in a metal rod. In consequence, measurements are not affected by ambient temperature variations. On the other hand, there is a linear relationship between the temperatures measured at the rod ends and the incident radiation, as can be concluded both from the theory of its operation and the calibration lines obtained. The results obtained from the global irradiance measurements in the area of Los Polvorines (Buenos Aires Province), together with a preliminary evaluation of the solarimeter's response time, are presented in this work. (author)

  12. Holographic Heat Engines

    E-Print Network [OSTI]

    Clifford V. Johnson

    2014-09-04

    It is shown that in theories of gravity where the cosmological constant is considered a thermodynamic variable, it is natural to use black holes as heat engines. Two examples are presented in detail using AdS charged black holes as the working substance. We notice that for static black holes, the maximally efficient traditional Carnot engine is also a Stirling engine. The case of negative cosmological constant supplies a natural realization of these engines in terms of the field theory description of the fluids to which they are holographically dual. We first propose a precise picture of how the traditional thermodynamic dictionary of holography is extended when the cosmological constant is dynamical and then conjecture that the engine cycles can be performed by using renormalization group flow. We speculate about the existence of a natural dual field theory counterpart to the gravitational thermodynamic volume.

  13. Warm-Season (C4) Grasses Lowell E. Moser

    E-Print Network [OSTI]

    -season perennial grasses as biomass feedstock candidates (Table II-I). Most of this research has focused

  14. Reduce Waste and Save Energy this Holiday Season

    Office of Energy Efficiency and Renewable Energy (EERE)

    Reduce waste and save energy this holiday season whether you're shopping, eating, partying, decorating, or wrapping.

  15. Proceedings of HT2009 2009 ASME Summer Heat Transfer Conference

    E-Print Network [OSTI]

    Hidrovo, Carlos H.

    , TX, USA Carlos H. Hidrovo The University of Texas at Austin Austin, TX, USA ABSTRACT Heat pipes in a heat pipe is done passively by means of a wicking structure that induces capillary-driven flow from measurements of baseline mesh wicks and nanowicks. Since the thermal performance of most heat pipes is usually

  16. An integrated heat pump storage system for year-round off-peak electrical energy use

    SciTech Connect (OSTI)

    Russell, L.D.; Forbes, R.E.; Hilson, D.W.

    1982-05-01

    An integrated system that provides for primarily off-peak electrical energy use and heat storage during the heating season, cooling storage during the cooling season, and hot water heating during both seasons was evaluated in this project. Results indicate that such a system is feasible and can be employed to shift electrical energy use from peak to off-peak periods. Further, this shifting of energy use can be done with whatever timing is desired year-round to assist with load-leveling for the utility. Results indicate potential for both residential and commercial applications. It is concluded that widespread use of such systems could lead to significant benefits for electrical power utilities and their customers.

  17. Turning low solar heat gain windows into energy savers in winter

    SciTech Connect (OSTI)

    Feuermann, D.; Novoplansky, A. [Ben-Gurion Univ. of the Negev, Sede Boker (Israel). Jacob Blaustein Inst. for Desert Research

    1996-10-01

    The reduction in summer peak cooling loads of buildings with a large ratio of window to floor areas is often achieved by windows with a low solar heat gain coefficient (SHGC). These windows are typically double glazed with the exterior pane tinted or selectively absorbing. Absorbed solar radiation is rejected to the environment. This is undesirable in the cold season. The authors suggest that by turning south-facing windows by 180{degree} for the duration of the cold season, the solar heat gain of these windows can be increased significantly. By means of a computer simulation, they estimate seasonal energy savings for a model room in several climates. The effect of building heat capacity on the savings is also studied. Windows whose positions can be reversed for ease of cleaning are commercially available. This study shows that in a suitable climate the achievable savings easily compensate for the additional effort and possible investment over the lifetime of the window.

  18. Heat Management Strategy Trade Study

    SciTech Connect (OSTI)

    Nick Soelberg; Steve Priebe; Dirk Gombert; Ted Bauer

    2009-09-01

    This Heat Management Trade Study was performed in 2008-2009 to expand on prior studies in continued efforts to analyze and evaluate options for cost-effectively managing SNF reprocessing wastes. The primary objective was to develop a simplified cost/benefit evaluation for spent nuclear fuel (SNF) reprocessing that combines the characteristics of the waste generated through reprocessing with the impacts of the waste on heating the repository. Under consideration were age of the SNF prior to reprocessing, plutonium and minor actinide (MA) separation from the spent fuel for recycle, fuel value of the recycled Pu and MA, age of the remaining spent fuel waste prior to emplacement in the repository, length of time that active ventilation is employed in the repository, and elemental concentration and heat limits for acceptable glass waste form durability. A secondary objective was to identify and qualitatively analyze remaining issues such as (a) impacts of aging SNF prior to reprocessing on the fuel value of the recovered fissile materials, and (b) impact of reprocessing on the dose risk as developed in the Yucca Mountain Total System Performance Assessment (TSPA). Results of this study can be used to evaluate different options for managing decay heat in waste streams from spent nuclear fuel.

  19. AT 351 Lab 3: Seasons and Surface Temperature (Ch. 3)

    E-Print Network [OSTI]

    Rutledge, Steven

    an important role in an area's local vertical temperature distribution. Below, Figure 1 shows the verticalAT 351 Lab 3: Seasons and Surface Temperature (Ch. 3) Question #1: Seasons (20 pts) A. In your own words, describe the cause of the seasons. B. In the Northern Hemisphere we are closer to the sun during

  20. Improving climate change detection through optimal seasonal averaging: the

    E-Print Network [OSTI]

    Wirosoetisno, Djoko

    Improving climate change detection through optimal seasonal averaging: the case of the North. (2015) Improving climate change detection through optimal seasonal averaging: the case of the North;Improving climate change detection through optimal seasonal averaging:1 the case of the North Atlantic jet

  1. Large seasonal swings in leaf area of Amazon rainforests

    E-Print Network [OSTI]

    Myneni, Ranga B.

    tropical forests stud- ied to date display seasonal variations in the presence of new leaves, flowers of 25% in a majority of the Amazon rainforests. This seasonal cycle is timed to the seasonality of solar radiation in a manner that is suggestive of anticipatory and opportunistic pat- terns of net leaf flushing

  2. Part 1. Energy and Mass Solar Radiation and the Seasons

    E-Print Network [OSTI]

    Tang, Youmin

    Part 1. Energy and Mass Chapter 2. Solar Radiation and the Seasons #12;Introduction Solar Radiation radiation = 10 m peak #12;#12;The Solar Constant Energy intensity decreases in proportion to the distance of the Earth's Seasons Orbital alignment to the Sun = seasonal variations in solar energy Revolution

  3. Effect of different heat treatments during processing of soybean meal in a commercial solvent-extraction plant on the performance of pigs weaned at four weeks of age and growing swine 

    E-Print Network [OSTI]

    Hansen, Blaine Curt

    1984-01-01

    (P). 05), although diet 3 had numerically betr. er gains (. 59 vs . 55 kg/d) and F/G (4. 07 vs 4. 41). Diet 1 failed to support normal growth (. 47 kg/d), however, F/G was similar to diet 2 (4. 36). It would appear that application of heat up... range in heat treatments (HT) than is usually found among commercially available SBM. The SBM were de- signated in ascending order of HT as Under, Normal, Over and Rumen Escape (RE). The Normal meal was processed us? ing standard operating conditions...

  4. IEA Heat Pump Conference 2011, 16 -19 May 2011, Tokyo, Japan ENERGY EFFICIENT AIR TO AIR HEAT PUMP OPERATING WITH

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    00149 -1- 10th IEA Heat Pump Conference 2011, 16 - 19 May 2011, Tokyo, Japan ENERGY EFFICIENT AIR TO AIR HEAT PUMP OPERATING WITH R-1234yf Sorina Mortada, Ph.D. student, Center for Energy and Processes Abstract: Significant improvements in energy performance of air-to-air heat pumps are the major reason

  5. Heat transfer system

    DOE Patents [OSTI]

    Not Available

    1980-03-07

    A heat transfer system for a nuclear reactor is described. Heat transfer is accomplished within a sealed vapor chamber which is substantially evacuated prior to use. A heat transfer medium, which is liquid at the design operating temperatures, transfers heat from tubes interposed in the reactor primary loop to spaced tubes connected to a steam line for power generation purposes. Heat transfer is accomplished by a two-phase liquid-vapor-liquid process as used in heat pipes. Condensible gases are removed from the vapor chamber through a vertical extension in open communication with the chamber interior.

  6. Heat transfer system

    DOE Patents [OSTI]

    McGuire, Joseph C. (Richland, WA)

    1982-01-01

    A heat transfer system for a nuclear reactor. Heat transfer is accomplished within a sealed vapor chamber which is substantially evacuated prior to use. A heat transfer medium, which is liquid at the design operating temperatures, transfers heat from tubes interposed in the reactor primary loop to spaced tubes connected to a steam line for power generation purposes. Heat transfer is accomplished by a two-phase liquid-vapor-liquid process as used in heat pipes. Condensible gases are removed from the vapor chamber through a vertical extension in open communication with the chamber interior.

  7. Wound tube heat exchanger

    DOE Patents [OSTI]

    Ecker, Amir L. (Duncanville, TX)

    1983-01-01

    What is disclosed is a wound tube heat exchanger in which a plurality of tubes having flattened areas are held contiguous adjacent flattened areas of tubes by a plurality of windings to give a double walled heat exchanger. The plurality of windings serve as a plurality of effective force vectors holding the conduits contiguous heat conducting walls of another conduit and result in highly efficient heat transfer. The resulting heat exchange bundle is economical and can be coiled into the desired shape. Also disclosed are specific embodiments such as the one in which the tubes are expanded against their windings after being coiled to insure highly efficient heat transfer.

  8. Heat pipe technology development for high temperature space radiator applications

    SciTech Connect (OSTI)

    Merrigan, M.A.; Keddy, E.S.; Sena, J.T.; Elder, M.G.

    1984-01-01

    Technology requirements for heat pipe radiators, potentially among the lightest weight systems for space power applications, include flexible elements, and improved specific radiator performance(kg/kW). For these applications a flexible heat pipe capable of continuous operation through an angle of 180/sup 0/ has been demonstrated. The effect of bend angle on the heat pipe temperature distribution is reviewed. An analysis of lightweight membrane heat pipe radiators that use surface tension forces for fluid containment has been conducted. The design analysis of these lightweight heat pipes is described and a potential application in heat rejection systems for space nuclear power plants outlined.

  9. Consolidated Electric Cooperative- Heat Pump and Water Heating Rebates

    Office of Energy Efficiency and Renewable Energy (EERE)

    Consolidated Electric Cooperative provides rebates to residential customers who install electric water heaters, dual-fuel heating system or geothermal heat pumps. A dual-fuel heating systems...

  10. Total Space Heat-

    Gasoline and Diesel Fuel Update (EIA)

    Survey: Energy End-Use Consumption Tables Total Space Heat- ing Cool- ing Venti- lation Water Heat- ing Light- ing Cook- ing Refrig- eration Office Equip- ment Com- puters Other...

  11. Fusion heating technology

    SciTech Connect (OSTI)

    Cole, A.J.

    1982-06-01

    John Lawson established the criterion that in order to produce more energy from fusion than is necessary to heat the plasma and replenish the radiation losses, a minimum value for both the product of plasma density and confinement time t, and the temperature must be achieved. There are two types of plasma heating: neutral beam and electromagnetic wave heating. A neutral beam system is shown. Main development work on negative ion beamlines has focused on the difficult problem of the production of high current sources. The development of a 30 keV-1 ampere multisecond source module is close to being accomplished. In electromagnetic heating, the launcher, which provides the means of coupling the power to the plasma, is most important. The status of heating development is reviewed. Electron cyclotron resonance heating (ECRH), lower hybrid heating (HHH), and ion cyclotron resonance heating (ICRH) are reviewed.

  12. Photovoltaic roof heat flux

    E-Print Network [OSTI]

    Samady, Mezhgan Frishta

    2011-01-01

    designs (relatively) Photovoltaic Solar P a n e l AtmosphereCALIFORNIA, SAN DIEGO Photovoltaic Roof Heat Flux A ThesisABSTRACT OF T H E THESIS Photovoltaic Roof Heat Flux by

  13. Photovoltaic roof heat flux

    E-Print Network [OSTI]

    Samady, Mezhgan Frishta

    2011-01-01

    influence on the heat transfer as the radiation. Since thethe heat transfer analysis, the difference of net radiationheat transfer involved i n this project were conduction, convection and radiation.

  14. Abrasion resistant heat pipe

    DOE Patents [OSTI]

    Ernst, D.M.

    1984-10-23

    A specially constructed heat pipe is described for use in fluidized bed combustors. Two distinct coatings are spray coated onto a heat pipe casing constructed of low thermal expansion metal, each coating serving a different purpose. The first coating forms aluminum oxide to prevent hydrogen permeation into the heat pipe casing, and the second coating contains stabilized zirconium oxide to provide abrasion resistance while not substantially affecting the heat transfer characteristics of the system.

  15. Abrasion resistant heat pipe

    DOE Patents [OSTI]

    Ernst, Donald M. (Leola, PA)

    1984-10-23

    A specially constructed heat pipe for use in fluidized bed combustors. Two distinct coatings are spray coated onto a heat pipe casing constructed of low thermal expansion metal, each coating serving a different purpose. The first coating forms aluminum oxide to prevent hydrogen permeation into the heat pipe casing, and the second coating contains stabilized zirconium oxide to provide abrasion resistance while not substantially affecting the heat transfer characteristics of the system.

  16. Solar heat receiver

    DOE Patents [OSTI]

    Hunt, A.J.; Hansen, L.J.; Evans, D.B.

    1982-09-29

    A receiver is described for converting solar energy to heat a gas to temperatures from 700 to 900/sup 0/C. The receiver is formed to minimize impingement of radiation on the walls and to provide maximum heating at and near the entry of the gas exit. Also, the receiver is formed to provide controlled movement of the gas to be heated to minimize wall temperatures. The receiver is designed for use with gas containing fine heat absorbing particles, such as carbon particles.

  17. MA HEAT Loan Overview

    Broader source: Energy.gov [DOE]

    Presents information on the success of Massachusetts's HEAT loan offerings and how the financing tool is funded.

  18. Solar heat receiver

    DOE Patents [OSTI]

    Hunt, Arlon J. (Oakland, CA); Hansen, Leif J. (Berkeley, CA); Evans, David B. (Orinda, CA)

    1985-01-01

    A receiver for converting solar energy to heat a gas to temperatures from 700.degree.-900.degree. C. The receiver is formed to minimize impingement of radiation on the walls and to provide maximum heating at and near the entry of the gas exit. Also, the receiver is formed to provide controlled movement of the gas to be heated to minimize wall temperatures. The receiver is designed for use with gas containing fine heat absorbing particles, such as carbon particles.

  19. Cold Climates Heat Pump Design Optimization

    SciTech Connect (OSTI)

    Abdelaziz, Omar [ORNL] [ORNL; Shen, Bo [ORNL] [ORNL

    2012-01-01

    Heat pumps provide an efficient heating method; however they suffer from sever capacity and performance degradation at low ambient conditions. This has deterred market penetration in cold climates. There is a continuing effort to find an efficient air source cold climate heat pump that maintains acceptable capacity and performance at low ambient conditions. Systematic optimization techniques provide a reliable approach for the design of such systems. This paper presents a step-by-step approach for the design optimization of cold climate heat pumps. We first start by describing the optimization problem: objective function, constraints, and design space. Then we illustrate how to perform this design optimization using an open source publically available optimization toolbox. The response of the heat pump design was evaluated using a validated component based vapor compression model. This model was treated as a black box model within the optimization framework. Optimum designs for different system configurations are presented. These optimum results were further analyzed to understand the performance tradeoff and selection criteria. The paper ends with a discussion on the use of systematic optimization for the cold climate heat pump design.

  20. Liquid heat capacity lasers

    DOE Patents [OSTI]

    Comaskey, Brian J. (Walnut Creek, CA); Scheibner, Karl F. (Tracy, CA); Ault, Earl R. (Livermore, CA)

    2007-05-01

    The heat capacity laser concept is extended to systems in which the heat capacity lasing media is a liquid. The laser active liquid is circulated from a reservoir (where the bulk of the media and hence waste heat resides) through a channel so configured for both optical pumping of the media for gain and for light amplification from the resulting gain.

  1. Pioneering Heat Pump Project

    Broader source: Energy.gov [DOE]

    Project objectives: To install and monitor an innovative WaterFurnace geothermal system that is technologically advanced and evolving; To generate hot water heating from a heat pump that uses non-ozone depleting refrigerant CO2. To demonstrate the energy efficiency of this system ground source heat pump system.

  2. Heat Transfer Guest Editorial

    E-Print Network [OSTI]

    Kandlikar, Satish

    Journal of Heat Transfer Guest Editorial We are indeed delighted in bringing out this special issue was showcased in diverse areas such as traditional heat and mass transfer, lab-on-chip, sensors, biomedical applica- tions, micromixers, fuel cells, and microdevices. Selected papers in the field of heat transfer

  3. Model-Based Functional Performance Testing of AHU in Kista Entre 

    E-Print Network [OSTI]

    Carling, P.; Isakson, P.

    2004-01-01

    A seasonal functional performance test based on detailed system simulation together with intensive trending is used to commission a large AHU in the office building, Kista Entré, Sweden....

  4. A corrosive resistant heat exchanger

    DOE Patents [OSTI]

    Richlen, S.L.

    1987-08-10

    A corrosive and erosive resistant heat exchanger which recovers heat from a contaminated heat stream. The heat exchanger utilizes a boundary layer of innocuous gas, which is continuously replenished, to protect the heat exchanger surface from the hot contaminated gas. The innocuous gas is pumped through ducts or perforations in the heat exchanger wall. Heat from the heat stream is transferred by radiation to the heat exchanger wall. Heat is removed from the outer heat exchanger wall by a heat recovery medium. 3 figs., 3 tabs.

  5. Heat recovery in building envelopes

    E-Print Network [OSTI]

    Walker, Iain S.; Sherman, Max H.

    2003-01-01

    2003). Infiltration heat recovery – ASHRAE Research ProjectModel for Infiltration Heat Recovery, Proc. 21 st AnnualN ATIONAL L ABORATORY Heat Recovery in Building Envelopes

  6. Heat Recovery in Building Envelopes

    E-Print Network [OSTI]

    Sherman, Max H.; Walker, Iain S.

    2001-01-01

    Model For Infiltration Heat Recovery. Proceedings 21st AivcLBNL 47329 HEAT RECOVERY IN BUILDING ENVELOPES Max H.contribution because of heat recovery within the building

  7. Heat recovery in building envelopes

    E-Print Network [OSTI]

    Walker, Iain S.; Sherman, Max H.

    2003-01-01

    2003). Infiltration heat recovery – ASHRAE Research ProjectModel for Infiltration Heat Recovery, Proc. 21 st AnnualWalker, I.S. (2001). "Heat Recovery in Building Envelopes".

  8. Field Monitoring Protocol: Mini-Split Heat Pumps

    SciTech Connect (OSTI)

    Dane Christensen; Xia Fang; Jeff Tomerlin; Jon Winkler

    2011-03-01

    This Building America program report provides a detailed method for accurately measuring and monitoring performance of a residential mini-split heat pump, which will be used in high-performance retrofit applications.

  9. Field Monitoring Protocol: Mini-Split Heat Pumps

    SciTech Connect (OSTI)

    Christensen, D.; Fang, X.; Tomerlin, J.; Winkler, J.; Hancock, E.

    2011-03-01

    The report provides a detailed method for accurately measuring and monitoring performance of a residential Mini-Split Heat Pump. It will be used in high-performance retrofit applications, and as part of DOE's Building America residential research program.

  10. SEASONAL THERMAL ENERGY STORAGE IN AQUIFERS-MATHEMATICAL MODELING STUDIES IN 1979

    E-Print Network [OSTI]

    Tsang, Chin Fu

    2013-01-01

    LBL~l0208 SEASONAL THERMAL ENERGY STORAGE IN AQUIFERS~began working on seasonal thermal energy storage in aquifers

  11. Chemical heat pump

    DOE Patents [OSTI]

    Greiner, Leonard (2750-C Segerstrom Ave., Santa Ana, CA 92704)

    1980-01-01

    A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to facilitate installation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer. The heat pump part of the system heats or cools a house or other structure through a combination of evaporation and absorption or, conversely, condensation and desorption, in a pair of containers. A set of automatic controls change the system for operation during winter and summer months and for daytime and nighttime operation to satisfactorily heat and cool a house during an entire year. The absorber chamber is subjected to solar heating during regeneration cycles and is covered by one or more layers of glass or other transparent material. Daytime home air used for heating the home is passed at appropriate flow rates between the absorber container and the first transparent cover layer in heat transfer relationship in a manner that greatly reduce eddies and resultant heat loss from the absorbant surface to ambient atmosphere.

  12. Heat Transfer Fluids for Solar Water Heating Systems | Department...

    Broader source: Energy.gov (indexed) [DOE]

    Illustration of a solar water heater. Illustration of a solar water heater. Heat-transfer fluids carry heat through solar collectors and a heat exchanger to the heat storage tanks...

  13. Absorption heat pump system

    DOE Patents [OSTI]

    Grossman, Gershon (Oak Ridge, TN); Perez-Blanco, Horacio (Knoxville, TN)

    1984-01-01

    An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

  14. Seasonal demand and supply analysis of turkeys 

    E-Print Network [OSTI]

    Blomo, Vito James

    1972-01-01

    (percentage) responsiveness of price to changes (usually one percent) in quantity. Assuming a linear demand function, flexibility is shown to be less than one in the upper half of the function, equal to one (unitary) at the midpoint, and greater than one...SEASONAL DEMAND AND SUPPLY ANALYSIS OF TURKEYS A Thesis by VITO JAMES BLOMO Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE May 1972 Ma)or Sub...

  15. Replacing Resistance Heating with Mini-Split Heat Pumps, Sharon, Connecticut (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2014-05-01

    Mini-split heat pumps can provide space heating and cooling in many climates and are relatively affordable. These and other features make them potentially suitable for retrofitting into multifamily buildings in cold climates to replace electric resistance heating or other outmoded heating systems. This report investigates the suitability of mini-split heat pumps for multifamily retrofits. Various technical and regulatory barriers are discussed and modeling was performed to compare long-term costs of substituting mini-splits for a variety of other heating and cooling options. A number of utility programs have retrofit mini-splits in both single family and multifamily residences. Two such multifamily programs are discussed in detail.

  16. Heat pump apparatus

    DOE Patents [OSTI]

    Nelson, Paul A. (Wheaton, IL); Horowitz, Jeffrey S. (Woodridge, IL)

    1983-01-01

    A heat pump apparatus including a compact arrangement of individual tubular reactors containing hydride-dehydride beds in opposite end sections, each pair of beds in each reactor being operable by sequential and coordinated treatment with a plurality of heat transfer fluids in a plurality of processing stages, and first and second valves located adjacent the reactor end sections with rotatable members having multiple ports and associated portions for separating the hydride beds at each of the end sections into groups and for simultaneously directing a plurality of heat transfer fluids to the different groups. As heat is being generated by a group of beds, others are being regenerated so that heat is continuously available for space heating. As each of the processing stages is completed for a hydride bed or group of beds, each valve member is rotated causing the heat transfer fluid for the heat processing stage to be directed to that bed or group of beds. Each of the end sections are arranged to form a closed perimeter and the valve member may be rotated repeatedly about the perimeter to provide a continuous operation. Both valves are driven by a common motor to provide a coordinated treatment of beds in the same reactors. The heat pump apparatus is particularly suitable for the utilization of thermal energy supplied by solar collectors and concentrators but may be used with any source of heat, including a source of low-grade heat.

  17. Evaluating the Performance and Economics of Transpired Solar Collectors for Commercial Applications: Preprint

    SciTech Connect (OSTI)

    Kozubal, E.; Deru, M.; Slayzak, S.; Norton, P.; Barker, G.; McClendon, J,

    2008-07-01

    Using transpired solar collectors to preheat ventilation air has recently become recognized as an economic alternative for integrating renewable energy into commercial buildings in heating climates. The collectors have relatively low installed costs and operate on simple principles. Theory and performance testing have shown that solar collection efficiency can exceed 70% of incident solar. However, implementation and current absorber designs have adversely affected the efficiency and associated economics from this initial analysis. The National Renewable Energy Laboratory has actively studied this technology and monitored performance at several installations. A calibrated model that uses typical meteorological weather data to determine absorber plate efficiency resulted from this work. With this model, an economic analysis across heating climates was done to show the effects of collector size, tilt, azimuth, and absorptivity. The analysis relates the internal rate of return of a system based on the cost of the installed absorber area. In general, colder and higher latitude climates return a higher rate of return because the heating season extends into months with good solar resource.

  18. Active microchannel heat exchanger

    DOE Patents [OSTI]

    Tonkovich, Anna Lee Y. (Pasco, WA) [Pasco, WA; Roberts, Gary L. (West Richland, WA) [West Richland, WA; Call, Charles J. (Pasco, WA) [Pasco, WA; Wegeng, Robert S. (Richland, WA) [Richland, WA; Wang, Yong (Richland, WA) [Richland, WA

    2001-01-01

    The present invention is an active microchannel heat exchanger with an active heat source and with microchannel architecture. The microchannel heat exchanger has (a) an exothermic reaction chamber; (b) an exhaust chamber; and (c) a heat exchanger chamber in thermal contact with the exhaust chamber, wherein (d) heat from the exothermic reaction chamber is convected by an exothermic reaction exhaust through the exhaust chamber and by conduction through a containment wall to the working fluid in the heat exchanger chamber thereby raising a temperature of the working fluid. The invention is particularly useful as a liquid fuel vaporizer and/or a steam generator for fuel cell power systems, and as a heat source for sustaining endothermic chemical reactions and initiating exothermic reactions.

  19. NBSBR 84-2867 Test Procedures for Rating

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    the heating mode. Both air-source and ground water source absorption heat pumps are considered, as well as air, air conditioners, and heat pump units. Key words: Central air conditioners; central heating equipment; heat pumps; heating seasonal performance; cooling seasonal performance; rating procedure; seasonal cost

  20. Computer simulation of heat transfer from earth sheltered structures: A comparison of varying levels of earth sheltering in five different climates

    SciTech Connect (OSTI)

    Meixel, G.D.

    1980-12-01

    Computer predictions of the HVAC energy consumption for single story office buildings with varying levels of earth-sheltering indicate that significant energy savings are possible with fully-bermed and bermed-and-covered configurations. As shown by the computer analysis, increased earth-sheltering reduced uncontrolled infiltration; improved the thermal performance of the walls, roof, and floor; and located the windows for more favorable passive solar gain. For example, 50% reductions in winter heating energy for Boston occurred with the fully-bermed and the bermed-and-covered configuration. Earth-sheltering also significantly reduced the predicted peak heating and cooling loads. The Boston heating season showed the most favorable response with the fully-covered office building having a peak heating load only 35% of that for the above-grade configuration. In Manila the predicted peak cooling load for the fully-covered building is 63% of that for the slab-on-grade configuration. Details of the impact of earth-sheltering on the single story office building model are presented for each of the five locations.

  1. Radiant Heating | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    across the room. When radiant heating is located in the floor, it is often called radiant floor heating or simply floor heating. Radiant heating has a number of advantages. It is...

  2. Home Performance Contractor Pro Forma | Department of Energy

    Office of Environmental Management (EM)

    Performance Contractor Pro Forma More Documents & Publications Home Performance Contractor Pro Forma Energy Intensity Indicators Data Commercial Air Conditioners and Heat Pumps...

  3. NSF/DOE Thermoelectric Partnership: High-Performance Thermoelectric...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    High-Performance Thermoelectric Devices Based on Abundant Silicide Materials for Vehicle Waste Heat Recovery NSFDOE Thermoelectric Partnership: High-Performance Thermoelectric...

  4. PERFORMANCE EFFECTS OF AIR VELOCITY PROFILES IN

    E-Print Network [OSTI]

    PERFORMANCE EFFECTS OF AIR VELOCITY PROFILES IN A RESIDENTIAL HEAT PUMP By NATHAN ANDREW WEBER PROFILES IN A RESIDENTIAL HEAT PUMP Thesis Approved: _______________________________________ Thesis Advisor the air speed transducer mount and the Plexiglas model of the heat pump. Ipseng Iu and myself worked side

  5. The seasons, global temperature, and precession

    SciTech Connect (OSTI)

    Thompson, D.J.

    1995-12-31

    Analysis of instrumental temperature records beginning in 1659 shows that in much of the world the dominant frequency of the seasons is one cycle per anomalistic year (the time from perihelion to perihelion, 265.25964 days), not one cycle per tropical year (the time from equinox to equinox, 265.24220 days), and that the timing of the annual temperature cycle is controlled by perihelion. The assumption that the seasons were timed by the equinoxes has caused many statistical analyses of climate data to be badly biased. Coherence between changes in the amplitude of the annual cycle and those in the average temperature show that between 1854 and 1922 there were small temperature variations, probable of solar origin. Since 1922, the phase of the Northern Hemisphere coherence between these quantities switched from 0{degrees} to 180{degrees} and implies that solar variability cannot be the sole cause of the increasing temperature over the last century. About 1940, the phase patterns of the previous 300 years began to change and now appear to be changing at an unprecendented rate. The average change in phase is not coherent with the logarithm of atmospheric CO{sub 2} concentration.

  6. SEASONAL CHANGES IN TITAN'S SURFACE TEMPERATURES

    SciTech Connect (OSTI)

    Jennings, D. E.; Cottini, V.; Nixon, C. A.; Flasar, F. M.; Kunde, V. G.; Samuelson, R. E.; Romani, P. N.; Hesman, B. E. [Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Carlson, R. C.; Gorius, N. J. P. [Department of Physics, Catholic University of America, Washington, DC 20064 (United States); Coustenis, A. [LESIA, Observatoire de Paris-Meudon, 92195 Meudon Cedex (France); Tokano, T., E-mail: donald.e.jennings@nasa.gov [Institut fuer Geophysik und Meteorologie, Universitaet zu Koeln, Albertus-Magnus-Platz, 50923 Koeln (Germany)

    2011-08-10

    Seasonal changes in Titan's surface brightness temperatures have been observed by Cassini in the thermal infrared. The Composite Infrared Spectrometer measured surface radiances at 19 {mu}m in two time periods: one in late northern winter (LNW; L{sub s} = 335 deg.) and another centered on northern spring equinox (NSE; L{sub s} = 0 deg.). In both periods we constructed pole-to-pole maps of zonally averaged brightness temperatures corrected for effects of the atmosphere. Between LNW and NSE a shift occurred in the temperature distribution, characterized by a warming of {approx}0.5 K in the north and a cooling by about the same amount in the south. At equinox the polar surface temperatures were both near 91 K and the equator was at 93.4 K. We measured a seasonal lag of {Delta}L{sub S} {approx} 9{sup 0} in the meridional surface temperature distribution, consistent with the post-equinox results of Voyager 1 as well as with predictions from general circulation modeling. A slightly elevated temperature is observed at 65{sup 0} S in the relatively cloud-free zone between the mid-latitude and southern cloud regions.

  7. The seasons, global temperature, and precession

    SciTech Connect (OSTI)

    Thomson, D.J. [AT& T Bell Labs, Murray Hill, NJ (United States)

    1995-04-07

    Analysis of instrumental temperature records beginning in 1659 shows that in much of the world the dominant frequency of the seasons is one cycle per anomalistic year (the time from perihelion to perihelion, 365.25964 days), not one cycle per tropical year (the time from equinox to equinox, 365.24220 days), and that the timing of the annual temperature cycle is controlled by perihelion. The assumption that the seasons were timed by the equinoxes has caused many statistical analyses of climate data to be badly biased. Coherence between changes in the amplitude of the annual cycle and those in the average temperature show that between 1854 and 1922 there were small temperature variations, probably of solar origin. Since 1922, the phase of the Northern Hemisphere coherence between these quantities switched from 0{degrees} to 180{degrees} and implies that solar variability cannot be the sole cause of the increasing temperature over the last century. About 1940, the phase patterns of the previous 300 years began to change and now appear to be changing at an unprecedented rate. The average change in phase is now coherent with the logarithm of atmospheric CO{sub 2} concentration. 80 refs., 13 figs.

  8. A GUIDE TO FUEL PERFORMANCE

    SciTech Connect (OSTI)

    LITZKE,W.

    2004-08-01

    Heating oil, as its name implies, is intended for end use heating consumption as its primary application. But its identity in reference name and actual chemical properties may vary based on a number of factors. By name, heating oil is sometimes referred to as gas oil, diesel, No. 2 distillate (middle distillate), or light heating oil. Kerosene, also used as a burner fuel, is a No. 1 distillate. Due to the higher heat content and competitive price in most markets, No. 2 heating oil is primarily used in modern, pressure-atomized burners. Using No. 1 oil for heating has the advantages of better cold-flow properties, lower emissions, and better storage properties. Because it is not nearly as abundant in supply, it is often markedly more expensive than No. 2 heating oil. Given the advanced, low-firing rate burners in use today, the objective is for the fuel to be compatible and achieve combustion performance at the highest achievable efficiency of the heating systems--with minimal service requirements. Among the Oil heat industry's top priorities are improving reliability and reducing service costs associated with fuel performance. Poor fuel quality, fuel degradation, and contamination can cause burner shut-downs resulting in ''no-heat'' calls. Many of these unscheduled service calls are preventable with routine inspection of the fuel and the tank. This manual focuses on No. 2 heating oil--its performance, properties, sampling and testing. Its purpose is to provide the marketer, service manager and technician with the proper guidelines for inspecting the product, maintaining good fuel quality, and the best practices for proper storage. Up-to-date information is also provided on commercially available fuel additives, their appropriate use and limitations.

  9. Technical evaluation of a solar heating system having conventional hydronic solar collectors and a radiant panel slab. Final report

    SciTech Connect (OSTI)

    Starr, R.J.

    1984-04-01

    A simple innovative solar heating design (Solar Option One) using conventional hydronic solar collectors and a radiant panel slab was constructed. An objective of hybrid solar design is to combine the relative advantages of active and passive design approaches while minimizing their respective disadvantages. A test house using the Solar Option One heating system was experimentally monitored to determine its energy based performance during the 1982-83 heating season. The test residence is located in Lyndonville, Vermont, an area which has a characteristically cold and cloudy climate. The two story residence has a floor area of about 1400 square feet and is constructed on a 720 square foot 5.5 inch thick floor slab. A 24 inch packed gravel bed is located beneath the slab and the slab-gravel bed is insulated by two inches of polystyrene insulation. The test building is of frame construction and uses insulation levels which have become commonplace throughout the country. The structure would not fall into the superinsulated category but was tightly constructed so as to have a low infiltration level. The building is sun-tempered in that windows were concentrated somewhat on the South side and all but avoided on the North. A solar greenhouse on the South side of the building was closed off from the structure permanently throughout the testing so as to better observe the solar heating invention without confounding variables. The monitoring equipment generated an internal gain of about 17,000 BTUs per day, roughly the equivalent of occupancy by two persons. A full description of the experimental testing program is given. System efficiency and performance are reported.

  10. Patches in the polar ionosphere: UT and seasonal dependence

    SciTech Connect (OSTI)

    Sojka, J.J.; Bowline, M.D.; Schunk, R.W. [Utah State Univ., Logan, UT (United States)] [Utah State Univ., Logan, UT (United States)

    1994-08-01

    The seasonal and UT dependencies of patches in the polar ionosphere are simulated using the Utah State University time dependent ionospheric model (TDIM). Patch formation is achieved by changing the plasma convection pattern in response to temporal changes in the interplanetary magnetic field (IMF) B{sub y} component during periods of southward IMF. This mechanism redirects the plasma flow from the dayside high-density region, which is the source of the tongue of ionization (TOI) density feature, through the throat and leads to patches, rather than a continuous TOI. The model predicts that the patches are absent at winter solstice (northern hemisphere) between 0800 and 1200 UT and that they have their largest seasonal intensity at winter solstice between 2000 and 2400 UT. Between winter solstice and equinox, patches are strong and present all day. Patches are present in summer as well, although their intensity is only tens of percent above the background density. These winter-to-equinox findings are also shown to be consistent with observations. The model was also used to predict times at which patch observations could be performed to determine the contributions from other patch mechanisms. This observational window is {+-} 20 days about winter solstice between 0800 and 1200 UT in the northern hemisphere. In this observational window the TOI is either absent or reduced to a very low density. Hence the time dependent electric field mechanism considered in this study does not produce patches, and if they are observed, then they must be due to some other mechanism. 32 refs., 10 figs.

  11. Optimization of Heat Exchangers

    SciTech Connect (OSTI)

    Ivan Catton

    2010-10-01

    The objective of this research is to develop tools to design and optimize heat exchangers (HE) and compact heat exchangers (CHE) for intermediate loop heat transport systems found in the very high temperature reator (VHTR) and other Generation IV designs by addressing heat transfer surface augmentation and conjugate modeling. To optimize heat exchanger, a fast running model must be created that will allow for multiple designs to be compared quickly. To model a heat exchanger, volume averaging theory, VAT, is used. VAT allows for the conservation of mass, momentum and energy to be solved for point by point in a 3 dimensional computer model of a heat exchanger. The end product of this project is a computer code that can predict an optimal configuration for a heat exchanger given only a few constraints (input fluids, size, cost, etc.). As VAT computer code can be used to model characteristics )pumping power, temperatures, and cost) of heat exchangers more quickly than traditional CFD or experiment, optimization of every geometric parameter simultaneously can be made. Using design of experiment, DOE and genetric algorithms, GE, to optimize the results of the computer code will improve heat exchanger disign.

  12. Heat pump system

    DOE Patents [OSTI]

    Swenson, Paul F. (Shaker Heights, OH); Moore, Paul B. (Fedhaven, FL)

    1983-01-01

    An air heating and cooling system for a building includes an expansion type refrigeration circuit and a vapor power circuit. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The vapor power circuit includes two heat exchangers, one of which is disposed in series air flow relationship with the indoor refrigeration circuit heat exchanger and the other of which is disposed in series air flow relationship with the outdoor refrigeration circuit heat exchanger. Fans powered by electricity generated by a vapor power circuit alternator circulate indoor air through the two indoor heat exchangers and circulate outside air through the two outdoor heat exchangers. The system is assembled as a single roof top unit, with a vapor power generator and turbine and compressor thermally insulated from the heat exchangers, and with the indoor heat exchangers thermally insulated from the outdoor heat exchangers.

  13. Heat pump system

    DOE Patents [OSTI]

    Swenson, Paul F.; Moore, Paul B.

    1983-06-21

    An air heating and cooling system for a building includes an expansion type refrigeration circuit and a vapor power circuit. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The vapor power circuit includes two heat exchangers, one of which is disposed in series air flow relationship with the indoor refrigeration circuit heat exchanger and the other of which is disposed in series air flow relationship with the outdoor refrigeration circuit heat exchanger. Fans powered by electricity generated by a vapor power circuit alternator circulate indoor air through the two indoor heat exchangers and circulate outside air through the two outdoor heat exchangers. The system is assembled as a single roof top unit, with a vapor power generator and turbine and compressor thermally insulated from the heat exchangers, and with the indoor heat exchangers thermally insulated from the outdoor heat exchangers.

  14. Policies supporting Heat Pump Technologies

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    Policies supporting Heat Pump Technologies in Canada IEA Heat Pump Workshop London, UK November 13 in the world, with an average of 16,995 kilowatt-hours per annum. #12;Canada's Context for Heat Pumps Impacts avenues: Ground source heat pumps for cold climates (heating and cooling) Reversible air source heat

  15. Operational limit of closed loop pulsating heat pipes Honghai Yang a,*, S. Khandekar b

    E-Print Network [OSTI]

    Khandekar, Sameer

    Operational limit of closed loop pulsating heat pipes Honghai Yang a,*, S. Khandekar b , M. Groll c an experimental study on the operational limitation of closed loop pulsating heat pipes (CLPHPs), which consist pipes; Performance limit; Dry-out 1. Introduction Pulsating heat pipes (PHPs) or oscillating heat pipes

  16. A Semi-Empirical Model for Porous Media Heat Exchanger Design Richard A. Wirtz1

    E-Print Network [OSTI]

    Wirtz, Richard A.

    A Semi-Empirical Model for Porous Media Heat Exchanger Design Richard A. Wirtz1 Mechanical-dimensional temperature Introduction Compact heat exchangers invariably incorporate heat transfer augmentation technology matrix at the fluid-solid interface of a compact heat exchanger will also enhance performance

  17. Degrees of freedom and optimal operation of simple heat pump cycles

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Degrees of freedom and optimal operation of simple heat pump cycles Jørgen Bauck Jensen and Sigurd in the opposite direction, the "heat pump", has recently become pop- ular. These two applications have also merged of performance for a heating cycle (heat pump) and a cooling cycle (refrigerator, A/C) are defined as COPh = Qh

  18. Control and optimal operation of simple heat pump cycles Jrgen B. Jensen and Sigurd Skogestad

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Control and optimal operation of simple heat pump cycles Jørgen B. Jensen and Sigurd Skogestad cycle. Keywords: Operation, heat pump cycle, cyclic process, charge, self-optimizing control 1. The coefficients of performance for a heating cycle (heat pump) and a cooling cycle (re- frigerator, A

  19. Fluidized bed heat treating system

    DOE Patents [OSTI]

    Ripley, Edward B; Pfennigwerth, Glenn L

    2014-05-06

    Systems for heat treating materials are presented. The systems typically involve a fluidized bed that contains granulated heat treating material. In some embodiments a fluid, such as an inert gas, is flowed through the granulated heat treating medium, which homogenizes the temperature of the heat treating medium. In some embodiments the fluid may be heated in a heating vessel and flowed into the process chamber where the fluid is then flowed through the granulated heat treating medium. In some embodiments the heat treating material may be liquid or granulated heat treating material and the heat treating material may be circulated through a heating vessel into a process chamber where the heat treating material contacts the material to be heat treated. Microwave energy may be used to provide the source of heat for heat treating systems.

  20. Natural gas inventories heading to record levels at start of winter heating season

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet) Wyoming Dry Natural GasNatural GasEIARegionalMethodology forNYMEXUsedNatural gas

  1. Water-heating dehumidifier

    DOE Patents [OSTI]

    Tomlinson, John J. (Knoxville, TN)

    2006-04-18

    A water-heating dehumidifier includes a refrigerant loop including a compressor, at least one condenser, an expansion device and an evaporator including an evaporator fan. The condenser includes a water inlet and a water outlet for flowing water therethrough or proximate thereto, or is affixed to the tank or immersed into the tank to effect water heating without flowing water. The immersed condenser design includes a self-insulated capillary tube expansion device for simplicity and high efficiency. In a water heating mode air is drawn by the evaporator fan across the evaporator to produce cooled and dehumidified air and heat taken from the air is absorbed by the refrigerant at the evaporator and is pumped to the condenser, where water is heated. When the tank of water heater is full of hot water or a humidistat set point is reached, the water-heating dehumidifier can switch to run as a dehumidifier.

  2. Seasonal changes in Titan's meteorology E. P. Turtle,1

    E-Print Network [OSTI]

    during the approach to the northern spring equinox in August 2009. Recent observations have shown, Titan's seasons have progressed from southern summer to early southern autumn, and changes

  3. BPA revises policy for managing seasonal power oversupply

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    policy-for-managing-seasonal-power-oversupply Sign In About | Careers | Contact | Investors | bpa.gov Search News & Us Expand News & Us Projects & Initiatives Expand Projects...

  4. Sandia Energy - Understanding Seasonal Effects of WEC Operation...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Understanding Seasonal Effects of WEC Operation using the SNL-SWAN Wave Model Application Home Renewable Energy Energy Water Power News News & Events Systems Analysis Computational...

  5. Horizontal Heat Exchanger Design and Analysis for Passive Heat Removal Systems

    SciTech Connect (OSTI)

    Vierow, Karen

    2005-08-29

    This report describes a three-year project to investigate the major factors of horizontal heat exchanger performance in passive containment heat removal from a light water reactor following a design basis accident LOCA (Loss of Coolant Accident). The heat exchanger studied in this work may be used in advanced and innovative reactors, in which passive heat removal systems are adopted to improve safety and reliability The application of horizontal tube-bundle condensers to passive containment heat removal is new. In order to show the feasibility of horizontal heat exchangers for passive containment cooling, the following aspects were investigated: 1. the condensation heat transfer characteristics when the incoming fluid contains noncondensable gases 2. the effectiveness of condensate draining in the horizontal orientation 3. the conditions that may lead to unstable condenser operation or highly degraded performance 4. multi-tube behavior with the associated secondary-side effects This project consisted of two experimental investigations and analytical model development for incorporation into industry safety codes such as TRAC and RELAP. A physical understanding of the flow and heat transfer phenomena was obtained and reflected in the analysis models. Two gradute students (one funded by the program) and seven undergraduate students obtained research experience as a part of this program.

  6. Enhanced two phase flow in heat transfer systems

    DOE Patents [OSTI]

    Tegrotenhuis, Ward E; Humble, Paul H; Lavender, Curt A; Caldwell, Dustin D

    2013-12-03

    A family of structures and designs for use in devices such as heat exchangers so as to allow for enhanced performance in heat exchangers smaller and lighter weight than other existing devices. These structures provide flow paths for liquid and vapor and are generally open. In some embodiments of the invention, these structures can also provide secondary heat transfer as well. In an evaporate heat exchanger, the inclusion of these structures and devices enhance the heat transfer coefficient of the evaporation phase change process with comparable or lower pressure drop.

  7. Heat storage duration

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1981-01-01

    Both the amount and duration of heat storage in massive elements of a passive building are investigated. Data taken for one full winter in the Balcomb solar home are analyzed with the aid of sub-system simulation models. Heat storage duration is tallied into one-day intervals. Heat storage location is discussed and related to overall energy flows. The results are interpreted and conclusions drawn.

  8. SMALL PARTICLE HEAT EXCHANGERS

    E-Print Network [OSTI]

    Hunt, A.J.

    2011-01-01

    by half, the solar collection efficiency will still be insolar thermal electric power program rests on the efficiency,efficiency heat storage systems. This type of hybrid, solar-

  9. Mechanical Compression Heat Pumps 

    E-Print Network [OSTI]

    Apaloo, T. L.; Kawamura, K.; Matsuda, J.

    1986-01-01

    of the compressors which constitute the heart and soul of the system. It will also provide a quick survey of the available types of compressors for heat pumping and some of the industrial processes where simultaneous heating and cooling proceed along parallel..., the real challenge comes process environment, or even for comfort HEAT PUMP APPLICATIONS INPU~ AND OUTPUT UTIUnES (HEAT SOUlCE) (ME0U.4) (API't1CATION) CoofIng, Dehumldilication. L.- -J ~Ing. Hot ...,tolel SIJr-lpIy Chilled ....,oter. Hoi waler...

  10. Waste Heat Recovery

    Office of Environmental Management (EM)

    DRAFT - PRE-DECISIONAL - DRAFT 1 Waste Heat Recovery 1 Technology Assessment 2 Contents 3 1. Introduction to the TechnologySystem ......

  11. Photovoltaic roof heat flux

    E-Print Network [OSTI]

    Samady, Mezhgan Frishta

    2011-01-01

    Effect of building integrated photovoltaics on microclimateof a building's integrated-photovoltaics on heating a n dgaps for building- integrated photovoltaics, Solar Energy

  12. Heat and mass exchanger

    DOE Patents [OSTI]

    Lowenstein, Andrew (Princeton, NJ); Sibilia, Marc J. (Princeton, NJ); Miller, Jeffrey A. (Hopewell, NJ); Tonon, Thomas (Princeton, NJ)

    2011-06-28

    A mass and heat exchanger includes at least one first substrate with a surface for supporting a continuous flow of a liquid thereon that either absorbs, desorbs, evaporates or condenses one or more gaseous species from or to a surrounding gas; and at least one second substrate operatively associated with the first substrate. The second substrate includes a surface for supporting the continuous flow of the liquid thereon and is adapted to carry a heat exchange fluid therethrough, wherein heat transfer occurs between the liquid and the heat exchange fluid.

  13. Heat and mass exchanger

    DOE Patents [OSTI]

    Lowenstein, Andrew (Princeton, NJ); Sibilia, Marc J. (Princeton, NJ); Miller, Jeffrey A. (Hopewell, NJ); Tonon, Thomas (Princeton, NJ)

    2007-09-18

    A mass and heat exchanger includes at least one first substrate with a surface for supporting a continuous flow of a liquid thereon that either absorbs, desorbs, evaporates or condenses one or more gaseous species from or to a surrounding gas; and at least one second substrate operatively associated with the first substrate. The second substrate includes a surface for supporting the continuous flow of the liquid thereon and is adapted to carry a heat exchange fluid therethrough, wherein heat transfer occurs between the liquid and the heat exchange fluid.

  14. HEATS: Thermal Energy Storage

    SciTech Connect (OSTI)

    2012-01-01

    HEATS Project: The 15 projects that make up ARPA-E’s HEATS program, short for “High Energy Advanced Thermal Storage,” seek to develop revolutionary, cost-effective ways to store thermal energy. HEATS focuses on 3 specific areas: 1) developing high-temperature solar thermal energy storage capable of cost-effectively delivering electricity around the clock and thermal energy storage for nuclear power plants capable of cost-effectively meeting peak demand, 2) creating synthetic fuel efficiently from sunlight by converting sunlight into heat, and 3) using thermal energy storage to improve the driving range of electric vehicles (EVs) and also enable thermal management of internal combustion engine vehicles.

  15. Influence of seasonality and vegetation type on suburban microclimates

    E-Print Network [OSTI]

    Peters, Emily B.; McFadden, Joseph P.

    2010-01-01

    tools to reduce urban heat islands and home energy use (ground cover and urban heat island of Nanjing, China. BuildEG (1994) Cooling urban heat islands with sustainable

  16. 1 Copyright 2013 by ASME Proceedings of the ASME 2013 Summer Heat Transfer Conference

    E-Print Network [OSTI]

    Bahrami, Majid

    Storage (TES) systems; ii) power electronics of solar/wind/tidal energy conversion systems; iii) power in the characteristics of heat transfer equipment. Generally, processes such as start-up, shut- down, power surge subjected to daily variation, seasonal variation, and weather conditions. As such, the power electronics

  17. Enhancement of Presynaptic Performance in Transgenic Drosophila Overexpressing

    E-Print Network [OSTI]

    Robertson, Meldrum

    would provide stability to neural circuits otherwise susceptible to heat stress. Synapse 44:8­14, 2002Enhancement of Presynaptic Performance in Transgenic Drosophila Overexpressing Heat Shock Protein; quanta ABSTRACT Prior heat shock confers protection to Drosophila synapses during sub- sequent heat

  18. Performance Assessment Report Domain CHP System

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    Performance Assessment Report for the Domain CHP System November 2005 By Burns & McDonnell Engineering #12;Domain CHP System Performance Assessment Report for the Packaged Cooling, Heating and Power

  19. Computational model of miniature pulsating heat pipes.

    SciTech Connect (OSTI)

    Martinez, Mario J.; Givler, Richard C.

    2013-01-01

    The modeling work described herein represents Sandia National Laboratories (SNL) portion of a collaborative three-year project with Northrop Grumman Electronic Systems (NGES) and the University of Missouri to develop an advanced, thermal ground-plane (TGP), which is a device, of planar configuration, that delivers heat from a source to an ambient environment with high efficiency. Work at all three institutions was funded by DARPA/MTO; Sandia was funded under DARPA/MTO project number 015070924. This is the final report on this project for SNL. This report presents a numerical model of a pulsating heat pipe, a device employing a two phase (liquid and its vapor) working fluid confined in a closed loop channel etched/milled into a serpentine configuration in a solid metal plate. The device delivers heat from an evaporator (hot zone) to a condenser (cold zone). This new model includes key physical processes important to the operation of flat plate pulsating heat pipes (e.g. dynamic bubble nucleation, evaporation and condensation), together with conjugate heat transfer with the solid portion of the device. The model qualitatively and quantitatively predicts performance characteristics and metrics, which was demonstrated by favorable comparisons with experimental results on similar configurations. Application of the model also corroborated many previous performance observations with respect to key parameters such as heat load, fill ratio and orientation.

  20. BIODIESEL BLENDS IN SPACE HEATING EQUIPMENT.

    SciTech Connect (OSTI)

    KRISHNA,C.R.

    2001-12-01

    Biodiesel is a diesel-like fuel that is derived from processing vegetable oils from various sources, such as soy oil, rapeseed or canola oil, and also waste vegetable oils resulting from cooking use. Brookhaven National laboratory initiated an evaluation of the performance of blends of biodiesel and home heating oil in space heating applications under the sponsorship of the Department of Energy (DOE) through the National Renewable Energy Laboratory (NREL). This report is a result of this work performed in the laboratory. A number of blends of varying amounts of a biodiesel in home heating fuel were tested in both a residential heating system and a commercial size boiler. The results demonstrate that blends of biodiesel and heating oil can be used with few or no modifications to the equipment or operating practices in space heating. The results also showed that there were environmental benefits from the biodiesel addition in terms of reductions in smoke and in Nitrogen Oxides (NOx). The latter result was particularly surprising and of course welcome, in view of the previous results in diesel engines where no changes had been seen. Residential size combustion equipment is presently not subject to NOx regulation. If reductions in NOx similar to those observed here hold up in larger size (commercial and industrial) boilers, a significant increase in the use of biodiesel-like fuel blends could become possible.

  1. Heat pipes and use of heat pipes in furnace exhaust

    DOE Patents [OSTI]

    Polcyn, Adam D. (Pittsburgh, PA)

    2010-12-28

    An array of a plurality of heat pipe are mounted in spaced relationship to one another with the hot end of the heat pipes in a heated environment, e.g. the exhaust flue of a furnace, and the cold end outside the furnace. Heat conversion equipment is connected to the cold end of the heat pipes.

  2. 4.A. HEAT FLOW 119 4.A. Heat flow

    E-Print Network [OSTI]

    Hunter, John K.

    denote the temperature, g : R the rate per unit volume at which heat sources create energy inside the body, and q : Rn the heat flux. That is, the rate per unit area at which heat energy diffuses across of energy implies that for any smooth open set the heat flux out of is equal to the rate at which heat

  3. Proceedings of Heat Transfer 2003: ASME Summer Heat Transfer Conference

    E-Print Network [OSTI]

    Kandlikar, Satish

    Proceedings of Heat Transfer 2003: ASME Summer Heat Transfer Conference Las Vegas, Nevada, USA July 21-23, 2003 HT2003-47449 HEAT TRANSFER FROM A MOVING AND EVAPORATING MENISCUS ON A HEATED SURFACE meniscus with complete evaporation of water without any meniscus break-up. The experimental heat transfer

  4. Heat Integrate Heat Engines in Process Plants 

    E-Print Network [OSTI]

    Hindmarsh, E.; Boland, D.; Townsend, D. W.

    1986-01-01

    -06-75 Proceedings from the Eighth Annual Industrial Energy Technology Conference, Houston, TX, June 17-19, 1986 I I APPROPRIATE/INAPPROPRIATE INTEGRATION OF HEiT PUMPS, engine transfers h'eat across the' process; pinch.'" . . :i".p., J The insights...

  5. Microchannel heat sink assembly

    DOE Patents [OSTI]

    Bonde, W.L.; Contolini, R.J.

    1992-03-24

    The present invention provides a microchannel heat sink with a thermal range from cryogenic temperatures to several hundred degrees centigrade. The heat sink can be used with a variety of fluids, such as cryogenic or corrosive fluids, and can be operated at a high pressure. The heat sink comprises a microchannel layer preferably formed of silicon, and a manifold layer preferably formed of glass. The manifold layer comprises an inlet groove and outlet groove which define an inlet manifold and an outlet manifold. The inlet manifold delivers coolant to the inlet section of the microchannels, and the outlet manifold receives coolant from the outlet section of the microchannels. In one embodiment, the manifold layer comprises an inlet hole extending through the manifold layer to the inlet manifold, and an outlet hole extending through the manifold layer to the outlet manifold. Coolant is supplied to the heat sink through a conduit assembly connected to the heat sink. A resilient seal, such as a gasket or an O-ring, is disposed between the conduit and the hole in the heat sink in order to provide a watertight seal. In other embodiments, the conduit assembly may comprise a metal tube which is connected to the heat sink by a soft solder. In still other embodiments, the heat sink may comprise inlet and outlet nipples. The present invention has application in supercomputers, integrated circuits and other electronic devices, and is suitable for cooling materials to superconducting temperatures. 13 figs.

  6. Microchannel heat sink assembly

    DOE Patents [OSTI]

    Bonde, Wayne L. (Livermore, CA); Contolini, Robert J. (Pleasanton, CA)

    1992-01-01

    The present invention provides a microchannel heat sink with a thermal range from cryogenic temperatures to several hundred degrees centigrade. The heat sink can be used with a variety of fluids, such as cryogenic or corrosive fluids, and can be operated at a high pressure. The heat sink comprises a microchannel layer preferably formed of silicon, and a manifold layer preferably formed of glass. The manifold layer comprises an inlet groove and outlet groove which define an inlet manifold and an outlet manifold. The inlet manifold delivers coolant to the inlet section of the microchannels, and the outlet manifold receives coolant from the outlet section of the microchannels. In one embodiment, the manifold layer comprises an inlet hole extending through the manifold layer to the inlet manifold, and an outlet hole extending through the manifold layer to the outlet manifold. Coolant is supplied to the heat sink through a conduit assembly connected to the heat sink. A resilient seal, such as a gasket or an O-ring, is disposed between the conduit and the hole in the heat sink in order to provide a watetight seal. In other embodiments, the conduit assembly may comprise a metal tube which is connected to the heat sink by a soft solder. In still other embodiments, the heat sink may comprise inlet and outlet nipples. The present invention has application in supercomputers, integrated circuits and other electronic devices, and is suitable for cooling materials to superconducting temperatures.

  7. Chemical heat pump

    DOE Patents [OSTI]

    Greiner, Leonard (2853-A Hickory Pl., Costa Mesa, CA 92626)

    1984-01-01

    A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure, as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to facilitate intallation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer.

  8. Chemical heat pump

    DOE Patents [OSTI]

    Greiner, Leonard (2853-A Hickory Pl., Costa Mesa, CA 92626)

    1984-01-01

    A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure, as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to facilitate installation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer.

  9. Chemical heat pump

    DOE Patents [OSTI]

    Greiner, Leonard (2853-A Hickory Pl., Costa Mesa, CA 92626)

    1984-01-01

    A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure, as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to faciliate installation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer.

  10. Chemical heat pump

    DOE Patents [OSTI]

    Greiner, Leonard (2853-A Hickory Pl., Costa Mesa, CA 92626)

    1981-01-01

    A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure, as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to facilitate installation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer.

  11. The Assessment and Calibration of Ensemble Seasonal Forecasts of Equatorial Pacific Ocean Temperature and the Predictability of Uncertainty

    E-Print Network [OSTI]

    Jewson, S; Hagedorn, Rolf; Jewson, Stephen; Doblas-Reyes, Francisco; Hagedorn, Renate

    2003-01-01

    We evaluate the performance of two 44 year ensemble seasonal hindcast time series for the Nino3 index produced as part of the DEMETER project. We show that the ensemble mean carries useful information out to six months. The ensemble spread, however, only carries useful information out to four months in one of the models, and two months in the other.

  12. Knudsen heat capacity

    SciTech Connect (OSTI)

    Babac, Gulru; Reese, Jason M.

    2014-05-15

    We present a “Knudsen heat capacity” as a more appropriate and useful fluid property in micro/nanoscale gas systems than the constant pressure heat capacity. At these scales, different fluid processes come to the fore that are not normally observed at the macroscale. For thermodynamic analyses that include these Knudsen processes, using the Knudsen heat capacity can be more effective and physical. We calculate this heat capacity theoretically for non-ideal monatomic and diatomic gases, in particular, helium, nitrogen, and hydrogen. The quantum modification for para and ortho hydrogen is also considered. We numerically model the Knudsen heat capacity using molecular dynamics simulations for the considered gases, and compare these results with the theoretical ones.

  13. Improved solar heating systems

    DOE Patents [OSTI]

    Schreyer, J.M.; Dorsey, G.F.

    1980-05-16

    An improved solar heating system is described in which the incident radiation of the sun is absorbed on collector panels, transferred to a storage unit and then distributed as heat for a building and the like. The improvement is obtained by utilizing a storage unit comprising separate compartments containing an array of materials having different melting points ranging from 75 to 180/sup 0/F. The materials in the storage system are melted in accordance with the amount of heat absorbed from the sun and then transferred to the storage system. An efficient low volume storage system is provided by utilizing the latent heat of fusion of the materials as they change states in storing ad releasing heat for distribution.

  14. Solar heating system

    DOE Patents [OSTI]

    Schreyer, James M. (Oak Ridge, TN); Dorsey, George F. (Concord, TN)

    1982-01-01

    An improved solar heating system in which the incident radiation of the sun is absorbed on collector panels, transferred to a storage unit and then distributed as heat for a building and the like. The improvement is obtained by utilizing a storage unit comprising separate compartments containing an array of materials having different melting points ranging from 75.degree. to 180.degree. F. The materials in the storage system are melted in accordance with the amount of heat absorbed from the sun and then transferred to the storage system. An efficient low volume storage system is provided by utilizing the latent heat of fusion of the materials as they change states in storing and releasing heat for distribution.

  15. Seasonal mass balance gradients in Norway L. A. Rasmussen1

    E-Print Network [OSTI]

    Rasmussen, L.A.

    16 Aug 05 Seasonal mass balance gradients in Norway L. A. Rasmussen1 and L. M. Andreassen2 1 Norwegian Water Resources and Energy Directorate (NVE) P. O. Box 5091 Majorstua, N-0301 Oslo, Norway in Norway exists in their profiles of both seasonal balances, winter bw(z) and summer bs(z). Unlike many

  16. A global picture of the seasonal persistence of stratospheric ozone

    E-Print Network [OSTI]

    Wirosoetisno, Djoko

    A global picture of the seasonal persistence of stratospheric ozone anomalies Article Published persistence of stratospheric ozone anomalies. Journal of Geophysical Research, 115. D18119. ISSN 0148-0227 doi global picture of the seasonal persistence of stratospheric ozone anomalies S. Tegtmeier,1,2 V. E

  17. Environmental Patterns Associated with Active and Inactive Caribbean Hurricane Seasons

    E-Print Network [OSTI]

    Environmental Patterns Associated with Active and Inactive Caribbean Hurricane Seasons MARK R. JURY of hurricanes passing through the Caribbean in the 1950­2005 period reveals that seasons with more intense hurricanes occur with the onset of Pacific La Nin~a events and when Atlantic SSTs west of Africa are above

  18. NOAA 2015 Atlantic Hurricane Season Outlook Dr. Gerry Bell

    E-Print Network [OSTI]

    Chen, Tsuhan

    NOAA 2015 Atlantic Hurricane Season Outlook Dr. Gerry Bell Lead Seasonal Forecaster Climate Prediction Center NOAA/ NWS/ NCEP Collaboration With National Hurricane Center/ NOAA/ NWS/ NCEP Hurricane Research Division/ NOAA/ OAR/ AOML/ HRD www.cpc.ncep.noaa.gov/products/hurricane #12;Outline 1. Features

  19. Exergy Analysis and Operational Efficiency of a Horizontal Ground Source Heat Pump System Operated in a Low-Energy Test House under Simulated Occupancy Conditions

    SciTech Connect (OSTI)

    Ally, Moonis Raza [ORNL; Baxter, Van D [ORNL; Munk, Jeffrey D [ORNL; Gehl, Anthony C [ORNL

    2012-01-01

    This paper presents data, analyses, measures of performance, and conclusions for a ground-source heat pump (GSHP) providing space conditioning to a 345m2 house whose envelope is made of structural insulated panels (SIP). The entire thermal load of this SIP house with RSI-3.7 (RUS-21) walls, triple pane windows with a U-factor of 1.64 W/m2 K (0.29 Btu/h ft2 oF) and solar heat gain coefficient (SHGC) of 0.25, a roof assembly with overall thermal resistance of about RSI-8.8 (RUS-50) and low leakage rates of 0.74 ACH at 50Pa was satisfied with a 2.16-Ton (7.56 kW) GSHP unit consuming negligible (9.83kWh) auxiliary heat during peak winter season. The highest and lowest heating COP achieved was 4.90 (October) and 3.44 (February), respectively. The highest and lowest cooling COP achieved was 6.09 (April) and 3.88 (August). These COPs are calculated on the basis of the total power input (including duct, ground loop, and control power losses ). The second Law (Exergy) analysis provides deep insight into how systemic inefficiencies are distributed among the various GSHP components. Opportunities for design and further performance improvements are identified. Through Exergy analysis we provide a true measure of how closely actual performance approaches the ideal, and it unequivocally identifies, better than energy analysis does, the sources and causes of lost work, the root cause of system inefficiencies.

  20. Heat Exchangers for Solar Water Heating Systems | Department...

    Broader source: Energy.gov (indexed) [DOE]

    from iStockphoto.com Image of a heat exchanger. | Photo from iStockphoto.com Solar water heating systems use heat exchangers to transfer solar energy absorbed in solar...