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Sample records for hfc refrigerant mixtures

  1. TWO-PHASE FLOW OF TWO HFC REFRIGERANT MIXTURES THROUGH SHORT-TUBE ORIFICES

    EPA Science Inventory

    The report gives results of an experimental investigation to develop an acceptable flow model for short tube orifice expansion devices used in heat pumps. The refrigerants investigated were two hydrofluorocarbon (HFC) mixtures considered hydrochlorofluorocarbon (HCFC)-22 replacem...

  2. Foaming characteristics of HFC refrigerants

    SciTech Connect

    Goswami, D.Y.; Shah, D.O.; Jotshi, C.K.; Bhagwat, S.; Leung, M.; Gregory, A.S.

    1997-06-01

    A detailed study was conducted at the University of Florida to experimentally determine the absorption and desorption rates of HFC and blended refrigerants in polyolester lubricant and to define the characteristics of the foam formed when the refrigerant leaves the refrigerant/lubricant mixture after being exposed to a pressure drop. The alternative refrigerants examined include HFC-32 (R-32), R-125, R-134a, and R-143a. Also examined were blended refrigerants R-404A, R407C, and R410A. These refrigerants were tested with two ISO 68 polyolesters (Witco SL68 and ICI RL 68H). To establish baseline results, refrigerants R-12 and R-22 were tested with mineral oils ISO32 (3GS) and ISO 68 (4GS).

  3. The Performance Evaluation of Vapor Compression Heat Pump System Using HFC Alternative Refrigerant Mixtures

    NASA Astrophysics Data System (ADS)

    Taira, Shigeharu; Yazima, Ryuzaburo; Tarutani, Isamu; Koyama, Shigeru

    This paper deals with an experimental study on the performance evaluation of heat pump systems using HFC alternative refrigerants. The tested heat pump systems are modified from the R22 use to alternative refrigerants. Refrigerant mixtures of R410A, R407C. R32/125 and R32/134a are tested. where R410A and R407C launched into global market recently. Pure refrigerants of R22, R32, R125 and R134a are also tested. The experimental results of alternative refrigerants are evaluated in comparison with the result of R22, and the following are confirmed : (1) the performance of R32 is the highest. (2) adding R125 to R32 and R32/134a results into the deterioration of the performance, (3) the use of counter flow-like heat exchangers for a zeotropic refrigerant mixtures are effective, and (4) in case of R410A. the modification of the compressor to fit operating pressure heightens the performance. The effects of the performance of components on the COP are also analyzed based on the measured thermodynamic states at both ends of components in the system. Then, it is clarified that the most effective factor is irreversibility of compressors and the following is the pressure drop in low pressure side including the evaporator and the suction pipe.

  4. Formation Conditions of Clathrates Between HFC Alternative Refrigerants and Water

    NASA Astrophysics Data System (ADS)

    Akiya, T.; Shimazaki, T.; Oowa, M.; Matsuo, M.; Yoshida, Y.

    1999-11-01

    There are two promising candidates as alternative refrigerants for air-conditioners and heat pumps. The first is R407C, which is composed of HFC-32 (23 mass%), HFC-125 (25 mass%), and HFC-134a (52 mass%). The second is R410A, which is composed of HFC-32 (50 mass%) and HFC-125 (50 mass%). In this study, formation conditions of clathrate compounds between water and HFC alternative refrigerants such as HFC-32, HFC-125, HFC-134a, and their mixtures, R407C and R410A, were investigated. Phase diagrams of clathrates of these HFC alternative refrigerants and their mixtures were determined. From the phase diagrams, the critical decomposition temperature and the critical decomposition pressure were determined. The relationship between the critical decomposition points for the clathrates of HFC-32, HFC-125, HFC-134a, R410A, and R407C were studied. It is found that R407C and R410A form clathrate compounds with water under the evaporating temperature condition in the refrigeration cycle of air-conditioners and heat pumps.

  5. Two-Phase Flow of Two HFC Refrigerant Mixtures Through Short Tube Orifices, Draft Final Report 

    E-print Network

    Payne, W. V.; O'Neal, D. L.

    1994-01-01

    The present study presents data for flow of two refrigerant mixtures through short tube orifices. The two mixtures were R3211251134a (23%/25%/52% on a mass percentage basis) and R321125 (50%/50%). The following presents ...

  6. THERMODYNAMIC PROPERTIES OF SELECTED HFC REFRIGERANTS

    EPA Science Inventory

    Hydrofluorocarbon (HFC) refrigerants are possible alternatives to replace ozone-depleting chlorofluorocarbon and hydrochlorofluorocarbon (HCFC) refrigerants. The flammability of a proposed new refrigerant is a major consideration in assessing its utility for a particular applicat...

  7. Performance of a Small-sized Refrigeration Comperssor Using HFC-134a

    NASA Astrophysics Data System (ADS)

    Kohsokabe, Hirokatsu; Endoh, Kazuhiro; Kunugi, Yoshifumi; Iwata, Hiroshi; Hata, Hiroaki; Fujiwara, Mitsuru

    When CFC-12 is replaced by HFC-134a in small-sized refrigeration compressors for domestic refrigerators, the coefficient of performance (COP) of rotary compressors decreases. On the other hand,the COP of reciprocating compressors is almost the same as that of CFC-12. The main causes of rotary compressor performance decrease are higher viscosity of HFC-134a/oil mixture,and greater re-expansion loss of gas in clearance volume. The performance is improved by optimizing the oil viscosity through directly measuring viscosity of HFC-134a/oil mixture inside the compressor chamber with a viscosity sensor. Difference of oil type has small influence on the COP.

  8. Parametric performance analysis of OTEC system using HFC32/HFC134a mixtures

    SciTech Connect

    Uehara, Haruo; Ikegami, Yasuyuki

    1995-11-01

    Parametric performance analysis is performed on an Ocean Thermal Energy Conversion (OTEC) system using HFC32/HFC134a mixtures as working fluid. The analyzed OTEC system uses the Kalina cycle. The parameters in the performance analysis consist of the warm sea water inlet temperature, the cold sea water inlet temperature, the heat transfer performance of the evaporator, condenser and regenerator, the turbine inlet pressure, the turbine inlet temperature, the molar fraction of HFC32. Effects of these various parameters on the efficiency of the Kalina cycle using HFC32/HFC134a mixtures are clarified by using this analysis, and compared with calculation results using ammonia/water mixtures as working fluid. The thermal efficiency of OTEC system using the Kalina cycle can reach up to about 5 percent with an inlet warm sea water temperature of 28 C and an inlet cold sea water temperature of 4 C.

  9. PERFORMANCE OF CHLORINE-FREE BINARY ZEOTROPIC REFRIGERANT MIXTURES IN A HEAT PUMP

    EPA Science Inventory

    The report gives results of a study that uses a simulation model and an experimental heat pump apparatus with counterflow heat exchangers to show that two hydrofluorocarbon (HFC) refrigerant mixtures, HFC-32/-152a and HFC-32/-134a, may be considered to be replacements for hydroch...

  10. HFC-134A and HCFC-22 supermarket refrigeration demonstration and laboratory testing. Phase I. Final report

    SciTech Connect

    1996-04-01

    Aspen Systems and a team of nineteen agencies and industry participants conducted a series of tests to determine the performance of HFC-134a, HCFC-22, and CFC-502 for supermarket application. This effort constitutes the first phase of a larger project aimed at carrying out both laboratory and demonstration tests of the most viable HFC refrigerants and the refrigerants they replace. The results of the Phase I effort are presented in the present report. The second phase of the project has also been completed. It centered on testing all viable HFC replacement refrigerants for CFC-502. These were HFC-507, HFC-404A, and HFC-407A. The latter results are published in the Phase II report for this project. As part of Phase I, a refrigeration rack utilizing a horizontal open drive screw compressor was constructed in our laboratory. This refrigeration rack is a duplicate of one we have installed in a supermarket in Clifton Park, NY.

  11. Global emissions of refrigerants HCFC-22 and HFC-134a: Unforeseen seasonal contributions

    E-print Network

    Xiang, Bin

    HCFC-22 (CHClF[subscript 2]) and HFC-134a (CH[subscript 2]FCF[subscript 3]) are two major gases currently used worldwide in domestic and commercial refrigeration and air conditioning. HCFC-22 contributes to stratospheric ...

  12. Simulation of vapor-compression refrigeration cycles using HFC134a and CFC12

    SciTech Connect

    Chen, Q.; Prasad, R.C.

    1999-05-01

    A performance comparison analysis of vapor-compression refrigeration systems using refrigerant HFC134a and CFC12 is presented. The analysis is based on computer simulation of actual cycles rather than the ideal cycles. The simulation models for HFC134a and CFC12 are developed on the basis of fluid properties and thermo-hydraulic characteristics obtained from available experimental data and/or correlations. Using the simulation model thus developed, system performance with HFC134a and CFC12 are examined. A comparison of the performance of HFC134a and CFC12 is presented using COP (and compressor power) as a criterion for the same cooling load. Results indicate that the COP for HFC134a is slightly (about 3%) lower than that for a CFC12 system. This means that the power requirement for a HFC134a system is slightly higher than that for CFC12 system for an identical cooling requirement. A comparison of these two systems from a thermodynamic point of view is also presented using exergy loss as a performance evaluation criterion. These results indicate that the HFC134a system is only slightly inferior to the CFC 12 systems due to a higher (about 3%) exergy loss with HFC134a.

  13. MODELING AND DESIGN STUDY USING HFC-236EA AS AN ALTERNATIVE REFRIGERANT IN A CENTRIFUGAL COMPRESSOR

    EPA Science Inventory

    The report gives results of an investigation of the operation of a centrifugal compressor--part of a chlorofluorocarbon (CFC)-114 chiller installation--with the new refrigerant hydrofluorocarbon (HFC)-236ea, a proposed alternative to CFC-114. A large set of CFC-236ea operating da...

  14. Global Emissions of Refrigerants HCFC-22 and HFC-134a: Unforeseen Seasonal Contributions

    NASA Astrophysics Data System (ADS)

    Xiang, B.; Patra, P. K.; Montzka, S. A.; Miller, S. M.; Elkins, J. W.; Moore, F.; Atlas, E. L.; Miller, B. R.; Prinn, R. G.; Wofsy, S. C.

    2014-12-01

    HCFC-22 (CHClF2) and HFC-134a (CH2FCF3) are two major gases currently used worldwide in domestic and commercial refrigeration and air conditioning. HCFC-22 contributes to stratospheric ozone depletion and both species are potent greenhouse gases, and their global emissions continue to rise at the present. In this work, we study aircraft based in-situ observations of HCFC-22 and HFC-134a over the Pacific Ocean in a three-year span (HIaper Pole-to-Pole Observation of carbon cycle and greenhouse gases study, HIPPO 2009-2011) and combine these data with long-term observations from global surface sites (NOAA and AGAGE networks). We find a steady increase in global annual emissions of HCFC-22 and HFC-134a for the past two decades (on average 3% and 4% per year, respectively). Emissions of HFC-134a since 2000 are consistently higher, with 60% more in recent years (2009-2011), compared to the United Nations Framework Convention on Climate Change (UNFCCC) inventory. Using both HIPPO and surface data, we quantify and verify enhanced summertime emissions of HFC-134a and HCFC-22 that are about three times those in the wintertime. This unforeseen large seasonal contribution indicates unaccounted mechanisms controlling refrigerant gas emissions, missing in the existing inventory estimates. Possible mechanisms for greater refrigerant leakages in the summer are: 1) higher vapor pressure in the sealed compartment of the system at summer high temperatures (saturated vapor pressure is ~ 3 times at 303 K compared to that at 273 K for both species), and 2) more frequent use of refrigeration and air conditioners in the summer (vapor pressure in the compressor line is higher when in use than not in use). Our results suggest that the engineering of the refrigeration and air conditioning systems can greatly influence the release of these two species to the atmosphere.

  15. Global emissions of refrigerants HCFC-22 and HFC-134a: unforeseen seasonal contributions.

    PubMed

    Xiang, Bin; Patra, Prabir K; Montzka, Stephen A; Miller, Scot M; Elkins, James W; Moore, Fred L; Atlas, Elliot L; Miller, Ben R; Weiss, Ray F; Prinn, Ronald G; Wofsy, Steven C

    2014-12-01

    HCFC-22 (CHClF2) and HFC-134a (CH2FCF3) are two major gases currently used worldwide in domestic and commercial refrigeration and air conditioning. HCFC-22 contributes to stratospheric ozone depletion, and both species are potent greenhouse gases. In this work, we study in situ observations of HCFC-22 and HFC-134a taken from research aircraft over the Pacific Ocean in a 3-y span [HIaper-Pole-to-Pole Observations (HIPPO) 2009-2011] and combine these data with long-term ground observations from global surface sites [National Oceanic and Atmospheric Administration (NOAA) and Advanced Global Atmospheric Gases Experiment (AGAGE) networks]. We find the global annual emissions of HCFC-22 and HFC-134a have increased substantially over the past two decades. Emissions of HFC-134a are consistently higher compared with the United Nations Framework Convention on Climate Change (UNFCCC) inventory since 2000, by 60% more in recent years (2009-2012). Apart from these decadal emission constraints, we also quantify recent seasonal emission patterns showing that summertime emissions of HCFC-22 and HFC-134a are two to three times higher than wintertime emissions. This unforeseen large seasonal variation indicates that unaccounted mechanisms controlling refrigerant gas emissions are missing in the existing inventory estimates. Possible mechanisms enhancing refrigerant losses in summer are (i) higher vapor pressure in the sealed compartment of the system at summer high temperatures and (ii) more frequent use and service of refrigerators and air conditioners in summer months. Our results suggest that engineering (e.g., better temperature/vibration-resistant system sealing and new system design of more compact/efficient components) and regulatory (e.g., reinforcing system service regulations) steps to improve containment of these gases from working devices could effectively reduce their release to the atmosphere. PMID:25422438

  16. Global emissions of refrigerants HCFC-22 and HFC-134a: Unforeseen seasonal contributions

    PubMed Central

    Xiang, Bin; Montzka, Stephen A.; Miller, Scot M.; Elkins, James W.; Moore, Fred L.; Atlas, Elliot L.; Miller, Ben R.; Weiss, Ray F.; Prinn, Ronald G.; Wofsy, Steven C.

    2014-01-01

    HCFC-22 (CHClF2) and HFC-134a (CH2FCF3) are two major gases currently used worldwide in domestic and commercial refrigeration and air conditioning. HCFC-22 contributes to stratospheric ozone depletion, and both species are potent greenhouse gases. In this work, we study in situ observations of HCFC-22 and HFC-134a taken from research aircraft over the Pacific Ocean in a 3-y span [HIaper-Pole-to-Pole Observations (HIPPO) 2009–2011] and combine these data with long-term ground observations from global surface sites [National Oceanic and Atmospheric Administration (NOAA) and Advanced Global Atmospheric Gases Experiment (AGAGE) networks]. We find the global annual emissions of HCFC-22 and HFC-134a have increased substantially over the past two decades. Emissions of HFC-134a are consistently higher compared with the United Nations Framework Convention on Climate Change (UNFCCC) inventory since 2000, by 60% more in recent years (2009–2012). Apart from these decadal emission constraints, we also quantify recent seasonal emission patterns showing that summertime emissions of HCFC-22 and HFC-134a are two to three times higher than wintertime emissions. This unforeseen large seasonal variation indicates that unaccounted mechanisms controlling refrigerant gas emissions are missing in the existing inventory estimates. Possible mechanisms enhancing refrigerant losses in summer are (i) higher vapor pressure in the sealed compartment of the system at summer high temperatures and (ii) more frequent use and service of refrigerators and air conditioners in summer months. Our results suggest that engineering (e.g., better temperature/vibration-resistant system sealing and new system design of more compact/efficient components) and regulatory (e.g., reinforcing system service regulations) steps to improve containment of these gases from working devices could effectively reduce their release to the atmosphere. PMID:25422438

  17. Liquid viscosities and densities of HFC-134a + glycol mixtures

    SciTech Connect

    Kumagai, A.; Mochida, H.; Takahashi, S. )

    1993-01-01

    Liquid viscosity and density of six binary mixtures of HFC-134a with glycols [ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol (400), and polypropylene glycol (2000)] have been measured in the temperature range from 273 to 333 K. The viscosity was measured by a rolling-ball viscometer calibrated with standard liquids of viscosities and densities (JS5, JS10, JS20, and JS50). The density was measured with a glass pycnometer. The uncertainties of the measurements were estimated to be less than 3.4% for viscosity and 0.04% for density, respectively. An equation is given to represent the obtained viscosity values as a function of weight fraction and temperature.

  18. Elastohydrodynamic Lubrication with Polyolester Lubricants and HFC Refrigerants, Final Report, Volume 2

    SciTech Connect

    Gunsel, Selda; Pozebanchuk, Michael

    1999-04-01

    Lubrication properties of refrigeration lubricants were investigated in high pressure nonconforming contacts under different conditions of temperature, rolling speed, and refrigerant concentration. The program was based upon the recognition that the lubrication regime in refrigeration compressors is generally elastohydrodynamic or hydrodynamic, as determined by the operating conditions of the compressor and the properties of the lubricant. Depending on the compressor design, elastohydrodynamic lubrication conditions exist in many rolling and sliding elements of refrigeration compressors such as roller element bearings, gears, and rotors. The formation of an elastohydrodynamic film separating rubbing surfaces is important in preventing the wear and failure of compressor elements. It is, therefore, important to predict the elastohydrodynamic (EHD) performance of lubricants under realistic tribocontact renditions. This is, however, difficult as the lubricant properties that control film formation are critically dependent upon pressure and shear, and cannot be evaluated using conventional laboratory instruments. In this study, the elastohydrodynamic behavior of refrigeration lubricants with and without the presence of refrigerants was investigated using the ultrathin film EHD interferometry technique. This technique enables very thin films, down to less than 5 nm, to be measured accurately within an EHD contact under realistic conditions of temperature, shear, and pressure. The technique was adapted to the study of lubricant refrigerant mixtures. Film thickness measurements were obtained on refrigeration lubricants as a function of speed, temperature, and refrigerant concentration. The effects of lubricant viscosity, temperature, rolling speed, and refrigerant concentration on EHD film formation were investigated. From the film thickness measurements, effective pressure-viscosity coefficients were calculated. The lubricants studied in this project included two naphthenic mineral oils (NMO), four polyolesters (POE), and two polyvinyl ether (PVE) fluids. These fluids represented viscosity grades of ISO 32 and ISO 68 and are shown in a table. Refrigerants studied included R-22, R-134a, and R-410A. Film thickness measurements were conducted at 23 C, 45 C, and 65 C with refrigerant concentrations ranging from zero to 60% by weight.

  19. EVALUATION OF PERFORMANCE AND COMPOSITION SHIFT OF ZEOTROPIC MIXTURES IN A LORENZ-MEUTZNER REFRIGERATOR/FREEZER

    EPA Science Inventory

    Results from previous testing of this refrigerator/freezer (R/F) using a 750 Btu/hr compressor and several zeotrophic mixtures revealed a performance enhancement up to 16 percent above that of HFC-134a. In the study presented in this paper, the Lorenz-Meutzner (LM) R/F equipped ...

  20. 40 CFR Appendix D to Subpart B of... - SAE J2810 Standard for Recovery Only Equipment for HFC-134a Refrigerant

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...the appropriate ARI 700 Standard or allow for recycling of the recovered refrigerant to SAE J2788...SAE J2788HFC-134a (R-134a) Recovery/Recycling Equipment and Recovery/Recycling/Recharging for Mobile...

  1. 40 CFR Appendix D to Subpart B of... - SAE J2810 Standard for Recovery Only Equipment for HFC-134a Refrigerant

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...the appropriate ARI 700 Standard or allow for recycling of the recovered refrigerant to SAE J2788...SAE J2788HFC-134a (R-134a) Recovery/Recycling Equipment and Recovery/Recycling/Recharging for Mobile...

  2. 40 CFR Appendix D to Subpart B of... - SAE J2810 Standard for Recovery Only Equipment for HFC-134a Refrigerant

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...the appropriate ARI 700 Standard or allow for recycling of the recovered refrigerant to SAE J2788...SAE J2788HFC-134a (R-134a) Recovery/Recycling Equipment and Recovery/Recycling/Recharging for Mobile...

  3. 40 CFR Appendix D to Subpart B of... - SAE J2810 Standard for Recovery Only Equipment for HFC-134a Refrigerant

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...the appropriate ARI 700 Standard or allow for recycling of the recovered refrigerant to SAE J2788...SAE J2788HFC-134a (R-134a) Recovery/Recycling Equipment and Recovery/Recycling/Recharging for Mobile...

  4. 40 CFR Appendix D to Subpart B of... - SAE J2810 Standard for Recovery Only Equipment for HFC-134a Refrigerant

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...the appropriate ARI 700 Standard or allow for recycling of the recovered refrigerant to SAE J2788...SAE J2788HFC-134a (R-134a) Recovery/Recycling Equipment and Recovery/Recycling/Recharging for Mobile...

  5. PERFORMANCE OF A TWO-CYCLE REFRIGERATOR/FREEZER USING HFC REFRIGERANTS

    EPA Science Inventory

    A two-cycle 18 ft3 (0.51 m3) refrigerator/freezer (R/F) was tested utilizing American National Standards Institute (ANSI)/AHAM (1988) standards for energy consumption testing. A 34.9% energy consumption reduction was realized. This work presents a proven method of reducing the ...

  6. Chemical and thermal stability of refrigerant-lubricant mixtures with metals

    SciTech Connect

    Huttenlocher, D.F.

    1992-07-10

    This report presents completed sealed tube stability test results for the following eight refrigerant/lubricant mixtures: R-22/mineral oil; R-124/alkylbenzene; R-134a/pentaerythritol (PE) ester (mixed acid); R- 134a/PE (branched acid); R-134a/ PE (100 cSt viscosity); R- 142b/alkylbenzene; R-143a/ PE (branched acid); R-152a/alkylbenzene. Partial results are shown for an additional eight refrigerant-lubricant mixtures. Though work is in progress, no data are available at this point in time for the five remaining test mixtures. Reported are: visual observations on aged sealed tubes, gas chromatographic analyses on the vapor phase contents of the tubes, chloride ion contents of HCFC containing mixtures or fluoride ion contents of HFC mixtures, and total acid number values and infrared analysis results for mixtures containing ester lubricants.

  7. Development of New Refrigeration Circuit to Control Refrigerant Mixture Composition

    NASA Astrophysics Data System (ADS)

    Yoshida, Yuji; Suzuki, Sigeo; Nakatani, Kazuo; Mukai, Yuji; Adachi, Masaaki

    The use of refrigerant mixture is an important subject of heat-pump technology and its research and developments have been promoted all over the world. We have tried to apply mixed refrigerants to air-conditioners, and developed an unique technology for efficiently separating and varying the mixing ratio of the refrigerants inside the refrigeration circuit. The mixed fluorinated refrigerants of R22-R13B1 were adapted to increase the heating capacity. Effects of shapes of packings and diameters of column were examined by an experimental apparatus of rectifier only, and a small rectifier with new coiled packings was developed. In the new circuit, the bottom of the rectifier is connected with condenser and evaporator by lines in parallel with expansion device. In the rectifying mode, the lower boiling-point refrigerant is stored in a reservoir connected to the top of the rectifier, and a main circuit is operated with the higher boiling-point refrigerant. Then the heating capacity, the input wattage and the fluid pressure of a heat-pump operating with the separated refrigerants are decreased to a lower level and its energy efficiency was improved through an inspection of the rectifying vapour generation method. The technique of estimating the composition of mixture operating in the circuit was developed, too, and the calculated values almost coincide with the experimetal values.

  8. Phase equilibria of chlorofluorocarbon alternative refrigerant mixtures

    SciTech Connect

    Lee, B.G.; Park, J.Y.; Lim, J.S.; Cho, S.Y.; Park, K.Y.

    1999-03-01

    Isothermal vapor-liquid equilibrium data were determined for binary systems of difluoromethane/1,1,1,2-tetrafluoroethane (HFC-32/HFC-134a), difluoromethane/pentafluoroethane (HFC-32/HFC-125), difluoromethane/1,1,1-trifluoroethane (HFC-32/HFC-143A), and difluoromethane/1,1-difluoroethane (HFC-32/HFC-152a). The vapor and liquid compositions and pressures were measured in a circulation-type apparatus at 303.15 K and 323.15 K. The experimental data were compared with literature results and correlated with the Canahan-Starling-De Santis equation of state within the uncertainty of {+-}1.0%.

  9. Estimated 2017 Refrigerant Emissions of 2,3,3,3-Tetrafluoropropene (HFC-1234yf) in the United States Resulting from Automobile Air Conditioning

    EPA Science Inventory

    In response to recent regulations and concern over climate change, the global automotive community is evaluating alternatives to the current refrigerant used in automobile air conditioning units, 1,1,1,2-tetrafluoroethane, HFC-134a. One potential alternative is 2,3,3,3-tetrafluor...

  10. Chemical and thermal stability of refrigerant-lubricant mixtures with metals. Quarterly report, 1 April 1992--30 June 1992

    SciTech Connect

    Huttenlocher, D.F.

    1992-07-10

    This report presents completed sealed tube stability test results for the following eight refrigerant/lubricant mixtures: R-22/mineral oil; R-124/alkylbenzene; R-134a/pentaerythritol (PE) ester (mixed acid); R- 134a/PE (branched acid); R-134a/ PE (100 cSt viscosity); R- 142b/alkylbenzene; R-143a/ PE (branched acid); R-152a/alkylbenzene. Partial results are shown for an additional eight refrigerant-lubricant mixtures. Though work is in progress, no data are available at this point in time for the five remaining test mixtures. Reported are: visual observations on aged sealed tubes, gas chromatographic analyses on the vapor phase contents of the tubes, chloride ion contents of HCFC containing mixtures or fluoride ion contents of HFC mixtures, and total acid number values and infrared analysis results for mixtures containing ester lubricants.

  11. Elastohydrodynamic Lubrication with Polyolester Lubricants and HFC Refrigerants, Final Report, Volume 1

    SciTech Connect

    Gunsel, Selda; Pozebanchuk, Michael

    1999-04-01

    The objective of this study was to investigate the film formation properties of refrigeration lubricants using the ultrathin film elastohydrodynamic (EHD) interferometry technique and to study the effects of refrigerants on film formation. Film thickness measurements were conducted as a function of lubricant viscosity, speed, temperature, and refrigerant concentration. Based on the EHD film thickness data, effective pressure-viscosity coefficients were calculated for the test fluids at different temperatures and the effects of refrigerants on pressure-viscosity properties were investigated.

  12. Theoretical Analysis of Heat Pump Cycle Characteristics with Pure Refrigerants and Binary Refrigerant Mixtures

    NASA Astrophysics Data System (ADS)

    Kagawa, Noboru; Uematsu, Masahiko; Watanabe, Koichi

    In recent years there has been an increasing interest of the use of nonazeotropic binary mixtures to improve performance in heat pump systems, and to restrict the consumption of chlorofluorocarbon (CFC) refrigerants as internationally agreed-upon in the Montreal Protocol. However, the available knowledge on the thermophysical properties of mixtures is very much limited particularly with respect to quantitative information. In order to systematize cycle performance with Refrigerant 12 (CCl2F2) + Refrigerant 22 (CHClF2) and Refrigerant 22 + Refrigerant 114 (CClF2-CClF2) systems which are technically important halogenated refrigerant mixtures, the heat pump cycle analysis in case of using these mixtures was theoretically studied. It became clear that the maximum coefficients of performance with various pure refrigerants and binary refrigerant mixtures were obtained at the reduced condensing temperature being 0.9 when the same temperature difference between condensing and evaporating temperature was chosen.

  13. Chemical and thermal stability of refrigerant-lubricant mixture with metal

    SciTech Connect

    Huttenlocher, D.F. )

    1992-03-31

    This report presents completed sealed tube stability test results for the R-123/mineral oil mixture and preliminary results for seven of the eighteen contracted refrigerant-lubricant mixtures. The R-123 mixture was tested at 105, 150, and 175{degrees}C. The results obtained indicate that prolonged exposure to temperatures of about 150{degree}C and higher will lead to rapid chemical deterioration of the R-123/mineral oil system. Chlorotrifluoroethane (R-133a) and trifluoroethane (R-143a) have been identified as decomposition products of R-123. Testing at 150 and 175{degrees}C have been completed for the HCFC refrigerants R-22, R-124, and R-142b with either mineral oil or alkylbenzene lubricants. These mixtures were very stable at the indicated temperatures. Testing at a higher temperature level will be necessary to define their upper temperature limits. Similarily, partial test results are available for HFC refrigerants R-32, R-125, R-134a (two esters), and R-143a with pentaerythritol ester lubricants at the 150 and 175{degrees}C temperature levels. Again, all five mixtures were found to be extremely stable at the test temperatures and additional testing will be needed to establish their upper temperature limits.

  14. GAS CHROMATOGRAPHIC RETENTION PARAMETERS DATABASE FOR REFRIGERANT MIXTURE COMPOSITION MANAGEMENT

    EPA Science Inventory

    Composition management of mixed refrigerant systems is a challenging problem in the laboratory, manufacturing facilities, and large refrigeration machinery. Ths issue of composition management is especially critical for the maintenance of machinery that utilizes zeotropic mixture...

  15. REFLEAK: NIST Leak/Recharge Simulation Program for Refrigerant Mixtures

    National Institute of Standards and Technology Data Gateway

    SRD 73 NIST REFLEAK: NIST Leak/Recharge Simulation Program for Refrigerant Mixtures (PC database for purchase)   REFLEAK estimates composition changes of zeotropic mixtures in leak and recharge processes.

  16. Compatibility of lubricant additives with HFC refrigerants and synthetic lubricants. Final report, Part 1

    SciTech Connect

    Cavestri, R.C.

    1997-07-01

    Part one of this research provides manufacturers of components of air-conditioning and refrigeration equipment with a useful list of lubricant additives, sources, functional properties and chemical species. The list in part one is comprised of domestic lubricant additive suppliers and the results of a literature search that was specifically targeted for additives reported to be useful in polyolester chemistry.

  17. Theoretical Analysis of Heat Pump Cycle Characteristics with Pure Refrigerants and Binary Refrigerant Mixtures

    NASA Astrophysics Data System (ADS)

    Kagawa, Noboru; Uematsu, Masahiko; Watanabe, Koichi

    In recent years there has been an increasing interest of the use of nonazeotropic binary mixtures to improve performance in heat pump systems, and to restrict the consumption of chlorofluorocarbon (CFC) refrigerants as internationally agreed-upon in the Montreal Protocol. However, the available knowledge on the thermophysical properties of mixtures is very much limited particularly with respect to quantitative information. In order to examine cycle performance for Refrigerant 12 (CCl2F2) + Refrigerant 22 (CHClF2) and Refrigerant 22 + Refrigerant 114 (CClF2-CClF2) systems which are technically important halogenated refrigerant mixtures, the heat pump cycle analysis in case of using pure Refrigerants 12, 22 and 114 was theoretically carried out in the present paper. For the purpose of systematizing the heat pump cycle characteristics with pure refrigerants, the cycle analysis for Refrigerants 502, 13B1, 152a, 717 (NH3) and 290 (C3H8) was also examined. It became clear that the maximum coefficients of performance with various refrigerants were obtained at the reduced condensing temperature being 0.9 when the same temperature difference between condensing and evaporating temperature was chosen.

  18. COP improvement of refrigerator/freezers, air-conditioners, and heat pumps using nonazeotropic refrigerant mixtures

    NASA Technical Reports Server (NTRS)

    Westra, Douglas G.

    1993-01-01

    With the February, 1992 announcement by President Bush to move the deadline for outlawing CFC (chloro-fluoro-carbon) refrigerants from the year 2000 to the year 1996, the refrigeration and air-conditioning industries have been accelerating their efforts to find alternative refrigerants. Many of the alternative refrigerants being evaluated require synthetic lubricants, are less efficient, and have toxicity problems. One option to developing new, alternative refrigerants is to combine existing non-CFC refrigerants to form a nonazeotropic mixture, with the concentration optimized for the given application so that system COP (Coefficient Of Performance) may be maintained or even improved. This paper will discuss the dilemma that industry is facing regarding CFC phase-out and the problems associated with CFC alternatives presently under development. A definition of nonazeotropic mixtures will be provided, and the characteristics and COP benefits of nonazeotropic refrigerant mixtures will be explained using thermodynamic principles. Limitations and disadvantages of nonazeotropic mixtures will be discussed, and example systems using such mixtures will be reviewed.

  19. Measurement of viscosity, density, and gas solubility of refrigerant blends in selected synthetic lubricants. Final report

    SciTech Connect

    Cavestri, R.C.

    1995-05-15

    The lubricants tested in this project were chosen based on the results of liquid/liquid miscibility tests. EMKARATE RL32S and Emery 2968A were selected. The Vapor Liquid Equilibrium (VLE) viscosity reduction and gas fractionation of each was measured with three different refrigerant blends: (1) R-404A; (2) R-507; and (3) R-407C. In addition, the four single refrigerants that make up the blends, HFC-32, HFC-125, HFC-134a, and HFC-143a, were also measured. Lubricants found to have the lowest liquid/liquid miscibilities had nearly equal viscosity reduction profiles as did the more miscible lubricants. Analytical methodology consisted of maintaining equally both the composition of the head space vapor above the lubricant/refrigerant mixture, and the composition of the liquid blend refrigerant. Blends with large temperature glides were re-evaluated in order to test the concept of head space quality and a vented piston hydraulic cylinder assembly was developed to perform this task. Fluid property data, above critical temperature and pressure conditions, is presented for the two lubricants with HFC-32, HFC-125, HFC-143a refrigerants. This research shows that the lubricant EMKARATE RL32S, which had the lowest (poorest) liquid/liquid miscibilities with the selected refrigerants, also had nearly equal viscosity reduction profiles to the more miscible Emery 2968A lubricant. The analytical methodology consisted of maintaining the composition of the refrigerant gas above the lubricant to be equal in composition to that of the pure liquid refrigerant blend being introduced into the lubricant. Refrigerant blends with large temperature glides were re-evaluated in order to validate the concept of the importance of the composition of the gas over the lubricant. To do perform this task, a special vented piston hydraulic cylinder assembly was developed. Fluid property data is also presented for HFC-32, HFC-125, and HFC-143a above the critical temperature and pressure of each.

  20. EVALUATION OF OZONE-FRIENDLY HYDROFLUOROPROPANE-BASED ZEOTROPIC REFRIGERANT MIXTURES IN A LORENZ-MEUTZNER REFRIGERATOR/FREEZER

    EPA Science Inventory

    The two-evaporator (located in the freezer and fresh food compartments) design of the Lorenz-Meutzner (L-M) refrigerator/freezer (R/F) makes it a leading candidate for use of zeotropic refrigerant mixtures. Zeotrophic mixtures can have significant temperature glides during evapor...

  1. Chemical and thermal stability of refrigerant-lubricant mixture with metal. Materials compatibility and lubricants research on CFC-refrigerant substitutes: Quarterly report, 1 February 1992--31 March 1992

    SciTech Connect

    Huttenlocher, D.F.

    1992-03-31

    This report presents completed sealed tube stability test results for the R-123/mineral oil mixture and preliminary results for seven of the eighteen contracted refrigerant-lubricant mixtures. The R-123 mixture was tested at 105, 150, and 175{degrees}C. The results obtained indicate that prolonged exposure to temperatures of about 150{degree}C and higher will lead to rapid chemical deterioration of the R-123/mineral oil system. Chlorotrifluoroethane (R-133a) and trifluoroethane (R-143a) have been identified as decomposition products of R-123. Testing at 150 and 175{degrees}C have been completed for the HCFC refrigerants R-22, R-124, and R-142b with either mineral oil or alkylbenzene lubricants. These mixtures were very stable at the indicated temperatures. Testing at a higher temperature level will be necessary to define their upper temperature limits. Similarily, partial test results are available for HFC refrigerants R-32, R-125, R-134a (two esters), and R-143a with pentaerythritol ester lubricants at the 150 and 175{degrees}C temperature levels. Again, all five mixtures were found to be extremely stable at the test temperatures and additional testing will be needed to establish their upper temperature limits.

  2. Some Correlations for Saturated-Liquid Density of Refrigerant Mixtures

    NASA Astrophysics Data System (ADS)

    Maezawa, Yukishige; Sato, Haruki; Watanabe, Koichi

    Three methods to correlate and estimate the saturated-1iquid density of refrigerant mixtures are compared and evaluated on the basis of the measurements for five bibary and one ternary mixtures performed by the present authors. The first of them is a method using Peng-Robinson equation (PR-method) proposed originally by Peneloux et al. Since this method dose not require any measurements of the saturated-liquid density of mixture, it is useful for the estimation. However, the applicability of this method to various substances may be restricted. The second is the modified Rackett equation proposed by Spencer and Dannar (mR-method). The temperature functional form of this equation is quite simple, so it is useful to use it as a functional form of the fitting. Unfortunately this method can not be used for strongly non-ideal mixtures. The last one is the Hankinson-Brobst-Thomson equation (HBT-method). This method can provide the most accurate density values among the three methods with two kinds of binary parameters where these binary parameters are introduced by the present authors. In the case that many experimental saturated liquid densities of mixtures are available in the wide range of temperatures, the HBT-method is recommended for the practical use.

  3. SIMULATION OF NON-AZEOTROPIC REFRIGERANT MIXTURES FOR USE IN A DUAL-CIRCUIT REFRIGERATOR/FREEZER WITH COUNTERCURRENT HEAT EXCHANGES

    EPA Science Inventory

    The paper discusses a refrigerator/freezer (RF) system that has two complete and independent refrigeration cycles for the two compartments. It uses a non-azeotropic refrigerant mixture (NARM) in each cycle and countercurrent heat exchangers throughout. This RF is housed in a stan...

  4. TRANSPORT PROPERTY MEASUREMENTS OF HFC-236EA

    EPA Science Inventory

    The report gives results of an evaluation of transport properties of 1, 1, 1, 2, 3, 3-hexafluoropropane (HFC-236ea), with liquid viscosity and thermal conductivity being the two main transport properties of interest. In addition, the specific heat and density of refrigerant/lubri...

  5. TRANSPORT PROPERTY MEASUREMENTS OF HFC-236EA

    EPA Science Inventory

    The report gives results of an evaluation of transport properties of 1,1,1,2,3,3,-hexafluoropropane (HFC-236ea), with liquid viscosity and thermal conductivity being the two main transport properties of interest. In addition, the specific heat and density of refrigerant/lubrican...

  6. 40 CFR Appendix D to Subpart B of... - SAE J2810 Standard for Recovery Only Equipment for HFC-134a Refrigerant

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 700Specifications for Fluorocarbon Refrigerants. 2.1.3CGA Publication Available from Compressed Gas Association... SAE J2788-certified equipment. It is not acceptable that the refrigerant removed from a mobile air... refrigerant recovery to reduce emissions and provide for accurate recharging of mobile air...

  7. 40 CFR Appendix D to Subpart B of... - SAE J2810 Standard for Recovery Only Equipment for HFC-134a Refrigerant

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 700Specifications for Fluorocarbon Refrigerants. 2.1.3CGA Publication Available from Compressed Gas Association... SAE J2788-certified equipment. It is not acceptable that the refrigerant removed from a mobile air... refrigerant recovery to reduce emissions and provide for accurate recharging of mobile air...

  8. FLAME SUPPRESSION AND LUBRICANT INTERACTION OF HYDROCARBON MIXTURES FOR HOUSEHOLD REFRIGERATOR/FREEZERS

    EPA Science Inventory

    The paper discusses the flame suppression and lubricant interaction of hydrocarbon (HC) mixtures for household refrigerator/freezers (R/Fs). The work focuses on blending the minimum amount of a fluoroiodocarbon (FIC) with previously optimized R/F-tested HC mixtures to reduce thei...

  9. FLAME SUPPRESSION AND LUBRICANT INTERACTION OF HYDROCARBON MIXTURES FOR HOUSEHOLD REFRIGERANT/FREEZERS

    EPA Science Inventory

    The paper discusses the flame suppression and lubricant interaction of hydrocarbon (HC) mixtures for household refrigerator/freezers (R/Fs). he work focuses on blending the minimum amount of a fluoroiodocarbon (FIC) with previously optimized R/F-tested HC mixtures to reduce their...

  10. The Effect of Circuiting Arrangement on the Thermal Performance of Refrigeration Mixtures in Tube-and-Fin Condensing Heat Exchangers

    SciTech Connect

    Chen, D.T.; Conklin, J.C.

    1999-03-15

    For the pure or azeotropic refrigerants typically used in present air conditioning and refrigeration applications, the refrigerant changes phase at a constant temperature. Thus, the refrigerant circuiting arrangement such as crossfiow, counterfiow, or cross-counterflow, has no effect on the thermal performance. For zeotropic refrigerant mixtures, however, the phase-change occurs over a temperature range, or "glide", and the refrigerant circuiting arrangement, or flow path through the heat exchanger, can affect the thermal performance of both the heat exchangers as well as the overall efficiency of the vapor compression cooling cycle. The effects of tsvo diflerent circuiting arrangements on the thermal performance of a zeotropic retligerant mixture and an almost azeotropic refrigerant mixture in a four-row cross-countertlow heat exchanger arrangement are reported here. The two condensers differ only in the manner of circuiting the refrigerant tubes, where one has refrigerant always flowing downward in the active heat transfer region ("identical order") and the other has refrigerant alternating flow direction in the active heat transfer region ("inverted order"). All other geometric parameters, such as bce are% fin louver geometry, refrigerant tube size and enhancement etc., are the same for both heat exchangers. One refrigerant mixture (R-41OA) un&rgoes a small temperature change ("low glide") during phase change, and the other retligerant mixture (a multi- component proprietary mixture) has a substantial temperature change ("high glide") of approximately 10"C during the phase change process. The overall thermal conductance, two-phase conductance, and pressure drop are presented. For the flow conditions of these tests, which are representative of resi&ntial cooling conditions, inverted order circuiting is more desirable than identical order. The potential thermal advantages of the i&ntical order arrangement for high-glide zeotropic refrigerant mixtures are negated by the increased parasitic refrigerant-side pressure drop utiortunately resulting from tkbrication requirements of the identical order circuiting.

  11. Accelerated screening methods for determining chemical and thermal stability of refrigerant-lubricant mixtures: Part 2, Experimental comparison and verification of methods. Quarterly technical progress report, 1 July 1993--30 September 1993

    SciTech Connect

    Kauffman, R.

    1993-12-01

    Research reported continued to concentrate on in situ conductivity measurements for development of an accelerated screening method for determining the chemical and thermal stabilities of refrigerant/lubricant mixtures. Tungsten rods were sealed into the round bottoms of the sealed tubes to provide electrical connections for in situ conductivity measurements. The in situ conductivity measurements were used to monitor the degradation of HFC-134a/ester oil mixtures heated at 175 C (347 F) for two days. Preliminary results indicate that the in situ conductivity measurements correlate with H-1 34a/oil degradation as determined by color measurements. A short study to evaluate the potential of in situ color measurements for development into an accelerated screening test was also performed. Initial results indicate that the in situ color measurements are not well suited for long-term, in situ degradation measurements.

  12. Are National HFC Inventory Reports Accurate?

    NASA Astrophysics Data System (ADS)

    Lunt, M. F.; Rigby, M. L.; Ganesan, A.; Manning, A.; O'Doherty, S.; Prinn, R. G.; Saito, T.; Harth, C. M.; Muhle, J.; Weiss, R. F.; Salameh, P.; Arnold, T.; Yokouchi, Y.; Krummel, P. B.; Steele, P.; Fraser, P. J.; Li, S.; Park, S.; Kim, J.; Reimann, S.; Vollmer, M. K.; Lunder, C. R.; Hermansen, O.; Schmidbauer, N.; Young, D.; Simmonds, P. G.

    2014-12-01

    Hydrofluorocarbons (HFCs) were introduced as replacements for ozone depleting chlorinated gases due to their negligible ozone depletion potential. As a result, these potent greenhouse gases are now rapidly increasing in atmospheric mole fraction. However, at present, less than 50% of HFC emissions, as inferred from models combined with atmospheric measurements (top-down methods), can be accounted for by the annual national reports to the United Nations Framework Convention on Climate Change (UNFCCC). There are at least two possible reasons for the discrepancy. Firstly, significant emissions could be originating from countries not required to report to the UNFCCC ("non-Annex 1" countries). Secondly, emissions reports themselves may be subject to inaccuracies. For example the HFC emission factors used in the 'bottom-up' calculation of emissions tend to be technology-specific (refrigeration, air conditioning etc.), but not tuned to the properties of individual HFCs. To provide a new top-down perspective, we inferred emissions using high frequency HFC measurements from the Advanced Global Atmospheric Gases Experiment (AGAGE) and the National Institute for Environmental Studies (NIES) networks. Global and regional emissions information was inferred from these measurements using a coupled Eulerian and Lagrangian system, based on NCAR's MOZART model and the UK Met Office NAME model. Uncertainties in this measurement and modelling framework were investigated using a hierarchical Bayesian inverse method. Global and regional emissions estimates for five of the major HFCs (HFC-134a, HFC-125, HFC-143a, HFC-32, HFC-152a) from 2004-2012 are presented. It was found that, when aggregated, the top-down estimates from Annex 1 countries agreed remarkably well with the reported emissions, suggesting the non-Annex 1 emissions make up the difference with the top-down global estimate. However, when these HFC species are viewed individually we find that emissions of HFC-134a are over-reported, with all other species being under-reported. Therefore, the approximate agreement between top-down and bottom-up aggregated Annex 1 emissions appears to be the result of a fortuitous cancellation of errors in the individual HFC emissions reports.

  13. TESTING OF REFRIGERANT MIXTURES IN RESIDENTIAL HEAT PUMPS

    EPA Science Inventory

    The report gives results of an investigation of four possibilities for replacing Hydrochlorofluorocarbon-22 (HCFC-22) with the non-ozone-depleting new refrigerants R-407D and R-407C in residential heat pumps. The first and simplest scenario was a retrofit with no hardware modific...

  14. 40 CFR Appendix D to Subpart B of... - SAE J2810 Standard for Recovery Only Equipment for HFC-134a Refrigerant

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... removed from, motor vehicle air-conditioning systems. 1. Scope The purpose of this SAE Standard is to...-conditioning (A/C) system with this equipment be directly returned to a mobile A/C system. This information... (R-134a) A/C systems. 1.1Improved refrigerant recovery equipment is required to ensure...

  15. 40 CFR Appendix D to Subpart B of... - SAE J2810 Standard for Recovery Only Equipment for HFC-134a Refrigerant

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... removed from, motor vehicle air-conditioning systems. 1. Scope The purpose of this SAE Standard is to...-conditioning (A/C) system with this equipment be directly returned to a mobile A/C system. This information... (R-134a) A/C systems. 1.1Improved refrigerant recovery equipment is required to ensure...

  16. 40 CFR Appendix D to Subpart B of... - SAE J2810 Standard for Recovery Only Equipment for HFC-134a Refrigerant

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., DC 20402-9320. CFR 49, Section 173.304Shippers—General Requirements for Shipments and Packagings. 2.1...). This will ensure that the container meets Department of Transportation (DOT) Standard, CFR Title 49... Systems. 2.1.2ARI Publication Available from Air-Conditioning and Refrigeration Institute, 4100...

  17. 40 CFR Appendix D to Subpart B of... - SAE J2810 Standard for Recovery Only Equipment for HFC-134a Refrigerant

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., DC 20402-9320. CFR 49, Section 173.304Shippers—General Requirements for Shipments and Packagings. 2.1...). This will ensure that the container meets Department of Transportation (DOT) Standard, CFR Title 49... Systems. 2.1.2ARI Publication Available from Air-Conditioning and Refrigeration Institute, 4100...

  18. 40 CFR Appendix D to Subpart B of... - SAE J2810 Standard for Recovery Only Equipment for HFC-134a Refrigerant

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., DC 20402-9320. CFR 49, Section 173.304Shippers—General Requirements for Shipments and Packagings. 2.1...). This will ensure that the container meets Department of Transportation (DOT) Standard, CFR Title 49... Systems. 2.1.2ARI Publication Available from Air-Conditioning and Refrigeration Institute, 4100...

  19. 40 CFR Appendix D to Subpart B of... - SAE J2810 Standard for Recovery Only Equipment for HFC-134a Refrigerant

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., DC 20402-9320. CFR 49, Section 173.304Shippers—General Requirements for Shipments and Packagings. 2.1...). This will ensure that the container meets Department of Transportation (DOT) Standard, CFR Title 49... Systems. 2.1.2ARI Publication Available from Air-Conditioning and Refrigeration Institute, 4100...

  20. 40 CFR Appendix D to Subpart B of... - SAE J2810 Standard for Recovery Only Equipment for HFC-134a Refrigerant

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., DC 20402-9320. CFR 49, Section 173.304Shippers—General Requirements for Shipments and Packagings. 2.1...). This will ensure that the container meets Department of Transportation (DOT) Standard, CFR Title 49... Systems. 2.1.2ARI Publication Available from Air-Conditioning and Refrigeration Institute, 4100...

  1. NEW CHEMICAL ALTERNATIVE FOR OZONE-DEPLETING SUBSTANCES: HFC-236FA

    EPA Science Inventory

    The report gives results of a preliminary evaluation of a new hydrofluorocarbon (HFC)--HFC-236fa or 1,1,1,3,3,3-hexafluoropropane--as a possible alternative for chlorofluorocarbon (CFC)-114 (1,2-dichloro-1,1,2,2-tetrafluoroethane) refrigerant for chillers and as a possible fire s...

  2. Evaluation of HFC 245ca and HFC 236ea as foam blowing agents

    NASA Technical Reports Server (NTRS)

    Sharpe, Jon; Macarthur, Doug; Kollie, Tom; Graves, Ron; Liu, Matthew; Hendriks, Robert V.

    1995-01-01

    Hydrochlorofluorocarbon (HCFC) 141b has been selected as the interim blowing agent for use in urethane insulations on NASA's Space Shuttle External Tank. Due to the expected limited commercial lifetime of this material, research efforts at the NASA Thermal Protection Systems Materials Research Laboratory at the Marshall Space Flight Center are now being devoted to the identification and development of alternatives with zero ozone depletion potential. Physical blowing agents identified to date have included hydrocarbons, fluorocarbons, hydrofluoroethers, and more predominantly, hydrofluorocarbons (HFCs). The majority of the HFC evaluations in industry have focused on the more readily available, low boiling candidates such as HFC 134a. Higher boiling HFC candidates that could be handled at ambient conditions and use current processing equipment would be more desirable. This paper will describe results from a research program of two such candidate HFC's performed as a cooperative effort between Martin Marietta Manned Space Systems, the U.S. Environmental Protection Agency, and Oak Ridge National Laboratories. The purpose of this effort was to perform a cursory evaluation of the developmental HFC's 245ca and 236ea as blowing agents in urethane based insulations. These two materials were selected from screening tests of 37 C2, C3, and C4 isomers based on physical properties, atmospheric lifetime, flammability, estimated toxicity, difficulty of synthesis, suitability for dual use as a refrigerant, and other factors. Solubility of the two materials in typical foam components was tested, pour foaming trials were performed, and preliminary data were gathered regarding foam insulation performance.

  3. Chemical and thermal stability of refrigerant-lubricant mixtures with metals

    SciTech Connect

    Huttenlocher, D.F.

    1992-10-09

    This report presents the results of a sealed tube stability study on twenty-one refrigerant-lubricant mixtures selected from the following groupings: HFCs R-32, R-125, R-134, R-134a, R-143a, and R-152a with one or more lubricants selected from among three pentaerythritol esters and three polyalkylene glycols. All lubricants were carefully predried to 25 ppm or less moisture content. HCFCs R-22, R-123, R-124, and R-142b, as well as CFC R-11, with one or more lubricants selected from among two mineral oils and one alkylbenzene fluid. Bach test mixture was aged at three temperature levels.

  4. Chemical and thermal stability of refrigerant-lubricant mixtures with metals. Final report

    SciTech Connect

    Huttenlocher, D.F.

    1992-10-09

    This report presents the results of a sealed tube stability study on twenty-one refrigerant-lubricant mixtures selected from the following groupings: HFCs R-32, R-125, R-134, R-134a, R-143a, and R-152a with one or more lubricants selected from among three pentaerythritol esters and three polyalkylene glycols. All lubricants were carefully predried to 25 ppm or less moisture content. HCFCs R-22, R-123, R-124, and R-142b, as well as CFC R-11, with one or more lubricants selected from among two mineral oils and one alkylbenzene fluid. Bach test mixture was aged at three temperature levels.

  5. Compatibility of refrigerants and lubricants with motor materials

    SciTech Connect

    Doerr, R.; Kujak, S.

    1992-07-23

    During this last quarter, evaluations were complete on the motor materials after 500-hr exposures to refrigerants CFC-123, HFC-134a and HCFC-22 at 90{degrees}C. Materials were also evaluated after exposure to nitrogen at 127{degrees}C to determine effect of the thermal exposure. Other exposures were started during this quarter with refrigerants HCFC-124, HFC-125, HFC-143a, HFC-32 and HFC-152a. One 500 hr exposure is set up per week and one is analyzed the same week. This will enable Trane to complete the 500 hour exposures by the end of the year.

  6. Evaluation of performance and composition shift of zeotropic mixtures in a Lorenz-Meutzner refrigerator/freezer

    SciTech Connect

    Baskin, E.; Smith, N.D.; Delafield, F.R.; Tufts, M.W.

    1999-07-01

    Results from previous testing of this refrigerator/freezer using a 750 Btu/h compressor and several zeotropic mixtures revealed a performance enhancement up to 16% above that of hydrofluorocarbon R-134a. In the study presented in this paper, the Lorenz-Meutzner (LM) refrigerator/freezer equipped with a 1060 Btu/h compressor, two evaporators, and two intercoolers was experimentally tested in an environmental chamber according to the Association of Home Appliance Manufacturers/Department of Energy (AHAM/DOE) testing standards using several hydrofluoropropane-based zeotropic mixtures. The results are compared to baseline testing with R-134a and results obtained using the 750 Btu/h compressor. Hydrofluorocarbons R-245ca/R-152a performed comparably to R-134a. R-245ca/hydrocarbon R-270 (cyclopropane C{sub 3}H{sub 6}) outperformed all zeotropic mixtures and R-134a by at least 12.2 {+-} 0.7%. All refrigerants performed better using the larger compressor due to its inherently better efficiency. Refrigerant samples taken during refrigerator/freezer operation revealed substantial composition shifts (e.g., a 30% running composition shift of R-134a in the R-245ca/R-134a mixture). Sand et al. (1993) obtained an approximately 20% energy reduction using steady-state on-cycle energy consumption results; a comparison was made between chlorofluorocarbon R-12 and a hydrofluorocarbon R-32/hydrochlorofluorocarbon R-124 mixture. Lorenz and Meutzner (1975), originators of the Lorenz-Meutzner refrigerator/freezer design, state that the following parameters influence the optimum performance of the design: (1) heat exchanger size, (2) capillary tube length, (3) refrigerant charge, and (4) compressor size. This work investigates three of these parameters--capillary tube length, compressor size, and refrigerant charge.

  7. Adsorption of Hydrofluorocarbons HFC-134 and HFC-134A on X and Y Zeolites: Effect of Ion-Exchange on Selectivity and Heat of Adsorption

    E-print Network

    Siperstein, Flor R.

    rapidly as worldwide refrigerator and air-conditioner production rises almost exponentially.1 A byproduct zeolite would be highly effective for gas separation. 1. Introduction HFC-134a (CH2FCF3) is a hydrofluorocarbon coolant for refrigerators designated to replace the ozone-damaging chloro- fluorocarbons (CFCs

  8. Pool boiling heat transfer of refrigerant mixtures R32/R125

    SciTech Connect

    Shen, J.; Spindler, K.; Hahne, E.

    1999-11-01

    Nucleate pool boiling heat transfer of new, environmentally harmless refrigerant mixtures R32/R125 has been systematically investigated in a wide range of pressure and heat flux under saturation conditions using a horizontal platinum wire (d = 0.1 mm). The platinum wire served as both heating element and resistance thermometer. The experimental results are compared with calculated values using a modified Jungnickel correlation. The comparison between all calculated data and experimental data shows good agreement. Most of the data fall within {+-}20% of the correlation. The mean average deviation is {+-}8.25%.

  9. Compatibility of refrigerants and lubricants with motor materials

    SciTech Connect

    Doerr, R.; Kujak, S.

    1992-10-01

    During the compatibility study of 10 pure refrigerants with 24 motor materials, it was observed that the greatest damage to the insulation system was caused by absorption of refrigerant followed by rapid desorption. The observed effects were blisters, cracking, internal bubbles and delamination. Measured results includes decreased bond strength, dielectric strength and overall integrity of the material. Refrigerants HCFC-22, HFC-32, HFC-134 and HFC-152a exhibited this phenomena. The effect of HCFC-22 was most severe of the tested refrigerants. Since HCFC-22 has an excellent reliability history with many of the materials tested, compatibility with the new refrigerants is expected.

  10. Accelerated test methods for predicting the life of motor materials exposed to refrigerant/lubricant mixtures. Phase 1, Conceptual design: Final report

    SciTech Connect

    Ellis, P.F. II; Ferguson, A.

    1993-08-18

    The federally mandated phase-out of chlorofluorocarbon refrigerants requires screening tests for motor materials compatibility with alternative refrigerant/lubricant mixtures. In the current phase of the program, ARTI is supporting tests of promising candidate refrigeration/lubricant systems in key refrigeration component systems such as bearings and hermetic motor insulation systems to screen for more subtle detrimental effects and allow estimates of motor-compressor life. This report covers: mechanisms of failure of hermetic motor insulation, current methods for estimation of life of hermetic motors, and conceptual design of improved stator simulator device for testing of alternative refrigerant/lubricant mixtures.

  11. COMPARISON OF CFC-114 AND HFC-236EA PERFORMANCE IN SHIPBOARD VAPOR COMPRESSION SYSTEMS

    EPA Science Inventory

    The report gives results of a comparison of the performance of two refrigerants - 1,1,1,2,3,3-hexafluoropropane (HFC-236ea) and 1,2-dichloro-tetrafluoroethane (CFC-114) - in shipboard vapor compression refrigeration systems. (NOTE: In compliance with the Montreal Protocol and Dep...

  12. Energy Efficient Commercial Refrigeration with Carbon Dioxide Refrigerant and Scroll Expanders

    SciTech Connect

    Dieckmann, John

    2013-04-04

    Current supermarket refrigeration systems are built around conventional fluorocarbon refrigerantsHFC-134a and the HFC blends R-507 and R404A, which replaced the CFC refrigerants, R-12 and R-502, respectively, used prior to the Montreal Protocol phase out of ozone depleting substances. While the HFC refrigerants are non-ozone depleting, they are strong greenhouse gases, so there has been continued interest in replacing them, particularly in applications with above average refrigerant leakage. Large supermarket refrigeration systems have proven to be particularly difficult to maintain in a leak-tight condition. Refrigerant charge losses of 15% of total charge per year are the norm, making the global warming impact of refrigerant emissions comparable to that associated with the energy consumption of these systems.

  13. Solubility, viscosity and density of refrigerant/lubricant mixtures. Final technical report, [1 October 1992--19 April 1994

    SciTech Connect

    Henderson, D.R.

    1994-04-01

    This report presents the results of experimental measurements on low refrigerant concentration mixtures (0, 10, 20 and 30 weight percent) and high refrigerant concentration mixtures (80, 90 and 100 weight percent) of chlorofluorocarbon (CFC) 12, hydrochlorofluorocarbons (HCFC`s) 22, 123, 124 and 142b, and hydrofluorocarbons (BFC`s) 134a, 32, 125, 152a and 143a with mineral oil, alkylbenzene, polyalkylene glycol and polyolester lubricants. Viscosity, solubility (vapor pressure) and density data are reported for thirty five working fluids which are selected combinations of these refrigerants and companion lubricants. These data, reduced to engineering form, are presented in the form of a Daniel Chart and a plot of density versus temperature and composition. Extensive numerical analysis has been performed in order to derive equations which allow two independent variables (temperature and composition) and to provide for corrections in composition due to vapor space volume in the test apparatus.

  14. Vapor-Liquid Equilibrium Measurements of the Binary R32+R125 Refrigerant Mixture

    NASA Astrophysics Data System (ADS)

    Higashi, Yukihiro; Miyake, Takeshi; Fujii, Ken-Ichi

    Vapor-liquid equilibrium (VLE) data of the binary R32+R125 refrigerant mixture including R410A (50mass% R32 + 50mass% R125) were obtained by the circulation-type experimental apparatus with a liquid-bath thermostat. VLE measurements were carried out in the temperatures between 263.15 K and 318.15 K and in the pressures between 505 kPa and 2724 kPa. The experimental uncertainties of temperature, pressure, and composition measurements were estimated to be within 3 mK, 0.1 %, and 0.4 %, respectively. The present data were compared with reported experimental data against the REFPROP 6.01 as well as REFPROP 7.0 calculation results.

  15. An Experimental Investigaton of the Effect of Oil on Convective Heat Trasfer and Pressure Drop of a HFC-32/HRC-125 Mixture 

    E-print Network

    McJimsey, Bert Ashford

    1994-01-01

    at mass fluxes of 277, 434, 520 and 700 kg/sm^2. Heat fluxes were applied at values of 5100, 7100 and 11000 W/m^2. The heat transfer coefficients and pressure drops were measured at refrigerant qualities of 10, 15, 20, 25, 30, 40 and 60 percent...

  16. Refrigerator

    SciTech Connect

    Burke, E.J.

    1987-02-24

    A refrigerator is described comprising: (a) a housing having a vent compartment and an insulated box having a cooler compartment and a freezer compartment; (b) a thermoelectric heat pump means mounted in the housing, the heat pump means including a finned heat sink of high temperature coefficient material mounted in the vent compartment. A hot plate is attached to the heat sink. A thermopile has a hot side connected to the hot plate and a cold side, a block of high temperature coefficient material is connected to the cold side. An L-shaped bracket of high temperature coefficient material having a vertical portion attached to the block and a horizontal portion extends into the freezer compartment. A freezer compartment of high temperature coefficient material has a bottom attached to the L-shaped horizontal portion. The bottom portion has walls forming an ice cube tray receiving recess whereby the continuous structure of high temperature coefficient material exists between the thermopile and ice cube tray receiving recess to produce a sub freezing temperature in the recess; and (c) an ice cube tray having a shape corresponding to that of the ice cube tray receiving recess whereby five sides of the ice cube tray are in freezing engagement with the bottom recess forming walls for freezing ice cubes.

  17. New chemical alternative for ozone-depleting substances: HFC-236ea. Final report, November 1996-March 1997

    SciTech Connect

    Brna, T.G.; Smith, N.D.; Hendriks, R.V.; Gage, C.L.

    1997-10-01

    The report gives results of a preliminary evaluation of a new hydrofluoro-carbon (HFC-236ea or 1,1,1,2,3,3-hexafluoropropane) as a possible alternative for chlorofluorocarbon (CFC)-114 (1,2-dichloro-1, 1,2,2-tetrafluoroethane) refrigerant in chillers and high-temperature industrial heat pumps. Evaluation tests included an examination of the flammability, stability, thermophysical properties, lubricant/refrigerant characteristics, materials compatibility, inhalation toxicity, and refrigeration performance. HFC-236ea was found to be an excellent alternative for CFC-114 refrigerant.

  18. Theoretical analysis for condensation heat transfer of binary refrigerant mixtures with annular flow in horizontal mini-tubes

    NASA Astrophysics Data System (ADS)

    Zhang, Hui-Yong; Li, Jun-Ming; Sun, Ji-Liang; Wang, Bu-Xuan

    2015-06-01

    A theoretical model is developed for condensation heat transfer of binary refrigerant mixtures in mini-tubes with diameter about 1.0 mm. Condensation heat transfer of R410A and R32/R134a mixtures at different mass fluxes and saturated temperatures are analyzed, assuming that the phase flow pattern is annular flow. The results indicate that there exists a maximum interface temperature at the beginning of condensation process for azeotropic and zeotropic mixtures and the corresponding vapor quality to the maximum value increases with mass flux. The effects of mass flux, heat flux, surface tension and tube diameter are analyzed. As expected, the condensation heat transfer coefficients increase with mass flux and vapor quality, and increase faster in high vapor quality region. It is found that the effects of heat flux and surface tension are not so obvious as that of tube diameter. The characteristics of condensation heat transfer of zeotropic mixtures are consistent to those of azeotropic refrigerant mixtures. The condensation heat transfer coefficients increase with the concentration of the less volatile component in binary mixtures.

  19. Alternative Refrigerants for Building Air Conditioning 

    E-print Network

    Bivens, D. B.

    1996-01-01

    , and HFC-245ca. HCFC-22 is also scheduled for phase-out, and three alternatives for HCFC-22 have been identified: HFC-134a, a near-azeotropic mixture of R32/Rl25, and a zeotropic mixture of R32/R125/R134a. Performance test results, future potential energy...

  20. Enhanced naphthenic refrigeration oils for household refrigerator systems

    SciTech Connect

    Reyes-Gavilan, J.L.; Flak, G.T.; Tritcak, T.R.; Barbour, C.B.

    1997-12-31

    Due to industry concerns about the successful employment of hydrofluorocarbon-immiscible hydrocarbon oils in refrigeration systems, enhanced naphthenic refrigeration oils have been developed. These products have been designed to be more dispersible with hydrofluorocarbon (HFC) refrigerants, such as R-134a, in order to facilitate lubricant return to the compressor and to ensure proper energy efficiency of the system. Bench tests and system performance evaluations indicate the feasibility of these oils for use in household refrigeration applications. Results of these evaluations are compared with those obtained with polyol esters and typical naphthenic mineral oils employed in chlorofluorocarbon (CFC) and hydrochlorofluorocarbon (HCFC) refrigeration applications.

  1. Compatibility of refrigerants and lubricants with motor materials. Quarterly technical progress report, April 1, 1992--June 30, 1992

    SciTech Connect

    Doerr, R.; Kujak, S.

    1992-07-23

    During this last quarter, evaluations were complete on the motor materials after 500-hr exposures to refrigerants CFC-123, HFC-134a and HCFC-22 at 90{degrees}C. Materials were also evaluated after exposure to nitrogen at 127{degrees}C to determine effect of the thermal exposure. Other exposures were started during this quarter with refrigerants HCFC-124, HFC-125, HFC-143a, HFC-32 and HFC-152a. One 500 hr exposure is set up per week and one is analyzed the same week. This will enable Trane to complete the 500 hour exposures by the end of the year.

  2. New chemical alternative for ozone-depleting substances: HFC-245ca. Final report, August 1987-June 1996

    SciTech Connect

    Smith, N.D.; Gage, C.L.; Baskin, E.; Hendriks, R.V.

    1996-12-01

    The report gives results of a preliminary evaluation of a new hydrofluoro-carbon (HF)--HFC-245ca or 1,1,2,2,3-pentafluoropropane as a possible alternative for chlorofluorocarbon (CFC)-11 (trichlorofluoromethane) and hydrochloro-fluorocarbon (HCFC)-123 (1,1,1-trifluoro- 2,2-dichloroethane) refrigerant for low-pressure chillers and as a possible alternative for CFC-111 and HCFC-14lb (1-fluoro-1,1-dichloroethane) blowing agents for polyisocyanurate/polyurethane insulation forms. Evaluation tests included an examination of its flammability, stability, thermophysical properties, lubricant miscibility and lubricity, materials compatibility, acute inhalation toxicity, and refrigeration performance.An azeotrope composed of HFC-245ca and HFC-338mccq (1,1,1,2,3,4,4,4-octafluorobutane) was also examined from the standpointof reducing the flammability of HFC-245ca.

  3. RETROFITTING AN AUTOMOTIVE AIR CONDITIONER WITH HFC-134A, ADDITIVE, AND MINERAL OIL

    EPA Science Inventory

    The paper gives results of an evaluation of a lubricant additive developed for use in retrofitting motor vehicle air conditioners. he additive was designed to enable HFC-134a to be used as a retrofit refrigerant with the existing mineral oil in CVC-12 systems. he goal of the proj...

  4. NEW CHEMICAL ALTERNATIVE FOR OZONE-DEPLETING SUBSTANCES: HFC-236EA

    EPA Science Inventory

    The report gives results of a preliminary evaluation of a new hydrofluorocarbon (HFC-236ea or 1, 1, 1, 2, 3, 3-hexafluoropropane) as a possible alternative for chlorofluorocarbon (CFC)-114 (1, 2-dichloro-1, 1, 2, 2-tetrafluoroethane) refrigerant in chillers and high-temperature i...

  5. Two-Phase Flow of HCFC-22 and HFC-134a through Short Tube Orifices 

    E-print Network

    Yongchan, K.

    2008-01-23

    HCFC-22 and HFC-134a were used with short tube orifices having length to diameter ratios ranging from 5 to 20 in a 9.53 mm (3/8 in.) refrigerant line to investigate both two-phase and subcooled liquid flow entering the short tubes. Flow temperature...

  6. HEAT TRANSFER EVALUATION OF HFC-236EA AND CFC-114 IN CONDENSATION AND EVAPORATION

    EPA Science Inventory

    The report gives results of a heat transfer evaluation of the refrigerants hexafluoropropane (HFC-236ea) and 1,1,2,2-dichloro-tetrafluoroethane (CFC-114). (NOTE: With the mandatory phase-out of chlorofluorocarbons (CFCs), as dictated by the Montreal Protocol and Clean Air Act Ame...

  7. Compatibility of refrigerants and lubricants with motor materials. Quarterly technical progress report, 1 July 1992--30 September 1992

    SciTech Connect

    Doerr, R.; Kujak, S.

    1992-10-01

    During the compatibility study of 10 pure refrigerants with 24 motor materials, it was observed that the greatest damage to the insulation system was caused by absorption of refrigerant followed by rapid desorption. The observed effects were blisters, cracking, internal bubbles and delamination. Measured results includes decreased bond strength, dielectric strength and overall integrity of the material. Refrigerants HCFC-22, HFC-32, HFC-134 and HFC-152a exhibited this phenomena. The effect of HCFC-22 was most severe of the tested refrigerants. Since HCFC-22 has an excellent reliability history with many of the materials tested, compatibility with the new refrigerants is expected.

  8. 40 CFR 82.36 - Approved refrigerant handling equipment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...handling equipment. (a)(1) Refrigerant recycling equipment must be certified by the Administrator...J2788—HFC-134a (R-134a) Recovery/Recycling Equipment and Recovery/Recycling/Recharging for Mobile...

  9. 40 CFR 82.36 - Approved refrigerant handling equipment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...handling equipment. (a)(1) Refrigerant recycling equipment must be certified by the Administrator...J2788—HFC-134a (R-134a) Recovery/Recycling Equipment and Recovery/Recycling/Recharging for Mobile...

  10. 40 CFR 82.36 - Approved refrigerant handling equipment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...handling equipment. (a)(1) Refrigerant recycling equipment must be certified by the Administrator...J2788—HFC-134a (R-134a) Recovery/Recycling Equipment and Recovery/Recycling/Recharging for Mobile...

  11. 40 CFR 82.36 - Approved refrigerant handling equipment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...handling equipment. (a)(1) Refrigerant recycling equipment must be certified by the Administrator...J2788—HFC-134a (R-134a) Recovery/Recycling Equipment and Recovery/Recycling/Recharging for Mobile...

  12. 40 CFR 82.36 - Approved refrigerant handling equipment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...handling equipment. (a)(1) Refrigerant recycling equipment must be certified by the Administrator...J2788—HFC-134a (R-134a) Recovery/Recycling Equipment and Recovery/Recycling/Recharging for Mobile...

  13. New chemical alternative for ozone-depleting substances: HFC-236fa. Final report, December 1996-April 1997

    SciTech Connect

    Smith, N.D.; Brna, T.G.; Gage, C.L.; Hendriks, R.V.

    1997-07-01

    The report gives results of a preliminary evaluation of a new hydrofluoro-carbon (HFC)--HFC-236fa or 1,1,1,3,3,3-hexafluoropropane--asa possible alternative for chlorofluorocarbon (CFC)-114 (1,2-dichloro-1, 1,2,2-tetrafluoroethane) refrigerant for chillers and asa possible fire suppressant replacement for halon-1301 (bromotrifluoromethane). Evaluation tests included an examination of flammability, stability, atmospheric lifetime, thermophysical properties, lubricant miscibility and solubility, materials compatibility, inhalation toxicity, refrigerant performance, heat transfer characteristics, and flame suppression.

  14. Properties and Cycle Performance of Refrigerant Blends Operating Near and Above the Refrigerant Critical Point, Task 1: Refrigerant Properties

    SciTech Connect

    Mark O. McLinden; Arno Laesecke; Eric W. Lemmon; Joseph W. Magee; Richard A. Perkins

    2002-08-30

    The main goal of this project was to investigate and compare the performance of an R410A air conditioner to that of an R22 air conditioner, with specific interest in performance at high ambient temperatures at which the condenser of the R410A system may be operating above the refrigerant's critical point. Part 1 of this project consisted of measuring thermodynamic properties R125, R410A and R507A, measuring viscosity and thermal conductivity of R410A and R507A and comparing data to mixture models in NIST REFPROP database. For R125, isochoric (constant volume) heat capacity was measured over a temperature range of 305 to 397 K (32 to 124 C) at pressures up to 20 MPa. For R410A, isochoric heat capacity was measured along 8 isochores with a temperature range of 303 to 397 K (30 to 124 C) at pressures up to 18 MPa. Pressure-density-temperature was also measured along 14 isochores over a temperature range of 200 to 400 K (-73 to 127 C) at pressures up to 35 MPa and thermal conductivity along 6 isotherms over a temperature range of 301 to 404 K (28 to 131 C) with pressures to 38 MPa. For R507A, viscosity was measured along 5 isotherms over a temperature range of 301 to 421 K (28 to 148 C) at pressures up to 83 MPa and thermal conductivity along 6 isotherms over a temperature range of 301 to 404 K (28 to 131 C) with pressures to 38 MPa. Mixture models were developed to calculate the thermodynamic properties of HFC refrigerant mixtures containing R32, R125, R134a and/or R125. The form of the model is the same for all the blends considered, but blend-specific mixing functions are required for the blends R32/125 (R410 blends) and R32/134a (a constituent binary of R407 blends). The systems R125/134a, R125/143a, R134a/143a, and R134a/152a share a common, generalized mixing function. The new equation of state for R125 is believed to be the most accurate and comprehensive formulation of the properties for that fluid. Likewise, the mixture model developed in this work is the latest state-of-the-art for thermodynamic properties of HFC refrigerant blends. These models were incorporated into version 7 of NIST REFPROP database.

  15. The friction and wear behavior in controlled alternative refrigerant atmosphere

    SciTech Connect

    Mizuhara, K.; Akei, M.; Matsuzaki, T. |

    1994-01-01

    Increased wear occurred in the actual refrigeration compressor when hydrofluorocarbon (HFC) refrigerants were substituted for chlorofluorocarbons (CFCs) to comply with the Montreal Protocol. A cause of this increased wear was believed to be the inferior extreme-pressure (EP) or antiwear capability of the alternative refrigerant HFC-134a as the environment gas, compared to that for CFC-12 refrigerant which is currently used. However, under some severe conditions, it was found that the alternative also showed some antiwear or EP effect by forming a fluoride layer on a sliding surface. The reason HFC-134a did not exhibit a lubricating effect, eventhough it had some capability to form a fluoride layer, was that the sliding condition required for HFCs to form a protective layer was more severe than that occurring in actual compressors. The mechanism of the atmospheric effect of refrigerant gases on friction and wear is also discussed.

  16. Reducing the Carbon Footprint of Commercial Refrigeration Systems Using Life Cycle Climate Performance Analysis: From System Design to Refrigerant Options

    SciTech Connect

    Fricke, Brian A; Abdelaziz, Omar; Vineyard, Edward Allan

    2013-01-01

    In this paper, Life Cycle Climate Performance (LCCP) analysis is used to estimate lifetime direct and indirect carbon dioxide equivalent gas emissions of various refrigerant options and commercial refrigeration system designs, including the multiplex DX system with various hydrofluorocarbon (HFC) refrigerants, the HFC/R744 cascade system incorporating a medium-temperature R744 secondary loop, and the transcritical R744 booster system. The results of the LCCP analysis are presented, including the direct and indirect carbon dioxide equivalent emissions for each refrigeration system and refrigerant option. Based on the results of the LCCP analysis, recommendations are given for the selection of low GWP replacement refrigerants for use in existing commercial refrigeration systems, as well as for the selection of commercial refrigeration system designs with low carbon dioxide equivalent emissions, suitable for new installations.

  17. Halocarbon refrigerant detection methods. Final report

    SciTech Connect

    Tapscott, R.E.; Sohn, C.W.

    1996-01-01

    The Montreal Protocol and the U.S. Clean Air Act limit the production of ozone-depleting substances, including many refrigerants. Three options for cost-effectively phasing out these refrigerants from Army installations are: (1) refrigerant containment, (2) retrofit conversion to accommodate alternative refrigerant, and (3) replacement with cooling systems using alternative refrigerant. This report contributes to the first option by identifying and assessing methods to detect chlorofluorocarbon (CFC), hydrochlorofluorocarbon (HCFC) and hydrofluorocarbon (HFC) refrigerants that leak from air-conditioning and refrigeration systems. As background, the report describes the relevant sections of the Montreal Protocol and the Clean Air Act, and gives an overview of refrigerants. This is followed by a description of the technologies used in refrigerant leak detection, and a survey of detector types available and their price ranges. Appendixes provide an extensive list of detector products and their specifications, plus manufacturer addresses and phone numbers.

  18. The large contribution of projected HFC emissions to future climate forcing

    PubMed Central

    Velders, Guus J. M.; Fahey, David W.; Daniel, John S.; McFarland, Mack; Andersen, Stephen O.

    2009-01-01

    The consumption and emissions of hydrofluorocarbons (HFCs) are projected to increase substantially in the coming decades in response to regulation of ozone depleting gases under the Montreal Protocol. The projected increases result primarily from sustained growth in demand for refrigeration, air-conditioning (AC) and insulating foam products in developing countries assuming no new regulation of HFC consumption or emissions. New HFC scenarios are presented based on current hydrochlorofluorocarbon (HCFC) consumption in leading applications, patterns of replacements of HCFCs by HFCs in developed countries, and gross domestic product (GDP) growth. Global HFC emissions significantly exceed previous estimates after 2025 with developing country emissions as much as 800% greater than in developed countries in 2050. Global HFC emissions in 2050 are equivalent to 9–19% (CO2-eq. basis) of projected global CO2 emissions in business-as-usual scenarios and contribute a radiative forcing equivalent to that from 6–13 years of CO2 emissions near 2050. This percentage increases to 28–45% compared with projected CO2 emissions in a 450-ppm CO2 stabilization scenario. In a hypothetical scenario based on a global cap followed by 4% annual reductions in consumption, HFC radiative forcing is shown to peak and begin to decline before 2050. PMID:19549868

  19. Evaluation of HFC-245ca for commercial use in low pressure chillers. Final report, Volume I

    SciTech Connect

    Keuper, E.F.

    1996-03-01

    Federal regulations banned the production of CFC-11 on January 1, 1996. HCFC-123, the only commercial alternative, will be limited to service applications after January 1, 2020 and will be eliminated from production on January 1, 2030. HFC-245ca has been identified as a potential replacement for CFC-11 in retrofit applications and for HCFC-123 in new chillers, but the marginal flammability of HFC-245ca is a major obstacle to its commercial use as a refrigerant in the United States. This report assesses the commercial viability of HFC-245ca based on its experimental performance in a direct drive low pressure centrifugal chiller exclusive of its flammability characteristics. Three different impeller diameters were tested in the chiller, with all impellers having identical discharge blade angles. Experimental work included tests in a 200 ton 3 stage direct drive chiller with 3 impeller sets properly sized for each of three refrigerants, CFC-11, HCFC-123, and HFC-245ca. The commercial viability assessment focused on both retrofit and new product performance and cost.

  20. 40 CFR 82.36 - Approved refrigerant handling equipment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Approved refrigerant handling equipment. (a)(1) Refrigerant recycling equipment must be certified by the...) Recovery/Recycling Equipment and Recovery/Recycling/Recharging for Mobile Air-Conditioning Systems. (5... Recycling Equipment Intended for Use with both CFC-12 and HFC-134a, Recommended Service Procedure for...

  1. 40 CFR 82.36 - Approved refrigerant handling equipment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Approved refrigerant handling equipment. (a)(1) Refrigerant recycling equipment must be certified by the...) Recovery/Recycling Equipment and Recovery/Recycling/Recharging for Mobile Air-Conditioning Systems. (5... Recycling Equipment Intended for Use with both CFC-12 and HFC-134a, Recommended Service Procedure for...

  2. 40 CFR 82.36 - Approved refrigerant handling equipment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Approved refrigerant handling equipment. (a)(1) Refrigerant recycling equipment must be certified by the...) Recovery/Recycling Equipment and Recovery/Recycling/Recharging for Mobile Air-Conditioning Systems. (5... Recycling Equipment Intended for Use with both CFC-12 and HFC-134a, Recommended Service Procedure for...

  3. 40 CFR 82.36 - Approved refrigerant handling equipment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Approved refrigerant handling equipment. (a)(1) Refrigerant recycling equipment must be certified by the...) Recovery/Recycling Equipment and Recovery/Recycling/Recharging for Mobile Air-Conditioning Systems. (5... Recycling Equipment Intended for Use with both CFC-12 and HFC-134a, Recommended Service Procedure for...

  4. 40 CFR 82.36 - Approved refrigerant handling equipment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Approved refrigerant handling equipment. (a)(1) Refrigerant recycling equipment must be certified by the...) Recovery/Recycling Equipment and Recovery/Recycling/Recharging for Mobile Air-Conditioning Systems. (5... Recycling Equipment Intended for Use with both CFC-12 and HFC-134a, Recommended Service Procedure for...

  5. Proceedings of the 1993 Non-Fluorocarbon Insulation, Refrigeration and Air Conditioning Technology Workshop

    NASA Astrophysics Data System (ADS)

    Sessions included: HFC blown polyurethanes, carbon dioxide blown foam and extruded polystyrenes, plastic foam insulations, evacuated panel insulation, refrigeration and air conditioning, absorption and adsorption and stirling cycle refrigeration, innovative cooling technologies, and natural refrigerants. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

  6. Proceedings of the 1993 non-fluorocarbon insulation, refrigeration and air conditioning technology workshop

    SciTech Connect

    Not Available

    1994-09-01

    Sessions included: HFC blown polyurethanes, carbon dioxide blown foam and extruded polystyrenes, plastic foam insulations, evacuated panel insulation, refrigeration and air conditioning, absorption and adsorption and stirling cycle refrigeration, innovative cooling technologies, and natural refrigerants. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

  7. Boiling and condensation heat transfer correlations for refrigerant-oil mixtures flows inside augmented tubes

    SciTech Connect

    Usmani, G.I.; Ravigururajan, T.S.

    1996-12-31

    General correlations to predict boiling and condensation heat-transfer-coefficient are proposed. Data analyzed include 134a condensation and evaporation of refrigerants such as R-22, R-12, R-113, and R-134a. Wide ranges of mass flux, heat flux, pressure, and vapor velocities are covered. Both low-fin tubes and the micro-fin tubes are considered. For boiling correlation more than 975 data points from four experimental studies are correlated and for condensation more than 525 data points from three experimental studies are correlated. The efforts resulted in the development of simple correlations for predicting the heat-transfer-coefficients during condensation and evaporation inside augmented tubes. The results show that the boiling heat-transfer-coefficients decreased with increasing oil concentration and vapor quality, and increased with tube enhancement severity factor. Increasing mass flux, however, diminished the adverse effect of oil on the heat-transfer-coefficient. During condensation, the presence of oil diminished the heat-transfer performance of a micro-fin tube. The heat-transfer-coefficient decreased with increasing oil concentration used, and also with increasing severity factor.

  8. Future atmospheric abundances and climate forcings from scenarios of global and regional hydrofluorocarbon (HFC) emissions

    NASA Astrophysics Data System (ADS)

    Velders, Guus J. M.; Fahey, David W.; Daniel, John S.; Andersen, Stephen O.; McFarland, Mack

    2015-12-01

    Hydrofluorocarbons (HFCs) are manufactured for use as substitutes for ozone-depleting substances that are being phased out globally under Montreal Protocol regulations. While HFCs do not deplete ozone, many are potent greenhouse gases that contribute to climate change. Here, new global scenarios show that baseline emissions of HFCs could reach 4.0-5.3 GtCO2-eq yr-1 in 2050. The new baseline (or business-as-usual) scenarios are formulated for 10 HFC compounds, 11 geographic regions, and 13 use categories. The scenarios rely on detailed data reported by countries to the United Nations; projections of gross domestic product and population; and recent observations of HFC atmospheric abundances. In the baseline scenarios, by 2050 China (31%), India and the rest of Asia (23%), the Middle East and northern Africa (11%), and the USA (10%) are the principal source regions for global HFC emissions; and refrigeration (40-58%) and stationary air conditioning (21-40%) are the major use sectors. The corresponding radiative forcing could reach 0.22-0.25 W m-2 in 2050, which would be 12-24% of the increase from business-as-usual CO2 emissions from 2015 to 2050. National regulations to limit HFC use have already been adopted in the European Union, Japan and USA, and proposals have been submitted to amend the Montreal Protocol to substantially reduce growth in HFC use. Calculated baseline emissions are reduced by 90% in 2050 by implementing the North America Montreal Protocol amendment proposal. Global adoption of technologies required to meet national regulations would be sufficient to reduce 2050 baseline HFC consumption by more than 50% of that achieved with the North America proposal for most developed and developing countries.

  9. ZnO nanorefrigerant in R152a refrigeration system for energy conservation and green environment

    NASA Astrophysics Data System (ADS)

    Sendil Kumar, D.; Elansezhian, R.

    2014-03-01

    In this paper the reliability and performance of a vapour compression refrigeration system with ZnO nanoparticles in the working fluid was investigated experimentally. Nanorefrigerant was synthesized on the basis of the concept of the nanofluids, which was prepared by mixing ZnO nanoparticles with R152a refrigerant. The conventional refrigerant R134a has a global warming potential (GWP) of 1300 whereas R152a has a significant reduced value of GWP of 140 only. An experimental test rig is designed and fabricated indigenously in the laboratory to carry out the investigations. ZnO nanoparticles with refrigerant mixture were used in HFC R152a refrigeration system. The system performance with nanoparticles was then investigated. The concentration of nano ZnO ranges in the order of 0.1% v, 0.3% v and 0.5%v with particle size of 50 nm and 150 g of R152a was charged and tests were conducted. The compressor suction pressure, discharge pressure and evaporator temperature were measured. The results indicated that ZnO nanorefrigerant works normally and safely in the system. The ZnO nanoparticle concentration is an important factor considered for heat transfer enhancement in the refrigeration system. The performance of the system was significantly improved with 21% less energy consumption when 0.5%v ZnO-R152a refrigerant. Both the suction pressure and discharge pressure were lowered by 10.5% when nanorefrigerant was used. The evaporator temperature was reduced by 6% with the use of nanorefrigerant. Hence ZnO nanoparticles could be used in refrigeration system to considerably reduce energy consumption. The usage of R152a with zero ozone depleting potential (ODP) and very less GWP and thus provides a green and clean environment. The complete experimental results and their analysis are reported in the main paper.

  10. 40 CFR Appendix C to Subpart B of... - SAE J2788 Standard for Recovery/Recycle and Recovery/Recycle/Recharging Equipment for HFC-134a...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., DC 20402-9320. OT Standard, CFR Title 49, Section 173.304 Shippers—General Requirements for Shipments..., CFR Title 49, Section 173.304 and the American Society of Mechanical Engineers. 7.3Portable refillable.../Recycle and Recovery/Recycle/Recharging Equipment for HFC-134a Refrigerant C Appendix C to Subpart B...

  11. Study on the compatibility of insulation materials for hermetic motor under alternative refrigerants and new lubricants atmosphere

    NASA Astrophysics Data System (ADS)

    Komatsubara, Takeo; Sunaga, Takeshi; Takahashi, Yasuki

    HFC407C and HFC410A were introduced as the alternative refrigerants for HCFC22 in air conditioner to follow the Motreal protocol. But HFCs were also regulated by the Kyoto protocol and natural refrigerants like hydrocarbon (HC) and CO2 are researched and introduced in the market. Under these circumstances the compatibility of motor insulation materials for hermetic motor under alternative refrigerants and lubricants become important. In this paper we discuss the compatibility of magnet wires and films of hermetic motor for air conditioner under atmosphere of HFC407C and HFC410A with POE and PVE lubricants and also discuss it under atmosphere of R600a with mineral oil and CO2 with PAG lubricant in comparison of conventional atmosphere.

  12. Atmospheric histories and global emissions of the anthropogenic hydrofluorocarbons HFC-365mfc, HFC-245fa, HFC-227ea, and HFC-236fa

    E-print Network

    Rigby, Matthew

    We report on ground-based atmospheric measurements and emission estimates of the four anthropogenic hydrofluorocarbons (HFCs) HFC-365mfc (CH[subscript 3]CF[subscript 2]CH[subscript 2]CF[subscript 3], 1,1,1,3,3-pentafluorobutane), ...

  13. Thermodynamic Properties for A Drop-in Refrigerant R-SP34E

    NASA Astrophysics Data System (ADS)

    Kayukawa, Yohei; Hondo, Takashi; Watanabe, Koichi

    Although a transition into several promising HFC alternative refrigerants and their mixtures from conventional CFC and/or HCFC refrigerants is steadily in progress, there still remains a niche to pursue a drop-in refrigerant in some limited engineering applications where the advantage of retrofitting can be emphasized.R-SP34E is one of such drop-in refrigerants to complement R-12 which is a ternary mixture refrigerant consisted of R-134a with minor fractions of propane and ethanol. In this paper, the fundamental thermodynamic properties such as VLE properties and gas-phase PVT properties of R-SP34E are presented. This paper reports the first sets of measured data including 7 dew-and bubble-point pressures and 73 gas-phase PVT properties in the extensive range of temperatures 300-380 K, pressures 0.1-5.2 MPa, and densities up to around the critical density, obtained by employing the Burnett apparatus. In order to complement and confirm the reliability of the measurements, thermodynamic models including a dew-point pressure correlation and a truncated virial equation of state were originally developed in this study. The models were confirmed to exhibit not only excellent reproducibility of the measurements but also the thermodynamic consistency regarding the temperature dependence of the second and third virial coefficients and derived properties such as specific heats or speed of sound. By presenting the reliable thermodynamic model, a systematic information about the thermodynamic properties of R-SP34E is provided in this paper.

  14. Global warming impacts of ozone-safe refrigerants and refrigeration, heating, and air-conditioning technologies

    SciTech Connect

    Fischer, S.; Sand, J.; Baxter, V.

    1997-12-01

    International agreements mandate the phase-out of many chlorine containing compounds that are used as the working fluid in refrigeration, air-conditioning, and heating equipment. Many of the chemical compounds that have been proposed, and are being used in place of the class of refrigerants eliminated by the Montreal Protocol are now being questioned because of their possible contributions to global warming. Natural refrigerants are put forth as inherently superior to manufactured refrigerants because they have very low or zero global warming potentials (GWPs). Questions are being raised about whether or not these manufactured refrigerants, primarily hydrofluorocarbons (HFCs), should be regulated and perhaps phased out in much the same manner as CFCs and HCFCs. Several of the major applications of refrigerants are examined in this paper and the results of an analysis of their contributions to greenhouse warming are presented. Supermarket refrigeration is shown to be an application where alternative technologies have the potential to reduce emissions of greenhouse gases (GHG) significantly with no clear advantage to either natural or HFC refrigerants. Mixed results are presented for automobile air conditioners with opportunities to reduce GHG emissions dependent on climate and comfort criteria. GHG emissions for hermetic and factory built systems (i.e. household refrigerators/freezers, unitary equipment, chillers) are shown to be dominated by energy use with much greater potential for reduction through efficiency improvements than by selection of refrigerant. The results for refrigerators also illustrate that hydrocarbon and carbon dioxide blown foam insulation have lower overall effects on GHG emissions than HFC blown foams at the cost of increased energy use.

  15. Refrigeration and thermometry of liquid {sup 3}He-{sup 4}He mixtures in the ballistic regime

    SciTech Connect

    Koenig, R.; Betat, A.; Pobell, F.

    1994-11-01

    The ballistic regime of liquid {sup 3}He-{sup 4}He mixtures is characterized by a large mean free path {lambda} of the thermal excitations compared to the characteristic dimension of the experiment. We report on investigations of the transport properties of mixtures as well as superfluid {sup 3}He in the ballistic regime by means of the vibrating wire technique. In order to avoid possible sources of heat leaks into the liquid, the experimental setup was built as far as possible of pure materials only. The contribution of a Ag sinter to the heat leak as well as its influence on the attainable minimum temperature of the mixtures were investigated by performing measurements in two similar setups which differed in the size of the heat exchanger by about one order of magnitude. Moreover, we have used the vibrating wire partly immersed in the superfluid {sup 3}He-B phase of a phase-separated mixture as a very sensitive, continuously monitoring thermometer for liquid mixtures in their ballistic regime. The achieved minimum temperature of a 6.8%-mixture at p = 0.35 bar and of a 9.5%-mixture at p = 9.8 bar was 130 {mu}K. This value can be considered as an upper limit for the temperature of the mixtures as the damping of the vibrating wire thermometer saturates at this temperature due to its intrinsic properties.

  16. Average boiling and condensation heat transfer coefficients of the zeotropic refrigerant mixture R22/R142b in a coaxial tube-in-tube heat exchanger

    SciTech Connect

    Meyer, J.P.; Bukasa, J.M.; Kebonte, S.A.

    2000-02-01

    Average boiling and condensation heat transfer coefficients were determined experimentally for a coaxial tube-in-tube heat exchanger used in hot water heat pumps. During manufacturing, the heat exchanger geometry used for the experiments changed from round tubes to elliptical tubes as no spacers were used to keep the inner tube from touching the outer tube. The refrigerant used was two different mixtures of R22 with R142b in mass ratios of 80%/20% and 60%/40%. The results were compared to theoretical results for straight tubes. It was concluded that the theoretical modes do not predict the heat transfer coefficients very well in coaxial tube-in-tube heat exchangers where the annulus touches the inside of the outer tube.

  17. Modeling and testing of fractionation effects with refrigerant blends in an actual residential heat pump system

    SciTech Connect

    Biancardi, F.R.; Pandy, D.R.; Sienel, T.H.; Michels, H.H.

    1997-12-31

    The heating, ventilating, and air-conditioning (HVAC) industry is actively evaluating and testing hydrofluorocarbon (HFC) refrigerant blends as a means of complying with current and impending national and international environmental regulations restricting the use and disposal of conventional chlorofluorocarbon (CFC) and hydrochlorofluorocarbon (HCFC) refrigerants that contribute to the global ozone-depletion effects. While analyses and system performance tools have shown that HFC refrigerant blends offer certain performance, capacity, and operational advantages, there are significant possible service and operational issues that are raised by the use of blends. Many of these issues occur due to the fractionation of the blends. Therefore, the objective of this program was to conduct analyses and experimental tests aimed at understanding these issues, develop approaches or techniques to predict these effects, and convey to the industry safe and reliable approaches. As a result, analytical models verified by laboratory data have been developed that predict the fractionation effects of HFC refrigerant blends (1) when exposed to selected POE lubricants, (2) during the system charging process from large liquid containers, and (3) during system start-up, operation, and shutdown within various system components (where two-phase refrigerant exists) and during selected system and component leakage scenarios. Model predictions and experimental results are presented for HFC refrigerant blends containing R-32, R-134a, and R-125 and the data are generalized for various operating conditions and scenarios.

  18. Overview of CFC replacement issues for household refrigeration

    SciTech Connect

    Vineyard, E.A. ); Roke, L. ); Hallett, F. )

    1991-01-01

    In 1974, the famous ozone depletion theory of Rowland and Molina claimed that chlorofluorocarbons (CFCs) diffuse into the stratosphere where they are broken down by photolysis to release chlorine atoms that catalytically destroy ozone. Although the understanding of the science is still imperfect, there is little doubt that CFCs play a major role in the Antarctic ozone hole phenomenon and the decline in ozone observed in the rest of the world. Another issue that has become increasingly important is the potential of CFCs to change the earth's temperature and to modify the climate. While the main impact in global warming is made by increased concentrations of carbon dioxide, CFCs and other trace gases also contribute to this effect. In an effort to respond to the global environmental threat, a CFC protocol was adopted during a diplomatic conference in Montreal. This document, known as the Montreal Protocol, was ratified in 1988 and put into effect on January 1, 1989. In accordance with Article 6 of the Montreal Protocol, the countries that signed the agreement shall periodically assess the control measures provided for in the Protocol. As part of that assessment process, household refrigeration was investigated to determine the status of CFC-12 replacements. The conclusion was that much progress has been made towards finding a suitable replacement. Compressors designed for HFC-134a have efficiencies comparable to those for CFC-12 and acceptable reliability tests have been obtained with ester lubricants. In addition, other replacements such as R-152a and refrigerant mixtures exist, but will require more study. Cycle options, such as the Stirling cycle, may be viable, but are further out in the future. The impact of new refrigerants is expected to result in elimination of CFC-12 consumption in developed countries by 1997 and in developing countries by 2005.

  19. Overview of CFC replacement issues for household refrigeration

    SciTech Connect

    Vineyard, E.A.; Roke, L.; Hallett, F.

    1991-12-31

    In 1974, the famous ozone depletion theory of Rowland and Molina claimed that chlorofluorocarbons (CFCs) diffuse into the stratosphere where they are broken down by photolysis to release chlorine atoms that catalytically destroy ozone. Although the understanding of the science is still imperfect, there is little doubt that CFCs play a major role in the Antarctic ozone hole phenomenon and the decline in ozone observed in the rest of the world. Another issue that has become increasingly important is the potential of CFCs to change the earth`s temperature and to modify the climate. While the main impact in global warming is made by increased concentrations of carbon dioxide, CFCs and other trace gases also contribute to this effect. In an effort to respond to the global environmental threat, a CFC protocol was adopted during a diplomatic conference in Montreal. This document, known as the Montreal Protocol, was ratified in 1988 and put into effect on January 1, 1989. In accordance with Article 6 of the Montreal Protocol, the countries that signed the agreement shall periodically assess the control measures provided for in the Protocol. As part of that assessment process, household refrigeration was investigated to determine the status of CFC-12 replacements. The conclusion was that much progress has been made towards finding a suitable replacement. Compressors designed for HFC-134a have efficiencies comparable to those for CFC-12 and acceptable reliability tests have been obtained with ester lubricants. In addition, other replacements such as R-152a and refrigerant mixtures exist, but will require more study. Cycle options, such as the Stirling cycle, may be viable, but are further out in the future. The impact of new refrigerants is expected to result in elimination of CFC-12 consumption in developed countries by 1997 and in developing countries by 2005.

  20. Part I: Experimental investigation of the boiling of binary mixtures of Freon-11 and refrigeration lube oils

    SciTech Connect

    Abu-Eishah, S.I.

    1986-01-01

    Several experimental runs have been carried out to study nucleate boiling of binary mixtures consisting of Freon-11 and lube oils such as SUNISO 3GS and 4GS in oil concentrations ranging from 0 to 24% by volume. The effect of the heating source temperature on the rate of boiling at various pressures has been studied and the boiling curves at different oil concentrations and pressures have been investigated at an excess temperature of up to 80/sup 0/C. The experimental data have been used to find the effect of pressure, oil concentration and excess temperature on the boiling heat transfer coefficient. The P-T relations for both kinds of mixtures have been measured at different oil concentrations. The heat lost to the atmosphere have also been studied as a function of oil concentration for both kinds of mixtures.

  1. Alternative Refrigerant Evaluation for High-Ambient-Temperature Environments: R-22 and R-410A Alternatives for Mini-Split Air Conditioners

    SciTech Connect

    Abdelaziz, Omar; Shrestha, Som S.; Munk, Jeffrey D.; Linkous, Randall Lee; Goetzler, William; Guernsey, Matt; Kassuga, Theo

    2015-10-01

    The Oak Ridge National Laboratory (ORNL) High-Ambient-Temperature Evaluation Program for low– global warming potential (Low-GWP) Refrigerants aims to develop an understanding of the performance of low-GWP alternative refrigerants to hydrochlorofluorocarbon (HCFC) and hydrofluorocarbon (HFC) refrigerants in mini-split air conditioners under high-ambient-temperature conditions. This final report describes the parties involved, the alternative refrigerant selection process, the test procedures, and the final results.

  2. INVESTIGATION OF HFC-236EA AND HFC-236FA AS CFC-114 REPLACEMENTS IN HIGH-TEMPERATURE HEAT PUMPS

    EPA Science Inventory

    The paper discusses a thermodynamic analysis of HFC-236ea and HFC-236f as ozone-safe CFC-114 alternatives in a vapor-compression cycle at high-temperature heat-pump conditions. he cooling capacities and the coefficients of performance (COPs) are evaluated. omprehensive calorimete...

  3. Physical and chemical properties of refrigeration lubricants

    SciTech Connect

    Sunami, Motoshi

    1999-07-01

    The physical and chemical properties of refrigeration lubricants are discussed. Although much attention has been focused on the performance of candidate lubricants for use with hydrofluorocarbons (HFCs) in order to obtain satisfactory lubrication performance in compressors, the properties of the lubricants themselves have not been well discussed. In this paper, the properties of refrigeration lube base stocks and of lube-refrigerant mixtures are described, specifically the viscosity, density, and refrigerant solubility, the change in viscosity and density due to solution with HFCs, and the insulation properties of the base stocks and the refrigerant mixture.

  4. Experimental evaluation of automotive air-conditioning using HFC-134a and HC-134a

    NASA Astrophysics Data System (ADS)

    Nasution, Henry; Zainudin, Muhammad Amir; Aziz, Azhar Abdul; Latiff, Zulkarnain Abdul; Perang, Mohd Rozi Mohd; Rahman, Abd Halim Abdul

    2012-06-01

    An experimental study to evaluate the energy consumption of an automotive air conditioning is presented. In this study, these refrigerants will be tested using the experimental rig which simulated the actual cars as a cabin complete with a cooling system component of the actual car that is as the blower, evaporator, condenser, radiators, electric motor, which acts as a vehicle engine, and then the electric motor will operate the compressor using a belt and pulley system, as well as to the alternator will recharge the battery. The compressor working with the fluids HFC-134a and HC-134a and has been tested varying the speed in the range 1000, 1500, 2000 and 2500 rpm. The measurements taken during the one hour experimental periods at 2-minutes interval times for temperature setpoint of 20°C with internal heat loads 0, 500, 700 and 1000 W. The final results of this study show an overall better energy consumption of the HFC-134a compared with the HC-134a.

  5. Energy and global warming impacts of next generation refrigeration and air conditioning technologies

    SciTech Connect

    Sand, J.R.; Fischer, S.K.; Baxter, V.D.

    1996-10-01

    Significant developments have occurred in hydrofluorocarbon (HFC) and the application of ammonia and hydrocarbons as refrigerant working fluids since the original TEWI (Total Equivalent Warming Impact) report in 1991. System operating and performance data on alternative refrigerants and refrigeration technologies justify and updated evaluation of these new alternative refrigerants and competing technologies in well-characterized applications. Analytical and experimental results are used to show quantitative comparisons between HFCS, HFC blends, hydrocarbons, and ammonia, used as refrigerants. An objective evaluation is presented for commercial and near commercial non-CFC refrigerants/blowing agents and alternative refrigeration technologies. This information is needed for objective and quantitative decisions on policies addressing greenhouse gas emissions from refrigeration and air conditioning equipment. The evaluation assesses the energy use and global warming impacts of refrigeration and air conditioning technologies that could be commercialized during the phase out of HCFCS. Quantitative comparison TEWI for two application areas are presented. Opportunities for significant reductions in TEWI are seen with currently known refrigerants through improved maintenance and servicing practices and improved product designs.

  6. Pool boiling of enhanced heat transfer surfaces in refrigerant-oil mixtures and aqueous calcium sulfate solutions

    SciTech Connect

    Curcio, L.A.; Somerscales, E.F.

    1994-08-01

    Pool boiling data of structured surfaces in R113/3GS oil mixtures show a general decrease in heat transfer with oil concentration, degradation in performance of all surfaces at 10% oil, no change in enhancement of the structured surfaces over plain surface, and restoration of performance of the enhanced surfaces upon cleaning in denatured alcohol. Fouling data of structured surfaces in pool boiling of sat. aq. CaSO{sub 4} solution show that effects of fouling (wall superheat changes, deposit weight) are more pronounced at 80 kW/m{sup 2} than at 10 kW/m{sup 2} heat flux; precipitation fouling show an effect within the first 2 h exposure. High flux surfaces have lower deposition weight than other surfaces; thus the deposition rate may depend strongly on wall superheat. The numerous nucleation sites of the enhanced surfaces provide more turbulent motion near the boiling surface than for the plain surface; thus the removal rate should be greater for an enhanced surface, although no removal of a deposit was ever observed.

  7. Feasibility study of transporting wireless CDMA signals over HFC networks

    NASA Astrophysics Data System (ADS)

    Lin, Yu-Min; Way, Winston I.

    1998-06-01

    Wireless access in hybrid fiber/coax (HFC) networks can integrate two major telecommunication infrastructure, i.e., wireless and HFC networks. This paper studies the technical feasibility of integrating IS-95 code-division-multiple- access (CDMA) wireless networks and HFC networks. Capacity estimation of an HFC optical node-based CDMA cellular systems using a return-path channel model is provided. In addition to multiple access interference in IS-95 CDMA networks, the return-path channel model takes into account ingress noise, impulsive noise, and micro-reflections in a coaxial cable transmission system, and laser diode clipping- induced intermodulation noise in an optical fiber link. Furthermore, in our Monte Carlo simulation, we have assumed slow flat fading for radio propagation, and ideal timing recovery and power control.

  8. CFC prices rise above dropping HFC prices, spread should widen

    SciTech Connect

    Kirschner, E.

    1993-12-15

    Chlorofluorocarbon (CFC) replacement hydrofluorocarbon (HFC)-134a has gained an economic edge over CFC-12 in the U.S. says ICI Americas Chemicals & Plastics president Robin Gadsby. Although conversion costs are keeping many customers from making the switch. Gadsby says demand for HFC-134a should exceed global capacity in the mid-1990s. He adds that ICI can recoup its $430-million investment in HFCs.

  9. Alternative Refrigerant Evaluation for High-Ambient Temperature Environments: R-22 and R-410A Alternatives for Mini-Split Air Conditioners

    SciTech Connect

    Abdelaziz, Omar; Munk, Jeffrey D.; Shrestha, Som S.; Linkous, Randall Lee; Goetzler, William; Guernsey, Matt; Kassuga, Theo

    2015-08-01

    The Oak Ridge National Laboratory (ORNL) High-Ambient Temperature Testing Program for Low-GWP Refrigerants aims to develop an understanding of the performance of low-Global Warming Potential (low-GWP) alternatives to Hydrochlorofluorocarbon (HCFC) and Hydrofluorocarbon (HFC) refrigerants in mini-split air conditioners under high ambient temperature conditions. This interim working paper describes the parties involved, the alternative refrigerants selection process, the test procedures, and the preliminary results.

  10. Heat transfer during condensation of HFC-134a and R-404A inside of a horizontal smooth and micro-fin tube

    SciTech Connect

    Sapali, S.N.; Patil, Pradeep A.

    2010-11-15

    In recent small and medium capacity refrigeration systems, the condenser tubes are provided with micro-fins from inside. The vapour refrigerant at the compressor outlet and the condenser inlet is in superheat state. As it advances in the condenser it is in two phases and at the outlet it is in sub cooled liquid. The heat transfer coefficient (HTC) during condensation of HFC-134a and R-404A in a smooth (8.56 mm ID) and micro-fin tubes (8.96 mm ID) are experimentally investigated. Different from previous studies, the present experiments are performed for various condensing temperatures, with superheating and sub cooling and using hermetically sealed compressor. The test runs are done at average saturated condensing temperatures ranging from 35 C to 60 C. The mass fluxes are between 90 and 800 kg m{sup -2} s{sup -1}. The experimental results indicate that the average HTC increases with mass flux but decreases with increasing condensing temperature for both smooth and micro-fin tubes. The average condensation HTCs of HFC-134a and R-404A for the micro-fin tubes were 1.5-2.5 and 1.3-2 times larger than that in smooth tube respectively. The HTCs for R-404A are less than that of HFC-134a. New correlations based on the data gathered during the experimentation for predicting condensation HTCs are proposed for wide range of operating conditions. (author)

  11. Lean flammability limit as a fundamental refrigerant property. Phase 1, Interim technical report, 1 October 1994--31 March 1995

    SciTech Connect

    Womeldorf, C.; King, M.; Grosshandler, W.

    1995-03-31

    Due to the ozone-depleting effects of commonly used chlorofluorocarbon refrigerants, safe environmentally-friendly replacements must be found. HFC-32 (CH{sub 2}F{sub 2}) and other hydrochlorofluorocarbons are potential candidates; however, in contrast with the CFCs, many of these compounds are flammable. Testing the flammability limits of these hydrochlorofluorocarbons using traditional ASTM E-681 methods has produced a range of limits depending upon the vessel and ignition source used. This project demonstrates the feasibility of defining a fundamental flammability limit of HFC-32, that occurs at the limit of a zero strain rate and is independent of ignition source. Using a counterflow twin-flame burner to define extinction points for different strain rates, an extrapolation to zero strain rate is performed. Using this technique, preliminary results on the lean flammability limit of HFC-32 and the critical flammability ratio of HFC-125 (C{sub 2}HF{sub 5}) in ETC-32 are reported.

  12. Literature survey of heat transfer enhancement techniques in refrigeration applications

    SciTech Connect

    Jensen, M.K.; Shome, B.

    1994-05-01

    A survey has been performed of the technical and patent literature on enhanced heat transfer of refrigerants in pool boiling, forced convection evaporation, and condensation. Extensive bibliographies of the technical literature and patents are given. Many passive and active techniques were examined for pure refrigerants, refrigerant-oil mixtures, and refrigerant mixtures. The citations were categorized according to enhancement technique, heat transfer mode, and tube or shell side focus. The effects of the enhancement techniques relative to smooth and/or pure refrigerants were illustrated through the discussion of selected papers. Patented enhancement techniques also are discussed. Enhanced heat transfer has demonstrated significant improvements in performance in many refrigerant applications. However, refrigerant mixtures and refrigerant-oil mixtures have not been studied extensively; no research has been performed with enhanced refrigerant mixtures with oil. Most studies have been of the parametric type; there has been inadequate examination of the fundamental processes governing enhanced refrigerant heat transfer, but some modeling is being done and correlations developed. It is clear that an enhancement technique must be optimized for the refrigerant and operating condition. Fundamental processes governing the heat transfer must be examined if models for enhancement techniques are to be developed; these models could provide the method to optimize a surface. Refrigerant mixtures, with and without oil present, must be studied with enhancement devices; there is too little known to be able to estimate the effects of mixtures (particularly NARMs) with enhanced heat transfer. Other conclusions and recommendations are offered.

  13. A recuperative superfluid stirling refrigerator

    SciTech Connect

    Brisson, J.G.; Swift, G.W.

    1993-07-01

    A superfluid Stirling refrigerator has been built with a counterflow heat exchanger serving as a recuperative regenerator. It has achieved temperatures of 296 mK with a 4% {sup 3}He-{sup 4}He mixture. Cooling power versus temperature and speed is presented for a 6.6% mixture.

  14. Thermoacoustic refrigeration

    NASA Technical Reports Server (NTRS)

    Garrett, Steven L.; Hofler, Thomas J.

    1991-01-01

    A new refrigerator which uses resonant high amplitude sound in inert gases to pump heat is described and demonstrated. The phasing of the thermoacoustic cycle is provided by thermal conduction. This 'natural' phasing allows the entire refrigerator to operate with only one moving part (the loudspeaker diaphragm). The thermoacoustic refrigerator has no sliding seals, requires no lubrication, uses only low-tolerance machine parts, and contains no expensive components. Because the compressor moving mass is typically small and the oscillation frequency is high, the small amount of vibration is very easily isolated. This low vibration and lack of sliding seals makes thermoacoustic refrigeration an excellent candidate for food refrigeration and commercial/residential air conditioning applications. The design, fabrication, and performance of the first practical, autonomous thermoacoustic refrigerator, which will be flown on the Space Shuttle (STS-42), are described, and designs for terrestrial applications are presented.

  15. Density and viscosity measurements of 1,1,1,2-tetrafluoroethane (HFC-134a) from 199 K to 298 K and up to 100 MPa

    SciTech Connect

    Padua, A.A.H.; Fareleira, J.M.N.A.; Calado, J.C.G.; Wakeham, W.A.

    1996-07-01

    New density results for liquid 1,1,1,2-tetrafluoroethane (HFC-134a) along five isotherms from 199 K to 298 K and at pressures up to 100 MPa are presented. The measurements were performed with a new vibrating-wire instrument operated in the forced mode of oscillation and were carried out on a round-robin sample of refrigerant HFC-134a. The viscosity of the fluid was measured simultaneously with the density, using the same vibrating-wire sensor, at temperatures above 248 K over the entire pressure range. The results are compared with recent literature data. The precision of the present values is {+-}0.03% for the density and {+-}0.6% for the viscosity. The corresponding estimated accuracies are {+-}0.05% and {+-}2.5%, respectively.

  16. 46 CFR 154.1735 - Methyl acetylene-propadiene mixture.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...acetylene-propadiene mixture must have a refrigeration system without vapor compression or have a refrigeration system with the following features...separate cargo piping, vent piping, and refrigeration equipment for methyl...

  17. 46 CFR 154.1735 - Methyl acetylene-propadiene mixture.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...acetylene-propadiene mixture must have a refrigeration system without vapor compression or have a refrigeration system with the following features...separate cargo piping, vent piping, and refrigeration equipment for methyl...

  18. 46 CFR 154.1735 - Methyl acetylene-propadiene mixture.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...acetylene-propadiene mixture must have a refrigeration system without vapor compression or have a refrigeration system with the following features...separate cargo piping, vent piping, and refrigeration equipment for methyl...

  19. 46 CFR 154.1735 - Methyl acetylene-propadiene mixture.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...acetylene-propadiene mixture must have a refrigeration system without vapor compression or have a refrigeration system with the following features...separate cargo piping, vent piping, and refrigeration equipment for methyl...

  20. Alternative Drop-in Refrigerant to R22 for Refrigerating System of Refrigerated Warehouse

    NASA Astrophysics Data System (ADS)

    Bandoh, Yuriko; Furuyama, Kyoko; Saito, Motomu; Sato, Haruki; Morimoto, Masanori; Iwasaki, Minoru; Tonouchi, Takashi; Kotani, Yasuhisa

    We tested to use several compositions of a four-component-mixture R 32/125/134a/600 as a refrigerant for replacing R 22 in refrigeration system of refrigerated warehouses. R 32, R 125, and R 134a are hydrofluorocarbons and R 600 is normal butane. The refrigeration system designed for R 22 can be used without any change or with very minor change. By using appropriate composition of the four-component refrigerant, existing refrigeration system can provide best performance because the adjusted properties of the refrigerant can somewhat compensate for the individual hardware problems. Practical operation test was done by using a refrigeration system of nominal cooling capacity of 30.2 kW with a 22 kW two-stage compressor which equipped for an 858m3 refrigerated warehouse maintaining at -30°C. The pressure condition and the coefficient of performance of R 32/125/134a/600 are similar to R 22 from a theoretical viewpoint. The power consumption of R 32/125/134a/600 was small enough or not to be worse than that of R22, which was confirmed from the actual test results.

  1. Reconciling reported and unreported HFC emissions with atmospheric observations.

    PubMed

    Lunt, Mark F; Rigby, Matthew; Ganesan, Anita L; Manning, Alistair J; Prinn, Ronald G; O'Doherty, Simon; Mühle, Jens; Harth, Christina M; Salameh, Peter K; Arnold, Tim; Weiss, Ray F; Saito, Takuya; Yokouchi, Yoko; Krummel, Paul B; Steele, L Paul; Fraser, Paul J; Li, Shanlan; Park, Sunyoung; Reimann, Stefan; Vollmer, Martin K; Lunder, Chris; Hermansen, Ove; Schmidbauer, Norbert; Maione, Michela; Arduini, Jgor; Young, Dickon; Simmonds, Peter G

    2015-05-12

    We infer global and regional emissions of five of the most abundant hydrofluorocarbons (HFCs) using atmospheric measurements from the Advanced Global Atmospheric Gases Experiment and the National Institute for Environmental Studies, Japan, networks. We find that the total CO2-equivalent emissions of the five HFCs from countries that are required to provide detailed, annual reports to the United Nations Framework Convention on Climate Change (UNFCCC) increased from 198 (175-221) Tg-CO2-eq ? y(-1) in 2007 to 275 (246-304) Tg-CO2-eq ? y(-1) in 2012. These global warming potential-weighted aggregated emissions agree well with those reported to the UNFCCC throughout this period and indicate that the gap between reported emissions and global HFC emissions derived from atmospheric trends is almost entirely due to emissions from nonreporting countries. However, our measurement-based estimates of individual HFC species suggest that emissions, from reporting countries, of the most abundant HFC, HFC-134a, were only 79% (63-95%) of the UNFCCC inventory total, while other HFC emissions were significantly greater than the reported values. These results suggest that there are inaccuracies in the reporting methods for individual HFCs, which appear to cancel when aggregated together. PMID:25918401

  2. Reconciling reported and unreported HFC emissions with atmospheric observations

    PubMed Central

    Lunt, Mark F.; Rigby, Matthew; Ganesan, Anita L.; Manning, Alistair J.; Prinn, Ronald G.; O’Doherty, Simon; Mühle, Jens; Harth, Christina M.; Salameh, Peter K.; Arnold, Tim; Weiss, Ray F.; Saito, Takuya; Yokouchi, Yoko; Krummel, Paul B.; Steele, L. Paul; Fraser, Paul J.; Li, Shanlan; Park, Sunyoung; Reimann, Stefan; Vollmer, Martin K.; Lunder, Chris; Hermansen, Ove; Schmidbauer, Norbert; Maione, Michela; Arduini, Jgor; Young, Dickon; Simmonds, Peter G.

    2015-01-01

    We infer global and regional emissions of five of the most abundant hydrofluorocarbons (HFCs) using atmospheric measurements from the Advanced Global Atmospheric Gases Experiment and the National Institute for Environmental Studies, Japan, networks. We find that the total CO2-equivalent emissions of the five HFCs from countries that are required to provide detailed, annual reports to the United Nations Framework Convention on Climate Change (UNFCCC) increased from 198 (175–221) Tg-CO2-eq?y–1 in 2007 to 275 (246–304) Tg-CO2-eq?y–1 in 2012. These global warming potential-weighted aggregated emissions agree well with those reported to the UNFCCC throughout this period and indicate that the gap between reported emissions and global HFC emissions derived from atmospheric trends is almost entirely due to emissions from nonreporting countries. However, our measurement-based estimates of individual HFC species suggest that emissions, from reporting countries, of the most abundant HFC, HFC-134a, were only 79% (63–95%) of the UNFCCC inventory total, while other HFC emissions were significantly greater than the reported values. These results suggest that there are inaccuracies in the reporting methods for individual HFCs, which appear to cancel when aggregated together. PMID:25918401

  3. Field emission from single-crystalline HfC nanowires

    NASA Astrophysics Data System (ADS)

    Yuan, Jinshi; Zhang, Han; Tang, Jie; Shinya, Norio; Nakajima, Kiyomi; Qin, Lu-Chang

    2012-03-01

    Single HfC nanowire field emitter/electrode structures have been fabricated using nano-assembling and electron beam induced deposition. Field ion microscopy has been applied to study the atomic arrangement of facets formed on a field evaporation-modified HfC nanowire tip. Field evaporation and crystal form studies suggest that the {111} and {110} crystal planes have lower work functions, while the {100}, {210}, and {311} planes have higher work functions. Field emission measurement permits us to obtain that the work function of the {111} crystal plane is about 3.4 eV.

  4. Inventory and mitigation opportunities for HFC-134a emissions from nonprofessional automotive service

    NASA Astrophysics Data System (ADS)

    Zhan, Tao; Potts, Winston; Collins, John F.; Austin, Jeff

    2014-12-01

    Many vehicle owners in the United States recharge their vehicles' air conditioning systems with small containers of hydrofluorocarbon-134a (HFC-134a, CH2FCF3), at a frequency estimated to be once every year on average. Such nonprofessional service produces immediate emissions of this potent greenhouse gas during service and from the residual heel in partially used containers. The nonprofessional operations are also associated with increased delayed refrigerant emissions that occur because owners are less likely to repair leaks than professional technicians. In California, an estimated 1.3 million nonprofessional service operations performed each year generate 0.27 ± 0.07 million metric ton CO2 equivalent (MMTCO2e) of immediate emissions and 0.54 ± 0.08 MMTCO2e of delayed emissions, using a Global Warming Potential of 1300 for HFC-134a. The immediate emissions can be largely mitigated by a regulation that requires self-sealing valves and improved labeling instructions on the containers, a deposit-return-recycling program for the containers, and a consumer education program. If 95% of the used containers were to be returned by consumers for recycling of the container heel, the annual immediate emissions would be reduced by 0.26 ± 0.07 MMTCO2e. In the United States, an estimated 24 million nonprofessional service operations are performed each year, generating 5.1 ± 1.4 MMTCO2e of immediate emissions and 10.4 ± 1.5 MMTCO2e of delayed emissions. Mitigation measures equivalent to the California regulation would reduce nationwide immediate emissions by 4.9 ± 1.4 MMTCO2e, if 95% of the used cans were returned for recycling. These business-as-usual emissions and mitigation potentials are projected to stay approximately constant until around 2022, and remain at significant levels into the 2030s.

  5. The development of a proff of principle superfluid Joule-Thomson refrigerator for cooling below 1 Kelvin

    E-print Network

    Miller, Franklin K., 1970-

    2005-01-01

    A new type of sub-Kelvin refrigerator, the superfluid Joule-Thomson refrigerator, has been developed and its performance has been experimentally verified. This refrigerator uses a liquid superfluid mixture of He and 4He ...

  6. Boiling and Condensation Heat Transfer for New Refrigerants HFE245mc and HFE143m Flowing in Horizontal Tubes

    NASA Astrophysics Data System (ADS)

    Mori, Hideo; Yoshida, Suguru; Ohishi, Katsumi

    Hydrofluoroethers (HFEs) have recently been proposed as substitutes to conventional refrigerants including HFCs, since HFEs have zero ozone depletion potential and also smaller global warming potential. HFE245mc and HFE143m are such substitutes to replace CFC114 especially for heat recovery heat pump systems and HFC134a for refrigerating systems, respectively. In the present study, experiments were made on boiling and condensation heat transfer for HFE245mc and HFE143m flowing inside horizontal smooth tubes. For each new refrigerant, there was found no peculiar difference from conventional refrigerants in the characteristics of boiling and condensation heat transfer, as results of comparisons of measured local boiling and condensation heat transfer coefficients with respective correlations applicable to conventional refrigerants; the authors' correlation for boiling and the Haraguchi et al.'s correlation for condensation Comparing the values calculated from the correlations, the heat transfer coefficient for HFE245mc showed to be higher than or equal to that of CFC114 for boiling and condensation. Similarly, the heat transfer coefficient for HFE143m showed to be almost equal to that of HFC134a for boiling and condensation. From the standpoint of heat transfer, therefore, there was no problem in the use of HFE245mc and HFE143m as the alternative refrigerants to CFC114 and HFC134a, respectively.

  7. Measurement of Concentration of Refrigerant in Refrigeration Oil by Capacitance Sensor

    NASA Astrophysics Data System (ADS)

    Fukuta, Mitsuhiro; Yanagisawa, Yadashi; Ogi, Yasuhiro; Tanaka, Junya

    In general, refrigeration oil of good solubility with refrigerant is used in refrigeration compressors, and development of a concentration sensor of refrigerant dissolved in the oil is needed. In this study, oil and refrigerant concentrations are measured with newly developed capacitance sensor which measure the change of dielectric constant with the concentration. It is found that in most cases of oil-refrigerant combinations the dielectric constant of refrigerant is two to three times as large as that of refrigeration oil and the dielectric constant of mixtures increases linearly with the concentration of refrigerant. When measuring the refrigerant concentration of R410A, t he measurement of the concentration by the dielectric constant is also feasible as long as the composition of each refrigerant component dissolved in the oil does not change from the nominal composition. Prototypes of small sensors, such as a cylindrical type and a needle type, are developed and the performance of the needle sensor with shield is preferable. A correlation for a given oil-refrigerant mixture obtained by a large capacitance sensor is applicable for the small sensors after correcting for stray capacitance. Flow of fluid in the sensors does not affect the capacitance measured by the sensors, while bubbles due to foaming do affect the measurement.

  8. Alternatives to CFC-114 in high-temperature heat pumps: Compressor performance with HFC-236ea and HFC-236fa

    SciTech Connect

    Kazachki, G S; Gage, C L; Hendriks, R V

    1996-01-01

    The paper gives results of comprehensive calorimeter tests on a semihermetic compressor with chlorofluorocarbon (CFC)-114, hydrofluorocarbon (HFC)-236ea, and HFC-236fa over a wide range of temperature test conditions: evaporating temperatures from 0 to 35 C and condensing temperatures from 40 to 110 C. Parameters assessed as criteria for performance evaluation and for reliable performance include: cooling capacity; electric power input, current, and voltage; coefficients of performance; compressor volumetric and isentropic efficiencies; and discharge and oil temperatures. Polyolester oil was used as lubricant in the compressor.

  9. Perfluoropropenyl-containing phosphines from HFC replacements.

    PubMed

    Brisdon, Alan K; Ali Ghaba, Hana; Beutel, Bernd; Egjandi, Amina; Addaraidi, Arij; Pritchard, Robin G

    2015-12-01

    A series of new perfluoropropenyl-containing phosphines of the type R3-nP(E-CF[double bond, length as m-dash]CFCF3)n (R = Ph, iPr, n = 1, 2; R = tBu, n = 2) have been prepared from the reaction of the hydrofluoroolefin Z-CF3CF[double bond, length as m-dash]CFH (HFO-1225ye) with base and the appropriate chlorophosphine, while reaction with Cl2PCH2CH2PCl2 gave (CF3CF[double bond, length as m-dash]CF)2PCH2CH2P(CF[double bond, length as m-dash]CFCF3)2, the first example of a bidentate perfluoroalkenyl-containing phosphine. An alternative route to these phosphines based on the room- or low-temperature deprotonation of CF3CF2CH2F (HFC-236ea) gives mainly the E-isomer, but also a small amount of the Z-isomer, the ratio of which depends on the reaction temperature. All of the phosphines could be readily oxidised with either H2O2 or urea·H2O2, and the phosphine selenides R3-nP(Se)(E-CF[double bond, length as m-dash]CFCF3)n (R = Ph, n = 1,2; R = iPr, n = 1; R = tBu, n = 2) were also prepared. The steric and electronic properties of these ligands were determined based on their platinum(ii), palladium(ii) and molybdenum carbonyl complexes. The crystal structures of (CF3CF[double bond, length as m-dash]CF)2PCH2CH2P(CF[double bond, length as m-dash]CFCF3)2, (CF3CF[double bond, length as m-dash]CF)2P(O)CH2CH2P(O)(CF[double bond, length as m-dash]CFCF3)2, iPr2P(Se)(CF[double bond, length as m-dash]CFCF3)2, trans-[PtCl2{Ph(3-n)P(E-CF[double bond, length as m-dash]CFCF3)n}2] (n = 1 or 2), trans-[PdCl2{R2P(E-CF[double bond, length as m-dash]CFCF3)}2] (R = Ph, iPr) and [Mo(CO)4{(CF3CF[double bond, length as m-dash]CF)2PCH2CH2P(CF[double bond, length as m-dash]CFCF3)2}] are reported. PMID:26212860

  10. HFC-6000 for Nuclear I and C Upgrade

    SciTech Connect

    Taylor, Jonathan; Hsu, Allen; Gerardis, Terry; Stevens, John; McCreary, Tim; Yang, Steve

    2006-07-01

    The scalability of the HFC-6000 product line makes it an effective solution for nuclear power plant I and C upgrade applications. Its 19-in. rack-mounted platform provides a modular structure whose components can be used for many different nuclear power plant safety applications. This single-platform solution reduces the overall complexity of I and C implementation by minimizing operational and maintenance requirements. The HFC-6000 product line is designed to operate with either single or multiple control remote units in each channel. The main controller module in a remote unit is the system controller (HFCSBC06), which executes control logic programs, I/O scan, and C-Link communication. All three functions are handled by dedicated 64/32-bit microprocessors. A redundant configuration of system controllers consists of two HFC-SBC06 modules and one HFC-DPM06 dual-ported memory module. The hardware interface with external peripheral equipment is provided by an HFC-PCC06 peripheral interface module in the same rack. This module communicates with dedicated Control Switch Modules (the operator interface for digital control) and M/A stations (the operator interface for analog control), which are mounted on the plant main control board. Individual input/output modules serve as the hardware interface with the field devices under control and are implemented by different types of I/O modules. Each I/O module has a redundant serial communication interface. This serial interface employs a proprietary poll-response intercommunication link (ICL) protocol for communication with the system controllers. When a remote is configured with redundant controllers, the two ICL interfaces on each I/O module are connected to separate system controllers to create a redundant link. The I/O modules can be installed locally or remotely. If the I/O modules are physically remote from the controller, the ICL can be implemented with fiber optics to provide physical and electrical isolation from non-safety components. An HFC-FPD06 Flat Panel Display Module can be used as a human-machine interface (HMI). This HMI is composed of a qualified flat panel display and an HFC-FPC06 FPD controller. The FPC06 module has hardware interfaces for both the ICL and the fast Ethernet C-Link. It is configured as a subordinate to the HFC-SBC06 system controller and controls graphic displays on the HMI; it can also perform data voting and validation functions for redundant or triple redundant safety channels. The HFC-FPC06 can be used in either single or redundant configurations. The Power Supply Module consists of a redundant, rack-mounted power supply set. The typical configuration provides 24-vdc for all logic functions and 48-vdc for excitation power. Individual power supplies are redundant and hot swappable. Currently, HFC-6000 system is being installed in Kori Units no.1 to no.4 for its AAC D/G control and monitoring system and several other NPP I and C upgrade projects. (authors)

  11. Alternatives to ozone depleting refrigerants in test equipment

    NASA Technical Reports Server (NTRS)

    Hall, Richard L.; Johnson, Madeleine R.

    1995-01-01

    This paper describes the initial results of a refrigerant retrofit project at the Aerospace Guidance and Metrology Center (AGMC) at Newark Air Force Base, Ohio. The objective is to convert selected types of test equipment to properly operate on hydrofluorocarbon (HFC) alternative refrigerants, having no ozone depleting potential, without compromising system reliability or durability. This paper discusses the primary technical issues and summarizes the test results for 17 different types of test equipment: ten environmental chambers, two ultralow temperature freezers, two coolant recirculators, one temperature control unit, one vapor degreaser, and one refrigerant recovery system. The postconversion performance test results have been very encouraging: system capacity and input power remained virtually unchanged. In some cases, the minimum operating temperature increased by a few degrees as a result of the conversion, but never beyond AGMC's functional requirements.

  12. Properties and Cycle Performance of Refrigerant Blends Operating Near and Above the Refrigerant Critical Point, Task 2: Air Conditioner System Study

    SciTech Connect

    Piotr A. Domanski; W. Vance Payne

    2002-10-31

    The main goal of this project was to investigate and compare the performance of an R410A air conditioner to that of an R22 air conditioner, with specific interest in performance at high ambient temperatures at which the condenser of the R410A system may be operating above the refrigerant's critical point. Part 1 of this project consisted of conducting comprehensive measurements of thermophysical for refrigerant R125 and refrigerant blends R410A and R507A and developing new equation of state formulations and mixture models for predicting thermophysical properties of HFC refrigerant blends. Part 2 of this project conducted performance measurements of split-system, 3-ton R22 and R410A residential air conditioners in the 80 to 135 F (27.8 to 57.2 C) outdoor temperature range and development of a system performance model. The performance data was used in preparing a beta version of EVAP-COND, a windows-based simulation package for predicting performance of finned-tube evaporators and condensers. The modeling portion of this project also included the formulation of a model for an air-conditioner equipped with a thermal expansion valve (TXV). Capacity and energy efficiency ratio (EER) were measured and compared. The R22 system's performance was measured over the outdoor ambient temperature range of 80 to 135 F (27.8 to 57.2 C). The same test range was planned for the R410A system. However, the compressor's safety system cut off the compressor at the 135.0 F (57.2 C) test temperature. The highest measurement on this system was at 130.0 F (54.4 C). Subsequently, a custom-manufactured R410A compressor with a disabled safety system and a more powerful motor was installed and performance was measured at outdoor temperatures up to 155.0 F (68.3 C). Both systems had similar capacity and EER performance at 82.0 F (27.8 C). The capacity and EER degradation of both systems were nearly linearly dependent with rising ambient outdoor ambient test temperatures. The performance degradation of R410A at higher temperatures was greater than R22. However, the R22 and R410A systems both operated normally during all tests. Visual observations of the R410A system provided no indication of vibrations or TXV hunting at high ambient outdoor test conditions with the compressor operating in the transcritical regime.

  13. Thermoelectric refrigerator

    NASA Technical Reports Server (NTRS)

    Park, Brian V. (Inventor); Smith, Jr., Malcolm C. (Inventor); McGrath, Ralph D. (Inventor); Gilley, Michael D. (Inventor); Criscuolo, Lance (Inventor); Nelson, John L. (Inventor)

    1996-01-01

    A refrigerator is provided which combines the benefits of superinsulation materials with thermoelectric devices and phase change materials to provide an environmentally benign system that is energy efficient and can maintain relatively uniform temperatures for extended periods of time with relatively low electrical power requirements. The refrigerator includes a thermoelectric assembly having a thermoelectric device with a hot sink and a cold sink. The superinsulation materials include a plurality of vacuum panels. The refrigerator is formed from an enclosed structure having a door. The vacuum panels may be contained within the walls of the enclosed structure and the door. By mounting the thermoelectric assembly on the door, the manufacturer of the enclosed structure is simplified and the overall R rating of the refrigerator increased. Also an electrical motor and propellers may be mounted on the door to assist in the circulation of air to improve the efficiency of the cold sink and the hot sink. A propeller and/or impeller is preferably mounted within the refrigerator to assist in establishing the desired air circulation flow path.

  14. Refrigeration Showcases

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Through the Technology Affiliates Program at the Jet Propulsion Laboratory (JPL), valuable modifications were made to refrigerator displays built by Displaymor Manufacturing Company, Inc. By working with JPL, Displaymor could address stiffer requirements that ensure the freshness of foods. The application of the space technology meant that the small business would be able to continue to market its cases without incurring expenses that could threaten the viability of the business, and the future of several dozen jobs. Research and development improvements in air flow distribution and refrigeration coil technology contributed greatly to certifying Displaymor's showcases given the new federal regulations. These modifications resulted in a refrigerator case that will keep foods cooler, longer. Such changes maintained the openness of the display, critical to customer visibility and accessibility, impulse buying, and cross-merchandising.

  15. Drying R-407C and R-410A refrigerant blends with molecular sieve desiccants

    SciTech Connect

    Cohen, A.P.; Tucker, D.M.

    1998-10-01

    The hydrofluorocarbon (HFC) R-32 (CF{sub 2}H{sub 2}) is a component of refrigerant blends in the 407 and 410 series being tested and commercialized for use as replacements for R-502 and the hydrochlorofluorocarbon (HCFC) R-22. The molecular sieve desiccants used with chlorofluorocarbon (CFC) and HCFC mineral oil systems in the past have achieved high water capacity by excluding the refrigerant and adsorbing only the water. Unfortunately, R-32 is adsorbed on commercial type 3A molecular sieve desiccant products. The result of this adsorption is a loss of water capacity when drying R-32 compared to drying R-22 or R-502 and a reduced level of chemical compatibility of the desiccant with the refrigerant. Some compressor manufacturers are seeking a water concentration as low as 10 mg/kg (ppm[wt]) in the circulating refrigerant of polyolester-lubricated refrigerating equipment using these HFC blends. This paper compares unmodified commercial type 3A molecular sieve desiccants with a recently developed, modified 3A molecular sieve that excludes R-32. The modified 3A has better chemical compatibility with R-32 and high water capacity in liquid R-407C and R-410A. The drying rates of the two desiccants in R-407C and R-410A are similar. Data and test methods are reported on refrigerant adsorption, water capacity, drying rate, and chemical compatibility.

  16. 40 CFR Appendix E to Subpart B of... - The Standard for Automotive Refrigerant Recycling Equipment Intended for Use With Both CFC-12 and...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... cannot exceed 80% of volume at 21.1 °C of its maximum rating as defined by DOT standards, 49 CFR 173.304... Refrigerant Recycling Equipment Intended for Use With Both CFC-12 and HFC-134a E Appendix E to Subpart B of...) PROTECTION OF STRATOSPHERIC OZONE Servicing of Motor Vehicle Air Conditioners Pt. 82, Subpt. B, App....

  17. 40 CFR Appendix E to Subpart B of... - The Standard for Automotive Refrigerant Recycling Equipment Intended for Use With Both CFC-12 and...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... cannot exceed 80% of volume at 21.1 °C of its maximum rating as defined by DOT standards, 49 CFR 173.304... Refrigerant Recycling Equipment Intended for Use With Both CFC-12 and HFC-134a E Appendix E to Subpart B of...) PROTECTION OF STRATOSPHERIC OZONE Servicing of Motor Vehicle Air Conditioners Pt. 82, Subpt. B, App....

  18. 40 CFR Appendix E to Subpart B of... - The Standard for Automotive Refrigerant Recycling Equipment Intended for Use With Both CFC-12 and...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 18 2013-07-01 2013-07-01 false The Standard for Automotive Refrigerant Recycling Equipment Intended for Use With Both CFC-12 and HFC-134a E Appendix E to Subpart B of Part 82 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) PROTECTION OF STRATOSPHERIC OZONE Servicing...

  19. 40 CFR Appendix E to Subpart B of... - The Standard for Automotive Refrigerant Recycling Equipment Intended for Use With Both CFC-12 and...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... cannot exceed 80% of volume at 21.1 °C of its maximum rating as defined by DOT standards, 49 CFR 173.304... Refrigerant Recycling Equipment Intended for Use With Both CFC-12 and HFC-134a E Appendix E to Subpart B of...) PROTECTION OF STRATOSPHERIC OZONE Servicing of Motor Vehicle Air Conditioners Pt. 82, Subpt. B, App....

  20. 40 CFR Appendix E to Subpart B of... - The Standard for Automotive Refrigerant Recycling Equipment Intended for Use With Both CFC-12 and...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... cannot exceed 80% of volume at 21.1 °C of its maximum rating as defined by DOT standards, 49 CFR 173.304... Refrigerant Recycling Equipment Intended for Use With Both CFC-12 and HFC-134a E Appendix E to Subpart B of...) PROTECTION OF STRATOSPHERIC OZONE Servicing of Motor Vehicle Air Conditioners Pt. 82, Subpt. B, App....

  1. Field emission from single-crystalline HfC nanowires

    SciTech Connect

    Yuan, Jinshi; Tang, Jie; Zhang Han; Shinya, Norio; Nakajima, Kiyomi; Qin, Lu-Chang

    2012-03-12

    Single HfC nanowire field emitter/electrode structures have been fabricated using nano-assembling and electron beam induced deposition. Field ion microscopy has been applied to study the atomic arrangement of facets formed on a field evaporation-modified HfC nanowire tip. Field evaporation and crystal form studies suggest that the {l_brace}111{r_brace} and {l_brace}110{r_brace} crystal planes have lower work functions, while the {l_brace}100{r_brace}, {l_brace}210{r_brace}, and {l_brace}311{r_brace} planes have higher work functions. Field emission measurement permits us to obtain that the work function of the {l_brace}111{r_brace} crystal plane is about 3.4 eV.

  2. An Evaluation of the Environmental Impact of Different Commercial Supermarket Refrigeration Systems Using Low Global Warming Potential Refrigerants

    SciTech Connect

    Beshr, Mohamed; Aute, Vikrant; Abdelaziz, Omar; Fricke, Brian A; Radermacher, Reinhard

    2014-01-01

    Commercial refrigeration systems consumed 1.21 Quads of primary energy in 2010 and are known to be a major source for refrigerant charge leakage into the environment. Thus, it is important to study the environmental impact of commercial supermarket refrigeration systems and improve their design to minimize any adverse impacts. The system s Life Cycle Climate Performance (LCCP) was presented as a comprehensive metric with the aim of calculating the equivalent mass of carbon dioxide released into the atmosphere throughout its lifetime, from construction to operation and destruction. In this paper, an open source tool for the evaluation of the LCCP of different air-conditioning and refrigeration systems is presented and used to compare the environmental impact of a typical multiplex direct expansion (DX) supermarket refrigeration systems based on three different refrigerants as follows: two hydrofluorocarbon (HFC) refrigerants (R-404A, and R-407F), and a low global warming potential (GWP) refrigerant (N-40). The comparison is performed in 8 US cities representing different climates. The hourly energy consumption of the refrigeration system, required for the calculation of the indirect emissions, is calculated using a widely used building energy modeling tool (EnergyPlus). A sensitivity analysis is performed to determine the impact of system charge and power plant emission factor on the LCCP results. Finally, we performed an uncertainty analysis to determine the uncertainty in total emissions for both R-404A and N-40 operated systems. We found that using low GWP refrigerants causes a considerable drop in the impact of uncertainty in the inputs related to direct emissions on the uncertainty of the total emissions of the system.

  3. Supercooling Refrigerator

    NASA Technical Reports Server (NTRS)

    1986-01-01

    A Goddard/Philips research project resulted in a refrigeration system which works without seals, lubricants or bearings. The system, originally developed to cool satellite-based scientific instruments, has an extensive range of potential spinoffs. It is called the Stirling Cycle Cryogenic Cooler and eliminates friction by using electronically controlled linear magnetic bearings. Mechanical failure, contamination are eliminated.

  4. Refrigeration Servicing.

    ERIC Educational Resources Information Center

    Hamilton, Donald L.; And Others

    This self-study course is designed to familiarize Marine enlisted personnel with the services required to be performed on refrigeration equipment. The course contains four study units. Each study unit begins with a general objective, which is a statement of what the student should learn from the unit. The study units are divided into numbered work…

  5. 46 CFR 151.50-79 - Methyl acetylene-propadiene mixture.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...acetylene-propadiene mixture must have a refrigeration system that does not compress the cargo vapor or have a refrigeration system with the following features...piping system, including the cargo refrigeration system, for tanks to be...

  6. 46 CFR 151.50-79 - Methyl acetylene-propadiene mixture.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...acetylene-propadiene mixture must have a refrigeration system that does not compress the cargo vapor or have a refrigeration system with the following features...piping system, including the cargo refrigeration system, for tanks to be...

  7. 46 CFR 151.50-79 - Methyl acetylene-propadiene mixture.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...acetylene-propadiene mixture must have a refrigeration system that does not compress the cargo vapor or have a refrigeration system with the following features...piping system, including the cargo refrigeration system, for tanks to be...

  8. 46 CFR 151.50-79 - Methyl acetylene-propadiene mixture.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...acetylene-propadiene mixture must have a refrigeration system that does not compress the cargo vapor or have a refrigeration system with the following features...piping system, including the cargo refrigeration system, for tanks to be...

  9. 46 CFR 151.50-79 - Methyl acetylene-propadiene mixture.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...acetylene-propadiene mixture must have a refrigeration system that does not compress the cargo vapor or have a refrigeration system with the following features...piping system, including the cargo refrigeration system, for tanks to be...

  10. Reduced-temperature processing and consolidation of ultra-refractory Ta4HfC5

    SciTech Connect

    Gaballa, Osama; Cook, B. A.; Russell, A. M.

    2013-04-26

    TaC, HfC, and WC powders were subjected to high-energy milling and hot pressing to produce Ta4HfC5, a composite of Ta(4)HfC5 + 30 vol.% WC, and a composite of Ta4HfC5 + 50 vol.% WC. Sub-micron powders were examined after four different milling intervals prior to hot pressing. XRD was used to verify proper phase formation. SEM, relative density, and hardness measurements were used to examine the resulting phases. Hot pressed compacts of Ta4HfC5 showed densification as high as 98.6% along with Vickers hardness values of 21.4 GPa. Similarly, Ta4HfC5 + 30 vol.% WC exhibited 99% densification with a Vickers hardness of 22.5 GPa. These levels of densification were achieved at 1500 degrees C, which is lower than any previously reported sintering temperature for Ta4HfC5. Microhardness values measured in this study were higher than those previously reported for Ta4HfC5. The WC additions to Ta4HfC5 were found to improve densification and increase microhardness. (C) 2013 Elsevier Ltd. All rights reserved.

  11. LABORATORY INVESTIGATIONS OF INTERACTIONS OF IRRADIATED O-XYLENE/NOX/SO2/AIR MIXTURES WITH AQUEOUS MEDIA CONTAINING SODIUM FLUORIDE, SODIUM TRIFLUOROACETATE, AMMONIUM NITRATE AND HYDROGEN PEROXIDE

    EPA Science Inventory

    Laboratory experiments were conducted to investigate interactions between complex air mixtures and aqueous films containing hydrolysis products of hydrochlorofluorocarbon (HCFC) and hydrofluorocarbon (HFC) oxidation products. he experiments consisted of exposing aqueous films con...

  12. Measurements with a recuperative superfluid Stirling refrigerator

    SciTech Connect

    Watanabe, A.; Swift, G.W.; Brisson, J.G.

    1995-08-01

    A superfluid Stirling refrigerator cooled to 168 mK using a 4.9% {sup 3}He- {sup 4}He mixture and exhausting its waste heat at 383 mK. Cooling power versus temperature and speed is presented for 4.9%, 17%, and 36% mixtures. At the highest concentration, a dissipation mechanism of unknown origin is observed.

  13. Magnetic Refrigeration Development

    NASA Technical Reports Server (NTRS)

    Deardoff, D. D.; Johnson, D. L.

    1984-01-01

    Magnetic refrigeration is being developed to determine whether it may be used as an alternative to the Joule-Thomson circuit of a closed cycle refrigerator for providing 4 K refrigeration. An engineering model 4-15 K magnetic refrigerator has been designed and is being fabricated. This article describes the overall design of the magnetic refrigerator.

  14. Fluorescent refrigeration

    DOEpatents

    Epstein, Richard I. (Santa Fe, NM); Edwards, Bradley C. (Los Alamos, NM); Buchwald, Melvin I. (Santa Fe, NM); Gosnell, Timothy R. (Santa Fe, NM)

    1995-01-01

    Fluorescent refrigeration is based on selective radiative pumping, using substantially monochromatic radiation, of quantum excitations which are then endothermically redistributed to higher energies. Ultimately, the populated energy levels radiatively deexcite emitting, on the average, more radiant energy than was initially absorbed. The material utilized to accomplish the cooling must have dimensions such that the exciting radiation is strongly absorbed, but the fluorescence may exit the material through a significantly smaller optical pathlength. Optical fibers and mirrored glasses and crystals provide this requirement.

  15. Refrigerant pressurization system with a two-phase condensing ejector

    DOEpatents

    Bergander, Mark (Madison, CT)

    2009-07-14

    A refrigerant pressurization system including an ejector having a first conduit for flowing a liquid refrigerant therethrough and a nozzle for accelerating a vapor refrigerant therethrough. The first conduit is positioned such that the liquid refrigerant is discharged from the first conduit into the nozzle. The ejector includes a mixing chamber for condensing the vapor refrigerant. The mixing chamber comprises at least a portion of the nozzle and transitions into a second conduit having a substantially constant cross sectional area. The condensation of the vapor refrigerant in the mixing chamber causes the refrigerant mixture in at least a portion of the mixing chamber to be at a pressure greater than that of the refrigerant entering the nozzle and greater than that entering the first conduit.

  16. EVALUATION OF HFC-245FA AS A POTENTIAL ALTERNATIVE FOR CFC-11 IN LOW PRESSURE CHILLERS

    EPA Science Inventory

    The paper reports results of an evaluation of HFC-245fa as a potential alternative for CFC-11 in low pressure chillers. (NOTE: It was reported previously that HFC245ca (1,1,2,2,3-pentafluoro-propane) has many attributes that make it an attractive candidate alternative for CFC-11 ...

  17. NEW CHEMICAL ALTERNATIVE FOR OZONE-DEPLETING SUBSTANCES: HFC-245CA

    EPA Science Inventory

    The report gives results of a preliminary evaluation of a new hydrofluorocarbon (HFC) -- HFC-245ca or 1,1,2,2,3-pentafluoropropane -- as a possible alternative for chlorofluorocarbon (CFC)-11 (trichlorofluoromethane) and hydrochlorofluorocarbon (HCFC)-123 (1,1,1-trifluoro-2,2-dic...

  18. Refrigerant directly cooled capacitors

    DOEpatents

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

    2007-09-11

    The invention is a direct contact refrigerant cooling system using a refrigerant floating loop having a refrigerant and refrigeration devices. The cooling system has at least one hermetic container disposed in the refrigerant floating loop. The hermetic container has at least one electronic component selected from the group consisting of capacitors, power electronic switches and gating signal module. The refrigerant is in direct contact with the electronic component.

  19. Evaluated rate constants for selected HCFC's and HFC's with OH and O((sup)1D)

    NASA Technical Reports Server (NTRS)

    Hampson, Robert F.; Kurylo, Michael J.; Sander, Stanley P.

    1990-01-01

    The chemistry of HCFC's and HFC's in the troposphere is controlled by reactions with OH in which a hydrogen atom is abstracted from the halocarbon to form water and a halo-alkyl radical. The halo-alkyl radical subsequently reacts with molecular oxygen to form a peroxy radical. The reactions of HCFC's and HFC's with O(exp1D) atoms are unimportant in the troposphere, but may be important in producing active chlorine of OH in the stratosphere. Here, the rate constants for the reactions of OH and O(exp1D) with many HFC's and HCFC's are evaluated. Recommendations are given for the five HCFC's and three HFC's specified by AFEAS as primary alternatives as well as for all other isomers of C1 and C2 HCFC's and HFC's where rate data exist. In addition, recommendations are included for CH3CCl3, CH2Cl2, and CH4.

  20. Fluorescent refrigeration

    DOEpatents

    Epstein, R.I.; Edwards, B.C.; Buchwald, M.I.; Gosnell, T.R.

    1995-09-05

    Fluorescent refrigeration is based on selective radiative pumping, using substantially monochromatic radiation, of quantum excitations which are then endothermically redistributed to higher energies. Ultimately, the populated energy levels radiatively deexcite emitting, on the average, more radiant energy than was initially absorbed. The material utilized to accomplish the cooling must have dimensions such that the exciting radiation is strongly absorbed, but the fluorescence may exit the material through a significantly smaller optical pathlength. Optical fibers and mirrored glasses and crystals provide this requirement. 6 figs.

  1. Aging of Polyurethane Foam Insulation in Simulated Refrigerator Panels--One-Year Results with Third-Generation Blowing Agents

    SciTech Connect

    Gabbard, W.A.; Weaver, F.J.; Wilkes, K.E.

    1999-09-27

    Laboratory data are presented on the effect of constant-temperature aging on the apparent thermal conductivity of polyurethane foam insulation for refrigerators and freezers. The foam specimens were blown with HCFC-141b and with three of its potential replacements--HFC-134a, HFC-245fa, and cyclopentane. Specimens were aged at constant temperatures of 90 F, 40 F, and {minus}10 F. Thermal conductivity measurements were made on two types of specimens: full-thickness simulated refrigerator panels containing foam enclosed between solid plastic sheets, and thin slices of core foam cut from similar panels. Results are presented for the first year of a multi-year study for the full-thickness panels and for about 1-1/2 years of aging for the core-foam specimens.

  2. Refrigerant reclaim apparatus

    SciTech Connect

    Van Steenburgh, L.R.

    1992-02-11

    This patent describes an apparatus for reclaiming refrigerant. It comprises: cleaning means for removing gaseous or liquid refrigerant from a container, vaporizing all of the liquid refrigerant and separating oil from the gaseous refrigerant, a compressor for receiving and compressing the gaseous refrigerant from the containers, a condenser for receiving and condensing the gaseous refrigerant from the compressor, storing means for receiving and storing the liquid refrigerant from the condenser, removal means for removing condensed refrigerant out from the storing means, and evacuations beans for evacuating high pressure gaseous refrigerant from the entire apparatus after all of the condenser refrigerant has been removed the storing means; the evacuation means comprised of the three-way solenoid valve and an operator activated switch functionally associated with the solenoid valve wherein the activation of the switch caused the evacuation of high pressure gaseous refrigerant; and the evacuation means located adjacent to and in fluid communication with the exit of the compressor.

  3. REACH. Refrigeration Units.

    ERIC Educational Resources Information Center

    Snow, Rufus; And Others

    As a part of the REACH (Refrigeration, Electro-Mechanical, Air-Conditioning, Heating) electromechanical cluster, this student manual contains individualized instructional units in the area of refrigeration. The instructional units focus on refrigeration fundamentals, tubing and pipe, refrigerants, troubleshooting, window air conditioning, and…

  4. Multiannual top-down estimate of HFC-23 emissions in East Asia.

    PubMed

    Fang, X; Stohl, A; Yokouchi, Y; Kim, J; Li, S; Saito, T; Park, S; Hu, J

    2015-04-01

    Trifluoromethane (CHF3, HFC-23), with a 100-year global warming potential (GWP) of 12400, is regulated under the Kyoto Protocol. HFC-23 emissions in East Asia, especially in China, are currently thought to represent the majority of global HFC-23 emissions. This study provides both a bottom-up emission inventory and the multiannual top-down estimate of HFC-23 emissions in East Asia during 2007-2012. The new bottom-up inventory yields improved simulated HFC-23 mixing ratios compared to previous bottom-up inventories. The top-down estimate uses inverse modeling to further improve the model-measurement agreement. Results show that China contributed 94-98% of all HFC-23 emissions in East Asia. Annual a posteriori emissions from China were around 6.3 Gg/yr during the period 2007-2010 after which they increased to 7.1 ± 0.7 Gg/yr in 2011 and 8.8 ± 0.8 Gg/yr in 2012. For the first time, this study also provides a top-down estimate of HFC-23/HCFC-22 (chlorodifluoromethane, CHClF2) coproduction ratios in non-CDM (Clean Development Mechanism) HCFC-22 production plants as well as in all HCFC-22 production plants in China. PMID:25785483

  5. Stirling Refrigerator

    NASA Astrophysics Data System (ADS)

    Kagawa, Noboru

    A Stirling cooler (refrigerator) was proposed in 1862 and the first Stirling cooler was put on market in 1955. Since then, many Stirling coolers have been developed and marketed as cryocoolers. Recently, Stirling cycle machines for heating and cooling at near-ambient temperatures between 173 and 400K, are recognized as promising candidates for alternative system which are more compatible with people and the Earth. The ideal cycles of Stirling cycle machine offer the highest thermal efficiencies and the working fluids do not cause serious environmental problems of ozone depletion and global warming. In this review, the basic thermodynamics of Stirling cycle are briefly described to quantify the attractive cycle performance. The fundamentals to realize actual Stirling coolers and heat pumps are introduced in detail. The current status of the Stirling cycle machine technologies is reviewed. Some machines have almost achieved the target performance. Also, duplex-Stirling-cycle and Vuilleumier-cycle machines and their performance are introduced.

  6. ARTI refrigerant database

    SciTech Connect

    Calm, J.M.

    1996-07-01

    The Refrigerant Database is an information system on alternative refrigerants, associated lubricants, and their use in air conditioning and refrigeration. It consolidates and facilitates access to property, compatibility, environmental, safety, application and other information. It provides corresponding information on older refrigerants, to assist manufacturers and those using alternative refrigerants, to make comparisons and determine differences. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern.

  7. ARTI refrigerant database

    SciTech Connect

    Calm, J.M.

    1999-01-01

    The Refrigerant Database is an information system on alternative refrigerants, associated lubricants, and their use in air conditioning and refrigeration. It consolidates and facilities access to property, compatibility, environmental, safety, application and other information. It provides corresponding information on older refrigerants, to assist manufacturers and those using alternative refrigerants, to make comparisons and determine differences. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern.

  8. ARTI refrigerant database

    SciTech Connect

    Calm, J.M.

    1996-11-15

    The Refrigerant Database is an information system on alternative refrigerants, associated lubricants, and their use in air conditioning and refrigeration. It consolidates and facilitates access to property, compatibility, environmental, safety, application and other information. It provides corresponding information on older refrigerants, to assist manufacturers and those using alternative refrigerants, to make comparisons and determine differences. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern.

  9. ARTI refrigerant database

    SciTech Connect

    Calm, J.M.

    1996-01-15

    The Refrigerant Database is an information system on alternative refrigerants, associated lubricants, and their use in air conditioning and refrigeration. it consolidates and facilitates.access to property, compatibility, environmental, safety, application and other information. It provides corresponding information on older refrigerants, to assist manufacturers and those using alternative refrigerants, to make comparisons and determine differences. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern.

  10. Historical emissions of HFC-23 (CHF3) in China and projections upon policy options by 2050.

    PubMed

    Fang, Xuekun; Miller, Benjamin R; Su, Shenshen; Wu, Jing; Zhang, Jianbo; Hu, Jianxin

    2014-04-01

    Trifluoromethane (CHF3, HFC-23) is one of the hydrofluorocarbons (HFCs) regulated under the Kyoto Protocol with a global warming potential (GWP) of 14?800 (100-year). China's past, present, and future HFC-23 emissions are of considerable interest to researchers and policymakers involved in climate change. In this study, we compiled a comprehensive historical inventory (1980-2012) and a projection (2013-2050) of HFC-23 production, abatements, and emissions in China. Results show that HFC-23 production in China increased from 0.08 ± 0.05 Gg/yr in 1980 to 15.4 ± 2.1 Gg/yr (228 ± 31 Tg/yr CO2-eq) in 2012, while actual HFC-23 emissions reached a peak of 10.5 ± 1.8 Gg/yr (155 ± 27 Tg/y CO2-eq) in 2006, and decreased to a minimum of 7.3 ± 1.3 Gg/yr (108 ± 19 Tg/yr CO2-eq) in 2008 and 2009. Under the examined business-as-usual (BAU) scenario, the cumulative emissions of HFC-23 in China over the period 2013-2050 are projected to be 609 Gg (9015 Tg CO2-eq which approximates China's 2012 CO2 emissions). Currently, China's annual HFC-23 emissions are much higher than those from the developed countries, while it is estimated that by year 2027, China's historic contribution to the global atmospheric burden of HFC-23 will have surpassed that of the developed nations under the BAU scenario. PMID:24605818

  11. New class of microminiature Joule — Thomson refrigerator and vacuum package

    NASA Astrophysics Data System (ADS)

    Paugh, Robert L.

    1990-12-01

    Progress is reported on the development of a two-stage, fast cooldown Joule — Thomson refrigerator using nitrogen gas and a nitrogen — hydrocarbon gas mixture as the refrigerants. The refrigerator incorporates a microminiature Venturi pump to reduce the pressure of the exhaust of the main boiler to bring the operating temperature of the cold stage to < 70 K in as little as 10 s. The vacuum package for the refrigerator contains no organic materials and is designed to provide a ten year shelf life. Special glass strengthening techniques are being used to achieve cooler survival of acceleration tests of up to 100 000g.

  12. ALTERNATIVES FOR OZONE-DEPLETING REFRIGERANTS

    EPA Science Inventory

    The paper gives results of tests of 2 of 11 compounds and several mixtures selected for intensive evaluation from about 40 new synthesized compounds that may serve as environmentally safe and effective refrigerant alternatives over the long term. he two compounds are: 1, 1, 1, 2,...

  13. Thermodynamic design principle of mixed-gases Kleemenko refrigeration cycles

    NASA Astrophysics Data System (ADS)

    Gong, M. Q.; Luo, E. C.; Wu, J. F.; Zhou, Y.

    2002-05-01

    Mixed-gases throttling refrigeration cycles are recuperative cycles. The refrigeration system has at least one heat exchanger and from zero to three or more phase separators. Detailed discussions are made in this paper on the thermodynamic performance of several cycles, including extensive simulations and optimizations of mixtures, operating parameters of pressures, and flow configurations. The results show that the mixed refrigerant is the most important design parameter that influences the performance of the system. From a thermodynamic point of view, the configurations that were studied can all achieve about the same efficiency with an appropriate selection of the mixture and operating pressures.

  14. Refrigeration for Cryogenic Sensors

    NASA Technical Reports Server (NTRS)

    Gasser, M. G. (editor)

    1983-01-01

    Research in cryogenically cooled refrigerators is discussed. Low-power Stirling cryocoolers; spacecraft-borne long-life units; heat exchangers; performance tests; split-stirling, linear-resonant, cryogenic refrigerators; and computer models are among the topics discussed.

  15. Plant Site Refrigeration Upgrade 

    E-print Network

    Zdrojewski, R.; Healy, M.; Ramsey, J.

    1999-01-01

    Bayer Corporation operates a multi-division manufacturing facility in Bushy Park, South Carolina. Low temperature refrigeration (-4°F) is required by many of the chemical manufacturing areas and is provided by a Plant Site Refrigeration System...

  16. ARTI Refrigerant Database

    SciTech Connect

    Calm, J.M.

    1994-05-27

    The Refrigerant Database consolidates and facilitates access to information to assist industry in developing equipment using alternative refrigerants. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern.

  17. New Rules for Refrigerants.

    ERIC Educational Resources Information Center

    Jackson, Robert

    1999-01-01

    Discusses how educational facilities can comply with new Environmental Protection Agency regulations regarding commercial refrigerants. Tips include developing a compliance plan with a manager in charge of it, and developing an accurate and complete refrigerant-systems assessment. (GR)

  18. ARTI Refrigerant Database

    SciTech Connect

    Calm, J.M.

    1995-06-01

    The Refrigerant Database consolidates and facilitates access to information to assist industry in developing equipment using alternative refrigerants. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern.

  19. ARTI Refrigerant Database

    SciTech Connect

    Calm, J.M.

    1995-02-01

    The Refrigerant Database consolidates and facilitates access to information to assist industry in developing equipment using alternative refrigerants. The underlying purpose is to accelerate phase-out of chemical compounds of environmental concern.

  20. Save with Hybrid Refrigeration 

    E-print Network

    Chung, C. W.

    1985-01-01

    REFRIGERATION Cheng-Wen (Wayne) Chung, P.E. Fluor Engineers, Inc. Irvine, California ABSTRACT Two level demand makes it possible to use two systems for refrigeration and save energy and money. An example of this type of refrigeration, consisting... of an ammonia absorption refrigeration (AAR) unit and a mechanical compression refrigera tion (MCR) unit, is presented in this article. This paper will briefly describe process configur ation, advantages and utility consumption, equip ment cost and direct...

  1. Measurement of viscosity, density, and gas solubility of refrigerant blends in selected synthetic lubricants. Quarterly report, October 1--December 30, 1993

    SciTech Connect

    Cavestri, R.C.

    1994-01-01

    Liquid/liquid miscibilities of four different 32 ISO VG polyolesters and one alkylbenzene at three concentrations have been determined with five refrigerant blends, including HC-290. A vapor lubricant equilibrium (VLE) viscosity reduction of 32 ISO VG mineral oil with HCFC-22 has been completed. Composite viscosity reduction information by the fractionate components from R-502 in 32 ISO VG mineral oil has been obtained from {minus}10{degree}C (14{degree}F) to 125{degree}C (257{degree}F) isotherms. Vapor lubricant equilibrium (VLE) viscosity reduction for 32 ISO VG mixed acid polyolester with HFC-134a and HFC-143a has also been completed. Data is also presented for the viscosity reduction of 32 ISO VG branched acid polyolester by these same refrigerants.

  2. Reciprocating magnetic refrigerator

    NASA Astrophysics Data System (ADS)

    Johnson, D. L.

    1985-05-01

    A 4 to 15 K magnetic refrigerator to test as an alternative to the Joule-Thomson circuit as the low temperature stage of a 4 to 300 K closed-cycle refrigerator was developed. The reciprocating magnetic refrigerator consists of two matrices of gadolinium gallium garnet spheres located in tandem on a single piston which alternately moves each matrix into a 7 telsa magnetic field. A separate helium gas circuit is used as the heat exchange mechanism for the low and the high temperature extremes of the magnetic refrigerator. Details of the design and results of the initial refrigerator component tests are presented.

  3. HFC-23 (CHF3) emission trend response to HCFC-22 (CHClF2) production and recent HFC-23 emission abatement measures

    E-print Network

    Miller, B. R.

    HFC-23 (also known as CHF3 [CHF subscript 3], fluoroform or trifluoromethane) is a potent greenhouse gas (GHG), with a global warming potential (GWP) of 14 800 for a 100-year time horizon. It is an unavoidable by-product ...

  4. Recent increases in trifluoromethane (HFC-23) global emissions and early atmospheric changes observed for other hydrofluorocarbons

    NASA Astrophysics Data System (ADS)

    Montzka, S. A.; Miller, B. R.; Battle, M. O.; Aydin, K. M.; Fahey, D. W.; Hall, B. D.; Miller, L.; Verhulst, K. R.; Saltzman, E.; McFarland, M.

    2009-12-01

    Trifluoromethane (HFC-23) is an unintended by-product of chlorodifluoromethane (HCFC-22) production and has a 100-yr global warming potential of 14,800. Firn-air and ambient air measurements of HFC-23 from three firn sampling excursions to Antarctica between 2001 and 2009 are used to construct a consistent atmospheric history for this chemical in the Southern Hemisphere. The results show continued increases in the atmospheric abundance of HFC-23 and imply substantial increases in HFC-23 global emissions since 2003. These emission increases are coincident with rapidly increasing HCFC-22 production in developing countries and are observed despite efforts in recent years to limit emissions of HFC-23 through the Kyoto Protocol’s Clean Development Mechanism. These results will be considered along with new observations of additional HFCs from archived air, firn air, and ongoing flask-air measurements. Considered together, atmospheric increases observed for hydrochlorofluorocarbons and hydrofluorocarbons accounted for ~9% of the increase in total direct radiative forcing from anthropogenic gases during 2003-2008, an addition that was slightly larger than attributable to N2O over this same period.

  5. Dryout Quality for Refrigerants Flowing in Horizontal Evaporator Tubes

    NASA Astrophysics Data System (ADS)

    Mori, Hideo; Kakimoto, Yasushi; Ohishi, Katsumi

    The present paper reports an investigation of the dryout quality for refrigerants flowing in horizontal evaporator tubes. Experiments were made for the flow of boiling HFC-134a and HCFC-22 inside smooth tubes and a spirally grooved (micro-fin) tube. At given conditions, dryout proceeded over a certain quality range. Therefore two dryout qualities were defined; dryout inception quality at which the circumferentially averaged (axially local) heat transfer coefficient began to decrease rapidly, and dryout completion quality at which the decrease in the heat transfer coefficient ended. Based on the experimental data, the characteristics of both dryout qualities were clarified, and thereby the dryout qualities were classified into three characteristic regimes for the smooth tube and two regimes for the micro-fin tube. A dimensionless correlation of each dryout quality, which can reproduce the measurement successfully, was developed for the respective tubes.

  6. Development of Low Global Warming Potential Refrigerant Solutions for Commercial Refrigeration Systems using a Life Cycle Climate Performance Design Tool

    SciTech Connect

    Abdelaziz, Omar; Fricke, Brian A; Vineyard, Edward Allan

    2012-01-01

    Commercial refrigeration systems are known to be prone to high leak rates and to consume large amounts of electricity. As such, direct emissions related to refrigerant leakage and indirect emissions resulting from primary energy consumption contribute greatly to their Life Cycle Climate Performance (LCCP). In this paper, an LCCP design tool is used to evaluate the performance of a typical commercial refrigeration system with alternative refrigerants and minor system modifications to provide lower Global Warming Potential (GWP) refrigerant solutions with improved LCCP compared to baseline systems. The LCCP design tool accounts for system performance, ambient temperature, and system load; system performance is evaluated using a validated vapor compression system simulation tool while ambient temperature and system load are devised from a widely used building energy modeling tool (EnergyPlus). The LCCP design tool also accounts for the change in hourly electricity emission rate to yield an accurate prediction of indirect emissions. The analysis shows that conventional commercial refrigeration system life cycle emissions are largely due to direct emissions associated with refrigerant leaks and that system efficiency plays a smaller role in the LCCP. However, as a transition occurs to low GWP refrigerants, the indirect emissions become more relevant. Low GWP refrigerants may not be suitable for drop-in replacements in conventional commercial refrigeration systems; however some mixtures may be introduced as transitional drop-in replacements. These transitional refrigerants have a significantly lower GWP than baseline refrigerants and as such, improved LCCP. The paper concludes with a brief discussion on the tradeoffs between refrigerant GWP, efficiency and capacity.

  7. Valerianella radiata (Native) 4 

    E-print Network

    Amanda B. Cemper

    2011-08-02

    . The refrigerants were examined at temperatures near 4°C. Oil was added to the HFC-32/HFC-125 mixture in concentrations of 2.6% and 5.4%. Experiments were repeated with the oil laden refrigerant. The heat transfer coefficients for HCFC-22 increased with quality...

  8. Refrigeration systems program summary

    SciTech Connect

    Not Available

    1991-12-01

    In addition to saving energy, deploying advanced refrigeration technologies can substantially benefit the environment. Chlorofluorocarbons (CFCs) have been identified as a major cause of potential global climate change and about 20% of the CFCs consumed by the United States are due to refrigeration systems. As the international Montreal Protocol will phase out CFC compounds no later than 2000, there is tremendous need to develop safe non-CFC refrigerants and working fluids, alternative refrigeration cycles, an non-CFC insulations for appliances. The US Department of Energy (DOE) established the Refrigeration System Program in 1977 to lead a national effort to accelerate the deployment of cost-effective and energy-efficient air-conditioning and refrigeration technologies. The program primarily conducts research and development on advanced refrigeration technologies. The program-managed by the Office of Building Technologies, which reports to DOE's Assistant Secretary for Conversation and Renewable Energy-encompasses several key activities such as investigating alternative refrigerants and refrigeration cycles, developing advanced technologies for future air-conditioning and refrigeration equipment designs, and developing advanced appliance insulations.

  9. Refrigeration systems program summary

    SciTech Connect

    Not Available

    1991-12-01

    In addition to saving energy, deploying advanced refrigeration technologies can substantially benefit the environment. Chlorofluorocarbons (CFCs) have been identified as a major cause of potential global climate change and about 20% of the CFCs consumed by the United States are due to refrigeration systems. As the international Montreal Protocol will phase out CFC compounds no later than 2000, there is tremendous need to develop safe non-CFC refrigerants and working fluids, alternative refrigeration cycles, an non-CFC insulations for appliances. The US Department of Energy (DOE) established the Refrigeration System Program in 1977 to lead a national effort to accelerate the deployment of cost-effective and energy-efficient air-conditioning and refrigeration technologies. The program primarily conducts research and development on advanced refrigeration technologies. The program-managed by the Office of Building Technologies, which reports to DOE`s Assistant Secretary for Conversation and Renewable Energy-encompasses several key activities such as investigating alternative refrigerants and refrigeration cycles, developing advanced technologies for future air-conditioning and refrigeration equipment designs, and developing advanced appliance insulations.

  10. ARTI refrigerant database

    SciTech Connect

    Calm, J.M.

    1996-04-15

    The Refrigerant Database is an information system on alternative refrigerants, associated lubricants, and their use in air conditioning and refrigeration. It consolidates and facilitates access to property, compatibility, environmental, safety, application and other information. It provides corresponding information on older refrigerants, to assist manufacturers and those using alternative refrigerants, to make comparisons and determine differences. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern. The database provides bibliographic citations and abstracts for publications that may be useful in research and design of air-conditioning and refrigeration equipment. The complete documents are not included, though some may be added at a later date. The database identifies sources of specific information on refrigerants. It addresses lubricants including alkylbenzene, polyalkylene glycol, polyolester, and other synthetics as well as mineral oils. It also references documents addressing compatibility of refrigerants and lubricants with metals, plastics, elastomers, motor insulation, and other materials used in refrigerant circuits. Incomplete citations or abstracts are provided for some documents. They are included to accelerate availability of the information and will be completed or replaced in future updates. Citations in this report are divided into the following topics: thermophysical properties; materials compatibility; lubricants and tribology; application data; safety; test and analysis methods; impacts; regulatory actions; substitute refrigerants; identification; absorption and adsorption; research programs; and miscellaneous documents. Information is also presented on ordering instructions for the computerized version.

  11. Refrigerator Based on Chemisorption

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.

    1987-01-01

    Reversible chemical reaction generates pressurized oxygen for cooling. Concept for cryogenic refrigerator based on chemical absorption of oxygen by praseodymium/cerium oxide (PCO) compound. Refrigerator produces cryogenic liquid for cooling infrared sensors. Also used for liquefying air and separating oxygen from nitrogen in air. In chemisorption refrigerator, PCO alternately absorbs and desorbs oxygen depending on whether cooled or heated. One pair of compressors accepts oxygen while others releases it. Compressed oxygen liquefied when precooked and expanded.

  12. ARTI refrigerant database

    SciTech Connect

    Calm, J.M.

    1997-02-01

    The Refrigerant Database is an information system on alternative refrigerants, associated lubricants, and their use in air conditioning and refrigeration. It consolidates and facilitates access to property, compatibility, environmental, safety, application and other information. It provides corresponding information on older refrigerants, to assist manufacturers and those using alterative refrigerants, to make comparisons and determine differences. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern. The database provides bibliographic citations and abstracts for publications that may be useful in research and design of air-conditioning and refrigeration equipment. The complete documents are not included, though some may be added at a later date. The database identifies sources of specific information on various refrigerants. It addresses lubricants including alkylbenzene, polyalkylene glycol, polyolester, and other synthetics as well as mineral oils. It also references documents addressing compatibility of refrigerants and lubricants with metals, plastics, elastomers, motor insulation, and other materials used in refrigerant circuits. Incomplete citations or abstracts are provided for some documents. They are included to accelerate availability of the information and will be completed or replaced in future updates.

  13. ARTI refrigerant database

    SciTech Connect

    Calm, J.M.

    1998-08-01

    The Refrigerant Database is an information system on alternative refrigerants, associated lubricants, and their use in air conditioning and refrigeration. It consolidates and facilitates access to property, compatibility, environmental, safety, application and other information. It provides corresponding information on older refrigerants, to assist manufactures and those using alternative refrigerants, to make comparisons and determine differences. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern. The database provides bibliographic citations and abstracts for publications that may be useful in research and design of air-conditioning and refrigeration equipment. The complete documents are not included, though some may be added at a later date. The database identifies sources of specific information on many refrigerants including propane, ammonia, water, carbon dioxide, propylene, ethers, and others as well as azeotropic and zeotropic blends of these fluids. It addresses lubricants including alkylbenzene, polyalkylene glycol, polyolester, and other synthetics as well as mineral oils. It also references documents addressing compatibility of refrigerants and lubricants with metals, plastics, elastomers, motor insulation, and other materials used in refrigerant circuits. Incomplete citations or abstracts are provided for some documents. They are included to accelerate availability of the information and will be completed or replaced in future updates.

  14. Chemically assisted mechanical refrigeration process

    DOEpatents

    Vobach, Arnold R. (6006 Allentown Dr., Spring, TX 77389)

    1987-01-01

    There is provided a chemically assisted mechanical refrigeration process including the steps of: mechanically compressing a refrigerant stream which includes vaporized refrigerant; contacting the refrigerant with a solvent in a mixer (11) at a pressure sufficient to promote substantial dissolving of the refrigerant in the solvent in the mixer (11) to form a refrigerant-solvent solution while concurrently placing the solution in heat exchange relation with a working medium to transfer energy to the working medium, said refrigerant-solvent solution exhibiting a negative deviation from Raoult's Law; reducing the pressure over the refrigerant-solvent solution in an evaporator (10) to allow the refrigerant to vaporize and substantially separate from the solvent while concurrently placing the evolving refrigerant-solvent solution in heat exchange relation with a working medium to remove energy from the working medium to thereby form a refrigerant stream and a solvent stream; and passing the solvent and refrigerant stream from the evaporator.

  15. Chemically assisted mechanical refrigeration process

    DOEpatents

    Vobach, A.R.

    1987-06-23

    There is provided a chemically assisted mechanical refrigeration process including the steps of: mechanically compressing a refrigerant stream which includes vaporized refrigerant; contacting the refrigerant with a solvent in a mixer at a pressure sufficient to promote substantial dissolving of the refrigerant in the solvent in the mixer to form a refrigerant-solvent solution while concurrently placing the solution in heat exchange relation with a working medium to transfer energy to the working medium, said refrigerant-solvent solution exhibiting a negative deviation from Raoult's Law; reducing the pressure over the refrigerant-solvent solution in an evaporator to allow the refrigerant to vaporize and substantially separate from the solvent while concurrently placing the evolving refrigerant-solvent solution in heat exchange relation with a working medium to remove energy from the working medium to thereby form a refrigerant stream and a solvent stream; and passing the solvent and refrigerant stream from the evaporator. 5 figs.

  16. Chemically assisted mechanical refrigeration process

    DOEpatents

    Vobach, A.R.

    1987-11-24

    There is provided a chemically assisted mechanical refrigeration process including the steps of: mechanically compressing a refrigerant stream which includes vaporized refrigerant; contacting the refrigerant with a solvent in a mixer at a pressure sufficient to promote substantial dissolving of the refrigerant in the solvent in the mixer to form a refrigerant-solvent solution while concurrently placing the solution in heat exchange relation with a working medium to transfer energy to the working medium, said refrigerant-solvent solution exhibiting a negative deviation from Raoult's Law; reducing the pressure over the refrigerant-solvent solution in an evaporator to allow the refrigerant to vaporize and substantially separate from the solvent while concurrently placing the evolving refrigerant-solvent solution in heat exchange relation with a working medium to remove energy from the working medium to thereby form a refrigerant stream and a solvent stream; and passing the solvent and refrigerant stream from the evaporator. 5 figs.

  17. Chemically assisted mechanical refrigeration process

    DOEpatents

    Vobach, Arnold R. (6006 Allentown Dr., Spring, TX 77379)

    1987-01-01

    There is provided a chemically assisted mechanical refrigeration process including the steps of: mechanically compressing a refrigerant stream which includes vaporized refrigerant; contacting the refrigerant with a solvent in a mixer (11) at a pressure sufficient to promote substantial dissolving of the refrigerant in the solvent in the mixer (11) to form a refrigerant-solvent solution while concurrently placing the solution in heat exchange relation with a working medium to transfer energy to the working medium, said refrigerant-solvent solution exhibiting a negative deviation from Raoult's Law; reducing the pressure over the refrigerant-solvent solution in an evaporator (10) to allow the refrigerant to vaporize and substantially separate from the solvent while concurrently placing he evolving refrigerant-solvent solution in heat exchange relation with a working medium to remove energy from the working medium to thereby form a refrigerant stream and a solvent stream; and passing the solvent and refrigerant stream from the evaporator.

  18. Analysis of Environmentally Friendly Refrigerant Options for Window Air Conditioners

    SciTech Connect

    Bansal, Pradeep; Shen, Bo

    2015-01-01

    This paper presents a technical assessment of environmentally friendly refrigerants as alternatives to R410A for window air conditioners. The alternative refrigerants that are studied for its replacement include R32, a mixture of R32/R125 with 90%/10% molar concentration, R600a, R290, R1234yf, R1234ze and R134a. Baseline experiments were performed on a window unit charged with R410A. The heat pump design model (HPDM) was modified and calibrated with the baseline data and was used to evaluate the comparative performance of the WAC with alternative refrigerants. The paper discusses the advantages and disadvantages of each refrigerants and their suitability for window air conditioners. Among all the refrigerants studied, R32 offers the best efficiency and the lowest Global Warming Potential (GWP), and hence its use will result in the overall environmental friendliness.

  19. Assessment of Environmentally Friendly Refrigerants for Window Air Conditioners

    SciTech Connect

    Bansal, Pradeep; Shen, Bo

    2014-01-01

    This paper presents technical assessment of environmentally friendly refrigerants for window air conditioners that currently use refrigerant R410A for residential and commercial applications. The alternative refrigerants that are studied for its replacement include R32, R600a, R290, R1234yf, R1234ze and a mixture of R32 (90% molar concentration) and R125 (10% molar concentration). Baseline experiments were performed on a window unit charged with R410A. The ORNL Heat Pump Design Model was calibrated with the baseline data and was used to assess the comparative performance of the WAC with alternative refrigerants. The paper discusses the advantages and disadvantages of each refrigerants and their suitability for window air conditioners.

  20. Listeria monocytogenes survival in refrigerator dill pickles.

    PubMed

    Kim, Jin Kyung; D'Sa, Elaine M; Harrison, Mark A; Harrison, Judy A; Andress, Elizabeth L

    2005-11-01

    Listeria monocytogenes can survive and grow in refrigerated foods with pH values of approximately 4.0 to 5.0 and salt concentrations of 3 to 4%. Home-fermented refrigerator dill pickles fit this description. Contamination of this product with L. monocytogenes could cause serious problems because these items are not heated prior to consumption. L. monocytogenes survival and growth patterns were investigated in refrigerator dill pickles at 1.3, 3.8, and 7.6% salt concentrations. Pickling cucumbers were dipped into an inoculum of L. monocytogenes, brine mixtures were added, and cucumbers were held at room temperature for 1 week and then refrigerated for up to 3 months. The pH, NaCl percentage, titratable acidity percentage, and total populations of Listeria and aerobic, psychrotrophic, and lactic acid bacteria were measured at the addition of brine, after 2, 4, and 7 days of storage at room temperature, and then weekly during refrigerated storage. The initial Listeria population was 5.4 to 5.6 log CFU/cm2 on cucumber surfaces and 3.9 to 4.6 log CFU/g internally. There was an approximate 0.3- to 1-log increase during room temperature fermentation followed by a population decline during refrigerator storage, with a greater decrease in the brines with the highest NaCl concentration. Up to 49 days, the internal tissue of pickles with 1.3, 3.8, or 7.6% salt concentrations were presumptively positive for L. monocytogenes by the enrichment method, and at 91 days the surfaces of such pickles were still positive for L. monocytogenes. Populations of total aerobes and lactic acid bacteria increased during room temperature storage and decreased gradually during refrigerated storage. PMID:16300073

  1. Optimal synthesis of refrigeration cycles and selection of refrigerants

    SciTech Connect

    Vaidyaraman, S.; Maranas, C.D.

    1999-05-01

    The optimal synthesis of the refrigeration configuration and the selection of the best refrigerants that satisfy a set of process cooling duties at different temperatures is addressed. This approach simultaneously selects refrigerants and synthesizes refrigeration structures by minimizing a weighted sum of investment and operating costs. A superstructure representation considers the majority of refrigeration cycle features encountered in real complex multistage refrigeration cycles such as economizers, multiple refrigerants, and heat integration. A novel theoretical treatment of modeling representations and algorithmic improvements is introduced. Results, for example, involving multiple refrigerants, cooling loads, and heat sinks are obtained. Complex, nonintuitive topologies typically emerge as the optimal refrigeration configurations that are better than those obtained when refrigeration synthesis is performed after refrigerant selection.

  2. Near azeotropic mixture substitute

    NASA Technical Reports Server (NTRS)

    Jones, Jack A. (Inventor)

    1996-01-01

    The present invention comprises a refrigerant mixture consisting of a first mole fraction of 1,1,1,2-tetrafluoroethane (R134a) and a second mole fraction of a component selected from the group consisting of a mixture of CHClFCF.sub.3 (R124) and CH.sub.3 CClF.sub.2 (R142b); a mixture of CHF.sub.2 CH.sub.3 (R152a) and CHClFCF.sub.3 (R124); a mixture of CHF.sub.2 CH.sub.3 (R152a) and CH.sub.3 CClF.sub.2 (R142b); and a mixture of CHClFCF.sub.3 (R124), CH.sub.3 CClF.sub.2 (R142b) and CHF.sub.2 CH.sub.3 (R152a).

  3. An evaluation on the environmental consequences of residual CFCs from obsolete household refrigerators in China

    SciTech Connect

    Zhao Xiangyang; Duan Huabo; Li Jinhui

    2011-03-15

    Chlorofluorocarbons (CFCs) contained in household refrigerators consist mainly of CFC-11 and CFC-12, which will be eventually released into the environment. Consequentially, environmental releases of these refrigerants will lead to ozone depletion and contribute significantly to the greenhouse effect, if waste refrigerators are not disposed of properly. In the present paper, the potential release of residual CFCs and their substitutes from obsolete household refrigerators in China is examined, and their contributions to ozone depletion and greenhouse effect are compared with those of other recognized ozone-depleting substances (ODS) and greenhouse gases (GHGs). The results imply that annual potential amounts of released residual CFC-11 and CFC-12 will reach their maximums at 4600 and 2300 tons, respectively in 2011, and then decrease gradually to zero until 2020. Meanwhile, the amounts of their most widely used substitutes HCFC-141b and HFC-134a will keep increasing. Subsequently, the contribution ratio of these CFCs and their substitutes to ozone depletion will remain at 25% through 2011, and reach its peak value of 34% by 2018. The contribution to greenhouse effect will reach its peak value of 0.57% by 2010. Moreover, the contribution ratio of these CFCs to the total global release of CFCs will steadily increase, reaching its peak of 15% by 2018. Thus, this period from 2010 to 2018 is a crucial time during which residual CFCs and their substitutes from obsolete household refrigerators in China will contribute significantly to ozone depletion.

  4. Thermoacoustic engines and refrigerators

    NASA Astrophysics Data System (ADS)

    Garrett, Steven L.

    2012-06-01

    Thermoacoustic engines and refrigerators use gas inertia and compressibility to eliminate many of the mechanical contrivances required by traditional engines and refrigerators while providing potentially attractive options that might reduce environmental impacts. The operation of both standing-wave and traveling-wave devices will be described and illustrated with thermoacoustic devices that have been used outside the laboratory.

  5. ARTI Refrigerant Database

    SciTech Connect

    Calm, J.M.

    1992-04-30

    The Refrigerant Database consolidates and facilitates access to information to assist industry in developing equipment using alternative refrigerants. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern. The database provides bibliographic citations and abstracts for publications that may be useful in research and design of air- conditioning and refrigeration equipment. The complete documents are not included, though some may be added at a later date. The database identifies sources of specific information on R-32, R-123, R-124, R- 125, R-134a, R-141b, R142b, R-143a, R-152a, R-290 (propane), R-717 (ammonia), ethers, and others as well as azeotropic and zeotropic blends of these fluids. It addresses polyalkylene glycol (PAG), ester, and other lubricants. It also references documents addressing compatibility of refrigerants and lubricants with metals, plastics, elastomers, motor insulation, and other materials used in refrigerant circuits.

  6. Evidence for under-reported western European emissions of the potent greenhouse gas HFC-23

    NASA Astrophysics Data System (ADS)

    Keller, Christoph A.; Brunner, Dominik; Henne, Stephan; Vollmer, Martin K.; O'Doherty, Simon; Reimann, Stefan

    2011-08-01

    Western European emission inventories of the potent greenhouse gas trifluoromethane (HFC-23) are validated at a country level by combining 2-hourly atmospheric in-situ measurements at Jungfraujoch (Switzerland) and Mace Head (Ireland) with Lagrangian transport simulations. HFC-23 has an atmospheric lifetime of ˜270 yr and a 100-yr global warming potential (GWP) of 14,800 and is unintentionally produced during the manufacture of chlorodifluoromethane (HCFC-22). For the study region we derive emissions of 144-216 Mg/yr for July 2008-July 2010, which are 60-140% higher than the official emissions gathered from the national reports for the year 2009. The largest discrepancy is found for Italy, where our estimate of 26-56 Mg/yr exceeds the national inventory (2.6 Mg/yr) by more than an order of magnitude. These findings suggest that non-reported emissions from Annex 1 countries partly explain the recently derived gap between global bottom-up and top-down HFC-23 emission estimates. The results presented here provide independent information to relevant authorities on effective reporting of HFC-23 emissions, and demonstrate the potential of atmospheric measurements for real-world verification of greenhouse gas emissions.

  7. HEAT TRANSFER EVALUATION OF HFC-236EA WITH HIGH PERFORMANCE ENHANCED TUBES IN CONDENSATION AND EVAPORATION

    EPA Science Inventory

    The report gives results of an evaluation of the heat transfer performance of pure hydrofluorocarbon (HFC)-236ea for high performance enhanced tubes which had not been previously used in Navy shipboard chillers. Shell-side heat transfer coefficient data are presented for condensa...

  8. HEAT TRANSFER EVALUATION OF HFC-236EA WITH HIGH PERFORMANCE ENHANCED TUBES IN CONDENSATION AND EVAPORATION

    EPA Science Inventory

    The report gives results of an evaluation of the heat transfer performance of pure hydrofluorocarbon (HFC)-236ea for high performance enhanced tubes which had not been previously used in Navy shipboard chillers. Shell-side heat transfer coefficient data are presented for conde...

  9. HEAT TRANSFER EVALUATION OF HFC-236FA IN CONDENSATION AND EVAPORATION

    EPA Science Inventory

    The report gives results of an evaluation of the shell-side heat transfer performance of hydrofluorocarbon (HFC)-236fa, which is considered to be a potential substitute for chlorofluorocarbon (CFC)-114 in Navy shipboard chillers, for both conventional finned (1024- and 1575-fpm (...

  10. HEAT TRANSFER EVALUATION OF HFC-236FA IN CONDENSATION AND EVAPORATION

    EPA Science Inventory

    The report gives results of an evaluation of the shell-side heat transfer performance of hydrofluorocarbon (HFC)-236fa, which is considered to be a potential substitute for chlorofluorocarbon (CFC)-114 in Navy shipboard chillers, for both conventional finned [1024- and 1575-fpm (...

  11. Pulse Tube Refrigerator

    NASA Astrophysics Data System (ADS)

    Matsubara, Yoichi

    The pulse tube refrigerator is one of the regenerative cycle refrigerators such as Stirling cycle or Gifford-McMahon cycle which gives the cooling temperature below 150 K down to liquid helium temperature. In 1963, W. E. Gifford invented a simple refrigeration cycle which is composed of compressor, regenerator and simple tube named as pulse tube which gives a similar function of the expander in Stirling or Gifford-McMahon cycle. The thermodynamically performance of this pulse tube refrigerator is inferior to that of other regenerative cycles. In 1984, however, Mikulin and coworkers made a significant advance in pulse tube configuration called as orifice pulse tube. After this, several modifications of the pulse tube hot end configuration have been developed. With those modifications, the thermodynamic performance of the pulse tube refrigerator became the same order to that of Stirling and Gifford-McMahon refrigerator. This article reviews the brief history of the pulse tube refrigerator development in the view point of its thermodynamically efficiency. Simplified theories of the energy flow in the pulse tube have also been described.

  12. THERMODYNAMIC PERFORMANCE LIMIT AND EVAPORATOR DESIGN CONSIDERATIONS FOR NARM-BASED DOMESTIC REFRIGERATOR-FREEZER SYSTEMS

    EPA Science Inventory

    The paper gives results of an investigation of non-azeotrophic refrigerant mixtures (NARMs) for a two-temperature-level heat exchange process found in a domestic refrigerator-freezer. deal (constant air temperature) heat exhcange processes are assumed. he results allow the effect...

  13. Miniature thermoacoustic refrigerator

    NASA Astrophysics Data System (ADS)

    Symko, Orest G.

    1994-04-01

    A miniature thermoacoustic refrigerator was developed for cooling electronic components. The refrigerator is driven at 5,000 Hz by a piezoelectric driver and it consists of an acoustic resonator, a stack, and copper heat exchangers. The working fluid is pressurized helium gas between 10 to 20 atmospheres. Sound was produced with different piezoelectric drivers, a monomorph, a bimorph, and Tonpilz driver to achieve the highest intensity possible. Since the operating frequency is high, the refrigerator is compact, being about 10 cm long. Temperature differences of 12 C across the stack were achieved at sound levels of 160 dB. The performance of the refrigerator scaled with frequency according to existing models of thermoacoustic heat engines.

  14. Thermoacoustic engines and refrigerators

    SciTech Connect

    Swift, G.

    1996-12-31

    This report is a transcript of a practice lecture given in preparation for a review lecture on the operation of thermoacoustic engines and refrigerators. The author begins by a brief review of the thermodynamic principles underlying the operation of thermoacoustic engines and refrigerators. Remember from thermodynamics class that there are two kinds of heat engines, the heat engine or the prime mover which produces work from heat, and the refrigerator or heat pump that uses work to pump heat. The device operates between two thermal reservoirs at temperatures T{sub hot} and T{sub cold}. In the heat engine, heat flows into the device from the reservoir at T{sub hot}, produces work, and delivers waste heat into the reservoir at T{sub cold}. In the refrigerator, work flows into the device, lifting heat Q{sub cold} from reservoir at T{sub cold} and rejecting waste heat into the reservoir at T{sub hot}.

  15. Control of refrigerant vapor release from polyol ester/halocarbon working fluids

    SciTech Connect

    Swallow, A.P.; Smith, A.M.; Greig, B.

    1995-12-31

    New synthetic polyol ester compressor lubricants have been developed primarily for use with hydrofluorocarbon refrigerants. Since their introduction in 1989, these lubricants have been shown to be satisfactory for the new working fluids in virtually all compressor designs and applications. A major application area for polyol ester lubrication over this period has been as retrofill lubricants for conversion of existing CFC or HCFC systems to HFC refrigerants. Synthetic polyol ester lubricants, unlike refined mineral oils, are very pure man-made products. A consequence of the high purity of polyol ester lubricants is that the outgassing rate of dissolved refrigerant is significantly higher than that for mineral oils. The increased rate of outgassing can result in lubrication failure of the compressor caused by vapor lock of the oil pump or degreasing of contact surfaces. Such a situation may occur, for example, at start up of the compressor or during normal operation, in multicompressor split systems, liquid injection, or internally compounded compressors. Problems caused by outgassing of refrigerant can be overcome at the OEM level by redesign of the compressor for new systems using ester oil. However, compressor design changes are often not a viable option for existing compressors that still have a long potential life and will be eligible for retrofill conversion. This paper details some of the potential retrofill problem areas and demonstrates an inexpensive solution by a simple change in synthetic ester lubricant properties.

  16. Refrigeration and Air-Conditioning Technology Workshop

    NASA Astrophysics Data System (ADS)

    Lewis, P. J.; Counce, D. M.

    1993-12-01

    The Alternative Fluorocarbon Environmental Acceptability Study (AFEAS), a consortium of fluorocarbon manufacturers, and the U.S. Department of Energy (DOE) are collaborating on a project to evaluate the energy use and global warming impacts of CFC alternatives. The goal of this project is to identify technologies that could replace the use of CFC's in refrigeration, heating, and air-conditioning equipment; to evaluate the direct impacts of chemical emissions on global warming; and to compile accurate estimates of energy use and indirect CO2 emissions of substitute technologies. The first phase of this work focused on alternatives that could be commercialized before the year 2000. The second phase of the project is examining not-in-kind and next-generation technologies that could be developed to replace CFC's, HCFC's, and HFC's over a longer period. As part of this effort, Oak Ridge National Laboratory held a workshop on June 23-25, 1993. The preliminary agenda covered a broad range of alternative technologies and at least one speaker was invited to make a brief presentation at the workshop on each technology. Some of the invited speakers were unable to participate, and in a few cases other experts could not be identified. As a result, those technologies were not represented at the workshop. Each speaker was asked to prepare a five to seven page paper addressing six key issues concerning the technology he/she is developing. These points are listed in the sidebar. Each expert also spoke for 20 to 25 minutes at the workshop and answered questions from the other participants concerning the presentation and area of expertise. The primary goal of the presentations and discussions was to identify the developmental state of the technology and to obtain comparable data on system efficiencies.

  17. The effect of refrigerants in the mixed lubrication regime

    SciTech Connect

    Mizuhara, Kazuyuki; Tomimoto, Makoto

    1997-12-31

    Because of environmental concerns, CFC (chlorofluorocarbon) refrigerants must be replaced with HFCs (hydrofluorocarbons). As a result, many tribological problems are caused especially in rotary piston compressors. To solve the problem, the effects of refrigerants on friction and wear characteristics of the oil and refrigerant mixtures at the mixed lubrication regime are investigated. The difference in refrigerants are clearly observed not only in boundary but also in the mixed lubrication regime. The effects of operating conditions on sliding conditions and experimental results are also discussed. It is concluded that for practical application where long life is essential, experiments must be conducted under the mixed lubrication regime. Also, the importance of defining the lubrication regime in terms of film parameter is emphasized.

  18. The Effect of Modified Atmosphere Packaging and Addition of Rosemary Extract, Sodium Acetate and Calcium Lactate Mixture on the Quality of Pre-cooked Hamburger Patties during Refrigerated Storage

    PubMed Central

    Muhlisin; Kang, Sun Moon; Choi, Won Hee; Lee, Keun Taik; Cheong, Sung Hee; Lee, Sung Ki

    2013-01-01

    The effect of modified atmosphere packaging (MAP; 30% CO2+70% N2 or 100% N2) and an additive mixture (500 ppm rosemary extract, 3,000 ppm sodium acetate and 1,500 ppm calcium lactate) on the quality of pre-cooked hamburger patties during storage at 5°C for 14 d was evaluated. The addition of the additive mixture reduced aerobic and anaerobic bacteria counts in both 30% CO2-MAP (30% CO2+70% N2) and 100% N2-MAP (p<0.05). The 30% CO2-MAP was more effective to suppress the microbial growth than 100% N2-MAP, moreover the 30% CO2-MAP combined with additive mixture resulted in the lowest bacterial counts. The hamburger patties with additive mixture showed lower CIE L* and CIE a*, and higher CIE b* than those with no additive mixture. The 30% CO2-MAP tended to decrease the TBARS during storage regardless of the addition of additives. The use of 30% CO2-MAP in combination with additives mixture was effective for maintaining the quality and extending the shelf-life of pre-cooked hamburger patties. PMID:25049716

  19. 21 CFR 1250.34 - Refrigeration equipment.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...Land and Air Conveyances, and Vessels § 1250.34 Refrigeration equipment. Each refrigerator shall be equipped with a thermometer located in the warmest portion thereof. Waste water drains from ice boxes, refrigerating equipment, and refrigerated...

  20. 21 CFR 1250.34 - Refrigeration equipment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Land and Air Conveyances, and Vessels § 1250.34 Refrigeration equipment. Each refrigerator shall be equipped with a thermometer located in the warmest portion thereof. Waste water drains from ice boxes, refrigerating equipment, and refrigerated...

  1. 21 CFR 1250.34 - Refrigeration equipment.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...Land and Air Conveyances, and Vessels § 1250.34 Refrigeration equipment. Each refrigerator shall be equipped with a thermometer located in the warmest portion thereof. Waste water drains from ice boxes, refrigerating equipment, and refrigerated...

  2. ARTI Refrigerant Database

    SciTech Connect

    Cain, J.M.

    1993-04-30

    The Refrigerant Database consolidates and facilitates access to information to assist industry in developing equipment using alternative refrigerants. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern. The database provides bibliographic citations and abstracts for publications that may be useful in research and design of air-conditioning and refrigeration equipment. The complete documents are not included. The database identifies sources of specific information on R-32, R-123, R-124, R-125, R-134, R-134a, R-141b, R-142b, R-143a, R-152a, R-245ca, R-290 (propane), R-717 (ammonia), ethers, and others as well as azeotropic and zeotropic blends of these fluids. It addresses lubricants including alkylbenzene, polyalkylene glycol, ester, and other synthetics as well as mineral oils. It also references documents addressing compatibility of refrigerants and lubricants with metals, plastics, elastomers, motor insulation, and other materials used in refrigerant circuits. Incomplete citations or abstracts are provided for some documents to accelerate availability of the information and will be completed or replaced in future updates.

  3. Downhole pulse tube refrigerators

    SciTech Connect

    Swift, G.; Gardner, D.

    1997-12-01

    This report summarizes a preliminary design study to explore the plausibility of using pulse tube refrigeration to cool instruments in a hot down-hole environment. The original motivation was to maintain Dave Reagor`s high-temperature superconducting electronics at 75 K, but the study has evolved to include three target design criteria: cooling at 30 C in a 300 C environment, cooling at 75 K in a 50 C environment, cooling at both 75 K and 30 C in a 250 C environment. These specific temperatures were chosen arbitrarily, as representative of what is possible. The primary goals are low cost, reliability, and small package diameter. Pulse-tube refrigeration is a rapidly growing sub-field of cryogenic refrigeration. The pulse tube refrigerator has recently become the simplest, cheapest, most rugged and reliable low-power cryocooler. The authors expect this technology will be applicable downhole because of the ratio of hot to cold temperatures (in absolute units, such as Kelvin) of interest in deep drilling is comparable to the ratios routinely achieved with cryogenic pulse-tube refrigerators.

  4. Waste Heat Recovery from Refrigeration 

    E-print Network

    Jackson, H. Z.

    1982-01-01

    heat recovery from refrigeration machines is a concept which has great potential for implementation in many businesses. If a parallel requirement for refrigeration and hot water exists, the installation of a system to provide hot water as a by...

  5. ARTI Refrigerant Database

    SciTech Connect

    Calm, J.M.

    1992-11-09

    The database provides bibliographic citations and abstracts for publications that may be useful in research and design of air- conditioning and refrigeration equipment. The database identifies sources of specific information on R-32, R-123, R-124, R-125, R-134, R-134a, R-141b, R-142b, R-143a, R-152a, R-245ca, R-290 (propane), R- 717 (ammonia), ethers, and others as well as azeotropic and zeotropic and zeotropic blends of these fluids. It addresses lubricants including alkylbenzene, polyalkylene glycol, ester, and other synthetics as well as mineral oils. It also references documents on compatibility of refrigerants and lubricants with metals, plastics, elastomers, motor insulation, and other materials used in refrigerant circuits. A computerized version is available that includes retrieval software.

  6. Adsorption Refrigeration System

    SciTech Connect

    Wang, Kai; Vineyard, Edward Allan

    2011-01-01

    Adsorption refrigeration is an environmentally friendly cooling technology which could be driven by recovered waste heat or low-grade heat such as solar energy. In comparison with absorption system, an adsorption system has no problems such as corrosion at high temperature and salt crystallization. In comparison with vapor compression refrigeration system, it has the advantages of simple control, no moving parts and less noise. This paper introduces the basic theory of adsorption cycle as well as the advanced adsorption cycles such as heat and mass recovery cycle, thermal wave cycle and convection thermal wave cycle. The types, characteristics, advantages and drawbacks of different adsorbents used in adsorption refrigeration systems are also summarized. This article will increase the awareness of this emerging cooling technology among the HVAC engineers and help them select appropriate adsorption systems in energy-efficient building design.

  7. Japanese refrigerators field testing

    SciTech Connect

    Lou, A.T.

    1989-03-01

    Residential refrigerators consume the equivalent of 1700 megawatts (MW) of baseload power in the Bonneville Power Administration (BPA) service area. Japanese manufacturers have designed refrigerator units that appear more energy efficient than some currently available American models. This report summarizes preliminary findings from field testing of 12 refrigerators of Japanese manufacture to evaluate annual kilowatt hour (kWh) use during actual operation. The units have also undergone laboratory testing sponsored by BPA at ETL Testing Laboratories, Inc. in Cortland, New York. A final report of the project -- due at the end of 1989 -- will correlate in detail the results of field and laboratory tests in comparison to performance ratings determined by the manufacturer.

  8. Japanese Refrigerators Field Testing.

    SciTech Connect

    Lou, Albert T.

    1989-03-01

    Residential refrigerators consume the equivalent of 1700 megawatts (MW) of baseload power in the Bonneville Power Administration (BPA) service area. Japanese manufacturers have designed refrigerator units that appear more energy efficient than some currently available American models. This report summarizes preliminary findings from field testing of 12 refrigerators of Japanese manufacture to evaluate annual kilowatt hour (kWh) use during actual operation. The units have also undergone laboratory testing sponsored by BPA at ETL Testing Laboratories, Inc. in Cortland, New York. A final report of the project -- due at the end of 1989 -- will correlate in detail the results of field and laboratory tests in comparison to performance ratings determined by the manufacturer.

  9. Magnetic refrigeration for spacecraft systems

    SciTech Connect

    Barclay, J.A.

    1981-01-01

    Magnetic refrigerators, i.e., those that use the magnetocaloric effect of a magnetic working material in a thermodynamic cycle, offer potentially reliable, and efficient refrigeration over a variety of temperature ranges and cooling powers. A descriptive analysis of magnetic refrigeration systems is performed with particular emphasis on more efficient infrared detector cooling. Three types of magnetic refrigerator designs are introduced to illustrate some of the possibilities.

  10. Investigation of pressure drop in capillary tube for mixed refrigerant Joule-Thomson cryocooler

    SciTech Connect

    Ardhapurkar, P. M.; Sridharan, Arunkumar; Atrey, M. D.

    2014-01-29

    A capillary tube is commonly used in small capacity refrigeration and air-conditioning systems. It is also a preferred expansion device in mixed refrigerant Joule-Thomson (MR J-T) cryocoolers, since it is inexpensive and simple in configuration. However, the flow inside a capillary tube is complex, since flashing process that occurs in case of refrigeration and air-conditioning systems is metastable. A mixture of refrigerants such as nitrogen, methane, ethane, propane and iso-butane expands below its inversion temperature in the capillary tube of MR J-T cryocooler and reaches cryogenic temperature. The mass flow rate of refrigerant mixture circulating through capillary tube depends on the pressure difference across it. There are many empirical correlations which predict pressure drop across the capillary tube. However, they have not been tested for refrigerant mixtures and for operating conditions of the cryocooler. The present paper assesses the existing empirical correlations for predicting overall pressure drop across the capillary tube for the MR J-T cryocooler. The empirical correlations refer to homogeneous as well as separated flow models. Experiments are carried out to measure the overall pressure drop across the capillary tube for the cooler. Three different compositions of refrigerant mixture are used to study the pressure drop variations. The predicted overall pressure drop across the capillary tube is compared with the experimentally obtained value. The predictions obtained using homogeneous model show better match with the experimental results compared to separated flow models.

  11. Investigation of pressure drop in capillary tube for mixed refrigerant Joule-Thomson cryocooler

    NASA Astrophysics Data System (ADS)

    Ardhapurkar, P. M.; Sridharan, Arunkumar; Atrey, M. D.

    2014-01-01

    A capillary tube is commonly used in small capacity refrigeration and air-conditioning systems. It is also a preferred expansion device in mixed refrigerant Joule-Thomson (MR J-T) cryocoolers, since it is inexpensive and simple in configuration. However, the flow inside a capillary tube is complex, since flashing process that occurs in case of refrigeration and air-conditioning systems is metastable. A mixture of refrigerants such as nitrogen, methane, ethane, propane and iso-butane expands below its inversion temperature in the capillary tube of MR J-T cryocooler and reaches cryogenic temperature. The mass flow rate of refrigerant mixture circulating through capillary tube depends on the pressure difference across it. There are many empirical correlations which predict pressure drop across the capillary tube. However, they have not been tested for refrigerant mixtures and for operating conditions of the cryocooler. The present paper assesses the existing empirical correlations for predicting overall pressure drop across the capillary tube for the MR J-T cryocooler. The empirical correlations refer to homogeneous as well as separated flow models. Experiments are carried out to measure the overall pressure drop across the capillary tube for the cooler. Three different compositions of refrigerant mixture are used to study the pressure drop variations. The predicted overall pressure drop across the capillary tube is compared with the experimentally obtained value. The predictions obtained using homogeneous model show better match with the experimental results compared to separated flow models.

  12. Refrigerants in Transition 

    E-print Network

    Stouppe, D. E.

    1991-01-01

    needs to be maintained in leak-free condition. The purge systems of sub-atmospheric operating systems need to be correctly operated and in good operating condition, and the serviceperson needs to contain the refrigerant either in the system during... feet high to produce the static pressure necessary to compress the refrigerant. DEALl~CWITH EXISTING SYSTEMS It is estimated that 25% of the CFC-11 used in the United States is lost to the atmosphere annually through leaks, improper or inoperative purge...

  13. Comprehensive Compressor Calorimeter Testing of Lower-GWP Alternative Refrigerants for Heat Pump and Medium Temperature Refrigeration Applications

    SciTech Connect

    Shrestha, Som S; Sharma, Vishaldeep; Abdelaziz, Omar

    2014-01-01

    In response to environmental concerns raised by the use of refrigerants with high Global Warming Potential (GWP), the Air-Conditioning, Heating, and Refrigeration Institute (AHRI) has launched an industry-wide cooperative research program, referred to as the Low-GWP Alternative Refrigerants Evaluation Program (AREP), to identify and evaluate promising alternative refrigerants for major product categories. This paper reports one of the Oak Ridge National Laboratory (ORNL) contributions to AREP. It compares performance of alternative refrigerants to that of R-410A and R-404A for heat pump and medium temperature applications, respectively. The alternatives reported in this paper are: R-32, DR-5, and L-41a for R-410A and ARM-31a, D2Y-65, L-40, and a mixture of R-32 and R-134a for R-404A. All performance comparison tests were conducted using scroll compressors of ~1.85 tons (6.5 kW) cooling capacity. Tests were conducted over a range of combinations of saturation suction and saturation discharge temperatures for both compressors. The tests showed that, in general, energy efficiency ratio (EER) and cooling capacity of R-410A alternative refrigerants were slightly lower than that of the baseline refrigerant with a moderate increases in discharge temperature. On the other hand, R-404A alternative refrigerants showed relative performance dependence on saturation suction and saturation discharge temperatures and larger increases in discharge temperature than for the R-410A alternatives. This paper summarizes the relative performance of all alternative refrigerants compared to their respective baseline.

  14. MOBILE AIR CONDITIONER REFRIGERANT EVALUATION

    EPA Science Inventory

    The paper discusses an evaluation of refrigerant from mobile air conditioners. The data gathered indicate that CFC-l2 refrigerant does not degrade significantly with use. Furthermore, while small amounts of contaminant are removed with the refrigerant during servicing, most of th...

  15. Low-temperature magnetic refrigerator

    DOEpatents

    Barclay, J.A.

    1983-05-26

    The invention relates to magnetic refrigeration and more particularly to low temperature refrigeration between about 4 and about 20 K, with an apparatus and method utilizing a belt of magnetic material passed in and out of a magnetic field with heat exchangers within and outside the field operably disposed to accomplish refrigeration.

  16. Status Of Sorption Cryogenic Refrigeration

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.

    1988-01-01

    Report reviews sorption refrigeration. Developed for cooling infrared detectors, cryogenic research, and other advanced applications, sorption refrigerators have few moving parts, little vibration, and lifetimes of 10 years or more. Describes types of sorption stages, multistage and hybrid refrigeration systems, power requirements, cooling capacities, and advantages and disadvantages of various stages and systems.

  17. Exergy analysis of magnetic refrigeration

    E-print Network

    Lucia, Umberto

    2010-01-01

    One of the main challenges of the industry today is to face its impact on global warming considering that the greenhouse effect problem is not be solved completely yet. Magnetic refrigeration represents an environment-safe refrigeration technology. The magnetic refrigeration is analysed using the second law analysis and introducing exergy in order to obtain a model for engineering application.

  18. Refrigeration Playbook: Natural Refrigerants; Selecting and Designing Energy-Efficient Commercial Refrigeration Systems That Use Low Global Warming Potential Refrigerants

    SciTech Connect

    Nelson, Caleb; Reis, Chuck; Nelson, Eric; Armer, James; Arthur, Rob; Heath, Richard; Rono, James; Hirsch, Adam; Doebber, Ian

    2015-03-01

    This report provides guidance for selecting and designing energy efficient commercial refrigeration systems using low global warming potential refrigerants. Refrigeration systems are generally the largest energy end use in a supermarket type building, often accounting for more than half of a building's energy consumption.

  19. EFFECT OF RE-HEATING ON VIABILITY OF A 5-STRAIN MIXTURE OF L. MONOCYTOGENES IN VACUUM-SEALED PKGS OF FRANKFURTERS,COMMERCIALLY PREPARED WITH AND WITHOUT 2.0% POTASSIUM LACTATE, FOLLOWING REFRIGERATED OR FROZEN STORAGE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of this study was to assess the effect of product formulation and storage times and temperatures on the viability of Listeria monocytogenes after re-heating of frankfurters. Individual links were inoculated with about 8.0 log10 CFU/package of a five-strain mixture of the pathogen, vacuu...

  20. Study to determine the existence of an azeotropic R-22 `drop-in` substitute

    SciTech Connect

    Kim, M.S.; Morrison, G.; Mulroy, W.J.; Didion, D.A.

    1996-03-01

    The reduction in chlorofluorocarbon (CFC) and hydrochlorofluorocarbon (HCFC) production and the scheduled phase-out of these ozone depleting refrigerants requires the development and determination of environmentally safe refrigerants for use in heat pumps, water chillers, air conditioners, and refrigerators. Azeotropic mixtures are attractive as alternative refrigerants because they behave very nearly as pure materials. A simple correlative scheme that allows one to judge whether or not an azeotrope is likely in a binary refrigerant mixture is discussed. This paper presents laboratory and computer simulation model evaluation of two of the azeotropic refrigerant mixtures which are identified, HFC-134a (1,1,1,2-tetrafluoroethane) with R-C290 (Propane) and HFC-134a with R-600a (Isobutane), in a generic heat pump apparatus. A third azeotropes mixture, HFC-134a with R-C290 (Cyclopropane) is examined by computer simulation only.

  1. Dilution refrigeration for space applications

    NASA Technical Reports Server (NTRS)

    Israelsson, U. E.; Petrac, D.

    1990-01-01

    Dilution refrigerators are presently used routinely in ground based applications where temperatures below 0.3 K are required. The operation of a conventional dilution refrigerator depends critically on the presence of gravity. To operate a dilution refrigerator in space many technical difficulties must be overcome. Some of the anticipated difficulties are identified in this paper and possible solutions are described. A single cycle refrigerator is described conceptually that uses forces other than gravity to function and the stringent constraints imposed on the design by requiring the refrigerator to function on the earth without using gravity are elaborated upon.

  2. Compact Refrigerator Rfrigerateur Compact

    E-print Network

    Serianni, Anthony S.

    the possibility of danger to children. 8) After your refrigerator is in operation, do not touch the cold surfaces, poultry, or fish that have any off-odor or off-color should not be refrozen and should not be eaten it. The food may be dangerous to eat. 1 English SAFETY PRECAUTIONS #12;Thank you for using our Haier

  3. Thermoacoustic engines and refrigerators

    SciTech Connect

    Swift, G.W.

    1995-07-01

    We ordinarily think of a sound wave in a gas as consisting of coupled pressure and displacement oscillations. However, temperature oscillations always accompany the pressure changes. The combination of all these oscillations, and their interaction with solid boundaries, produces a rich variety of `thermoacoustic` effects. Although these effects as they occur in every-day life are too small to be noticed, one can harness extremely loud sound waves in acoustically sealed chambers to produce powerful heat engines, heat pumps and refrigerators. Whereas typical engines and refrigerators have crankshaft-coupled pistons or rotating turbines, thermoacoustic engines and refrigerators have at most a single flexing moving part (as in a loudspeaker) with no sliding seals. Thermoacoustic devices may be of practical use where simplicity, reliability or low cost is more important than the highest efficiency (although one cannot say much more about their cost-competitiveness at this early stage). This paper discusses the fundamentals of thermoacoustic engines and refrigerators, research in this field, and their commercial development. 16 refs., 5 figs.

  4. Education in Helium Refrigeration

    SciTech Connect

    Gistau Baguer, G. M.

    2004-06-23

    On the one hand, at the end of the time I was active in helium refrigeration, I noticed that cryogenics was stepping into places where it was not yet used. For example, a conventional accelerator, operating at room temperature, was to be upgraded to reach higher particle energy. On the other hand, I was a little bit worried to let what I had so passionately learned during these years to be lost. Retirement made time available, and I came gradually to the idea to teach about what was my basic job. I thought also about other kinds of people who could be interested in such lessons: operators of refrigerators or liquefiers who, often by lack of time, did not get a proper introduction to their job when they started, young engineers who begin to work in cryogenics... and so on.Consequently, I have assembled a series of lessons about helium refrigeration. As the audiences have different levels of knowledge in the field of cryogenics, I looked for a way of teaching that is acceptable for all of them. The course is split into theory of heat exchangers, refrigeration cycles, technology and operation of main components, process control, and helium purity.

  5. Fundamentals of Refrigeration.

    ERIC Educational Resources Information Center

    Sutliff, Ronald D.; And Others

    This self-study course is designed to familiarize Marine enlisted personnel with the principles of the refrigeration process. The course contains five study units. Each study unit begins with a general objective, which is a statement of what the student should learn from the unit. The study units are divided into numbered work units, each…

  6. Solar Powered Refrigeration System

    NASA Technical Reports Server (NTRS)

    Ewert, Michael K. (Inventor); Bergeron, David J., III (Inventor)

    2002-01-01

    A solar powered vapor compression refrigeration system is made practicable with thermal storage and novel control techniques. In one embodiment, the refrigeration system includes a photovoltaic panel, a variable speed compressor, an insulated enclosure, and a thermal reservoir. The photovoltaic (PV) panel converts sunlight into DC (direct current) electrical power. The DC electrical power drives a compressor that circulates refrigerant through a vapor compression refrigeration loop to extract heat from the insulated enclosure. The thermal reservoir is situated inside the insulated enclosure and includes a phase change material. As heat is extracted from the insulated enclosure, the phase change material is frozen, and thereafter is able to act as a heat sink to maintain the temperature of the insulated enclosure in the absence of sunlight. The conversion of solar power into stored thermal energy is optimized by a compressor control method that effectively maximizes the compressor's usage of available energy. A capacitor is provided to smooth the power voltage and to provide additional current during compressor start-up. A controller monitors the rate of change of the smoothed power voltage to determine if the compressor is operating below or above the available power maximum, and adjusts the compressor speed accordingly. In this manner, the compressor operation is adjusted to convert substantially all available solar power into stored thermal energy.

  7. Improved cryogenic refrigeration system

    NASA Technical Reports Server (NTRS)

    Higa, W. H.

    1967-01-01

    Two-position shuttle valve simplifies valving arrangement and crank-shaft configuration in gas-balancing and Stirling-cycle refrigeration systems used to produce temperatures below 173 degrees K. It connects the displacer and regenerator alternately to the supply line or the return line of the compressor, and establishes constant pressure on the drive piston.

  8. Comparison of Several Eco-Friendly Refrigeration Technologies 

    E-print Network

    Tang, C.; Luo, Q.; Li, X.; Zhu, X.

    2006-01-01

    In this paper, the operation principles, thermodynamics characteristics, and technical practicability were compared between thermoelectric refrigeration, magnetic refrigeration and adsorption refrigeration. The TE refrigeration is the most well...

  9. Design analysis of the Einstein refrigeration cycle

    SciTech Connect

    Shelton, S.V.; Delano, A.; Schaefer, L.A.

    1999-07-01

    After developing the theory of relativity, Albert Einstein spent several years working with Leo Szilard on absorption refrigeration cycles. In 1930, they obtained a US patent for a unique single pressure absorption cycle. The single pressure eliminates the need for a solution pump. Their cycle has only recently been rediscovered. The cycle utilizes butane as its refrigerant, ammonia as a pressure equalizing fluid, and water as an absorbing fluid. This cycle is dramatically different in both concept and detail than the better-known ammonia-water-hydrogen cycle. In this study, thermodynamic and mixture property models of the Einstein cycle were created to gain insight into the cycle's operating characteristics and to calculate its performance. A conceptual demonstration model was built and successfully operated, showing for the first time the viability of the cycle. The model results found that the system pressure is an important design parameter, with the COP having an optimum when the system pressure is equal to the saturation pressure of the butane refrigerant. It was also found that for a given system pressure, there is a maximum condenser-absorber temperature and a minimum evaporator temperature.

  10. 40 CFR Appendix C to Subpart B of... - SAE J2788 Standard for Recovery/Recycle and Recovery/Recycle/Recharging Equipment for HFC-134a...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...equipment requirements for the recovery/recycling of HFC-134a that has been directly...air-conditioning systems and recovery/recycling and system recharging of recycled...performance requirements for recovery and recycling of HFC-134a that has been...

  11. 40 CFR Appendix C to Subpart B of... - SAE J2788 Standard for Recovery/Recycle and Recovery/Recycle/Recharging Equipment for HFC-134a...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...equipment requirements for the recovery/recycling of HFC-134a that has been directly...air-conditioning systems and recovery/recycling and system recharging of recycled...performance requirements for recovery and recycling of HFC-134a that has been...

  12. Magnetic refrigeration apparatus with belt of ferro or paramagnetic material

    DOEpatents

    Barclay, J.A.; Stewart, W.F.; Henke, M.D.; Kalash, K.E.

    1986-04-03

    A magnetic refrigerator operating in the 12 to 77 K range utilizes a belt which carries ferromagnetic or paramagnetic material and which is disposed in a loop which passes through the center of a solenoidal magnet to achieve cooling. The magnetic material carried by the belt, which can be blocks in frames of a linked belt, can be a mixture of substances with different Curie temperatures arranged such that the Curie temperatures progressively increase from one edge of the belt to the other. This magnetic refrigerator can be used to cool and liquefy hydrogen or other fluids.

  13. Magnetic refrigeration apparatus with belt of ferro or paramagnetic material

    DOEpatents

    Barclay, John A. (Madison, WI); Stewart, Walter F. (Marshall, WI); Henke, Michael D. (Los Alamos, NM); Kalash, Kenneth E. (Los Alamos, NM)

    1987-01-01

    A magnetic refrigerator operating in the 12 to 77K range utilizes a belt which carries ferromagnetic or paramagnetic material and which is disposed in a loop which passes through the center of a solenoidal magnet to achieve cooling. The magnetic material carried by the belt, which can be blocks in frames of a linked belt, can be a mixture of substances with different Curie temperatures arranged such that the Curie temperatures progressively increase from one edge of the belt to the other. This magnetic refrigerator can be used to cool and liquefy hydrogen or other fluids.

  14. Atmospheric degradation mechanisms of hydrogen containing chlorofluorocarbons (HCFC) and fluorocarbons (HFC)

    NASA Technical Reports Server (NTRS)

    Zellner, Reinhard

    1990-01-01

    The current knowledge of atmospheric degradation of hydrogen containing chlorofluorocarbons (HCFC 22 (CHClF2), HCFC 123 (CHCl2CF3), HCFC 124 (CHClFCF3), HCFC 141b (CFCl2CH3), HCFC 142b (CF2ClCH3)) and fluorocarbons (HFC 125 (CHF2CF3), HFC 134a (CH2FCF3), HFC 152a (CHF2CH3)) is assessed. Except for the initiation reaction by OH radicals, there are virtually no experimental data available concerning the subsequent oxidative breakdown of these molecules. However, from an analogy to the degradation mechanisms of simple alkanes, some useful guidelines as to the expected intermediates and final products can be derived. A noteable exception from this analogy, however, appears for the oxi-radicals. Here, halogen substitution induces new reaction types (C-Cl and C-C bond ruptures) which are unknown to the unsubstituted analogues and which modify the nature of the expected carbonyl products. Based on an evaluation of these processes using estimated bond strength data, the following simplified rules with regards to the chlorine content of the HCFC's may be deduced: (1) HCFC's containing one chlorine atom such as 22 and 142b seem to release their chlorine content essentially instantaneous with the initial attack on the parent by OH radicals, and for HCFC 124, such release is apparently prevented; (2) HCFC's such as 123 and 141b with two chlorine atoms are expected to release only one of these instantaneously; and the second chlorine atom may be stored in potentially long-lived carbonyl compounds such as CF3CClO or CClFO.

  15. First remote sensing observations of trifluoromethane (HFC-23) in the upper troposphere and lower stratosphere

    NASA Astrophysics Data System (ADS)

    Harrison, Jeremy J.; Boone, Christopher D.; Brown, Alexander T.; Allen, Nicholas D. C.; Toon, Geoffrey C.; Bernath, Peter F.

    2012-03-01

    This work reports the first remote sensing measurements of atmospheric HFC-23 (CHF3) using solar occultation measurements made by the Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS) and the Jet Propulsion Laboratory Mark IV (MkIV) balloon interferometer. A total of 8809 ACE occultations measured between 2004 and 2010 have been processed, along with 24 MkIV occultations measured between 1989 and 2007. ACE data (yearly averages over the 10-25 km altitude range) in the tropics/subtropics (40°S-40°N) reveal a trend of 4.0 ± 1.6% per year in the growth of HFC-23 for 2004-2009 (or 3.9 ± 1.2% per year for 2004-2010), slightly smaller than surface measurements from Cape Grim air archive samples over the same time period (4.7 ± 0.3% per year). The northern midlatitude and high-latitude MkIV data (averaged over the 10-25 km altitude range) indicate a growth rate of 5.8 ± 0.3% per year over the period 1989-2007 (5.3 ± 0.4% per year for just the midlatitude data), similar to the Cape Grim surface trend of 5.7 ± 0.1% per year over the same period. The absolute HFC-23 volume mixing ratios measured by ACE and MkIV in the upper troposphere/lower stratosphere are in good agreement (<5% bias) with each other but are ˜30% larger than ground-based measurements. The source of this bias has not been definitively ascertained; however, spectroscopic errors are the most likely cause.

  16. 10 CFR 431.62 - Definitions concerning commercial refrigerators, freezers and refrigerator-freezers.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...refrigerator, freezer, and refrigerator-freezer means refrigeration equipment that— (1) Is not a consumer product (as defined...Holding temperature application means a use of commercial refrigeration equipment other than a pull-down temperature...

  17. 10 CFR 431.62 - Definitions concerning commercial refrigerators, freezers and refrigerator-freezers.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...refrigerator, freezer, and refrigerator-freezer means refrigeration equipment that— (1) Is not a consumer product (as defined...Holding temperature application means a use of commercial refrigeration equipment other than a pull-down temperature...

  18. 10 CFR 431.62 - Definitions concerning commercial refrigerators, freezers and refrigerator-freezers.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...refrigerator, freezer, and refrigerator-freezer means refrigeration equipment that— (1) Is not a consumer product (as defined...Holding temperature application means a use of commercial refrigeration equipment other than a pull-down temperature...

  19. Discussion of Refrigeration Cycle Using Carbon Dioxide as Refrigerant

    NASA Astrophysics Data System (ADS)

    Ji, Amin; Sun, Miming; Li, Jie; Yin, Gang; Cheng, Keyong; Zhen, Bing; Sun, Ying

    Nowadays, the problem of the environment goes worse, it urges people to research and study new energy-saving and environment-friendly refrigerants, such as carbon dioxide, at present, people do research on carbon dioxide at home and abroad. This paper introduces the property of carbon dioxide as a refrigerant, sums up and analyses carbon dioxide refrigeration cycles, and points out the development and research direction in the future.

  20. Oxygen chemisorption cryogenic refrigerator

    NASA Technical Reports Server (NTRS)

    Jones, Jack A. (inventor)

    1987-01-01

    The present invention relates to a chemisorption compressor cryogenic refrigerator which employs oxygen to provide cooling at 60 to 100 K. The invention includes dual vessels containing an oxygen absorbent material, alternately heated and cooled to provide a continuous flow of high pressure oxygen, multiple heat exchangers for precooling the oxygen, a Joule-Thomson expansion valve system for expanding the oxygen to partially liquefy it and a liquid oxygen pressure vessel. The primary novelty is that, while it was believed that once oxygen combined with an element or compound the reaction could not reverse to release gaseous oxygen, in this case oxygen will indeed react in a reversible fashion with certain materials and will do so at temperatures and pressures which make it practical for incorporation into a cryogenic refrigeration system.

  1. Superfluid thermodynamic cycle refrigerator

    DOEpatents

    Swift, Gregory W. (Santa Fe, NM); Kotsubo, Vincent Y. (La Canada, CA)

    1992-01-01

    A cryogenic refrigerator cools a heat source by cyclically concentrating and diluting the amount of .sup.3 He in a single phase .sup.3 He-.sup.4 He solution. The .sup.3 He in superfluid .sup.4 He acts in a manner of an ideal gas in a vacuum. Thus, refrigeration is obtained using any conventional thermal cycle, but preferably a Stirling or Carnot cycle. A single phase solution of liquid .sup.3 He at an initial concentration in superfluid .sup.4 He is contained in a first variable volume connected to a second variable volume through a superleak device that enables free passage of .sup.4 He while restricting passage of .sup.3 He. The .sup.3 He is compressed (concentrated) and expanded (diluted) in a phased manner to carry out the selected thermal cycle to remove heat from the heat load for cooling below 1 K.

  2. Compact acoustic refrigerator

    SciTech Connect

    Bennett, G.A.

    1991-12-31

    This invention is comprised of a compact acoustic refrigeration system that actively cools components, e.g., electrical circuits, in a borehole environment. An acoustic engine includes first thermodynamic elements for generating a standing acoustic wave in a selected medium. An acoustic refrigerator includes second thermodynamic elements located in the standing wave for generating a relatively cold temperature at a first end of the second thermodynamic elements and a relatively hot temperature at a second end of the second thermodynamic elements. A resonator volume cooperates with the first and second thermodynamic elements to support the standing wave. To accommodate the high heat fluxes required for heat transfer to/from the first and second thermodynamic elements, first heat pipes transfer heat from the heat load to the second thermodynamic elements and second heat pipes transfer heat from first and second thermodynamic elements to the borehole environment.

  3. Compact acoustic refrigerator

    DOEpatents

    Bennett, G.A.

    1992-11-24

    A compact acoustic refrigeration system actively cools components, e.g., electrical circuits, in a borehole environment. An acoustic engine includes first thermodynamic elements for generating a standing acoustic wave in a selected medium. An acoustic refrigerator includes second thermodynamic elements located in the standing wave for generating a relatively cold temperature at a first end of the second thermodynamic elements and a relatively hot temperature at a second end of the second thermodynamic elements. A resonator volume cooperates with the first and second thermodynamic elements to support the standing wave. To accommodate the high heat fluxes required for heat transfer to/from the first and second thermodynamic elements, first heat pipes transfer heat from the heat load to the second thermodynamic elements and second heat pipes transfer heat from first and second thermodynamic elements to the borehole environment. 18 figs.

  4. Superfluid thermodynamic cycle refrigerator

    DOEpatents

    Swift, G.W.; Kotsubo, V.Y.

    1992-12-22

    A cryogenic refrigerator cools a heat source by cyclically concentrating and diluting the amount of [sup 3]He in a single phase [sup 3]He-[sup 4]He solution. The [sup 3]He in superfluid [sup 4]He acts in a manner of an ideal gas in a vacuum. Thus, refrigeration is obtained using any conventional thermal cycle, but preferably a Stirling or Carnot cycle. A single phase solution of liquid [sup 3]He at an initial concentration in superfluid [sup 4]He is contained in a first variable volume connected to a second variable volume through a superleak device that enables free passage of [sup 4]He while restricting passage of [sup 3]He. The [sup 3]He is compressed (concentrated) and expanded (diluted) in a phased manner to carry out the selected thermal cycle to remove heat from the heat load for cooling below 1 K. 12 figs.

  5. Compact acoustic refrigerator

    DOEpatents

    Bennett, Gloria A. (Los Alamos, NM)

    1992-01-01

    A compact acoustic refrigeration system actively cools components, e.g., electrical circuits (22), in a borehole environment. An acoustic engine (12, 14) includes first thermodynamic elements (12) for generating a standing acoustic wave in a selected medium. An acoustic refrigerator (16, 26, 28) includes second thermodynamic elements (16) located in the standing wave for generating a relatively cold temperature at a first end of the second thermodynamic elements (16) and a relatively hot temperature at a second end of the second thermodynamic elements (16). A resonator volume (18) cooperates with the first and second thermodynamic elements (12, 16) to support the standing wave. To accommodate the high heat fluxes required for heat transfer to/from the first and second thermodynamic elements (12, 16), first heat pipes (24, 26) transfer heat from the heat load (22) to the second thermodynamic elements (16) and second heat pipes (28, 32) transfer heat from first and second thermodynamic elements (12, 16) to the borehole environment.

  6. Reciprocating Magnetic Refrigerator

    NASA Technical Reports Server (NTRS)

    Johnson, D. L.

    1985-01-01

    Unit cools to 4 K by adiabatic demagnetization. Two porous matrices of paramagnetic material gadolinium/gallium/garnet held in long piston called displacer, machined out of Micarta (phenol formaldehyde polymer). Holes in side of displacer allow heat-exchange fluid to flow to and through matrices within. Piston seals on displacer prevent substantial mixing of fluid in two loops. Magnetic refrigerator provides continuous rather than "one-shot" cooling.

  7. Multilayer Thermionic Refrigeration

    SciTech Connect

    Mahan, G.D.

    1999-08-30

    A review is presented of our program to construct an efficient solid state refrigerator based on thermionic emission of electrons over periodic barriers in the solid. The experimental program is to construct a simple device with one barrier layer using a three layers: metal-semiconductor-metal. The theoretical program is doing calculations to determine: (i) the optimal layer thickness, and (ii) the thermal conductivity.

  8. Thermoacoustic Refrigerator's Stack Optimization

    NASA Astrophysics Data System (ADS)

    El-Fawal, Mawahib Hassan; Mohd-Ghazali, Normah; Yaacob, Mohd. Shafik; Darus, Amer Nordin

    2010-06-01

    The standing wave thermoacoustic refrigerator, which uses sound generation to transfer heat, was developed rapidly during the past four decades. It was regarded as a new, promising and environmentally benign alternative to conventional compression vapor refrigerators, although it was not competitive regarding the coefficient of performance (COP) yet. Thus the aim of this paper is to enhance thermoacoustic refrigerator's stack performance through optimization. A computational optimization procedure of thermoacoustic stack design was fully developed. The procedure was designed to achieve optimal coefficient of performance based on most of the design and operating parameters. Cooling load and acoustic power governing equations were set assuming the linear thermoacoustic theory. Lagrange multipliers method was used as an optimization technique tool to solve the governing equations. Numerical analyses results of the developed design procedure are presented. The results showed that the stack design parameters are the most significant parameters for the optimal overall performance. The coefficient of performance obtained increases by about 48.8% from the published experimental optimization methods. The results are in good agreement with past established studies.

  9. Vaccine refrigerator testing. Final report

    SciTech Connect

    Ventre, G.G.; Kilfoyle, D.; Marion, B.

    1990-06-01

    For the Central American Health Clinic Project initiated in 1986, Sandia National Laboratories and the Florida Solar Energy Center recognized the need for a test and evaluation program for vaccine refrigeration systems. At the Florida Solar Energy Center, side-by-side testing of three photovoltaic powered vaccine refrigerators began in 1987. The testing was expanded in 1988 to include a kerosene absorption refrigerator. This report presents observations, conclusions, and recommendations derived from testing the four vaccine refrigeration systems. Information is presented pertaining to the refrigerators, photovoltaic arrays, battery subsystems, charge controllers, and user requirements. This report should be of interest to designers, manufacturers, installers, and users of photovoltaic-powered vaccine refrigeration systems and components.

  10. Numerical simulation of oscillatory flow in an idealized thermoacoustic refrigerator

    NASA Astrophysics Data System (ADS)

    Besnoin, Etienne; Knio, Omar

    1998-11-01

    A vorticity-based computational model of an idealized thermoacoustic refrigerator is developed. The refrigerator consists of a stack of rectangular parallel plates and of heat exchangers on both sides of the stack. The heat exchangers are assumed to have a geometry similar to that of the stack and are separated from it by gaps whose widths can be varied. The evolution of the flow within the idealized refrigerator is described in terms of a low-Mach-number formulation of the compressible mass, momentum and energy conservation equations for an ideal gas mixture. The governing equations are simulated using a finite-difference solver which combines a domain-decomposition/boundary Green's function technique with fast Poisson solvers. The scheme is used to compute the response of the device to low-amplitude acoustic oscillations, and to analyze the evolution of the vorticity and temperature fields in the neighborhood of the stack and heat exchangers. * Supported by the Office of Naval Research

  11. NICE3: Industrial Refrigeration System

    SciTech Connect

    Simon, P.

    1999-09-29

    Energy Concepts has developed an absorption-augmented system as a cost-effective means of achieving more cooling capacity with a substantial reduction in energy consumption and greenhouse gas emissions for industrial refrigeration. It cuts fuel consumption by 30% by combining an internal combustion engine with a mechanical compression refrigeration system and an absorption refrigeration system. The absorption system is powered by engine waste heat. Conventional industrial refrigeration uses mechanical vapor compression, powered by electric motors, which results in higher energy costs. By the year 2010, the new system could cut fuel consumption by 19 trillion Btu and greenhouse emissions by more than 1 million tons per year.

  12. 49 CFR 173.174 - Refrigerating machines.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Refrigerating machines. 173.174 Section 173.174 Transportation...Class 1 and Class 7 § 173.174 Refrigerating machines. A refrigerating machine assembled for shipment and containing 7 kg...

  13. 49 CFR 173.174 - Refrigerating machines.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Refrigerating machines. 173.174 Section 173.174 Transportation...Class 1 and Class 7 § 173.174 Refrigerating machines. A refrigerating machine assembled for shipment and containing 7 kg...

  14. 49 CFR 173.174 - Refrigerating machines.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Refrigerating machines. 173.174 Section 173.174 Transportation...Class 1 and Class 7 § 173.174 Refrigerating machines. A refrigerating machine assembled for shipment and containing 7 kg...

  15. 49 CFR 173.174 - Refrigerating machines.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Refrigerating machines. 173.174 Section 173.174 Transportation...Class 1 and Class 7 § 173.174 Refrigerating machines. A refrigerating machine assembled for shipment and containing 7 kg...

  16. 49 CFR 173.174 - Refrigerating machines.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Refrigerating machines. 173.174 Section 173.174 Transportation...Class 1 and Class 7 § 173.174 Refrigerating machines. A refrigerating machine assembled for shipment and containing 7 kg...

  17. Performances of the mixed-gases Joule-Thomson refrigeration cycles for cooling fixed-temperature heat loads

    NASA Astrophysics Data System (ADS)

    Gong, M. Q.; Wu, J. F.; Luo, E. G.

    2004-12-01

    Numerous mixed-gases refrigeration cycle configurations based on Joule-Thomson effects were developed in the past several decades. In this paper, comprehensive thermodynamic analyses were made on two typical cycle configurations to learn their performance for cooling fixed-temperature heat loads. One is the single-stage cycle without phase separators; the other is the auto-cascade refrigeration cycle which has at least one phase separator. An exergy model was developed to analyze the thermodynamic performance of those refrigeration cycles. Comprehensive comparisons were made on the performance of the recuperative throttling cycles using multicomponent mixture as refrigerant, including extensive simulations and optimizations of mixtures and cycle configurations. The results show that the auto-cascade cycle can improve thermodynamic performance in the case of using mixtures with increased fraction of high-boiling components, however, degrade the performance when using mixtures with increased fraction of low-boiling components. The results also show that the mixed refrigerant is the most important designing parameter in the design of such mixed-gases refrigeration system. Different cycle configuration has different optimal mixture composition. When using optimal mixtures, both cycles (separation and non-separation) can provide approximately equal performance.

  18. Mechanism of the Enzymatic Synthesis of 4-(Hydroxymethyl)-2- furancarboxaldehyde-phosphate (4-HFC-P) from Glyceraldehyde-3-phosphate Catalyzed by 4-HFC-P Synthase.

    PubMed

    Wang, Yu; Jones, Michael K; Xu, Huimin; Ray, W Keith; White, Robert H

    2015-05-19

    A single enzyme, 4-(hydroxymethyl)-2-furancarboxaldehyde-phosphate synthase (MfnB), from the methanogen Methanocaldococcus jannaschii catalyzed at least 10 separate chemical reactions in converting two molecules of glyceraldehyde-3-P (GA-3-P) to 4-(hydroxymethyl)-2-furancarboxaldehyde-P (4-HFC-P), the first discrete intermediate in the biosynthetic pathway to the furan moiety of the coenzyme methanofuran. Here we describe the biochemical characterization of the recombinantly expressed MfnB to understand its catalytic mechanism. Site-directed mutagenesis showed that the strictly conserved residues (Asp25, Lys27, Lys85, and Asp151) around the active site are all essential for enzyme catalysis. Matrix-assisted laser desorption/ionization analysis of peptide fragments of MfnB incubated with GA-3-P followed by NaBH? reduction and trypsin digestion identified a peptide with a mass/charge ratio of 1668.8 m/z present only in the D25N, D151N, and K155R mutants, which is consistent with Lys27 having increased by a mass of 58 m/z, indicating that Lys27 forms a Schiff base with a methylglyoxal-like intermediate. In addition, incubation of MfnB with GA-3-P in the presence of deuterated water or incubation of MfnB with C-2 deuterated GA-3-P showed essentially no deuterium incorporated into the 4-HFC-P. Combined with structural analysis and molecular docking, we predict the potential binding sites for two GA-3P molecules in the active site. On the basis of our observations, a possible catalytic mechanism of MfnB is proposed in this study. A phosphate elimination reaction and a triose phosphate isomerase-like reaction occur at the GA-3-P binding site I and II, respectively, prior to the aldol condensation between the enzyme-bound enol form of methylglyoxal and dihydroxyacetone phosphate (DHAP), after which the catalytic cycle is completed by a cyclization and two dehydration reactions assisted by several general acids/bases at the same active site. PMID:25905665

  19. PERFORMANCE TESTING OF A SEMI-HERMETIC COMPRESSOR WITH HFC-236EA AND CFC-114 AT CHILLER CONDITIONS

    EPA Science Inventory

    The paper gives results of tests of both HFC-236ea and CFC-114 at a range of temperatures covering surface craft and submarine chiller conditions. vaporating temperatures ranged from 1.7 to 12.8 C, and condensing temperatures from 40.6 to 65.6 C, in order to develop a nine-point ...

  20. Complete Genome Sequence of Potential Probiotic Lactobacillus sp. HFC8, Isolated from Human Gut Using PacBio SMRT Sequencing

    PubMed Central

    Kumari, Madhu; Swarnkar, Mohit Kumar; Kumar, Sanjay

    2015-01-01

    We report a 3.07-Mb complete genome sequence of a lactic acid bacterium, Lactobacillus sp. HFC8. The gene-coding clusters are predicated for probiotic characteristics, like bacteriocin production, cell adhesion, bile salt hydrolysis, lactose metabolism, autoaggregation, and tolerance to oxidative stress. PMID:26586884

  1. Regenerative Sorption Refrigerator

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.; Wen, Liang-Chi; Bard, Steven

    1991-01-01

    Two-stage sorption refrigerator achieves increased efficiency via regenerative-heating concept in which waste heat from praseodymium/cerium oxide (PCO) chemisorption compressor runs charcoal/krypton (C/Kr) sorption compressor. Waste heat from each PCO sorption compressor used to power surrounding C/Kr sorption compressor. Flows of heat in two compressor modules controlled by gas-gap thermal switches. Has no wearing moving parts other than extremely long life, room-temperature check valves operating about twice per hour. Virtually no measurable vibration, and has potential operating life of at least ten years.

  2. Cycling Joule Thomson refrigerator

    NASA Technical Reports Server (NTRS)

    Tward, E. (inventor)

    1983-01-01

    A symmetrical adsorption pump/compressor system having a pair of mirror image legs and a Joule Thomson expander, or valve, interposed between the legs thereof for providing a, efficient refrigeration cycle is described. The system further includes a plurality of gas operational heat switches adapted selectively to transfer heat from a thermal load and to transfer or discharge heat through a heat projector, such as a radiator or the like. The heat switches comprise heat pressurizable chambers adapted for alternate pressurization in response to adsorption and desorption of a pressurizing gas confined therein.

  3. Semiconductor-based optical refrigerator

    DOEpatents

    Epstein, Richard I. (Santa Fe, NM); Edwards, Bradley C. (Nekoosa, WI); Sheik-Bahae, Mansoor (Albuquerque, NM)

    2002-01-01

    Optical refrigerators using semiconductor material as a cooling medium, with layers of material in close proximity to the cooling medium that carries away heat from the cooling material and preventing radiation trapping. In addition to the use of semiconducting material, the invention can be used with ytterbium-doped glass optical refrigerators.

  4. Helium dilution refrigeration system

    DOEpatents

    Roach, P.R.; Gray, K.E.

    1988-09-13

    A helium dilution refrigeration system operable over a limited time period, and recyclable for a next period of operation is disclosed. The refrigeration system is compact with a self-contained pumping system and heaters for operation of the system. A mixing chamber contains [sup 3]He and [sup 4]He liquids which are precooled by a coupled container containing [sup 3]He liquid, enabling the phase separation of a [sup 3]He rich liquid phase from a dilute [sup 3]He-[sup 4]He liquid phase which leads to the final stage of a dilution cooling process for obtaining low temperatures. The mixing chamber and a still are coupled by a fluid line and are maintained at substantially the same level with the still cross sectional area being smaller than that of the mixing chamber. This configuration provides maximum cooling power and efficiency by the cooling period ending when the [sup 3]He liquid is depleted from the mixing chamber with the mixing chamber nearly empty of liquid helium, thus avoiding unnecessary and inefficient cooling of a large amount of the dilute [sup 3]He-[sup 4]He liquid phase. 2 figs.

  5. Helium dilution refrigeration system

    DOEpatents

    Roach, Patrick R. (Darien, IL); Gray, Kenneth E. (Naperville, IL)

    1988-01-01

    A helium dilution refrigeration system operable over a limited time period, and recyclable for a next period of operation. The refrigeration system is compact with a self-contained pumping system and heaters for operation of the system. A mixing chamber contains .sup.3 He and .sup.4 He liquids which are precooled by a coupled container containing .sup.3 He liquid, enabling the phase separation of a .sup.3 He rich liquid phase from a dilute .sup.3 He-.sup.4 He liquid phase which leads to the final stage of a dilution cooling process for obtaining low temperatures. The mixing chamber and a still are coupled by a fluid line and are maintained at substantially the same level with the still cross sectional area being smaller than that of the mixing chamber. This configuration provides maximum cooling power and efficiency by the cooling period ending when the .sup.3 He liquid is depleted from the mixing chamber with the mixing chamber nearly empty of liquid helium, thus avoiding unnecessary and inefficient cooling of a large amount of the dilute .sup.3 He-.sup.4 He liquid phase.

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

    SciTech Connect

    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)

  7. M. Bahrami ENSC 461 (S 11) Refrigeration Cycle 1 Refrigeration Cycle

    E-print Network

    Bahrami, Majid

    M. Bahrami ENSC 461 (S 11) Refrigeration Cycle 1 Refrigeration Cycle Heat flows in direction of heat and work interactions. A refrigerator or heat pump that operates on the reversed Carnot cycle refrigerator. The reversed Carnot cycle is the most efficient refrigeration cycle operating between two

  8. 46 CFR 154.1720 - Indirect refrigeration.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Indirect refrigeration. 154.1720 Section 154.1720... § 154.1720 Indirect refrigeration. A refrigeration system that is used to cool acetaldehyde, ethylene oxide, or methyl bromide, must be an indirect refrigeration system that does not use vapor compression....

  9. Mixture Experiments

    SciTech Connect

    Piepel, Gregory F.

    2007-12-01

    A mixture experiment involves combining two or more components in various proportions or amounts and then measuring one or more responses for the resulting end products. Other factors that affect the response(s), such as process variables and/or the total amount of the mixture, may also be studied in the experiment. A mixture experiment design specifies the combinations of mixture components and other experimental factors (if any) to be studied and the response variable(s) to be measured. Mixture experiment data analyses are then used to achieve the desired goals, which may include (i) understanding the effects of components and other factors on the response(s), (ii) identifying components and other factors with significant and nonsignificant effects on the response(s), (iii) developing models for predicting the response(s) as functions of the mixture components and any other factors, and (iv) developing end-products with desired values and uncertainties of the response(s). Given a mixture experiment problem, a practitioner must consider the possible approaches for designing the experiment and analyzing the data, and then select the approach best suited to the problem. Eight possible approaches include 1) component proportions, 2) mathematically independent variables, 3) slack variable, 4) mixture amount, 5) component amounts, 6) mixture process variable, 7) mixture of mixtures, and 8) multi-factor mixture. The article provides an overview of the mixture experiment designs, models, and data analyses for these approaches.

  10. saturated liquid. The region above the vapor line is superheated vapor; that below the lower line is subcooled liquid. The region enclosed by the pair represents a mixture of liquid and

    E-print Network

    Oak Ridge National Laboratory

    line is subcooled liquid. The region enclosed by the pair represents a mixture of liquid and vapor are as follows: Assume the system is charged with a mixture having a concentration of component A designated, the refrigerant will be a mixture of liquid and vapor, as usually occurs in a single-refrigerant system. One

  11. Using Acid Number as a Leading Indicator of Refrigeration and Air Conditioning System Performance

    SciTech Connect

    Dennis Cartlidge; Hans Schellhase

    2003-07-31

    This report summarizes a literature review to assess the acidity characteristics of the older mineral oil and newer polyolester (POE) refrigeration systems as well as to evaluate acid measuring techniques used in other non-aqueous systems which may be applicable for refrigeration systems. Failure in the older chlorofluorocarbon/hydrochlorofluorocarbon (CFC/HCFC) / mineral oil systems was primarily due to thermal degradation of the refrigerant which resulted in the formation of hydrochloric and hydrofluoric acids. These are strong mineral acids, which can, over time, severely corrode the system metals and lead to the formation of copper plating on iron surfaces. The oil lubricants used in the older systems were relatively stable and were not prone to hydrolytic degradation due to the low solubility of water in oil. The refrigerants in the newer hydrofluorocarbon (HFC)/POE systems are much more thermally stable than the older CFC/HCFC refrigerants and mineral acid formation is negligible. However, acidity is produced in the new systems by hydrolytic decomposition of the POE lubricants with water to produce the parent organic acids and alcohols used to prepare the POE. The individual acids can therefore vary but they are generally C5 to C9 carboxylic acids. Organic acids are much weaker and far less corrosive to metals than the mineral acids from the older systems but they can, over long time periods, react with metals to form carboxylic metal salts. The salts tend to accumulate in narrow areas such as capillary tubes, particularly if residual hydrocarbon processing chemicals are present in the system, which can lead to plugging. The rate of acid production from POEs varies on a number of factors including chemical structure, moisture levels, temperature, acid concentration and metals. The hydrolysis rate of reaction can be reduced by using driers to reduce the free water concentration and by using scavenging chemicals which react with the system acids. Total acid number (TAN), which includes both mineral acids and organic acids, is therefore a useful indicator which can be used to monitor the condition of the system in order to perform remedial maintenance, when required, to prevent system failure. The critical TAN value is the acid level at which remedial action should be taken to prevent the onset of rapid acid formation which can result in system failure. The level of 0.05 mg KOH/g of oil was established for CFC/mineral oil systems based on analysis of 700 used lubricants from operating systems and failed units. There is no consensus within the refrigeration industry as to the critical TAN value for HFC/POE systems, however, the value will be higher than the CFC/mineral oil systems critical TAN value because of the much weaker organic acids produced from POE. A similar study of used POE lubricants should be performed to establish a critical TAN limit for POE systems. Titrimetric analysis per ASTM procedures is the most commonly used method to determine TAN values in lubricants in the refrigeration industry and other industries dealing with lubricating oils. For field measurements, acid test kits are often used since they provide rapid, semi-quantitative TAN results.

  12. Magnetic refrigeration for maser amplifier cooling

    NASA Technical Reports Server (NTRS)

    Johnson, D. L.

    1982-01-01

    The development of a multifrequency upconverter-maser system for the DSN has created the need to develop a closed-cycle refrigerator (CCR) capable of providing more than 3 watts of refrigeration capability at 4.5 K. In addition, operating concerns such as the high cost of electrical power consumption and the loss of maser operation due to CCR failures require that improvements be made to increase the efficiency and reliability of the CCR. One refrigeration method considered is the replacement of the Joule-Thomson expansion circuit with a magnetic refrigeration. Magnetic refrigerators can provide potentially reliable and highly efficient refrigeration at a variety of temperature ranges and cooling power. The concept of magnetic refrigeration is summarized and a literature review of existing magnetic refrigerator designs which have been built and tested and that may also be considered as possibilities as a 4 K to 15 K magnetic refrigeration stage for the DSN closed-cycle refrigerator is provided.

  13. Cryogenic refrigeration apparatus

    DOEpatents

    Crunkleton, James A. (Cambridge, MA)

    1992-01-01

    A technique for producing a cold environment in a refrigerant system in which input fluid from a compressor at a first temperature is introduced into an input channel of the system and is pre-cooled to a second temperature for supply to one of at least two stages of the system, and to a third temperature for supply to another stage thereof. The temperatures at such stages are reduced to fourth and fifth temperatures below the second and third temperatures, respectively. Fluid at the fourth temperature from the one stage is returned through the input channel to the compressor and fluid at the fifth temperature from the other stage is returned to the compressor through an output channel so that pre-cooling of the input fluid to the one stage occurs by regenerative cooling and counterflow cooling and pre-cooling of the input fluid to the other stage occurs primarily by counterflow cooling.

  14. Multistation refrigeration system

    NASA Technical Reports Server (NTRS)

    Wiebe, E. R. (inventor)

    1978-01-01

    A closed cycle refrigeration (CCR) system is disclosed for providing cooling at different parts of a maser. The CCR includes a first station for cooling the maser's parts, except the amplifier portion, to 4.5 K. The CCR further includes means with a 3.0 K station for cooling the maser's amplifier to 3.0 K and, thereby, increases the maser's gain and/or bandwith by a significant factor. The means which provide the 3.0 K cooling include a pressure regulator, heat exchangers, an expansion valve, and a vacuum pump, which coact to cause helium, provided from a compressor, to liquefy and thereafter expand so as to vaporize. The heat of vaporization for the helium is provided by the maser amplifier, which is thereby cooled to 3.0 K.

  15. Cryogenic refrigeration apparatus

    DOEpatents

    Crunkleton, J.A.

    1992-03-31

    A technique for producing a cold environment in a refrigerant system in which input fluid from a compressor at a first temperature is introduced into an input channel of the system and is pre-cooled to a second temperature for supply to one of at least two stages of the system, and to a third temperature for supply to another stage thereof. The temperatures at such stages are reduced to fourth and fifth temperatures below the second and third temperatures, respectively. Fluid at the fourth temperature from the one stage is returned through the input channel to the compressor and fluid at the fifth temperature from the other stage is returned to the compressor through an output channel so that pre-cooling of the input fluid to the one stage occurs by regenerative cooling and counterflow cooling and pre-cooling of the input fluid to the other stage occurs primarily by counterflow cooling. 6 figs.

  16. Control system for thermoelectric refrigerator

    NASA Technical Reports Server (NTRS)

    Nelson, John L. (Inventor); Criscuolo, Lance (Inventor); Gilley, Michael D. (Inventor); Park, Brian V. (Inventor)

    1996-01-01

    Apparatus including a power supply (202) and control system is provided for maintaining the temperature within an enclosed structure (40) using thermoelectric devices (92). The apparatus may be particularly beneficial for use with a refrigerator (20) having superinsulation materials (46) and phase change materials (112) which cooperate with the thermoelectric device (92) to substantially enhance the overall operating efficiency of the refrigerator (20). The electrical power supply (202) and control system allows increasing the maximum power capability of the thermoelectric device (92) in response to increased heat loads within the refrigerator (20). The electrical power supply (202) and control system may also be used to monitor the performance of the cooling system (70) associated with the refrigerator (20).

  17. Magnetic refrigeration apparatus and method

    DOEpatents

    Barclay, John A. (Los Alamos, NM); Overton, Jr., William C. (Los Alamos, NM); Stewart, Walter F. (Los Alamos, NM)

    1984-01-01

    The disclosure relates to refrigeration through magnetizing and demagnitizing a body by rotating it within a magnetic field. Internal and external heat exchange fluids and in one embodiment, a regenerator, are used.

  18. Short-Cycle Adsorption Refrigerator

    NASA Technical Reports Server (NTRS)

    Chan, C. K.

    1988-01-01

    Modular adsorption/Joule-Thomson-effect refrigerator offers fast regeneration; adsorption/desorption cycle time expected to be 1 minute. Pressurized hydrogen generated by bank of compressor modules during heating phase passes through system of check valves and expands in Joule-Thomson junction as it enters refrigeration chamber. Hydrogen absorbs heat from load before it is sucked out by another bank of compressor modules in cooling phase.

  19. Non-intrusive refrigerant charge indicator

    DOEpatents

    Mei, Viung C.; Chen, Fang C.; Kweller, Esher

    2005-03-22

    A non-intrusive refrigerant charge level indicator includes a structure for measuring at least one temperature at an outside surface of a two-phase refrigerant line section. The measured temperature can be used to determine the refrigerant charge status of an HVAC system, and can be converted to a pressure of the refrigerant in the line section and compared to a recommended pressure range to determine whether the system is under-charged, properly charged or over-charged. A non-intrusive method for assessing the refrigerant charge level in a system containing a refrigerant fluid includes the step of measuring a temperature at least one outside surface of a two-phase region of a refrigerant containing refrigerant line, wherein the temperature measured can be converted to a refrigerant pressure within the line section.

  20. Heat transfer characteristics of alternate refrigerants: Volume 2, Condenser inside tube. Final report

    SciTech Connect

    Dunn, B.

    1996-01-01

    An experimental facility was constructed to determine the condensing heat transfer coefficients of alternative refrigerants in horizontal, enhanced tubes. The experimental facility was designed to handle a wide range of operating conditions while demanding a minimal refrigerant charge. Gas chromatography was utilized to measure the composition of refrigerant mixtures and the oil concentration. Measurements were obtained for six R-22 replacements and four R-502 replacements along with baseline data for R-22 and R-502. Each refrigerant was tested at 0% and 1% oil by weight, four different mass flow rates (75, 150, 250, and 400 lb{sub m}/hr), and three different heat fluxes (corresponding to full condensation in 18.5, 37, and 55.5-ft.). All tests were performed in a 3/8 in. Wolverine Turbo A microgrooved tube. The data for R-22 compared well with published data and correlations. The measured heat transfer coefficients for most of the alternatives were very close to the heat transfer coefficient of the refrigerant they would be replacing. It was found that some of the zeotropic refrigerants performed poorly at low heat fluxes and low mass flow rates, as expected. 1% oil in the refrigerant flow had very little impact on heat transfer coefficients. Also, it was found that at the highest mass flow rates the data compare well with published data for smooth tubes, indicating that very little enhancement occurs in this regime.

  1. Shear viscosity of binary mixtures: The Gay-Berne potential

    NASA Astrophysics Data System (ADS)

    Khordad, R.

    2012-05-01

    The Gay-Berne (GB) potential model is an interesting and useful model to study the real systems. Using the potential model, we intend to examine the thermodynamical properties of some anisotropic binary mixtures in two different phases, liquid and gas. For this purpose, we apply the integral equation method and solve numerically the Percus-Yevick (PY) integral equation. Then, we obtain the expansion coefficients of correlation functions to calculate the thermodynamical properties. Finally, we compare our results with the available experimental data [e.g., HFC-125 + propane, R-125/143a, methanol + toluene, benzene + methanol, cyclohexane + ethanol, benzene + ethanol, carbon tetrachloride + ethyl acetate, and methanol + ethanol]. The results show that the GB potential model is capable for predicting the thermodynamical properties of binary mixtures with acceptable accuracy.

  2. 46 CFR 151.40-11 - Refrigeration systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Refrigeration systems. 151.40-11 Section...Control Installations § 151.40-11 Refrigeration systems. (a) Boiloff systems... (b) Vapor compression, tank refrigeration, and secondary refrigeration...

  3. 46 CFR 151.40-11 - Refrigeration systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Refrigeration systems. 151.40-11 Section...Control Installations § 151.40-11 Refrigeration systems. (a) Boiloff systems... (b) Vapor compression, tank refrigeration, and secondary refrigeration...

  4. 46 CFR 151.40-11 - Refrigeration systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Refrigeration systems. 151.40-11 Section...Control Installations § 151.40-11 Refrigeration systems. (a) Boiloff systems... (b) Vapor compression, tank refrigeration, and secondary refrigeration...

  5. 46 CFR 151.40-11 - Refrigeration systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Refrigeration systems. 151.40-11 Section...Control Installations § 151.40-11 Refrigeration systems. (a) Boiloff systems... (b) Vapor compression, tank refrigeration, and secondary refrigeration...

  6. 46 CFR 151.40-11 - Refrigeration systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Refrigeration systems. 151.40-11 Section...Control Installations § 151.40-11 Refrigeration systems. (a) Boiloff systems... (b) Vapor compression, tank refrigeration, and secondary refrigeration...

  7. A ``Dilution Refrigerator'' Using Spin-Polarized Fermions

    NASA Astrophysics Data System (ADS)

    Basu, Sourish; Mueller, Erich J.

    2009-05-01

    We present an analogy between a population imbalanced two component Fermi gas on the BEC side of a Feshbach resonance and a ^3He-^4He mixture. The bosonic pairs are analogous to ^4He and the fermionic unpaired atoms to ^3He. These systems have topologically indistinguishable phase diagrams: at low temperatures the system phase separates into a fermion rich and a fermion poor region. As in standard cryogenic setups, one can in principle create a refrigerator which cools based upon the fact that there is a latent heat associated with pulling particles from the fermion rich region into the fermion poor one. We explore this idea, calculating the entropy of mixing, and suggesting cold atom geometries which mimic the anatomy of a standard ^3He-^4He dilution refrigerator.

  8. Air conditioning and refrigeration engineering

    SciTech Connect

    Kreith, F.

    1999-12-01

    This book supplies the basics of design, from selecting the optimum system and equipment to preparing the drawings and specifications. It discusses the four phases of preparing a project: gathering information, developing alternatives, evaluating alternatives, and selling the best solution. In addition, the author breaks down the responsibilities of the engineer design documents, computer aided design, and government codes and standards. It provides you with an easy reference to all aspects of the topic. This resource addresses the most current areas of interest, such as computer aided design and drafting, desiccant air conditioning and energy conservation. It is a thorough and convenient guide to air conditioning and refrigeration engineering. Contents include: introduction; psychrometrics; air-conditioning processes and cycles; refrigerants and refrigeration cycles; outdoor design conditions and indoor design criteria; load calculations; air handling units and packaged units; refrigeration components and evaporative coolers; water systems; heating systems; refrigeration systems; thermal storage system; air system basics; absorption systems; air-conditioning systems and selection; and desiccant dehumidification and air-conditioning.

  9. Review of recent research on heat transfer with mixtures. Part 1: Condensation

    SciTech Connect

    Wang, S.P.; Chato, J.C.

    1995-08-01

    During the past 10 years, interest in heat transfer with mixtures has increased for several reasons. First, the use of zeotropic refrigerant mixtures (ZERMs) as working fluids in heat pump and refrigeration systems indicates potential advantages in efficiency and capacity. Second, ZERMs are prospective substitutes for chlorofluorocarbon (CFC) and hydrochlorofluorocarbon (HCFC) refrigerants (such as R12, R-11, and R-22). However, before the refrigerant mixtures will be put to use in heat pump, refrigerator, and air conditioning systems, the problem of possibly changed heat transfer performance and pressure drop in condensation processes has to be considered to realize the claimed advantages. Thus, it is necessary to study the mechanisms of condensation with mixtures. In this paper, a companion to one on boiling and evaporation, the recent research on condensation heat transfer with mixtures is reviewed. The main points are the thermal resistance of the vapor diffusion layer affecting the condensation, the influence of the flow direction of vapor on the condensation, the turbulence in the vapor generated by the fins, and the enhancement of the condensation performance of mixtures. This review is mainly concerned with the condensation of miscible mixtures, especially ZERMs. Only a few selected papers related to immiscible mixtures are reviewed here.

  10. 10 CFR 431.62 - Definitions concerning commercial refrigerators, freezers and refrigerator-freezers.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Definitions concerning commercial refrigerators, freezers and refrigerator-freezers. 431.62 Section 431.62 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Commercial Refrigerators, Freezers and Refrigerator-Freezers §...

  11. EVALUATION OF REFRIGERANT FROM MOBILE AIR CONDITIONERS

    EPA Science Inventory

    The report gives results of a project to provide a scientific basis for choosing a reasonable standard of purity for recycled chlorofluorocarbon (CFC) refrigerant in operating automobile air conditioners. The quality of refrigerant from air conditioners in automobiles of differen...

  12. Energy Saving with Absorption Refrigeration Technologies 

    E-print Network

    Davis, R. C.

    1984-01-01

    Absorption refrigeration technology can be an economical and cost effective means of reducing energy cost and/or improving the efficiency and output of your process. We believe the potential benefits of absorption refrigeration technology have...

  13. Krypton based adsorption type cryogenic refrigerator

    NASA Technical Reports Server (NTRS)

    Jones, Jack A. (inventor); Schember, Helene (inventor)

    1987-01-01

    Krypton and monolithic porous carbon such as Saran carbon are used respectively as the sorbate and sorbent of an absorption type refrigerator to improve refrigeration efficiency and operational longevity.

  14. Krypton based adsorption type cryogenic refrigerator

    NASA Technical Reports Server (NTRS)

    Jones, Jack A. (Inventor); Schember, Helene R. (Inventor)

    1989-01-01

    Krypton and a monolithic porous carbon such as Saran carbon are used respectively as the sorbate and sorbent of an adsorption type refrigerator to improve refrigeration efficiency and operational longevity.

  15. Thermoelectric refrigerator having improved temperature stabilization means

    DOEpatents

    Falco, Charles M. (Woodridge, IL)

    1982-01-01

    A control system for thermoelectric refrigerators is disclosed. The thermoelectric refrigerator includes at least one thermoelectric element that undergoes a first order change at a predetermined critical temperature. The element functions as a thermoelectric refrigerator element above the critical temperature, but discontinuously ceases to function as a thermoelectric refrigerator element below the critical temperature. One example of such an arrangement includes thermoelectric refrigerator elements which are superconductors. The transition temperature of one of the superconductor elements is selected as the temperature control point of the refrigerator. When the refrigerator attempts to cool below the point, the metals become superconductors losing their ability to perform as a thermoelectric refrigerator. An extremely accurate, first-order control is realized.

  16. REDUCING REFRIGERANT EMISSIONS FROM SUPERMARKET SYSTEMS

    EPA Science Inventory

    Large refrigeration systems are found in several applications including supermarkets, cold storage warehouses, and industrial processes. The sizes of these systems are a contributing factor to their problems of high refrigerant leak rates because of the thousands of connections, ...

  17. A review of pulse tube refrigeration

    NASA Technical Reports Server (NTRS)

    Radebaugh, Ray

    1990-01-01

    This paper reviews the development of the three types of pulse tube refrigerators: basic, resonant, and orifice types. The principles of operation are given. It is shown that the pulse tube refrigerator is a variation of the Stirling-cycle refrigerator, where the moving displacer is substituted by a heat transfer mechanism or by an orifice to bring about the proper phase shifts between pressure and mass flow rate. A harmonic analysis with phasors is described which gives reasonable results for the refrigeration power, yet is simple enough to make clear the processes which give rise to the refrigeration. The efficiency and refrigeration power are compared with those of other refrigeration cycles. A brief review is given of the research being done at various laboratories on both one- and two-stage pulse tubes. A preliminary assessment of the role of pulse tube refrigerators is discussed.

  18. A historical look at chlorofluorocarbon refrigerants

    SciTech Connect

    Bhatti, M.S.

    1999-07-01

    A class of chemical compounds called chlorofluorocarbon refrigerants has been in widespread use since the 1930s in such diverse applications as refrigerants for refrigerating and air-conditioning systems, blowing agents for plastic foams, solvents for microelectronic circuitry and dry cleaning, sterilants for medical instruments, aerosol propellants for personal hygiene products and pesticides, and freezants for food. This paper describes the historical development of the chlorofluorocarbon refrigerants and gives brief biographical sketches of the inventors. 85 refs., 8 figs., 4 tabs.

  19. Dynamic chiral-at-metal stability of tetrakis(d/l-hfc)Ln(III) complexes capped with an alkali metal cation in solution.

    PubMed

    Lin, Yiji; Zou, Fang; Wan, Shigang; Ouyang, Jie; Lin, Lirong; Zhang, Hui

    2012-06-14

    Chiral tetrakis(?-diketonate) Ln(III) complexes ?-[NaLa(d-hfc)(4)(CH(3)CN)] (1) and ?-[NaLa(l-hfc)(4) (CH(3)CN)] (2) (d/l-hfc(-) = 3-heptafluo-robutylryl-(+)/(-)-camphorate) are a pair of enantiomers and crystallize in the same Sohncke space group (P2(1)2(1)2(1)) with dodecahedral (DD) geometry. Typically positive and negative exciton splitting patterns around 320 nm were observed in the solid-state circular dichroism (CD) spectra of complexes 1 and 2, which indicate that their shell configurational chiralities are ? and ?, respectively. The apparent bisignate couplets in the solid-state CD spectra of [CsLn(d-hfc)(4)(H(2)O)] [Ln = La (3), Yb (5)] and [CsLn(l-hfc)(4)(H(2)O)] [Ln = La (4), Yb (6)] show that they are a pair of enantiomers and their absolute configurations are denoted ? and ?, respectively. The crystallographic data of 5 reveals that its coordination polyhedron is the square antiprism (SAP) geometry and it undergoes a phase transition from triclinic (? phase, P1) to monoclinic (? phase, C2) upon cooling. The difference between the two phases is brought about by the temperature dependent behaviour of the coordination water molecules, but this did not affect the configurational chirality of the ?-SAP-[Yb(d-hfc)(4)](-) moiety. Furthermore, time-dependent CD, UV-vis and (19)F NMR were applied to study the solution behavior of these complexes. It was found that the chiral-at-metal stability of the three pairs of complexes is different and affected by both the Ln(3+) and M(+) ion size. The results show that the Cs(+) cation can retain the metal center chirality and stablize the structures of [Ln(d/l-hfc)(4)](-) or the dissociated tris(d/l-hfc)Ln(III) species in solution for a longer time than that of the Na(+) cation, and it is important that the Cs(+) ion successfully lock the configurational chirality around the Yb(3+) center of the complex species in solution. This is reasoned by the short Cs(+)···FC, Cs(+)···O-Yb and Cs(+)···Yb(3+) interactions observed in the crystal structure of ?-5 and further confirmed by the chiral self-assembly of 5 or 6 from [Yb(H(2)O)(d/l-hfc)(3)] induced by CsI in a CHCl(3) solution. PMID:22538249

  20. Wheel-type magnetic refrigerator

    DOEpatents

    Barclay, John A. (Los Alamos, NM)

    1983-01-01

    The disclosure is directed to a wheel-type magnetic refrigerator capable of cooling over a large temperature range. Ferromagnetic or paramagnetic porous materials are layered circumferentially according to their Curie temperature. The innermost layer has the lowest Curie temperature and the outermost layer has the highest Curie temperature. The wheel is rotated through a magnetic field perpendicular to the axis of the wheel and parallel to its direction of rotation. A fluid is pumped through portions of the layers using inner and outer manifolds to achieve refrigeration of a thermal load.

  1. Wheel-type magnetic refrigerator

    DOEpatents

    Barclay, J.A.

    1982-01-20

    The disclosure is directed to a wheel-type magnetic refrigerator capable of cooling over a large temperature range. Ferromagnetic or paramagnetic porous materials are layered circumferentially according to their Curie temperature. The innermost layer has the lowest Curie temperature and the outermost layer has the highest Curie temperature. The wheel is rotated through a magnetic field perpendicular to the axis of the wheel and parallel to its direction of rotation. A fluid is pumped through portions of the layers using inner and outer manifolds to achieve refrigeration of a thermal load.

  2. Wheel-type magnetic refrigerator

    DOEpatents

    Barclay, J.A.

    1983-10-11

    The disclosure is directed to a wheel-type magnetic refrigerator capable of cooling over a large temperature range. Ferromagnetic or paramagnetic porous materials are layered circumferentially according to their Curie temperature. The innermost layer has the lowest Curie temperature and the outermost layer has the highest Curie temperature. The wheel is rotated through a magnetic field perpendicular to the axis of the wheel and parallel to its direction of rotation. A fluid is pumped through portions of the layers using inner and outer manifolds to achieve refrigeration of a thermal load. 7 figs.

  3. 46 CFR 147.90 - Refrigerants.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Refrigerants. 147.90 Section 147.90 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DANGEROUS CARGOES HAZARDOUS SHIPS' STORES Stowage and Other Special Requirements for Particular Materials § 147.90 Refrigerants. (a) Only refrigerants listed in ANSI/ASHRAE 34-78 may be carried as...

  4. 49 CFR 173.174 - Refrigerating machines.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Refrigerating machines. 173.174 Section 173.174 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... Refrigerating machines. A refrigerating machine assembled for shipment and containing 7 kg (15 pounds) or...

  5. 49 CFR 173.174 - Refrigerating machines.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Refrigerating machines. 173.174 Section 173.174 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... Refrigerating machines. A refrigerating machine assembled for shipment and containing 7 kg (15 pounds) or...

  6. 49 CFR 173.174 - Refrigerating machines.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Refrigerating machines. 173.174 Section 173.174 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... Refrigerating machines. A refrigerating machine assembled for shipment and containing 7 kg (15 pounds) or...

  7. 49 CFR 173.174 - Refrigerating machines.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Refrigerating machines. 173.174 Section 173.174 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... Refrigerating machines. A refrigerating machine assembled for shipment and containing 7 kg (15 pounds) or...

  8. 49 CFR 173.174 - Refrigerating machines.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Refrigerating machines. 173.174 Section 173.174 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... Refrigerating machines. A refrigerating machine assembled for shipment and containing 7 kg (15 pounds) or...

  9. Piston sealing arrangement for a cryogenic refrigerator

    SciTech Connect

    Green, G.F.; Humphrey, J.C.

    1984-02-21

    A sealing arrangement for a rectilinear reciprocable piston within a cryogenic refrigerator comprising a buffer defined by dual O-rings disposed around the circumference of the piston and containing pressurized gas of the same type as the refrigeration gas. The buffer limits or prevents both the entrance of contaminants and also the escape of the refrigeration gas.

  10. Solar Refrigerators Store Life-Saving Vaccines

    NASA Technical Reports Server (NTRS)

    2014-01-01

    Former Johnson Space Center engineer David Bergeron used his experience on the Advanced Refrigeration Technology Team to found SunDanzer Refrigeration Inc., a company specializing in solar-powered refrigerators. The company has created a battery-free unit that provides safe storage for vaccines in rural and remote areas around the world.

  11. Ternary Dy-Er-Al magnetic refrigerants

    DOEpatents

    Gschneidner, K.A. Jr.; Takeya, Hiroyuki

    1995-07-25

    A ternary magnetic refrigerant material comprising (Dy{sub 1{minus}x}Er{sub x})Al{sub 2} for a magnetic refrigerator using the Joule-Brayton thermodynamic cycle spanning a temperature range from about 60K to about 10K, which can be adjusted by changing the Dy to Er ratio of the refrigerant. 29 figs.

  12. Ternary Dy-Er-Al magnetic refrigerants

    DOEpatents

    Gschneidner, Jr., Karl A. (Ames, IA); Takeya, Hiroyuki (Ibaraki, JP)

    1995-07-25

    A ternary magnetic refrigerant material comprising (Dy.sub.1-x Er.sub.x)Al.sub.2 for a magnetic refrigerator using the Joule-Brayton thermodynamic cycle spanning a temperature range from about 60K to about 10K, which can be adjusted by changing the Dy to Er ratio of the refrigerant.

  13. Method and apparatus for desuperheating refrigerant

    DOEpatents

    Zess, James A. (Kelso, WA); Drost, M. Kevin (Richland, WA); Call, Charles J. (Richland, WA)

    1997-01-01

    The present invention is an apparatus and method for de-superheating a primary refrigerant leaving a compressor wherein a secondary refrigerant is used between the primary refrigerant to be de-superheated. Reject heat is advantageously used for heat reclaim.

  14. 21 CFR 1250.34 - Refrigeration equipment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...and Drugs 8 2011-04-01 2011-04-01 false Refrigeration equipment. 1250.34 Section 1250.34 Food and Drugs...on Land and Air Conveyances, and Vessels § 1250.34 Refrigeration equipment. Each refrigerator shall be equipped with...

  15. 21 CFR 1250.34 - Refrigeration equipment.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...and Drugs 8 2013-04-01 2013-04-01 false Refrigeration equipment. 1250.34 Section 1250.34 Food and Drugs...on Land and Air Conveyances, and Vessels § 1250.34 Refrigeration equipment. Each refrigerator shall be equipped with...

  16. Magnetic refrigeration using flux compression in superconductors

    NASA Technical Reports Server (NTRS)

    Israelsson, U. E.; Strayer, D. M.; Jackson, H. W.; Petrac, D.

    1990-01-01

    The feasibility of using flux compression in high-temperature superconductors to produce the large time-varying magnetic fields required in a field cycled magnetic refrigerator operating between 20 K and 4 K is presently investigated. This paper describes the refrigerator concept and lists limitations and advantages in comparison with conventional refrigeration techniques. The maximum fields obtainable by flux compression in high-temperature supercoductor materials, as presently prepared, are too low to serve in such a refrigerator. However, reports exist of critical current values that are near usable levels for flux pumps in refrigerator applications.

  17. Energy Efficient, Environmentally Friendly Refrigerants 

    E-print Network

    Nimitz, J.; Glass, S.; Dhooge, P. M.

    1998-01-01

    , low global warming potential, relatively low toxicity, is compatible with most common refrigeration system materials of construction, and is thermally stable. Ikon B was used as a drop-in replacement for R-12 in an instrumented 1.5 ton chiller...

  18. Low-temperature magnetic refrigerator

    DOEpatents

    Barclay, John A. (Los Alamos, NM)

    1985-01-01

    The disclosure is directed to a low temperature 4 to 20 K. refrigeration apparatus and method utilizing a ring of magnetic material moving through a magnetic field. Heat exchange is accomplished in and out of the magnetic field to appropriately utilize the device to execute Carnot and Stirling cycles.

  19. Solar-Powered Refrigeration System

    NASA Technical Reports Server (NTRS)

    Ewert, Michael K. (Inventor); Bergeron, David J., III (Inventor)

    2002-01-01

    A solar powered vapor compression refrigeration system is made practicable with thermal storage and novel control techniques. In one embodiment, the refrigeration system includes a photovoltaic panel, a variable speed compressor, an insulated enclosure, and a thermal reservoir. The photovoltaic (PV) panel converts sunlight into DC (direct current) electrical power. The DC electrical power drives a compressor that circulates refrigerant through a vapor compression refrigeration loop to extract heat from the insulated enclosure. The thermal reservoir is situated inside the insulated enclosure and includes a phase change material. As heat is extracted from the insulated enclosure, the phase change material is frozen, and thereafter is able to act as a heat sink to maintain the temperature of the insulated enclosure in the absence of sunlight. The conversion of solar power into stored thermal energy is optimized by a compressor control method that effectively maximizes the compressor's usage of available energy. A capacitor is provided to smooth the power voltage and to provide additional current during compressor start-up. A controller monitors the rate of change of the smoothed power voltage to determine if the compressor is operating below or above the available power maximum, and adjusts the compressor speed accordingly. In this manner, the compressor operation is adjusted to convert substantially all available solar power into stored thermal energy.

  20. Solar-Powered Refrigeration System

    NASA Technical Reports Server (NTRS)

    Ewert, Michael K. (Inventor); Bergeron, David J., III (Inventor)

    2001-01-01

    A solar powered vapor compression refrigeration system is made practicable with thermal storage and novel control techniques. In one embodiment, the refrigeration system includes a photovoltaic panel, a variable speed compressor, an insulated enclosure. and a thermal reservoir. The photovoltaic (PV) panel converts sunlight into DC (direct current) electrical power. The DC electrical power drives a compressor that circulates refrigerant through a vapor compression refrigeration loop to extract heat from the insulated enclosure. The thermal reservoir is situated inside the insulated enclosure and includes a phase change material. As heat is extracted from the insulated enclosure, the phase change material is frozen, and thereafter is able to act as a heat sink to maintain the temperature of the insulated enclosure in the absence of sunlight. The conversion of solar power into stored thermal energy is optimized by a compressor control method that effectively maximizes the compressor's usage of available energy. A capacitor is provided to smooth the power voltage and to provide additional current during compressor start-up. A controller monitors the rate of change of the smoothed power voltage to determine if the compressor is operating below or above the available power maximum, and adjusts the compressor speed accordingly. In this manner, the compressor operation is adjusted to convert substantially all available solar power into stored thermal energy.

  1. Direct condensation refrigerant recovery and restoration system

    SciTech Connect

    Grant, D.C.H.

    1992-03-10

    This patent describes a refrigerant recovery and purification system for removing gaseous refrigerant from a disabled refrigeration unit, cleaning the refrigerant of contaminants, and converting the gaseous refrigerant to a liquid state for storage. It comprises a low pressure inlet section; a high pressure storage section; the low pressure inlet section comprising: an oil and refrigerant gas separator, including a separated oil removal means, first conduit means for connecting an inlet of the separator to the disabled refrigerant unit, a slack-sided accumulator, second conduit means connecting the separator to the slack-sided accumulator, a reclaim condenser, third conduit means connecting the separator and the reclaim condenser in series, an evaporator coil in the reclaim condenser connectable to a conventional operating refrigeration system for receiving a liquid refrigerant under pressure for expansion therein, the evaporator coil forming a condensing surface for condensing the refrigerant gas at near atmospheric pressure in the condenser, a liquid receiver, a reclaimed refrigerant storage tank, fourth conduit means further connecting the liquid receiver in series with the reclaim condenser, downstream thereof, means between the reclaim condenser and the liquid receiver.

  2. Keeping Cool With Solar-Powered Refrigeration

    NASA Technical Reports Server (NTRS)

    2003-01-01

    In the midst of developing battery-free, solar-powered refrigeration and air conditioning systems for habitats in space, David Bergeron, the team leader for NASA's Advanced Refrigerator Technology Team at Johnson Space Center, acknowledged the need for a comparable solar refrigerator that could operate in conjunction with the simple lighting systems already in place on Earth. Bergeron, a 20-year veteran in the aerospace industry, founded the company Solus Refrigeration, Inc., in 1999 to take the patented advanced refrigeration technology he co-developed with his teammate, Johnson engineer Michael Ewert, to commercial markets. Now known as SunDanzer Refrigeration, Inc., Bergeron's company is producing battery-free, photovoltaic (PV) refrigeration systems under license to NASA, and selling them globally.

  3. A global three-dimensional study of the fate of HCFCs and HFC-134a in the troposphere

    NASA Astrophysics Data System (ADS)

    Kanakidou, Maria; Dentener, Frank J.; Crutzen, Paul J.

    1995-09-01

    We present the first attempt to use a global three-dimensional model of the troposphere to study the degradation chemistry of the alternative chlorofluoro- and fluorohydrocarbons HCFC-22, HCFC-123, HCFC-124, HFC-134a, HCFC-141b, and HCFC-142b and the main removal processes from the troposphere of these halogenated hydrocarbons and their oxidation products. Lifetimes of the parent hydrochlorofluorocarbons (HCFCs) and HFC-134a range from 1.3 to 20 years, with oxidation by the OH radical being the dominant removal process. Using the emission scenarios of McCulloch (1993), we calculate that HCFC-22 volume mixing ratios will reach a maximum of 190 parts per trillion by volume (pptv) around the year 2005, the mixing ratios of all other HCFCs remaining below 100 pptv. The chlorine loading potentials (CLP) of these HCFCs range from 0.014 for HCFC-123 to 0.166 for HCFC-142b, whereas HFC-134a has a zero CLP. Based on recent kinetic information, it is calculated that none of the relatively stable intermediate oxidation products such as COF2, COFCl, CF3COF, and CF3COCl will substantially build up in the atmosphere, the global abundances of these compounds being generally less than 1% those of the parent compounds. A possible exception is HCOF for which the heterogeneous removal parameters have not been experimentally determined. Hydrolysis in clouds, and to a lesser extent in seawater, is the process efficiently removing these species. Organic nitrates from all HCFCs studied will not reach substantial concentrations and will not contribute to chlorine delivery to the stratosphere. The deposition fluxes of the very stable trifluoroacetic acid (TFA), derived from the oxidation of HFC-134a and HCFCs-123 and 124, will reach in the year 2020 maximum levels of 2 ?mol/m2/yr (about 1 nmol/L rainwater). Maximum deposition occurs in tropical regions, associated with high oxidation rates of the parent compounds, and high rainfall. These predicted concentrations and deposition fluxes are orders of magnitude smaller than what is thought to be toxic for humans, for the fauna, and for the flora.

  4. 40 CFR Appendix D to Subpart B of... - SAE J2810 Standard for Recovery Only Equipment for HFC-134a Refrigerant

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., DC 20402-9320. CFR 49, Section 173.304Shippers—General Requirements for Shipments and Packagings. 2.1...). This will ensure that the container meets Department of Transportation (DOT) Standard, CFR Title 49...: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), http://www.sae.org. SAE...

  5. Nelium, a Refrigerant with High Potential for the Temperature Range between 27 and 70 K

    NASA Astrophysics Data System (ADS)

    Quack, Hans; Haberstroh, Christoph; Seemann, Ilka; Klaus, Marcel

    In the search for the optimum process for the liquefaction of hydrogen, it was found that mixtures of helium and neon, called "Nelium", allow processes with very high efficiency compared to pure helium or pure neon. This is demonstrated in the design of a 500 kW refrigerator between 40 and 60 K, whereby the composition is varied between pure helium and pure neon. It turns out that helium-rich mixtures have an advantage for the heat exchange, whereas the neon-rich mixtures are easier to compress in turbo compressors. In any case a process efficiency of over 44% is feasible.

  6. Evaluation on environment-friendly refrigerants with similar normal boiling points in ejector refrigeration system

    NASA Astrophysics Data System (ADS)

    Wang, F.; Shen, S. Q.; Li, D. Y.

    2014-12-01

    Based on the "hypothetical throat area" theory and the "constant-pressure mixing" theory, a thermodynamic model for ejector was set up by introducing the real properties of refrigerants. Refrigerants which have similar normal boiling points with each other may act as replacement to each other in substitute progress. In this paper, eight environment-friendly refrigerants were divided into 4 pairs for study according to their normal boiling point. In each refrigerant pair, the entrainment ratios of ejector, system COP, pump power et al. of refrigerants were compared and analyzed. Lastly, the performances of the transcritical and subcritical ejector refrigeration cycles with propylene were calculated and compared.

  7. Dilution Refrigerator for Nuclear Refrigeration and Cryogenic Thermometry Studies

    NASA Astrophysics Data System (ADS)

    Nakagawa, Hisashi; Hata, Tohru

    2014-07-01

    This study explores the design and construction of an ultra-low temperature facility in order to realize the Provisional low-temperature scale from 0.9 mK to 1 K (PLTS-2000) in Japan, to disseminate its use through calibration services, and to study thermometry at low temperatures below 1 K. To this end, a dilution refrigerator was constructed in-house that has four sintered silver discrete heat exchangers for use as a precooling stage of a copper nuclear demagnetization stage. A melting curve thermometer attached to the mixing chamber flange could be cooled continuously to 4.0 mK using the refrigerator. The dependence of minimum temperatures on circulation rates can be explained by the calculation of Frossati's formula based on a perfect continuous counterflow heat exchanger model, assuming that the Kapitza resistance has a temperature dependence. Residual heat leakage to the mixing chamber was estimated to be around 86 nW. A nuclear demagnetization cryostat with a nuclear stage containing an effective amount of copper (51 mol in a 9 T magnetic field) is under construction, and we will presently start to work toward the realization of the PLTS-2000. In this article, the design and performance of the dilution refrigerator are reported.

  8. Study on the Materials for Compressor and Reliability of Refrigeration Circuit in Refrigerator with R134a Refrigerant

    NASA Astrophysics Data System (ADS)

    Komatsubara, Takeo; Sunaga, Takasi; Takahasi, Yasuki

    R134a was selected as the alternative refrigerant for R12 because of the similar thermodynamic properties with R12. But refrigeration oil for R12 couldn't be used for R134a because of the immiscibility with R134a. To solve this problem we researched miscible oil with R134a and selected polyol ester oil (POE) as refrigeration oil. But we found sludge deposition into capillary tube after life test of refrigerator with POE and detected metal soap, decomposed oil and alkaline ions by analysis of sludge. This results was proof of phenomena like oil degradation, precipitation of process materials and wear of compressor. Therefore we improved stability and lubricity of POE, reevaluated process materials and contaminations in refrigerating circuit. In this paper we discuss newly developed these technologies and evaluation results of it by life test of refrigerator.

  9. Hybrid cryogenic refrigerator combining magnetic- and gas-cooling system

    NASA Astrophysics Data System (ADS)

    Yayama, Hideki; Hatta, Yoshiro; Tomokiyo, Akihisa

    2000-07-01

    We propose a new cryogenic refrigerator which is a hybrid of the Brayton magnetic-cooling cycle and the Gifford-McMahon (GM) gas-cooling cycle. We evaluate the refrigeration power of the refrigerator with an ErNi regenerator material by a numerical simulation. The results show a remarkably large refrigeration power in contrast to the conventional simple GM gas refrigerator.

  10. Mountain Plains Learning Experience Guide: Heating, Refrigeration, & Air Conditioning.

    ERIC Educational Resources Information Center

    Carey, John

    This Heating, Refrigeration, and Air Conditioning course is comprised of eleven individualized units: (1) Refrigeration Tools, Materials, and Refrigerant; (2) Basic Heating and Air Conditioning; (3) Sealed System Repairs; (4) Basic Refrigeration Systems; (5) Compression Systems and Compressors; (6) Refrigeration Controls; (7) Electric Circuit…

  11. Quantum-enhanced absorption refrigerators

    PubMed Central

    Correa, Luis A.; Palao, José P.; Alonso, Daniel; Adesso, Gerardo

    2014-01-01

    Thermodynamics is a branch of science blessed by an unparalleled combination of generality of scope and formal simplicity. Based on few natural assumptions together with the four laws, it sets the boundaries between possible and impossible in macroscopic aggregates of matter. This triggered groundbreaking achievements in physics, chemistry and engineering over the last two centuries. Close analogues of those fundamental laws are now being established at the level of individual quantum systems, thus placing limits on the operation of quantum-mechanical devices. Here we study quantum absorption refrigerators, which are driven by heat rather than external work. We establish thermodynamic performance bounds for these machines and investigate their quantum origin. We also show how those bounds may be pushed beyond what is classically achievable, by suitably tailoring the environmental fluctuations via quantum reservoir engineering techniques. Such superefficient quantum-enhanced cooling realises a promising step towards the technological exploitation of autonomous quantum refrigerators. PMID:24492860

  12. Suction muffler for refrigeration compressor

    DOEpatents

    Nelson, R.T.; Middleton, M.G.

    1983-01-25

    A hermetic refrigeration compressor includes a suction muffler formed from two pieces of plastic material mounted on the cylinder housing. One piece is cylindrical in shape with an end wall having an aperture for receiving a suction tube connected to the cylinder head. The other piece fits over and covers the other end of the cylindrical piece, and includes a flaring entrance horn which extends toward the return line on the sidewall of the compressor shell. 5 figs.

  13. Suction muffler for refrigeration compressor

    DOEpatents

    Nelson, Richard T. (Worthington, OH); Middleton, Marc G. (West Jefferson, OH)

    1983-01-01

    A hermetic refrigeration compressor includes a suction muffler formed from two pieces of plastic material mounted on the cylinder housing. One piece is cylindrical in shape with an end wall having an aperture for receiving a suction tube connected to the cylinder head. The other piece fits over and covers the other end of the cylindrical piece, and includes a flaring entrance horn which extends toward the return line on the sidewall of the compressor shell.

  14. Magnetic refrigerator for hydrogen liquefaction

    NASA Astrophysics Data System (ADS)

    Numazawa, T.; Kamiya, K.; Utaki, T.; Matsumoto, K.

    2014-07-01

    This paper reviews the status of magnetic refrigeration system for hydrogen liquefaction. There is no doubt that hydrogen is one of most important energy sources in the near future. In particular, liquid hydrogen can be utilized for infrastructure construction consisting of storage and transportation. When we compare the consuming energy of hydrogen liquefaction with high pressurized hydrogen gas, FOM must be larger than 0.57 for hydrogen liquefaction. Thus, we need to develop a highly efficient liquefaction method. Magnetic refrigeration using the magneto-caloric effect has potential to realize not only the higher liquefaction efficiency >50%, but also to be environmentally friendly and cost effective. Our hydrogen magnetic refrigeration system consists of Carnot cycle for liquefaction stage and AMR (active magnetic regenerator) cycle for precooling stages. For the Carnot cycle, we develop the high efficient system with >80% liquefaction efficiency by using the heat pipe. For the AMR cycle, we studied two kinds of displacer systems, which transferred the working fluid. We confirmed the AMR effect with the cooling temperature span of 12 K for 1.8 T of the magnetic field and 6 s of the cycle. By using the simulation, we estimate the efficiency of the hydrogen liquefaction plant for 10 kg/day. A FOM of 0.47 is obtained for operation temperature between 20 K and 77 K including LN2 work input.

  15. 16 CFR 305.11 - Labeling for refrigerators, refrigerator-freezers, freezers, dishwashers, clothes washers, water...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...heaters, room air conditioners, and pool heaters. (a) Layout. All energy labels for refrigerators, refrigerator-freezers...labels appearing at the end of this part illustrating the basis layout. All positioning, spacing, type sizes, and line...

  16. 16 CFR 305.11 - Labeling for refrigerators, refrigerator-freezers, freezers, dishwashers, clothes washers, water...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...heaters, room air conditioners, and pool heaters. (a) Layout . All energy labels for refrigerators, refrigerator-freezers...labels appearing at the end of this part illustrating the basis layout. All positioning, spacing, type sizes, and line...

  17. Compatibility of refrigerants and lubricants with elastomers

    SciTech Connect

    Hamed, G.R.; Seiple, R.H.

    1992-07-01

    Information contained in this reporters designed to assist the air-conditioning and refrigeration industry in the selection of suitable elastomeric gasket and seal materials that will prove useful in various refrigerant and refrigeration lubricant environments. Swell measurements have been made on approximately 50% of the proposed elastomers (94 total)in both the lubricant (7 total) and refrigerant (10 total) materials. Swell behavior in the these fluids have been determined using weight and in situ diameter measurements for the refrigerants and weight, diameter and thickness measurements for the lubricants. Weight and diameter measurements are repeated after 2 hours and 24 hours for samples removed from the refrigerant test fluids and 24 hours after removal from the lubricants.

  18. Solid-vapor adsorption refrigeration system development

    NASA Astrophysics Data System (ADS)

    Rockenfeller, U.; Kirol, L.; Graebel, B.

    1991-12-01

    The study describes the development of heat-activated industrial refrigeration systems using ammoniated complex compound sorption media. The focus was on single-stage cycles for low temperature (+20 F and below) refrigeration. Compared to vapor compression refrigeration, these cycles have the advantages of lower operating energy costs, reduction of peak electrical demand and associated demand charges, and reduced maintenance costs due to replacement of the compressor with solid-state sorbers. In many cases, particularly for refrigeration at -40 F and below, complex compound sorption cycles also have the potential for lower first cost than conventional electrically driven refrigeration systems. Technical issues addressed included the following: economic optimization of sorber design, demonstration of cyclic stability of the sorption reactions, construction material compatibility, and reactor scale-up. Sorption reactions for refrigeration at -40 and -70 F were demonstrated. Optimum heat exchanger configuration, complex compound loading, and cycle time were determined.

  19. A novel refrigerator attaining temperature below ? point

    NASA Astrophysics Data System (ADS)

    Zhou, Yuan; Xue, XiaoDai; Wang, JunJie; Gu, Chao

    2012-08-01

    The present study proposes a novel refrigerator in theory, which uses 4He as working fluid to directly reach 2.3 K and uses a small amount of 3He to attain the temperature below 1.7 K. The compact and highly efficient new refrigerator works with the Vuilleumier cycle. The novel refrigerator is driven by a thermal compressor which creatively uses mix-refrigerants J-T refrigerator alternative to liquid nitrogen as the power source. Furthermore, the Vuilleumier cycle can be used to achieve temperature below liquid helium with the improvement of the ultra-low temperature regenerator material. A new method of reaching the temperature below 1.7 K is proposed on the regenerative refrigerator, which could be an important breakthrough for the cryogenic science and technology.

  20. High-Performance, Low Environmental Impact Refrigerants

    NASA Technical Reports Server (NTRS)

    McCullough, E. T.; Dhooge, P. M.; Glass, S. M.; Nimitz, J. S.

    2001-01-01

    Refrigerants used in process and facilities systems in the US include R-12, R-22, R-123, R-134a, R-404A, R-410A, R-500, and R-502. All but R-134a, R-404A, and R-410A contain ozone-depleting substances that will be phased out under the Montreal Protocol. Some of the substitutes do not perform as well as the refrigerants they are replacing, require new equipment, and have relatively high global warming potentials (GWPs). New refrigerants are needed that addresses environmental, safety, and performance issues simultaneously. In efforts sponsored by Ikon Corporation, NASA Kennedy Space Center (KSC), and the US Environmental Protection Agency (EPA), ETEC has developed and tested a new class of refrigerants, the Ikon (registered) refrigerants, based on iodofluorocarbons (IFCs). These refrigerants are nonflammable, have essentially zero ozone-depletion potential (ODP), low GWP, high performance (energy efficiency and capacity), and can be dropped into much existing equipment.

  1. Solar refrigeration - Study of dry absorption

    NASA Astrophysics Data System (ADS)

    Flechon, J.; Machizaud, F.

    Because the severe conditions imposed by ambient temperatures on solar refrigeration equipment in the tropics limit the choice of an absorption system, the thermokinetic characteristics of a calcium chloride/ammonia absorption cycle were examined. The refrigeration equipment employed works in two stages: vaporization and condensation of ammonia during the day and regeneration during the night. It is concluded that the refrigeration aparatus will be too cumbersome to serve as a portable system.

  2. Solid-Vapor Sorption Refrigeration Systems 

    E-print Network

    Graebel, W.; Rockenfeller, U.; Kirol, L.

    1991-01-01

    carbon cycles. Reaction rates have been measured for refrigeration cycles down to -70?F and found to be satisfactory for commercial use. The achievement of refrigeration at almost any desired firing-reject-cooling temperature combination is possible... much higher. This high energy combined with high refrigerant mass utilization results in extremely large energy densities. Thousands of complex compounds exist, and almost any desired vapor pressure temperature relationship is available. Figure 1...

  3. The characteristics of polytropic magnetic refrigeration cycles

    SciTech Connect

    Yan, Z.; Chen, J. , P.O. Box 8730, Beijing 100080 Department of Physics, Xiamen University, Xiamen, Fujian )

    1991-08-15

    The concepts of generalized polytropic processes and polytropic refrigeration cycles, which consist of two isothermal processes and two generalized polytropic processes of paramagnetic salt, are introduced. It is shown that such a class of general magnetic refrigeration cycles, which includes the Carnot, Stirling, and other useful magnetic refrigeration cycles, possesses the conditions of perfect regeneration and can have the same coefficient of performance as the Carnot cycle for the same temperature range. Thus, they have many applications in the research and manufacture of magnetic refrigerators.

  4. Heat Transfer Problems of Mixed Refrigerants

    NASA Astrophysics Data System (ADS)

    Fujii, Tetsu; Koyama, Shigeru; Goto, Masao; Takamatsu, Hiroshi

    From the point of view of the application of non-azeotropic mixed refrigerants to heat pump and refrigeration cycles, literatures on condensation and evaporation are surveyed and future problems to be studied are extracted. All researches on the relevant problems are recently started and still in developing way except for condensation on a single horizontal tube. Particularly, the studies for condensation and evaporation of mixed Freon refrigerant in a horizontal tube, which are the most important in practice, are far backward in comparison with single component refrigerant in every point of heat transfer characteristics, flow pattern and theoretical analysis.

  5. Magnon-driven quantum dot refrigerators

    NASA Astrophysics Data System (ADS)

    Wang, Yuan; Huang, Chuankun; Liao, Tianjun; Chen, Jincan

    2015-12-01

    A new model of refrigerator consisting of a spin-splitting quantum dot coupled with two ferromagnetic reservoirs and a ferromagnetic insulator is proposed. The rate equation is used to calculate the occupation probabilities of the quantum dot. The expressions of the electron and magnon currents are obtained. The region that the system can work in as a refrigerator is determined. The cooling power and coefficient of performance (COP) of the refrigerator are derived. The influences of the magnetic field, applied voltage, and polarization of two leads on the performance are discussed. The performances of two different magnon-driven quantum dot refrigerators are compared.

  6. Global and regional emissions estimates of 1,1-difluoroethane (HFC-152a, CH3CHF2) from in situ and air archive observations

    NASA Astrophysics Data System (ADS)

    Simmonds, P. G.; Rigby, M.; Manning, A. J.; Lunt, M. F.; O'Doherty, S.; Young, D.; McCulloch, A.; Fraser, P. J.; Henne, S.; Vollmer, M. K.; Reimann, S.; Wenger, A.; Mühle, J.; Harth, C. M.; Salameh, P. K.; Arnold, T.; Weiss, R. F.; Krummel, P. B.; Steele, L. P.; Dunse, B. L.; Miller, B. R.; Lunder, C. R.; Hermansen, O.; Schmidbauer, N.; Saito, T.; Yokouchi, Y.; Park, S.; Li, S.; Yao, B.; Zhou, L. X.; Arduini, J.; Maione, M.; Wang, R. H. J.; Prinn, R. G.

    2015-08-01

    High frequency, ground-based, in situ measurements from eleven globally-distributed sites covering 1994-2014, combined with measurements of archived air samples dating from 1978 onward and atmospheric transport models, have been used to estimate the growth of 1,1-difluoroethane (HFC-152a, CH3CHF2) mole fractions in the atmosphere and the global emissions required to derive the observed growth. HFC-152a is a significant greenhouse gas but since it does not contain chlorine or bromine, HFC-152a makes no direct contribution to the destruction of stratospheric ozone and is therefore used as a substitute for the ozone depleting chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs). HFC-152a has exhibited substantial atmospheric growth since the first measurements reaching a maximum annualised global growth rate of 0.81 ± 0.05 ppt yr-1 in 2006, implying a substantial increase in emissions up to 2006. However, since 2007, the annualised rate of growth has slowed to 0.38 ± 0.04 ppt yr-1 in 2010 with a further decline to an average rate of change in 2013-2014 of -0.06 ± 0.05 ppt yr-1. The average Northern Hemisphere (NH) mixing ratio in 1994 was 1.2 ppt rising to a mixing ratio of 10.2 ppt in December 2014. Average annual mixing ratios in the Southern Hemisphere (SH) in 1994 and 2014 were 0.34 and 4.4 ppt, respectively. We estimate global emissions of HFC-152a have risen from 7.3 ± 5.6 Gg yr-1 in 1994 to a maximum of 54.4 ± 17.1 Gg yr-1 in 2011, declining to 52.5 ± 20.1 Gg yr-1 in 2014 or 7.2 ± 2.8 Tg-CO2 eq yr-1. Analysis of mixing ratio enhancements above regional background atmospheric levels suggests substantial emissions from North America, Asia and Europe. Global HFC emissions (so called "bottom up" emissions) reported by the United Nations Framework Convention on Climate Change (UNFCCC) are based on cumulative national emission data reported to the UNFCCC, which in turn are based on national consumption data. There appears to be a significant underestimate of "bottom-up" global emissions of HFC-152a, possibly arising from largely underestimated USA emissions and undeclared Asian emissions.

  7. 49 CFR 179.102-1 - Carbon dioxide, refrigerated liquid.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Carbon dioxide, refrigerated liquid. 179...114 and 120) § 179.102-1 Carbon dioxide, refrigerated liquid. (a) Tank cars used to transport carbon dioxide, refrigerated liquid...

  8. 49 CFR 179.102-1 - Carbon dioxide, refrigerated liquid.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Carbon dioxide, refrigerated liquid. 179...114 and 120) § 179.102-1 Carbon dioxide, refrigerated liquid. (a) Tank cars used to transport carbon dioxide, refrigerated liquid...

  9. 49 CFR 179.102-1 - Carbon dioxide, refrigerated liquid.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Carbon dioxide, refrigerated liquid. 179...114 and 120) § 179.102-1 Carbon dioxide, refrigerated liquid. (a) Tank cars used to transport carbon dioxide, refrigerated liquid...

  10. 49 CFR 179.102-1 - Carbon dioxide, refrigerated liquid.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Carbon dioxide, refrigerated liquid. 179...114 and 120) § 179.102-1 Carbon dioxide, refrigerated liquid. (a) Tank cars used to transport carbon dioxide, refrigerated liquid...

  11. ALTERNATIVE TECHNOLOGIES FOR REFRIGERATION AND AIR-CONDITIONING APPLICATIONS

    EPA Science Inventory

    The report gives results of an assessment of refrigeration technologies that are alternatives to vapor compression refrigeration for use in five application categories: domestic air conditioning, commercial air conditioning, mobile air conditioning, domestic refrigeration, and co...

  12. Layer of protection analysis applied to ammonia refrigeration systems 

    E-print Network

    Zuniga, Gerald Alexander

    2009-05-15

    Ammonia refrigeration systems are widely used in industry. Demand of these systems is expected to increase due to the advantages of ammonia as refrigerant and because ammonia is considered a green refrigerant. Therefore, it is important to evaluate...

  13. 49 CFR 179.102-17 - Hydrogen chloride, refrigerated liquid.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Hydrogen chloride, refrigerated liquid...114 and 120) § 179.102-17 Hydrogen chloride, refrigerated liquid. Each tank car used to transport hydrogen chloride, refrigerated liquid...

  14. 49 CFR 179.102-17 - Hydrogen chloride, refrigerated liquid.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Hydrogen chloride, refrigerated liquid...114 and 120) § 179.102-17 Hydrogen chloride, refrigerated liquid. Each tank car used to transport hydrogen chloride, refrigerated liquid...

  15. 49 CFR 179.102-17 - Hydrogen chloride, refrigerated liquid.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Hydrogen chloride, refrigerated liquid...114 and 120) § 179.102-17 Hydrogen chloride, refrigerated liquid. Each tank car used to transport hydrogen chloride, refrigerated liquid...

  16. 49 CFR 179.102-17 - Hydrogen chloride, refrigerated liquid.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Hydrogen chloride, refrigerated liquid...114 and 120) § 179.102-17 Hydrogen chloride, refrigerated liquid. Each tank car used to transport hydrogen chloride, refrigerated liquid...

  17. 49 CFR 179.102-1 - Carbon dioxide, refrigerated liquid.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Carbon dioxide, refrigerated liquid. 179...and 120) § 179.102-1 Carbon dioxide, refrigerated liquid. (a) Tank cars used to transport carbon dioxide, refrigerated liquid must...

  18. 46 CFR 130.230 - Protection from refrigerants.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...230 Protection from refrigerants. (a) For each refrigeration system that exceeds 0.6 cubic meters (20 cubic...stowed convenient to, but outside, the space containing the refrigeration equipment. (c) A complete recharge in the form...

  19. 46 CFR 130.230 - Protection from refrigerants.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...230 Protection from refrigerants. (a) For each refrigeration system that exceeds 0.6 cubic meters (20 cubic...stowed convenient to, but outside, the space containing the refrigeration equipment. (c) A complete recharge in the form...

  20. 46 CFR 58.20-15 - Installation of refrigerating machinery.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS Refrigeration Machinery § 58.20-15 Installation of refrigerating...control device located outside the compartment. (c) All refrigeration compressor spaces shall be effectively ventilated and...

  1. 46 CFR 58.20-15 - Installation of refrigerating machinery.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS Refrigeration Machinery § 58.20-15 Installation of refrigerating...control device located outside the compartment. (c) All refrigeration compressor spaces shall be effectively ventilated and...

  2. 46 CFR 58.20-15 - Installation of refrigerating machinery.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS Refrigeration Machinery § 58.20-15 Installation of refrigerating...control device located outside the compartment. (c) All refrigeration compressor spaces shall be effectively ventilated and...

  3. 46 CFR 130.230 - Protection from refrigerants.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...230 Protection from refrigerants. (a) For each refrigeration system that exceeds 0.6 cubic meters (20 cubic...stowed convenient to, but outside, the space containing the refrigeration equipment. (c) A complete recharge in the form...

  4. 46 CFR 130.230 - Protection from refrigerants.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...230 Protection from refrigerants. (a) For each refrigeration system that exceeds 0.6 cubic meters (20 cubic...stowed convenient to, but outside, the space containing the refrigeration equipment. (c) A complete recharge in the form...

  5. 46 CFR 58.20-15 - Installation of refrigerating machinery.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS Refrigeration Machinery § 58.20-15 Installation of refrigerating...control device located outside the compartment. (c) All refrigeration compressor spaces shall be effectively ventilated and...

  6. 46 CFR 130.230 - Protection from refrigerants.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...230 Protection from refrigerants. (a) For each refrigeration system that exceeds 0.6 cubic meters (20 cubic...stowed convenient to, but outside, the space containing the refrigeration equipment. (c) A complete recharge in the form...

  7. Performance analysis of small capacity liquid nitrogen generator based on Joule-Thomson refrigerator coupled with air separation membrane

    NASA Astrophysics Data System (ADS)

    Piotrowska-Hajnus, Agnieszka; Chorowski, Maciej

    2012-06-01

    Joule - Thomson small capacity refrigerators supplied with gas mixture are studied theoretically and experimentally for a variety of applications. They can be especially promising when coupled with membrane air separators. We present liquid nitrogen generation system based on Joule - Thomson cooler joined with air separation membrane. Hollow fiber membrane is used for nitrogen separation from compressed and purified atmospheric air. Joule-Thomson refrigerator operates with a dedicated nitrogen - hydrocarbons mixture and provides a cooling power used for the separated nitrogen liquefaction. Special attention has been paid to a heat exchanger coupling the Joule- Thomson refrigerator with the membrane air separator. This paper describes the system design, the procedure of its working parameters optimization and tests results.

  8. Preliminary evaluation of tensile and stress-rupture behavior of W + 24 at. pct Re + 0. 4 at. pct HfC wire

    SciTech Connect

    Yun, H.M. )

    1993-01-01

    The tensile properties of hafnium carbide-dispersed tungsten-rhenium alloy wire, W + 24 at. pct Re + 0.4 at. pct HfC (W24ReHfC), were studied from liquid nitrogen temperature (LN[sub 2]) to 1750 K and its stress-rupture behavior determined from 1144 to 1500 K. These results are compared to previous data on W + 4 at. pct Re + 0.4 at. pct HfC (W4ReHfc) and W + 0.4 at. pct HfC (WHfC) wire. The room-temperature (RT) tensile strength of the W24ReHfC wire was about 3250 MPa and higher than that of the W4ReHfC (3160 MPa) and WHfC (2250 MPa) wires. The RT ductility of the W24ReHfC wire was quite high with a 50 pct reduction of area, whereas the W4ReHfC wire and the WHfC wire had RT ductilities of 28 and 2 pct, respectively. At temperatures of 1144 to 1366 K, the W24ReHfC wire had tensile strengths favorably comparable to the W4ReHfC and WHfC wires. However, above 1366 K, the W4ReHfC wire had both a greater tensile strength and stress-rupture strength than the W24ReHfC wire. The main contributions to the strengthening of the W24ReHfC wire were the fine and elongated fibrous grain microstructures and the dispersion of the HfC particles in the W-Re matrix. These properties suggested that the W24ReHfC wires hold promise as potential fiber reinforcements in composites from RT to about 1350 K.

  9. Improvement of the Performance for an Absorption Refrigeration System with Lithium bromide-water as Refrigerant by Increasing Absorption Pressure 

    E-print Network

    Xie, G.; Sheng, G.; Li, G.; Pan, S.

    2006-01-01

    Because the absorption refrigeration system uses the Lithium bromide- water solution as refrigerant, it is profitable for the environment that human beings are living since the values of ODP and GWP of the refrigerant almost are zero. However...

  10. Growth characteristics of Listeria monocytogenes as affected by a -native microflora in cooked ham under refrigerated and temperature abuse conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study examined the growth characteristics of L. monocytogenes as affected by a native microflora in cooked ham at refrigerated and abuse temperatures. A five-strain mixture of L. monocytogenes and a native microflora isolated from cooked meat were inoculated alone (monocultured) or co-inoculate...

  11. A PERFORMANCE EVALUATION OF A VARIABLE SPEED, MIXED REFRIGERANT HEAT PUMP. SUMMARY. EPA/600/SR-92/053

    EPA Science Inventory

    The performance of an innovative heat pump, equipped with a distillation column to shift the composition of a zeotropic refrigerant mixture, was evaluated. The results of U.S. Department of Energy (DOE) rating tests and seasonal energy calcuations are reported with the main cycl...

  12. Seven-effect absorption refrigeration

    DOEpatents

    DeVault, Robert C. (Knoxville, TN); Biermann, Wendell J. (Fayetteville, NY)

    1989-01-01

    A seven-effect absorption refrigeration cycle is disclosed utilizing three absorption circuits. In addition, a heat exchanger is used for heating the generator of the low absorption circuit with heat rejected from the condenser and absorber of the medium absorption circuit. A heat exchanger is also provided for heating the generator of the medium absorption circuit with heat rejected from the condenser and absorber of the high absorption circuit. If desired, another heat exchanger can also be provided for heating the evaporator of the high absorption circuit with rejected heat from either the condenser or absorber of the low absorption circuit.

  13. Seven-effect absorption refrigeration

    DOEpatents

    DeVault, R.C.; Biermann, W.J.

    1989-05-09

    A seven-effect absorption refrigeration cycle is disclosed utilizing three absorption circuits. In addition, a heat exchanger is used for heating the generator of the low absorption circuit with heat rejected from the condenser and absorber of the medium absorption circuit. A heat exchanger is also provided for heating the generator of the medium absorption circuit with heat rejected from the condenser and absorber of the high absorption circuit. If desired, another heat exchanger can also be provided for heating the evaporator of the high absorption circuit with rejected heat from either the condenser or absorber of the low absorption circuit. 1 fig.

  14. Influence of Refrigerant Mass Fraction in the Performance of an Ammonia Absorption Refrigerator

    NASA Astrophysics Data System (ADS)

    Takeshita, Keisuke; Amano, Yoshiharu; Hashizume, Takumi; Takei, Toshitaka; Tomizawa, Masao

    The performance of the rectifying column affects the coefficient of performance (COP) of an ammonia absorption refrigerator. Ammonia mass fraction of refrigerant is one of the key parameters indicating the performance of the rectifying column. We propose a method to estimate the refrigerant mass fraction with mass and energy balance equations around the separator at the inlet of the evaporator, and describe the results of experiments which measured the refrigerant mass fraction by sampling from the refrigerant receiver. Throughout these investigations, the refrigerant mass fraction turned out to be lower than the expected value calculated from the condition of dry-saturated vapor at the top of the rectifying column. The refrigerant mass fraction can be estimated within an accuracy of 0.3% by the estimation method based on mass and energy balance equations.

  15. 46 CFR 154.702 - Refrigerated carriage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Pressure and Temperature Control § 154.702 Refrigerated carriage. (a) Each refrigeration system must: (1) Have enough capacity to maintain the cargo vapor pressure in each cargo tank served by the system below the set pressure of the relief valves under ambient temperatures of 45 °C (113 °F) still air and 32...

  16. 46 CFR 154.702 - Refrigerated carriage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Pressure and Temperature Control § 154.702 Refrigerated carriage. (a) Each refrigeration system must: (1) Have enough capacity to maintain the cargo vapor pressure in each cargo tank served by the system below the set pressure of the relief valves under ambient temperatures of 45 °C (113 °F) still air and 32...

  17. 46 CFR 154.702 - Refrigerated carriage.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Pressure and Temperature Control § 154.702 Refrigerated carriage. (a) Each refrigeration system must: (1) Have enough capacity to maintain the cargo vapor pressure in each cargo tank served by the system below the set pressure of the relief valves under ambient temperatures of 45 °C (113 °F) still air and 32...

  18. 46 CFR 154.702 - Refrigerated carriage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Pressure and Temperature Control § 154.702 Refrigerated carriage. (a) Each refrigeration system must: (1) Have enough capacity to maintain the cargo vapor pressure in each cargo tank served by the system below the set pressure of the relief valves under ambient temperatures of 45 °C (113 °F) still air and 32...

  19. 46 CFR 154.702 - Refrigerated carriage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Pressure and Temperature Control § 154.702 Refrigerated carriage. (a) Each refrigeration system must: (1) Have enough capacity to maintain the cargo vapor pressure in each cargo tank served by the system below the set pressure of the relief valves under ambient temperatures of 45 °C (113 °F) still air and 32...

  20. 21 CFR 1250.34 - Refrigeration equipment.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... SANITATION Food Service Sanitation on Land and Air Conveyances, and Vessels § 1250.34 Refrigeration equipment... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Refrigeration equipment. 1250.34 Section 1250.34 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

  1. 21 CFR 1250.34 - Refrigeration equipment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... SANITATION Food Service Sanitation on Land and Air Conveyances, and Vessels § 1250.34 Refrigeration equipment... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Refrigeration equipment. 1250.34 Section 1250.34 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

  2. 21 CFR 1250.34 - Refrigeration equipment.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... SANITATION Food Service Sanitation on Land and Air Conveyances, and Vessels § 1250.34 Refrigeration equipment... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Refrigeration equipment. 1250.34 Section 1250.34 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

  3. 21 CFR 1250.34 - Refrigeration equipment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... SANITATION Food Service Sanitation on Land and Air Conveyances, and Vessels § 1250.34 Refrigeration equipment... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Refrigeration equipment. 1250.34 Section 1250.34 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

  4. 21 CFR 1250.34 - Refrigeration equipment.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... SANITATION Food Service Sanitation on Land and Air Conveyances, and Vessels § 1250.34 Refrigeration equipment... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Refrigeration equipment. 1250.34 Section 1250.34 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

  5. DESIGN AND OPTIMIZATION OF A REFRIGERATION SYSTEM

    EPA Science Inventory

    The paper discusses the design and optimization of a refrigeration system, using a mathematical model of a refrigeration system modified to allow its use with the optimization program. he model was developed using only algebraic equations so that it could be used with the optimiz...

  6. The Thermodynamics of a Refrigeration System.

    ERIC Educational Resources Information Center

    Azevedo e Silva, J. F. M.

    1991-01-01

    An attempt to clarify the teaching of some of the concepts of thermodynamics through the observation of an experiment with an ordinary refrigeration system is presented. The cycle of operation in the refrigeration system and the individual processes in the cycle are described. (KR)

  7. Commercial Refrigeration Technology. Florida Vocational Program Guide.

    ERIC Educational Resources Information Center

    University of South Florida, Tampa. Dept. of Adult and Vocational Education.

    The program guide for commercial refrigeration technology courses in Florida identifies primary considerations for the organization, operation, and evaluation of a vocational education program. Following an occupational description for the job title for refrigeration mechanic, and its Dictionary of Occupational Titles code, are six sections…

  8. Sorption compressor/mechanical expander hybrid refrigeration

    NASA Technical Reports Server (NTRS)

    Jones, J. A.; Britcliffe, M.

    1987-01-01

    Experience with Deep Space Network (DSN) ground-based cryogenic refrigerators has proved the reliability of the basic two-stage Gifford-McMahon helium refrigerator. A very long life cryogenic refrigeration system appears possible by combining this expansion system or a turbo expansion system with a hydride sorption compressor in place of the usual motor driven piston compressor. To test the feasibility of this system, a commercial Gifford-McMahon refrigerator was tested using hydrogen gas as the working fluid. Although no attempt was made to optimize the system for hydrogen operation, the refrigerator developed 1.3 W at 30 K and 6.6 W at 60 K. The results of the test and of theoretical performances of the hybrid compressor coupled to these expansion systems are presented.

  9. Sorption compressor/mechanical expander hybrid refrigeration

    NASA Astrophysics Data System (ADS)

    Jones, J. A.; Britcliffe, M.

    1987-08-01

    Experience with Deep Space Network (DSN) ground-based cryogenic refrigerators has proved the reliability of the basic two-stage Gifford-McMahon helium refrigerator. A very long life cryogenic refrigeration system appears possible by combining this expansion system or a turbo expansion system with a hydride sorption compressor in place of the usual motor driven piston compressor. To test the feasibility of this system, a commercial Gifford-McMahon refrigerator was tested using hydrogen gas as the working fluid. Although no attempt was made to optimize the system for hydrogen operation, the refrigerator developed 1.3 W at 30 K and 6.6 W at 60 K. The results of the test and of theoretical performances of the hybrid compressor coupled to these expansion systems are presented.

  10. A rocket-borne He-3 refrigerator

    NASA Technical Reports Server (NTRS)

    Duband, L.; Alsop, D.; Lange, A.; Kittel, P.

    1990-01-01

    A self-contained, recyclable He-3 refrigerator suitable for use in space has been developed. The refrigerator is compact, has no moving parts, and requires only electrical connections and thermal contact in order to operate from a 2 K cold stage. A charcoal adsorption pump is used to efficiently condense and cool the He-3. Sintered copper confines the He-3 to the evaporator in zero-gravity and, in fact, allows the refrigerator to operate upside-down in the laboratory. Mounted on a 2 K cold stage, the refrigerator provides 100 microwatts of cooling power at 346 mK, with a 7 hour hold time. On a 1.5 K cold stage, the lowest temperature achieved is 277 mK. The refrigerator has been vibration tested at 7.5 G amplitude from 30 to 400 Hz and 15 G amplitude from 400 to 2000 Hz.

  11. Compatibility of refrigerants and lubricants with elastomers

    SciTech Connect

    Hamed, G.R.; Seiple, R.H.

    1992-10-01

    Information contained in this report is designed to assist the air-conditioning and refrigeration industry in the selection of suitable elastomeric gasket and seal materials that will prove useful in various refrigerant and refrigeration lubricant environments. 97% of the swell measurements have been made to date. The other 3% of the measurements are contingent on the availability of additional quantities of R-32. Swell behavior in the fluids have been determined using weight and in situ diameter measurements for the refrigerants and weight, diameter and thickness measurements for the lubricants. Weight and diameter measurements are repeated after 2 hours and 24 hours for samples removed from the refrigerant test fluids and 24 hours after removal from the lubricants.

  12. Dynamic simulation of a reverse Brayton refrigerator

    NASA Astrophysics Data System (ADS)

    Peng, N.; Lei, L. L.; Xiong, L. Y.; Tang, J. C.; Dong, B.; Liu, L. Q.

    2014-01-01

    A test refrigerator based on the modified Reverse Brayton cycle has been developed in the Chinese Academy of Sciences recently. To study the behaviors of this test refrigerator, a dynamic simulation has been carried out. The numerical model comprises the typical components of the test refrigerator: compressor, valves, heat exchangers, expander and heater. This simulator is based on the oriented-object approach and each component is represented by a set of differential and algebraic equations. The control system of the test refrigerator is also simulated, which can be used to optimize the control strategies. This paper describes all the models and shows the simulation results. Comparisons between simulation results and experimental data are also presented. Experimental validation on the test refrigerator gives satisfactory results.

  13. Counterflow absorber for an absorption refrigeration system

    DOEpatents

    Reimann, Robert C. (Lafayette, NY)

    1984-01-01

    An air-cooled, vertical tube absorber for an absorption refrigeration system is disclosed. Strong absorbent solution is supplied to the top of the absorber and refrigerant vapor is supplied to the bottom of the absorber to create a direct counterflow of refrigerant vapor and absorbent solution in the absorber. The refrigeration system is designed so that the volume flow rate of refrigerant vapor in the tubes of the absorber is sufficient to create a substantially direct counterflow along the entire length of each tube in the absorber. This provides several advantages for the absorber such as higher efficiency and improved heat transfer characteristics, and allows improved purging of non-condensibles from the absorber.

  14. Dynamic simulation of a reverse Brayton refrigerator

    SciTech Connect

    Peng, N.; Xiong, L. Y.; Dong, B.; Liu, L. Q.; Lei, L. L.; Tang, J. C.

    2014-01-29

    A test refrigerator based on the modified Reverse Brayton cycle has been developed in the Chinese Academy of Sciences recently. To study the behaviors of this test refrigerator, a dynamic simulation has been carried out. The numerical model comprises the typical components of the test refrigerator: compressor, valves, heat exchangers, expander and heater. This simulator is based on the oriented-object approach and each component is represented by a set of differential and algebraic equations. The control system of the test refrigerator is also simulated, which can be used to optimize the control strategies. This paper describes all the models and shows the simulation results. Comparisons between simulation results and experimental data are also presented. Experimental validation on the test refrigerator gives satisfactory results.

  15. Compatibility of refrigerants and lubricants with elastomers

    SciTech Connect

    Hamed, G.R.; Seiple, R.H.

    1993-01-01

    The information contained in this report is designed to assist the air-conditioning and refrigeration industry in the selection of suitable elastomeric gasket and seal materials that will prove useful in various refrigerant and refrigeration lubricant environments. 97% of the swell measurements have been made to date. The other 3% of the measurements are contingent on availability of additional R-32. Swell behavior in the fluids have been determined using weight and in situ diameter measurements for the refrigerants and weight, diameter and thickness measurements for the lubricants. Weight and diameter measurements are repeated after 2 and 24 hours for samples removed from the refrigerant test fluids and 24 hours after removal from the lubricants.

  16. Sorption Refrigeration / Heat Pump Cycles

    NASA Astrophysics Data System (ADS)

    Saha, Bidyut Baran; Alam, K. C. Amanul; Hamamoto, Yoshinori; Akisawa, Atsushi; Kashiwagi, Takao

    Over the past few decades there have been considerable efforts to use adsorption (solid/vapor) for cooling and heat pump applications, but intensified efforts were initiated only since the imposition of international restrictions on the production and use of CFCs (chlorofluorocarbons) and HCFCs (hydrochlorofluorocarbons). Up to now, only the desiccant evaporative cooling system of the open type has achieved commercial use, predominantly in the United States. Closed-type adsorption refrigeration and heat pump systems are rarely seen in the market, or are still in the laboratory testing stage. Promising recent development have been made in Japan for the use of porous metal hydrides and composite adsorbents. In this paper, a short description of adsorption theories along with an overview of present status and future development trends of thermally powered adsorption refrigeration cycles are outlined putting emphasis on experimental achievements. This paper also addressed some advanced absorption cycles having relatively higher COP, and also summarizes fundamental concepts of GAX cycles and various GAX cycles developed for heat pump applications.

  17. Novel materials for laser refrigeration

    SciTech Connect

    Hehlen, Markus P

    2009-01-01

    The status of optical refrigeration of rare-earth-doped solids is reviewed, and the various factors that limit the performance of current laser-cooling materials are discussed. Efficient optical refrigeration is possible in materials for which {Dirac_h}{omega}{sub max} < E{sub p}/8, where {Dirac_h}{omega}{sub max} is the maximum phonon energy of the host material and E{sub p} is the pump energy of the rare-earth dopant. Transition-metal and OH{sup -}impurities at levels >100 ppb are believed to be the main factors for the limited laser-cooling performance in current materials. The many components of doped ZBLAN glass pose particular processing challenges. Binary fluoride glasses such as YF{sub 3}-LiF are considered as alternatives to ZBLAN. The crystalline system KPb{sub 2}CI{sub 5} :Dy{sup 3+} is identified as a prime candidate for high-efficiency laser cooling.

  18. Impacts of advanced refrigerator insulation

    NASA Astrophysics Data System (ADS)

    Potter, T. F.; Benson, D. K.; Smith, L. K.

    1988-07-01

    Recent developments in advanced insulations, such as powders under a soft vacuum (R = 20 per inch), and hard-vacuum insulation with spacers (R = 15 per 0.1 inch), merit evaluating their practical uses. Refrigerator/freezers (R/Fs) are well-suited for incorporating the new insulations for the following reasons: the energy consumption of R/Fs must be reduced to comply with the National Appliance Energy Conservation Act (NAECA) standards; the Montreal Protocol to Control Ozone-Depleting Substances calls for a reduction in chlorofluorocarbons (CFCs) that are now used in the insulative foams in R/F sidewalls; and both high R-values to minimize heat gain through the walls, and thin walls to maximize the interior volume, are desirable. We selected two different R/F base-cases for this analysis; one had the typically used CFC foam (R = 7.7 per inch), while the other featured non-CFC foam (R = 5.3 per inch) in the exterior walls and doors. (In keeping with industry practice, both refrigerator doors were insulated with fiberglass.) Two simulated modifications of both of the base cases, based on the DOE closed-door test, included replacing part of the wall and door insulation with either 1 inch of powder or a 0.1 inch layer of hard vacuum/spacer insulation. Both of these modifications met the standard, even when the non-CFC foam base case was simulated.

  19. Oil cooled, hermetic refrigerant compressor

    DOEpatents

    English, William A. (Murrysville, PA); Young, Robert R. (Murrysville, PA)

    1985-01-01

    A hermetic refrigerant compressor having an electric motor and compressor assembly in a hermetic shell is cooled by oil which is first cooled in an external cooler 18 and is then delivered through the shell to the top of the motor rotor 24 where most of it is flung radially outwardly within the confined space provided by the cap 50 which channels the flow of most of the oil around the top of the stator 26 and then out to a multiplicity of holes 52 to flow down to the sump and provide further cooling of the motor and compressor. Part of the oil descends internally of the motor to the annular chamber 58 to provide oil cooling of the lower part of the motor, with this oil exiting through vent hole 62 also to the sump. Suction gas with entrained oil and liquid refrigerant therein is delivered to an oil separator 68 from which the suction gas passes by a confined path in pipe 66 to the suction plenum 64 and the separated oil drops from the separator to the sump. By providing the oil cooling of the parts, the suction gas is not used for cooling purposes and accordingly increase in superheat is substantially avoided in the passage of the suction gas through the shell to the suction plenum 64.

  20. Oil cooled, hermetic refrigerant compressor

    DOEpatents

    English, W.A.; Young, R.R.

    1985-05-14

    A hermetic refrigerant compressor having an electric motor and compressor assembly in a hermetic shell is cooled by oil which is first cooled in an external cooler and is then delivered through the shell to the top of the motor rotor where most of it is flung radially outwardly within the confined space provided by the cap which channels the flow of most of the oil around the top of the stator and then out to a multiplicity of holes to flow down to the sump and provide further cooling of the motor and compressor. Part of the oil descends internally of the motor to the annular chamber to provide oil cooling of the lower part of the motor, with this oil exiting through vent hole also to the sump. Suction gas with entrained oil and liquid refrigerant therein is delivered to an oil separator from which the suction gas passes by a confined path in pipe to the suction plenum and the separated oil drops from the separator to the sump. By providing the oil cooling of the parts, the suction gas is not used for cooling purposes and accordingly increase in superheat is substantially avoided in the passage of the suction gas through the shell to the suction plenum. 3 figs.

  1. Estimating Mixture Models via Mixtures of Polynomials

    E-print Network

    Pratt, Vaughan

    Estimating Mixture Models via Mixtures of Polynomials Sida I. Wang Arun Tejasvi Chaganty Percy,chaganty,pliang}@cs.stanford.edu Abstract Mixture modeling is a general technique for making any simple model more ex- pressive through Maximization (EM) algorithm, in which updates are easy to derive for a wide class of mixture models. However

  2. 46 CFR 130.230 - Protection from refrigerants.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... storage capacity if using a fluorocarbon, as a refrigerant, there must be available one pressure-demand... 46 Shipping 4 2010-10-01 2010-10-01 false Protection from refrigerants. 130.230 Section 130.230... refrigerants. (a) For each refrigeration system that exceeds 0.6 cubic meters (20 cubic feet) of...

  3. 46 CFR 130.230 - Protection from refrigerants.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... storage capacity if using a fluorocarbon, as a refrigerant, there must be available one pressure-demand... 46 Shipping 4 2011-10-01 2011-10-01 false Protection from refrigerants. 130.230 Section 130.230... refrigerants. (a) For each refrigeration system that exceeds 0.6 cubic meters (20 cubic feet) of...

  4. 46 CFR 151.40-11 - Refrigeration systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Refrigeration systems. 151.40-11 Section 151.40-11... Refrigeration systems. (a) Boiloff systems. The venting of cargo boiloff to atmosphere shall not be used as a...) Vapor compression, tank refrigeration, and secondary refrigeration systems: The required...

  5. Mixed refrigerant Joule-Thomson sorption cryocoolers

    NASA Astrophysics Data System (ADS)

    Tzabar, Nir; Grossman, Gershon

    2014-01-01

    Joule-Thomson (JT) sorption cryocooling is the most mature technology for cooling from a normal Room-Temperature (RT) down to temperatures below 100 K in the absence of moving parts. Therefore, high reliability and no vibrations are attainable, in comparison with other cryocoolers. Cooling to 80 - 100 K with JT cryocoolers is often implemented with pure nitrogen. Alternatively, mixed refrigerants have been suggested for reducing the operating pressures to enable closed cycle cryocooling. There is a variety of publications describing nitrogen sorption cryocoolers with different configurations of sorption compressors. In the present research we suggest a novel sorption JT cryocooler that operates with a mixed refrigerant. Merging of sorption cryocooling and a mixed refrigerant enables the use of a simple, single stage compressor for cooling to 80 - 100 K, lower operating temperatures of the sorption cycle, and thus - reduced power consumption. In previous studies we have analyzed sorption compressors for mixed gases and mixed refrigerants for JT cryocoolers, separately. In this paper the option of mixed refrigerant sorption JT cryocoolers is explored. The considerations for developing mixed refrigerants to be driven by sorption compressors and to be utilized with JT cryocoolers are provided. It appears that, unlike with pure nitrogen, mixed refrigerants can be suitable for JT cryocooling with a single stage sorption compressor.

  6. Dual-circuit, multiple-effect refrigeration system and method

    DOEpatents

    DeVault, Robert C. (Knoxville, TN)

    1995-01-01

    A dual circuit absorption refrigeration system comprising a high temperature single-effect refrigeration loop and a lower temperature double-effect refrigeration loop separate from one another and provided with a double-condenser coupling therebetween. The high temperature condenser of the single-effect refrigeration loop is double coupled to both of the generators in the double-effect refrigeration loop to improve internal heat recovery and a heat and mass transfer additive such as 2-ethyl-1-hexanol is used in the lower temperature double-effect refrigeration loop to improve the performance of the absorber in the double-effect refrigeration loop.

  7. Refrigerant charge management in a heat pump water heater

    DOEpatents

    Chen, Jie; Hampton, Justin W.

    2014-06-24

    Heat pumps that heat or cool a space and that also heat water, refrigerant management systems for such heat pumps, methods of managing refrigerant charge, and methods for heating and cooling a space and heating water. Various embodiments deliver refrigerant gas to a heat exchanger that is not needed for transferring heat, drive liquid refrigerant out of that heat exchanger, isolate that heat exchanger against additional refrigerant flowing into it, and operate the heat pump while the heat exchanger is isolated. The heat exchanger can be isolated by closing an electronic expansion valve, actuating a refrigerant management valve, or both. Refrigerant charge can be controlled or adjusted by controlling how much liquid refrigerant is driven from the heat exchanger, by letting refrigerant back into the heat exchanger, or both. Heat pumps can be operated in different modes of operation, and segments of refrigerant conduit can be interconnected with various components.

  8. Ferroelectric Stirling-Cycle Refrigerator

    NASA Technical Reports Server (NTRS)

    Jalink, Antony, Jr. (Inventor); Hellbaum, Richard F. (Inventor); Rohrbach, Wayne W. (Inventor)

    1999-01-01

    A Stirling-cycle refrigerator has a three-pump configuration and pumping sequence, in which one pump serves as a compressor. one pump serves as an expander, and one pump serves as a displacer. The pumps are ferroelectrically actuated diaphragm pumps which are coordinated by synchronizing the ferroelectric-actuator voltages in such a way that the net effect of the displacer is to reduce the deleterious effect of dead space; that is, to circulate a greater fraction of the working fluid through the heat exchangers than would be possible by use of the compressor and expander alone. In addition. the displacer can be controlled separately to make the flow of working fluid in the heat exchangers turbulent (to increase the rate of transfer of heat at the cost of greater resistance to flow) or laminar (to decrease the resistance to flow at the cost of a lower heat-transfer rate).

  9. Bearing construction for refrigeration compresssor

    DOEpatents

    Middleton, Marc G. (Wyoming, MI); Nelson, Richard T. (Worthington, OH)

    1988-01-01

    A hermetic refrigeration compressor has a cylinder block and a crankshaft rotatable about a vertical axis to reciprocate a piston in a cylinder on the cylinder block. A separate bearing housing is secured to the central portion of the cylinder block and extends vertically along the crankshaft, where it carries a pair of roller bearings to journal the crankshaft. The crankshaft has a radially extending flange which is journaled by a thrust-type roller bearing above the bearing housing to absorb the vertical forces on the crankshaft so that all three of the roller bearings are between the crankshaft and the bearing housing to maintain and control the close tolerances required by such bearings.

  10. Improved Regenerative Sorbent-Compressor Refrigerator

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.

    1992-01-01

    Conceptual regenerative sorbent-compressor refrigerator attains regeneration efficiency and, therefore, overall power efficiency and performance greater than conventional refrigerators. Includes two fluid loops. In one, CH2FCF3 (R134a) ciculates by physical adsorption and desorption in four activated-charcoal sorption compressors. In other, liquid or gas coolant circulated by pump. Wave of regenerative heating and cooling propagates cyclically like peristatic wave among sorption compressors and associated heat exchangers. Powered by electricity, oil, gas, solar heat, or waste heat. Used as air conditioners, refrigerators, and heat pumps in industrial, home, and automotive applications.

  11. Space shuttle orbiter mechanical refrigeration system

    NASA Technical Reports Server (NTRS)

    Williams, J. L.

    1974-01-01

    A radiator/condenser was designed which is efficient in both condensation (refrigeration) and liquid phase (radiator) operating modes, including switchover from the refrigeration mode to the radiator mode and vice versa. A method for predicting the pressure drop of a condensing two-phase flow in zero-gravity was developed along with a method for predicting the flow regime which would prevail along the condensation path. The hybrid refrigeration system was assembled with the two radiator/condenser panels installed in a space environment simulator. The system was tested under both atmospheric and vacuum conditions. Results of the tests are presented.

  12. Sorption cryogenic refrigeration - Status and future

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.

    1988-01-01

    The operation principles of sorption cryogenic refrigeration are discussed. Sorption refrigerators have virtually no wear-related moving parts, have negligible vibration, and offer extremely long life (at least ten years), making it possible to obtain efficient, long life and low vibration cooling to as low as 7 K for cryogenic sensors. The physisorption and chemisorption systems recommended for various cooling ranges down to 7 K are described in detail. For long-life cooling at 4-5 K temperatures, a hybrid chemisorption-mechanical refrigeration system is recommended.

  13. Compatibility of refrigerants and lubricants with engineering plastics

    SciTech Connect

    Cavestri, R.C.

    1993-01-01

    Seven oil immersion studies were completed at both 20 and 60C. Test bars used in this study fall within the manufacturer specification limits of physical consistency and integrity. Refrigerant Immersion studies at ambient and 60C are also complete. Equilibrium refrigerant gas solubilities of the 32 ISO VG branched acid polyolester with all ten refrigerants have been determined and completed at 20C. Finally, the thermal aging of plastics at constant refrigerant pressure exposure with seventeen refrigerant lubricant combinations have been completed.

  14. Compatibility of alternative refrigerants with varnished magnet wire

    SciTech Connect

    Doerr, R.; Kujak, S.

    1993-10-01

    The compatibility of 24 motor materials with 11 pure refrigerators and 17 refrigerant-lubricant combinations was determined. This is summary of the effect of refrigerants on varnished magnet wire. Of the refrigerants tested, exposure to HCFC-22 produced the most deleterious effects on the magnet wire insulation and varnishes. Since many of the materials tested have excellent reliability with HCFC-22 in current applications, these materials are expected to be reliable when used with new refrigerants.

  15. Purification and Liquefacttion of Neon Using a Helium Refrigeration Cycle

    NASA Astrophysics Data System (ADS)

    Boeck, S.

    2010-04-01

    The cryogenic plant developed by Linde Kryotechnik is used to extract neon out of a crude gas flow coming from an air separation plant. The crude gas is cooled down by a two stage helium refrigeration process using the Linde Kryotechnik dynamic gas bearing turbines. After the first cooling stage, nitrogen is liquefied and separated from the crude gas. The Cryogenic adsorbers located at a temperature level below 80 K clean the crude gas from remaining nitrogen traces before the neon-helium mixture enters the final cooling stage. In the second cooling stage neon is liquefied and separated from the helium. The final product quality will be achieved within a rectification column at low pressure level.

  16. U.S. emissions of HFC-134a derived for 2008-2012 from an extensive flask-air sampling network

    NASA Astrophysics Data System (ADS)

    Hu, Lei; Montzka, Stephen A.; Miller, John B.; Andrews, Aryln E.; Lehman, Scott J.; Miller, Benjamin R.; Thoning, Kirk; Sweeney, Colm; Chen, Huilin; Godwin, David S.; Masarie, Kenneth; Bruhwiler, Lori; Fischer, Marc L.; Biraud, Sebastien C.; Torn, Margaret S.; Mountain, Marikate; Nehrkorn, Thomas; Eluszkiewicz, Janusz; Miller, Scot; Draxler, Roland R.; Stein, Ariel F.; Hall, Bradley D.; Elkins, James W.; Tans, Pieter P.

    2015-01-01

    national and regional emissions of HFC-134a are derived for 2008-2012 based on atmospheric observations from ground and aircraft sites across the U.S. and a newly developed regional inverse model. Synthetic data experiments were first conducted to optimize the model assimilation design and to assess model-data mismatch errors and prior flux error covariances computed using a maximum likelihood estimation technique. The synthetic data experiments also tested the sensitivity of derived national and regional emissions to a range of assumed prior emissions, with the goal of designing a system that was minimally reliant on the prior. We then explored the influence of additional sources of error in inversions with actual observations, such as those associated with background mole fractions and transport uncertainties. Estimated emissions of HFC-134a range from 52 to 61 Gg yr-1 for the contiguous U.S. during 2008-2012 for inversions using air transport from Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model driven by the 12 km resolution meteorogical data from North American Mesoscale Forecast System (NAM12) and all tested combinations of prior emissions and background mole fractions. Estimated emissions for 2008-2010 were 20% lower when specifying alternative transport from Stochastic Time-Inverted Lagrangian Transport (STILT) model driven by the Weather Research and Forecasting (WRF) meteorology. Our estimates (for HYSPLIT-NAM12) are consistent with annual emissions reported by U.S. Environmental Protection Agency for the full study interval. The results suggest a 10-20% drop in U.S. national HFC-134a emission in 2009 coincident with a reduction in transportation-related fossil fuel CO2 emissions, perhaps related to the economic recession. All inversions show seasonal variation in national HFC-134a emissions in all years, with summer emissions greater than winter emissions by 20-50%.

  17. Preliminary evaluation of tensile and stress-rupture behavior of W + 24 At. Pct Re + 0.4 At. Pct HfC wire

    NASA Astrophysics Data System (ADS)

    Yun, H. M.

    1993-01-01

    The tensile properties of hafnium carbide-dispersed tungsten-rhenium alloy wire, W + 24 at. pct Re + 0.4 at. pct HfC (W24ReHfC), were studied from liquid nitrogen temperature (LN2) to 1750 K and its stress-rupture behavior determined from 1144 to 1500 K. These results are compared to previous data on W + 4 at. pct Re + 0.4 at. pct HfC (W4ReHfC) and W + 0.4 at. pct HfC (WHfC) wire.[5] The room-temperature (RT) tensile strength of the W24ReHfC wire was about 3250 MPa and higher than that of the W4ReHfC (3160 MPa) and WHfC (2250 MPa) wires. The RT ductility of the W24ReHfC wire was quite high with a 50 pct reduction of area, whereas the W4ReHfC wire and the WHfC wire had RT ductilities of 28 and 2 pct, respectively. At temperatures of 1144 to 1366 K, the W24ReHfC wire had tensile strengths favorably comparable to the W4ReHfC and WHfC wires. However, above 1366 K, the W4ReHfC wire had both a greater tensile strength and stress-rupture strength than the W24ReHfC wire. The main contributions to the strengthening of the W24ReHfC wire were the fine and elongated fibrous grain microstructures and the dispersion of the HfC particles in the W-Re matrix. These properties suggested that the W24ReHfC wires hold promise as potential fiber reinforcements in composites from RT to about 1350 K.

  18. Status of not-in-kind refrigeration technologies for household space conditioning, water heating and food refrigeration

    SciTech Connect

    Bansal, Pradeep; Vineyard, Edward Allan; Abdelaziz, Omar

    2012-01-01

    This paper presents a review of the next generation not-in-kind technologies to replace conventional vapor compression refrigeration technology for household applications. Such technologies are sought to provide energy savings or other environmental benefits for space conditioning, water heating and refrigeration for domestic use. These alternative technologies include: thermoacoustic refrigeration, thermoelectric refrigeration, thermotunneling, magnetic refrigeration, Stirling cycle refrigeration, pulse tube refrigeration, Malone cycle refrigeration, absorption refrigeration, adsorption refrigeration, and compressor driven metal hydride heat pumps. Furthermore, heat pump water heating and integrated heat pump systems are also discussed due to their significant energy saving potential for water heating and space conditioning in households. The paper provides a snapshot of the future R&D needs for each of the technologies along with the associated barriers. Both thermoelectric and magnetic technologies look relatively attractive due to recent developments in the materials and prototypes being manufactured.

  19. Intra-molecular refrigeration in enzymes

    E-print Network

    Hans J. Briegel; Sandu Popescu

    2009-12-14

    We present a simple mechanism for intra-molecular refrigeration, where parts of a molecule are actively cooled below the environmental temperature. We discuss the potential role and applications of such a mechanism in biology, in particular in enzymatic reactions.

  20. Elastic Metal Alloy Refrigerants: Thermoelastic Cooling

    SciTech Connect

    2010-10-01

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

  1. Enclosure for thermoelectric refrigerator and method

    NASA Technical Reports Server (NTRS)

    Park, Brian V. (Inventor); McGrath, Ralph D. (Inventor)

    1997-01-01

    An enclosed structure is provided for use with a refrigerator having a door assembly. The enclosed structure preferably contains superinsulation materials and a plurality of matching drawers. The enclosed structure preferably includes corner joints which minimize thermal energy transfer between adjacent superinsulation panels. The refrigerator may include a cooling system having a thermoelectric device for maintaining the temperature within the refrigerator at selected values. If desired, a fluid cooling system and an active gasket may also be provided between the door assembly and the enclosed structure. The fluid cooling system preferably includes a second thermoelectric device to maintain the temperature of fluid flowing through the active gasket at a selected value. The drawers associated with the refrigerator may be used for gathering, processing, shipping and storing food or other perishable items.

  2. Improving Industrial Refrigeration System Efficiency - Actual Applications 

    E-print Network

    White, T. L.

    1980-01-01

    REFRIGERATION SYSTEM EFFICIENCY ACTUAL APPLICATIONS Thomas L. White Energy .systems Design Section Monsanto Co.- St. Louis, Missouri ABSTRACT This paper discusses actual design and modifications for increased system efficiency and includes reduced...

  3. Energy use of icemaking in domestic refrigerators

    SciTech Connect

    Meier, A.; Martinez, M.S.

    1996-02-01

    This study was designed to develop and test a procedure to measure the electrical consumption of ice making in domestic refrigerators. The Department of Energy (DOE) test procedure was modified to include the energy used for icemaking in conventional refrigerators and those equipped with automatic icemakers. The procedure assumed that 500 grams of ice would be produced daily. Using the new test procedure and the existing DOE test (as a benchmark), four refrigerators equipped with automatic icemakers were tested for ice-making energy use. With the revised test, gross electricity consumption increased about 10% (100 kWh/yr) due to automatic icemaking but about 5% (55 kWh/yr) could be attributed to the special features of the automatic icemaker. The test also confirmed the feasibility of establishing procedures for measuring energy use of specific loads and other activities related to domestic refrigerators. Field testing and subsequent retesting revealed a 14% increase in energy use.

  4. Advances in refrigeration and heat transfer engineering

    SciTech Connect

    Bansal, Pradeep; Cremaschi, Prof. Lorenzo

    2015-01-01

    This special edition of Science and Technology for the Built Environment (STBE) presents selected high quality papers that were presented at the 15th International Refrigeration and Air Conditioning Conference held at Purdue University during July 14-17 2014. All papers went through the additional review before being finally accepted for publication in this special issue of Science and Technology and the Built Environment. Altogether 20 papers made to this special issue that cover a wide range of topics, including advancements in alternative refrigerants, heat exchangers/heat transfer, nano-fluids, systems design and optimization and modeling approaches. Although CO2 may perhaps have been the most researched and popular refrigerant in the past decade, R32 is being seriously considered lately as an alternative and environmentally friendly refrigerant for small systems due to its low Global Warming Potential (GWP).

  5. Exergetic sustainability evaluation of irreversible Carnot refrigerator

    NASA Astrophysics Data System (ADS)

    Aç?kkalp, Emin

    2015-10-01

    Purpose of this paper is to assess irreversible refrigeration cycle by using exergetic sustainability index. In literature, there is no application of exergetic sustainability index for the refrigerators and, indeed, this index has not been derived for refrigerators. In this study, exergetic sustainability indicator is presented for the refrigeration cycle and its relationships with other thermodynamics parameters including COP, exergy efficiency, cooling load, exergy destruction, ecological function and work input are investigated. Calculations are conducted for endoreversible and reversible cycles and then results obtained from the ecological function are compared. It is found that exergy efficiency, exergetic sustainable index reduce 47.595% and 59.689% and rising at the COP is 99.888% is obtained for endoreversible cycle. Similarly, exergy efficiency and exergetic sustainability index reduce 90.163% and 93.711% and rising of the COP is equal to 99.362%.

  6. Defrost Temperature Termination in Supermarket Refrigeration Systems

    SciTech Connect

    Fricke, Brian A; Sharma, Vishaldeep

    2011-11-01

    The objective of this project was to determine the potential energy savings associated with implementing demand defrost strategies to defrost supermarket refrigerated display case evaporators, as compared to the widely accepted current practice of controlling display case defrost cycles with a preset timer. The defrost heater energy use of several representative display case types was evaluated. In addition, demand defrost strategies for refrigerated display cases as well as those used in residential refrigerator/freezers were evaluated. Furthermore, it is anticipated that future work will include identifying a preferred defrost strategy, with input from Retail Energy Alliance members. Based on this strategy, a demand defrost system will be designed which is suitable for supermarket refrigerated display cases. Limited field testing of the preferred defrost strategy will be performed in a supermarket environment.

  7. Three-terminal quantum-dot refrigerators

    NASA Astrophysics Data System (ADS)

    Zhang, Yanchao; Lin, Guoxing; Chen, Jincan

    2015-05-01

    Based on two capacitively coupled quantum dots in the Coulomb-blockade regime, a model of three-terminal quantum-dot refrigerators is proposed. With the help of the master equation, the transport properties of steady-state charge current and energy flow between two quantum dots and thermal reservoirs are revealed. It is expounded that such a structure can be used to construct a refrigerator by controlling the voltage bias and temperature ratio. The thermodynamic performance characteristics of the refrigerator are analyzed, including the cooling power, coefficient of performance (COP), maximum cooling power, and maximum COP. Moreover, the optimal regions of main performance parameters are determined. The influence of dissipative tunnel processes on the optimal performance is discussed in detail. Finally, the performance characteristics of the refrigerators operated in two different cases are compared.

  8. Thermal modeling for an optical refrigerator

    NASA Astrophysics Data System (ADS)

    Martin, K. W.; Schomacker, J.; Fraser, T.; Dodson, C.

    2015-03-01

    Optical refrigeration is currently the only completely solid state cooling method capable of reaching cryogenic temperatures from room temperature. Optical cooling utilizing Yb:YLF as the refrigerant crystal has resulted in temperatures lower than 123K measured via a fluorescence thermometry technique. However, to be useful as a refrigerator this cooling crystal must be attached to a sensor or other payload. The phenomenology behind laser cooling, known as anti-Stokes fluorescence, has a relatively low efficiency which makes the system level optimization and limitation of parasitic losses imperative. We propose a variety of potential designs for a final optical refrigerator, enclosure and thermal link; calculate conductive and radiative losses, and estimate direct fluorescence reabsorption. Our simulated designs show losses between 60 and 255 mW, depending on geometry and enclosure choice, with a lower bound as low as 23 mW.

  9. Refrigeration system having standing wave compressor

    DOEpatents

    Lucas, Timothy S. (Glen Allen, VA)

    1992-01-01

    A compression-evaporation refrigeration system, wherein gaseous compression of the refrigerant is provided by a standing wave compressor. The standing wave compressor is modified so as to provide a separate subcooling system for the refrigerant, so that efficiency losses due to flashing are reduced. Subcooling occurs when heat exchange is provided between the refrigerant and a heat pumping surface, which is exposed to the standing acoustic wave within the standing wave compressor. A variable capacity and variable discharge pressure for the standing wave compressor is provided. A control circuit simultaneously varies the capacity and discharge pressure in response to changing operating conditions, thereby maintaining the minimum discharge pressure needed for condensation to occur at any time. Thus, the power consumption of the standing wave compressor is reduced and system efficiency is improved.

  10. combined cold compressor ejector helium refrigerator

    SciTech Connect

    Brown, D. P.

    1985-10-22

    A refrigeration apparatus having an ejector operatively connected with a cold compressor to form a two-stage pumping system. This pumping system is used to lower the pressure, and thereby the temperature of a bath of boiling refrigerant (helium). The apparatus as thus arranged and operated has substantially improved operating efficiency when compared to other processes or arrangements for achieving a similar low pressure.

  11. Combined cold compressor/ejector helium refrigerator

    NASA Astrophysics Data System (ADS)

    Brown, D. P.

    1984-06-01

    A refrigeration apparatus having an ejector operatively connected with a cold compressor to form a two stage pumping system is described. This pumping system is used to lower the pressure, and thereby the temperature of a bath of boiling refrigerant (helium). The apparatus as thus arranged and operated has substantially improved operating efficiency when compared to other processes or arrangements for achieving a similar low pressure.

  12. Combined cold compressor/ejector helium refrigerator

    DOEpatents

    Brown, D.P.

    1984-06-05

    A refrigeration apparatus having an ejector operatively connected with a cold compressor to form a two-stage pumping system. This pumping system is used to lower the pressure, and thereby the temperature of a bath of boiling refrigerant (helium). The apparatus as thus arranged and operated has substantially improved operating efficiency when compared to other processes or arrangements for achieving a similar low pressure.

  13. Solar Refrigerator/Freezers For Vaccines

    NASA Technical Reports Server (NTRS)

    Ratajczak, Anthony F.

    1988-01-01

    Report presents results of field tests of solar-cell-powered refrigerator/freezers for vaccines. Covers following topics: explanation of project; descriptions of refrigerator/freezer systems; account of installation experiences; performance data for 22 systems for which field-test data reported; summary of operational reliability; comments of users of some systems tested; and recommendations for design and future use. Photovoltaic systems store vaccines in remote regions where powerlines unavailable.

  14. Magnetic refrigeration in space - Practical considerations

    NASA Technical Reports Server (NTRS)

    Kittel, P.

    1980-01-01

    Various schemes of using adiabatic demagnetization to provide refrigeration in the 10-1000 mK range are discussed with particular reference to the requirements for use in space. The methods considered are complete demagnetization, isothermal demagnetization, moving magnet demagnetization, and continuous refrigeration. The requirements that are important for use in space are low mass, low power dissipation, high mechanical rigidity, modular design, and ease of use.

  15. Design of Industrial Process Refrigeration Systems 

    E-print Network

    Witherell, W. D.

    1987-01-01

    of the remaining processes (i. e., dairy and air separation) had good potential but would be no better at demonstrating pinch technology principles. TABLE 2 REFRIGERATION SYSTEM APPLICATIONS OF PRIMARY INTERST Industry Applications of Primary Interst Food... REFRIGERATION PROCESSES Industry Process Food Da iry - Mi Ik/ Ice Cream "Beverages - Brewery Cryogenic Air Separation Plants Chemical Industry hTrnonia "Olefins "Selected for In-Depth Pinch Technology StUdy 33 ESL-IE-87-09-06 Proceedings from...

  16. Combined cold compressor/ejector helium refrigerator

    DOEpatents

    Brown, Donald P. (Southold, NY)

    1985-01-01

    A refrigeration apparatus having an ejector operatively connected with a cold compressor to form a two-stage pumping system. This pumping system is used to lower the pressure, and thereby the temperature of a bath of boiling refrigerant (helium). The apparatus as thus arranged and operated has substantially improved operating efficiency when compared to other processes or arrangements for achieving a similar low pressure.

  17. Retrofit cogeneration system increases refrigeration capacity

    SciTech Connect

    Amberger, R.F. ); DeFrees, J.A. )

    1993-04-01

    This article describes a retrofit cogeneration systems for increasing refrigeration capacity at a milk processing plant in Queens, New York. The natural gas/ammonia cogeneration and subcooling systems reduce CO[sub 2] emissions and provide cost and energy savings. The topics of the article include the innovative aspects, computer modeling for system analysis, analysis technique, system configuration, refrigeration loads, operations and maintenance, cost effectiveness and environmental benefits.

  18. Vaccine refrigeration technologies and power sources

    SciTech Connect

    Rovero, C.; Waddle, D.; Oak Ridge National Lab., TN )

    1989-10-01

    Adequate refrigeration of vaccines is an essential component of the worldwide child immunization effort sponsored cooperatively by such development assistance agencies as the World Health Organization, the United Nations Children's Fund, and the US Agency for International Development (AID), and by developing countries. Unfortunately, the areas in most urgent need of effective immunization programs are often far from reliable refrigerated storage facilities or energy services. Selection of an appropriate energy supply and/or refrigeration technology has been seen as a limiting factor in effective immunization programs. In response to this problem, this document has been prepared to assist in the selection of reliable and affordable refrigeration systems. It provides information on refrigeration technologies and energy sources currently employed in the vaccine cold chain and discusses possible responses to a variety of energy-related problems, including intermittent or unreliable electric service, and unreliable supply, unavailability, or poor quality of fuels for refrigerators in health centers not served by the electric power grid. 18 refs., 5 figs.

  19. Computer modeling of commercial refrigerated warehouse facilities

    SciTech Connect

    Nicoulin, C.V.; Jacobs, P.C.; Tory, S.

    1997-07-01

    The use of computer models to simulate the energy performance of large commercial refrigeration systems typically found in food processing facilities is an area of engineering practice that has seen little development to date. Current techniques employed in predicting energy consumption by such systems have focused on temperature bin methods of analysis. Existing simulation tools such as DOE2 are designed to model commercial buildings and grocery store refrigeration systems. The HVAC and Refrigeration system performance models in these simulations tools model equipment common to commercial buildings and groceries, and respond to energy-efficiency measures likely to be applied to these building types. The applicability of traditional building energy simulation tools to model refrigerated warehouse performance and analyze energy-saving options is limited. The paper will present the results of modeling work undertaken to evaluate energy savings resulting from incentives offered by a California utility to its Refrigerated Warehouse Program participants. The TRNSYS general-purpose transient simulation model was used to predict facility performance and estimate program savings. Custom TRNSYS components were developed to address modeling issues specific to refrigerated warehouse systems, including warehouse loading door infiltration calculations, an evaporator model, single-state and multi-stage compressor models, evaporative condenser models, and defrost energy requirements. The main focus of the paper will be on the modeling approach. The results from the computer simulations, along with overall program impact evaluation results, will also be presented.

  20. Energy Efficient Operation of Ammonia Refrigeration Systems

    SciTech Connect

    Mohammed, Abdul Qayyum; Wenning, Thomas J; Sever, Franc; Kissock, Professor Kelly

    2013-01-01

    Ammonia refrigeration systems typically offer many energy efficiency opportunities because of their size and complexity. This paper develops a model for simulating single-stage ammonia refrigeration systems, describes common energy saving opportunities, and uses the model to quantify those opportunities. The simulation model uses data that are typically available during site visits to ammonia refrigeration plants and can be calibrated to actual consumption and performance data if available. Annual electricity consumption for a base-case ammonia refrigeration system is simulated. The model is then used to quantify energy savings for six specific energy efficiency opportunities; reduce refrigeration load, increase suction pressure, employ dual suction, decrease minimum head pressure set-point, increase evaporative condenser capacity, and reclaim heat. Methods and considerations for achieving each saving opportunity are discussed. The model captures synergistic effects that result when more than one component or parameter is changed. This methodology represents an effective method to model and quantify common energy saving opportunities in ammonia refrigeration systems. The results indicate the range of savings that might be expected from common energy efficiency opportunities.

  1. Study of mixed refrigerant undergoing pulsating flow in micro coolers with pre-cooling

    NASA Astrophysics Data System (ADS)

    Lewis, Ryan; Wang, Yunda; Schneider, Hayley; Lee, Y. C.; Radebaugh, Ray

    2013-10-01

    Micro cryogenic coolers can provide low temperatures with a smaller volumetric footprint and smaller power draw than their conventional-scale counterparts. However, they can exhibit lower-than-desired cooling power. We measure the specific cooling power of a refrigerant expanding from a high pressure of 0.6 MPa to a low pressure of 0.1 MPa, while undergoing pulsating flow in a micro cryogenic cooler with pre-cooling. We further observe that the pulses in the flow-rate occur due to a volume of liquid forming in the high-pressure coupling mini-channel. The composition of the flowing refrigerant is analyzed with gas chromatography and thermal conductivity detection (GC/TCD), showing that there is no overall composition change in the refrigerant after it enters the pre-cooling lines. A model of the cooling power under such a pulsating flow regime is developed with good agreement to measured values. An improved refrigerant mixture is designed with this model, and subsequently tested, showing increased specific cooling power.

  2. Boiling heat transfer of refrigerant R-113 in a small-diameter, horizontal tube

    SciTech Connect

    Wambsganss, M.W.; Jendrzejczyk, J.A.; Tran, T.N.; France, D.M.

    1992-01-01

    Results of a study of boiling heat transfer from refrigerant R-113 in a small-diameter (2.92-mm) tube are reported. Local heat transfer coefficients over a range of heat fluxes, mass fluxes, and equilibrium mass qualities were measured. The measured coefficients were used to evaluate eight different heat transfer correlations, some of which have been developed specifically for refrigerants. High heat fluxes and low flow rates are inherent in small channels, and this combination results in high boiling numbers. The high boiling number of the collected data shows that the nucleation mechanism was dominant. As a result, the two-phase correlations that predicted this dominance also predicted the data best if they also properly modeled the physical parameters. The correlations of Lazarek and Black and of Shah, as modified in this study, predicted the data very well. It is also shown that a simple form, suggested by Stephan and Abdelsalam for nucleate boiling, correlates the data equally well. This study is part of a research program in multiphase flow and heat transfer, with the overall objective of developing validated design correlations and predictive methods that will facilitate the design and optimization of compact heat exchangers for use with environmentally acceptable alternatives for chlorofluorocarbon (CFC) refrigerants and refrigerant mixtures.

  3. Efficient electrochemical refrigeration power plant using natural gas with ?100% CO2 capture

    NASA Astrophysics Data System (ADS)

    Al-musleh, Easa I.; Mallapragada, Dharik S.; Agrawal, Rakesh

    2015-01-01

    We propose an efficient Natural Gas (NG) based Solid Oxide Fuel Cell (SOFC) power plant equipped with ?100% CO2 capture. The power plant uses a unique refrigeration based process to capture and liquefy CO2 from the SOFC exhaust. The capture of CO2 is carried out via condensation and purification using two rectifying columns operating at different pressures. The uncondensed gas mixture, comprising of relatively high purity unconverted fuel, is recycled to the SOFC and found to boost the power generation of the SOFC by 22%, when compared to a stand alone SOFC. If Liquefied Natural Gas (LNG) is available at the plant gate, then the refrigeration available from its evaporation is used for CO2 Capture and Liquefaction (CO2CL). If NG is utilized, then a Mixed Refrigerant (MR) vapor compression cycle is utilized for CO2CL. Alternatively, the necessary refrigeration can be supplied by evaporating the captured liquid CO2 at a lower pressure, which is then compressed to supercritical pressures for pipeline transportation. From rigorous simulations, the power generation efficiency of the proposed processes is found to be 70-76% based on lower heating value (LHV). The benefit of the proposed processes is evident when the efficiency of 73% for a conventional SOFC-Gas turbine power plant without CO2 capture is compared with an equivalent efficiency of 71.2% for the proposed process with CO2CL.

  4. The Oak Ridge Refrigerant Management Program

    NASA Technical Reports Server (NTRS)

    Kevil, Thomas H.

    1995-01-01

    For many years, chlorofluorocarbons (CFC's) have been used by the Department of Energy's (DOE) Oak Ridge Y-12 Plant in air conditioning and process refrigeration systems. However, Title 6 of the Clean Air Act Amendments (CAAA) and Executive Order 12843 (Procurement Requirements and Policies for Federal Agencies for Ozone Depleting Substances) signed by President Clinton require, as policy, that all federal agencies maximize their use of safe, alternate refrigerants and minimize, where economically practical, the use of Class 1 refrigerants. Unfortunately, many government facilities and industrial plants have no plan or strategy in place to make this changeover, even though their air conditioning and process refrigeration equipment may not be sustainable after CFC production ends December 31, 1995. The Y-12 Plant in Oak Ridge, Tennessee, has taken an aggressive approach to complying with the CAAA and is working with private industry and other government agencies to solve tough manufacturing and application problems associated with CFC and hydrochlorofluorocarbon (HCFC) alternatives. Y-12 was the first DOE Defense Program (DP) facility to develop a long-range Stratospheric Ozone Protection Plan for refrigerant management for compliance with the CAAA. It was also the first DOE DP facility to complete detailed engineering studies on retrofitting and replacing all air conditioning and process refrigeration equipment to enable operation with alternate refrigerants. The management plan and engineering studies are models for use by other government agencies, manufacturing plants, and private industry. This presentation identifies some of the hidden pitfalls to be encountered in the accelerated phaseout schedule of CFC's and explains how to overcome and prevent these problems. In addition, it outlines the general issues that must be considered when addressing the phase-out of ozone depleting substances and gives some 'lessons learned' by Y-12 from its Refrigerant Management Program. Discussion topics include requirements for developing a refrigerant management plan and establishing priorities for cost-effective compliance with the CAAA, as well as ways in which employees can be empowered to develop a comprehensive refrigerant management plan. The result of this employee empowerment was a cooperative labor-management effort that is beneficial for Y-12, DOE, and the environment.

  5. SIMULATION RESULTS OF SINGLE REFRIGERANTS FOR USE IN A DUAL-CIRCUIT REFRIGERATOR/FREEZER

    EPA Science Inventory

    The paper reviews the refrigerant/freezer (RF) design and refrigerant selection process that is necessary to design an energy efficient RF that does not use fully halogenated chlorofluorocarbons (CFCs). EPA is interested in phasing out CFCs in RFs to minimize stratospheric ozone ...

  6. 10 CFR 429.42 - Commercial refrigerators, freezers, and refrigerator-freezers.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Commercial refrigerators, freezers, and refrigerator-freezers. 429.42 Section 429.42 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION CERTIFICATION, COMPLIANCE... maximum daily energy consumption or other measure of energy consumption of a basic model for...

  7. A Superfluid Pulse Tube Refrigerator Without Moving Parts for Sub-Kelvin Cooling

    NASA Technical Reports Server (NTRS)

    Miller, Franklin K.

    2012-01-01

    A report describes a pulse tube refrigerator that uses a mixture of He-3 and superfluid He-4 to cool to temperatures below 300 mK, while rejecting heat at temperatures up to 1.7 K. The refrigerator is driven by a novel thermodynamically reversible pump that is capable of pumping the He-3 He-4 mixture without the need for moving parts. The refrigerator consists of a reversible thermal magnetic pump module, two warm heat exchangers, a recuperative heat exchanger, two cold heat exchangers, two pulse tubes, and an orifice. It is two superfluid pulse tubes that run 180 out of phase. All components of this machine except the reversible thermal pump have been demonstrated at least as proof-of-concept physical models in previous superfluid Stirling cycle machines. The pump consists of two canisters packed with pieces of gadolinium gallium garnet (GGG). The canisters are connected by a superleak (a porous piece of VYCOR glass). A superconducting magnetic coil surrounds each of the canisters.

  8. CFSs AND HCFCs -- Refrigerant relatives

    SciTech Connect

    Wray, T.K.

    1993-06-01

    CFCs and halons, another type of refrigerant, have been implicated as a primary cause in depletion of the stratospheric ozone, which protects the Earth from harmful ultraviolet radiation. The United Nations Environment Program and 22 countries in 1987 created the Montreal Protocol on Substances That Deplete the Ozone Layer to phase out use of ozone-depleting compounds (DCs), particularly CFCs. More than 70 countries representing 90% of the world's use of these compounds participate in the treaty. The original agreement called for a freeze at 1986 levels in the production and consumption of certain CFCs (11, 12, 113, 114 and 115), and Halon 1211, 1301 and 2402, as well as a CFC reduction to 50% of 1986 levels by 1998. In response to scientific evidence of increase stratospheric ozone depletion, however, the participating countries amended the Montreal protocol. The most recent changes occurred in late 1992, requiring reductions in CFC production to 75% of 1986 levels by Jan. 1, 1994, and a phaseout by Jan. 1, 1996.

  9. Conversions to non-CFC refrigerants simple, inexpensive

    SciTech Connect

    Corbett, R.A.

    1995-05-29

    The US Environmental Protection Agency (EPA) regulations that ban the production of chlorofluorocarbon (CFC) refrigerants after Dec. 31, 1995, are prompting refinery and petrochemical plant operators to convert existing refrigeration systems to operation on non-CFC refrigerants. A recently completed conversion study of three typical process refrigeration systems installed in a major petrochemical complex on the US Gulf Coast, typifies the analyses and procedures required to successfully convert a system to non-CFC operation. The study also provides insight into some potential refrigerant alternatives that are effective replacements for CFCs. Also highlighted are recommendations and limitations for conversion of some common types of refrigeration systems used in refining and petrochemical processing.

  10. 75 FR 59469 - Energy Conservation Program: Energy Conservation Standards for Residential Refrigerators...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-27

    ...-Size Freezers 3. Compact Refrigeration Products 4. Built-In Refrigeration Products 5. Summary of... document as ``refrigeration products''), shall be designed to ``achieve the maximum improvement in energy... this notice, DOE proposes amended energy conservation standards for refrigeration products....

  11. LOW-GLOBAL-WARMING CHEMICALS AND REFRIGERANT TECHNOLOGIES (ATMOSPHERIC PROTECTION BRANCH, APPCD, NRMRL)

    EPA Science Inventory

    The Atmospheric Protection Branch's Refrigeration Applications Laboratory has the capability to test several types of refrigeration equipment with various refrigerants. Refrigeration compressors are tested according to the ANSI/ASHRAE 23-1993 Test Standard and under various oper...

  12. A thermoacoustically driven pulse tube refrigerator capable of working below 120 K

    NASA Astrophysics Data System (ADS)

    Jin, T.; Chen, G. B.; Shen, Y.

    2001-08-01

    Based on the discussion of the matching problems between the prime mover and pulse tube, a self-made standing-wave thermoacoustic prime mover is used to drive a coaxial single-stage pulse tube refrigerator. A lowest refrigeration temperature of 138 K was obtained from the preliminary tests in 1999. Then, some improvements have been made to the heat exchangers and the connection between prime mover and pulse tube. The minimum cooling temperatures of 119.7 and 117.6 K have been obtained from the recent experiments with helium and helium-argon mixture filling of 2.0 MPa as the working fluids, respectively. It is a great progress for the standing-wave machine and provides the possibility of liquefying natural gas of 0.2 MPa.

  13. Reduction of chlorofluorocarbon emissions from refrigeration systems

    SciTech Connect

    Cordova, A.; Kennicott, M.A.

    1992-01-01

    Recently enacted State and Federal legislation, (The Clean Air Act and Colorado Senate Bill 77), and the implementation of regulations for each, forbid the intentional release of ozone depleting chlorofluorocarbons(CFCs) from refrigeration and air conditioning systems to the atmosphere. In addition, an international agreement (The Montreal Protocol), calls for CFC manufacturing reductions, which began in 1991, and eventual discontinuation. The declining supply and resultant escalating costs of CFCs are additional driving forces toward conservation and reuse of present refrigerant resources. Rocky Flats Plant (RFP) currently has an estimated 42,000 pounds of CFCs in refrigeration and air conditioning systems. The purpose of this paper is to discuss steps being taken at RFP toward the abatement of CFC releases. The main thrust of our efforts is the use of a refrigerant management system, used to recover and recycle our current CFC stock. Additional methods of further reducing CFC emissions will also be discussed. These include the installation of state-of-the-art oil filtration systems on major chiller units, installation of spring-loaded pressure relief valves and the retrofitting of major chiller units to accept less harmful, alternative refrigerants.

  14. Reduction of chlorofluorocarbon emissions from refrigeration systems

    SciTech Connect

    Cordova, A.; Kennicott, M.A.

    1992-09-01

    Recently enacted State and Federal legislation, (The Clean Air Act and Colorado Senate Bill 77), and the implementation of regulations for each, forbid the intentional release of ozone depleting chlorofluorocarbons(CFCs) from refrigeration and air conditioning systems to the atmosphere. In addition, an international agreement (The Montreal Protocol), calls for CFC manufacturing reductions, which began in 1991, and eventual discontinuation. The declining supply and resultant escalating costs of CFCs are additional driving forces toward conservation and reuse of present refrigerant resources. Rocky Flats Plant (RFP) currently has an estimated 42,000 pounds of CFCs in refrigeration and air conditioning systems. The purpose of this paper is to discuss steps being taken at RFP toward the abatement of CFC releases. The main thrust of our efforts is the use of a refrigerant management system, used to recover and recycle our current CFC stock. Additional methods of further reducing CFC emissions will also be discussed. These include the installation of state-of-the-art oil filtration systems on major chiller units, installation of spring-loaded pressure relief valves and the retrofitting of major chiller units to accept less harmful, alternative refrigerants.

  15. Cold chain: solar refrigerator field tested.

    PubMed

    1983-04-01

    The Health Ministries of Colombia and Peru, in collaboration with the Expanded Program on Immunization (EPI)/Pan American Health Organization (PAHO) and the Centers for Disease Control (CDC), have begun field testing a solar-powered vaccine refrigerator. The aim of the fields trials is to determine whether solar refrigerators can maintain the temperatures required for vaccine storage (+4-8 degrees Celsius) and produce ice at a rate of 2 kg/24 hours under different environmental conditions. these refrigerators would be particularly useful in areas that lack a consistent supply of good quality fuel or where the electrical supply is intermittent or nonexistent. Full appraisal of this technology will require 2 years of field testing; Colombia and Peru expect to complete testing in 1985. To date, 5 models have passed CDC-developed specifications, all of which are manufactured in the US. PAHO/WHO recommends that health ministries should consider the following guidelines in considering the purchase of a particular system: the initial purchase should be for a limited quantity (about 5) of refrigerators to permit field testing; solar panels should meet specific criteria; consideration should be given only to those models that have passed qualification tests; each unit should be fully equipped with monitoring devices and spare parts; and a trained refrigerator technician should be available to repair the equipment. PMID:12314506

  16. Potential Refrigerants for Power Electronics Cooling

    SciTech Connect

    Starke, M.R.

    2005-10-24

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

  17. Pressure-enthalpy diagrams for alternative refrigerants

    SciTech Connect

    Chen, J.; Kruse, H.

    1996-10-01

    Thermodynamic diagrams, particularly log(p)-h diagrams, have become very convenient tools for refrigeration and air-conditioning industries. To promote alternative refrigerants-related development and application, it is urgently required to provide the industries with reliable engineering diagrams for the most promising candidate refrigerants. A computer program has been developed for automatically producing log(p)-h diagrams for alternative refrigerants. The Lee Kesler Ploecker (LKP) equation of state has been used to calculate thermodynamic data. Some modifications have been made to the LKP to improve the calculation convergency. In this paper three sample diagrams for R134a, a binary R410A and a ternary R407B which have been enclosed and analyzed. To investigate the LKP calculation accuracy details, an extensive deviation analysis has been made for R134a. For mixed refrigerants, good calculation accuracy was achieved by optimizing the binary interactive parameters. The system can produce log(p)-h diagrams with reliable accuracy, high quality, and flexibility to meet any size and color requirements.

  18. An analytical screening of alternatives for R-502 in low-temperature refrigerating applications

    SciTech Connect

    Fischer, S.K.

    1992-01-01

    R-502 is used as the working fluid of low-temperature refrigerating systems with evaporating temperatures as low as {minus}40{degrees}F ({minus}40{degrees}C). It was selected as the refrigerant of choice for these applications because it is both nonflammable and nontoxic and has an acceptable compressor discharge temperature when used in a high-efficiency vapor-compression system. Replacement fluids are going to be needed for use in place of R-502, however, because of the provisions of the Montreal Protocol. R-502 is an azeotropic blend of R-22 and R-115, and R-115 is a chlorofluorocarbon (CFC) that is contributing to the destruction of stratospheric ozone. The provisions of the Montreal Protocol currently require a total phase-out of the production of all fully halogenated CFCs, including R-115, by the year 2000. Consequently, replacement fluids will be needed for new and existing equipment. This study was initiated to identify other possible fluids that can be used either in new or retrofit applications for low-temperature refrigerant. It includes an evaluation of predicted cycle efficiency, system capacity, pressure ratio, fluid flammability, and compressor discharge temperature. Eight different chemical compounds are considered for use as pure refrigerants as well as components in binary and ternary mixtures: R-134a, R-134, R-125, R-143a, R-152a,R-32, R-124, and R-22. An exhaustive study of the composition of blends was performed to determine the mass fractions of each component in the mixtures that are most promising on the basis of efficiency, flammability, low discharge temperature, and acceptable capacity and pressure ratio. Several blends are identified for further laboratory and analytical evaluation.

  19. An analytical screening of alternatives for R-502 in low-temperature refrigerating applications

    SciTech Connect

    Fischer, S.K.

    1992-08-01

    R-502 is used as the working fluid of low-temperature refrigerating systems with evaporating temperatures as low as {minus}40{degrees}F ({minus}40{degrees}C). It was selected as the refrigerant of choice for these applications because it is both nonflammable and nontoxic and has an acceptable compressor discharge temperature when used in a high-efficiency vapor-compression system. Replacement fluids are going to be needed for use in place of R-502, however, because of the provisions of the Montreal Protocol. R-502 is an azeotropic blend of R-22 and R-115, and R-115 is a chlorofluorocarbon (CFC) that is contributing to the destruction of stratospheric ozone. The provisions of the Montreal Protocol currently require a total phase-out of the production of all fully halogenated CFCs, including R-115, by the year 2000. Consequently, replacement fluids will be needed for new and existing equipment. This study was initiated to identify other possible fluids that can be used either in new or retrofit applications for low-temperature refrigerant. It includes an evaluation of predicted cycle efficiency, system capacity, pressure ratio, fluid flammability, and compressor discharge temperature. Eight different chemical compounds are considered for use as pure refrigerants as well as components in binary and ternary mixtures: R-134a, R-134, R-125, R-143a, R-152a,R-32, R-124, and R-22. An exhaustive study of the composition of blends was performed to determine the mass fractions of each component in the mixtures that are most promising on the basis of efficiency, flammability, low discharge temperature, and acceptable capacity and pressure ratio. Several blends are identified for further laboratory and analytical evaluation.

  20. 46 CFR 58.20-20 - Refrigeration piping.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS Refrigeration...primary refrigerant, brine, or fluid used, and shall be of such chemical and physical properties as to remain ductile at the...