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Compressor Calorimeter Test of R-404A Alternatives ARM-31a, D2Y-65, L-40, and R32 + R-134a Mixture using a Scroll Compressor

Description: As a contribution to the AHRI Low-GWP Alternative Refrigerants Evaluation Program (AREP), this study compares the performance of four lower-GWP alternative refrigerants, ARM-31a, D2Y-65, L-40, and R-32 + R-134a mixture, to that of refrigerant R-404A (baseline) in a scroll compressor designed for medium temperature refrigeration applications. These comparisons were carried out via compressor calorimeter tests performed on a compressor designed for refrigerant R-404A and having a nominal rated capacity of 23,500 Btu/hr. Tests were conducted over a suction dew point temperature range of -10 F to 35 F in 5 F increments and a discharge dew point temperature range of 70 F to 140 F in 10 F increments. All the tests were performed with 20 F superheat, 40 F superheat, and 65 F suction temperature. A liquid subcooling level of 10 F to 15 F was maintained for all the test conditions. However, the cooling capacities reported in this study are normalized for 0 F subcooling. The tests showed that the compressor energy efficiency ratio (EER) and cooling capacity with all four alternative refrigerants tested are higher at higher saturation suction and saturation discharge temperature and lower at lower saturation suction and saturation discharge temperature, compared to that of R-404A. Discharge temperatures of all the alternative refrigerants were higher than that of R-404A at all test conditions.
Date: August 1, 2013
Creator: Shrestha, Som S; Sharma, Vishaldeep & Abdelaziz, Omar
Partner: UNT Libraries Government Documents Department

Accelerated screening methods for determining chemical and thermal stability of refrigerant-lubricant mixtures, Part II: Experimental comparison and verification of methods. Volume 2, In situ conductivity data

Description: Data are presented for the accelerated screening methods for determining chemical and thermal stability of refrigerant-lubricant mixtures.
Date: September 1, 1995
Creator: Kauffman, R.
Partner: UNT Libraries Government Documents Department

Boiling Heat Transfer with Three Fluids in Small Circular and Rectangular Channels

Description: Small circular and noncircular channels are representative of flow passages act evaporators and condensers. This report describes results of an experimental study on heat transfer to the flow boiling of refrigerants (R-12) and refrigerant-134a (R-134a) in a small horizontal circular-cross-section tube. The tube diameter of 2.46 mm was chosen to approximate the hydraulic diameter of a 4.06 x 1.70 mm rectangular channel previously studied with R-12, and a 2.92-mm-diameter circular tube previously studied with R-113. The objective of this study was to assess the effects of channel geometry and fluid properties on the heat transfer coefficient and to obtain additional insights relative to the heat transfer mechanism(s). The current circular flow channel for the R-12 and R-134a tests was made of brass and had an overall length of 0.9 in. The channel wall was electrically heated, and thermocouples were installed on the channel wall and in the bulk fluid stream. Voltage taps were located at the same axial locations as the stream thermocouples to allow testing over an exit quality range to 0.94 and a large range of mass flux (58 to 832 kg/m sq s) and heat flux (3.6 to 59 kW/m sq). Saturation pressure was nearly constant, averaging 0.82 MPa for most of the testing, with some tests performed at a lower pressure of 0.4--0.5 MPa. Local heat transfer coefficients were determined experimentally as a function of quality along the length of the test section. Analysis of all data for three tubes and three fluids supported the conclusion that a nucleation mechanism dominates for flow boiling in small channels. Nevertheless, a convection-dominant region was obtained experimentally in this study at very low values of wall superheat (<(approx) 2.75C). The circular and rectangular tube data for three fluids were successfully correlated in the nucleation-dominant region.
Date: January 1995
Creator: Tran, T. N.; Wambsganss, M. W. & France, D. M.
Partner: UNT Libraries Government Documents Department

Compressor Calorimeter Test of R-410A Alternatives R-32, DR-5, and L-41a

Description: As a contribution to the AHRI Low-GWP Alternative Refrigerants Evaluation Program (AREP), this study compares performance of alternative refrigerants R32, DR-5, and L-41A to that of refrigerant R-410A (baseline) in a scroll compressor designed for air-conditioning and heat pump applications. Compressor calorimeter tests were performed to evaluate the performance of the lower-GWP alternative refrigerants in place of the common refrigerant R-410A in a 36,000 Btu/hr compressor calorimeter using a compressor having a nominal rated capacity of 21,300 Btu/hr. Tests were conducted over a suction dew point temperature range of 10 F to 55 F in 5 F increments and a discharge dew point temperature range of 70 F to 140 F in 10 F increments. All the tests were performed with 20 F superheat, 40 F superheat and 65 F suction temperature. A liquid subcooling level of 15 F was maintained for all the test conditions. The tests showed that performance of these three lower-GWP alternative refrigerants is comparable to that of R-410A. For the 20 F superheat and 15 F subcooling test conditions, EERs of R32, DR-5, and L-41A were 90% to 99%, 96% to 99%, and 94% to 101%, respectively, compared to that of R-410A. Similarly, cooling capacities of R32, DR-5, and L-41A were 98% to 103%, 92% to 96%, and 84% to 92%, respectively, compared to that of R-410A.
Date: February 1, 2013
Creator: Shrestha, Som S; Mahderekal, Isaac; Sharma, Vishaldeep & Abdelaziz, Omar
Partner: UNT Libraries Government Documents Department

Experimental Investigation of Direct Freeze Separation Process Using Refrigerant R-C318 (Octafluorocyclobutane)

Description: Report concerning the possible use of octafluorocyclobutane, R-C318, being used in the direct freezing process as a means of extracting fresh water from sea water. Topics include using R-C318 to make ice, flash precooling, design of a small direct freezing pilot plant using R-C318, and related economic studies.
Date: April 1967
Creator: Johnson, C. A.; Moore, S. J.; Wagaman, N. D. & Sandell, D. J.
Partner: UNT Libraries Government Documents Department

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

Description: 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.
Date: March 15, 1999
Creator: Chen, D.T. & Conklin, J.C.
Partner: UNT Libraries Government Documents Department

Comparison of Analytical and Experimental Effectiveness of Four-Row Plate-Fin-Tube Heat Exchangers with Water, R-22, and R-410A

Description: The analytical solutions of heat exchanger effectiveness for four-row crcmilow, cross-countertlow and cross-paralleltlow have been derived in the recent study. The main objective of this study is to investigate the etlkct of heat exchawger tlow conllguration on thermal performance with refrigerant mixtures. Difference of heat exchanger effectiveness for all flow arrangements relative to an analytical many-row solution has been analyzed. A comparison of four-row cross cou~ltet-ilow heat exchanger effectiveness between analytical solutions and experimental data with water, R-22, and R-4 10A is presented.
Date: November 15, 1998
Creator: Baxter, V.D.; Chen, T.D. & Conklin, J.C.
Partner: UNT Libraries Government Documents Department

Boiling Heat Transfer of Refrigerant R-113 in a Small-Diameter, Horizontal Tube

Description: 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.
Date: January 1992
Creator: Wambsganss, M. W.; France, D. M.; Jendrzejczyk, J. A. & Tran, T. N.
Partner: UNT Libraries Government Documents Department

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

Description: 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.
Date: March 31, 1995
Creator: Womeldorf, C.; King, M. & Grosshandler, W.
Partner: UNT Libraries Government Documents Department

EHD enhancement of boiling/condensation, heat transfer of alternate refrigerants. Final Report for 1993-1999

Description: The goal was to address the feasibility of frost control by the EHD technique for operating conditions and geometries of significance to refrigeration. The objective of the experimental investigation was to demonstrate by experiment the feasibility of the EHD technique for control of frost on a cold surface under operating conditions of direct significance to refrigeration applications.
Date: September 1, 1999
Creator: Ohadi, M. M.
Partner: UNT Libraries Government Documents Department

Carbon Dioxide and Ionic Liquid Refrigerants

Description: Advanced Research Projects Agency-Energy project sheet summarizing general information about the Building Energy Efficiency Through Innovative Thermodevices (BEETIT) program including critical needs, innovation and advantages, impacts, and contact information. This sheet discusses air conditioning that uses new refrigerants as part of the "Compact, Efficient Air Conditioning with Ionic Liquid-Based Refrigerants" project.
Date: February 15, 2012
Creator: University of Notre Dame
Partner: UNT Libraries Government Documents Department

High-Efficiency Stirling Air Conditioning

Description: Advanced Research Projects Agency-Energy project sheet summarizing general information about the Building Energy Efficiency Through Innovative Thermodevices (BEETIT) program including critical needs, innovation and advantages, impacts, and contact information. This sheet discusses air conditioning that would use no polluting refrigerants as part of the "Stirling Air Conditioner for Compact Cooling" project.
Date: February 15, 2012
Creator: Infinia Corporation
Partner: UNT Libraries Government Documents Department

Materials Compatibility and Lubricants Research on CFC-refrigerant substitutes; Quarterly MCLR program technical progress report, 1 October 1993--31 December 1993

Description: The Materials Compatibility and Lubricants Research (MCLR) program supports critical research to accelerate the introduction of CFC and HCFC refrigerant substitutes. The MCLR program addresses refrigerant and lubricant properties and materials compatibility. The primary elements of the work include data collection and dissemination, materials compatibility testing, and methods development. The work is guided by an Advisory Committee consisting of technical experts from the refrigeration and air-conditioning industry and government agencies. The AirConditioning and Refrigeration Technology Institute, Inc., (ARTI) manages and contracts multiple research projects and a data collection and dissemination effort. Detailed results from these projects are reported in technical reports prepared by each subcontractor.
Date: January 1, 1994
Creator: Szymurski, S.R.; Hourahan, G.C. & Godwin, D.S.
Partner: UNT Libraries Government Documents Department

Recent development in green buildings

Description: Because of the environmental concerns about some materials used in buildings, particularly chlorofluorocarbon (CFC) fluids used as the blowing agent for insulation materials and as refrigerants used in the air conditioning systems have led to a search for environmentally safe alternatives. For insulation materials, new non-CFC blowing agents are still under development. However, the old insulation materials in the buildings will stay because they do not pose any further environmental damage. It is a different story for refrigerants used in air conditioning systems. This study reports that the change-over from CFC to non-CFC refrigerants in the existing and future air conditioning equipment could be a chance not only to take care of the environmental concerns, but to save energy as well. Alternative air conditioning technologies, such as the desiccant dehumidification and absorption systems, and the potential of some natural substances, such as carbon dioxide, as the future refrigerants are also discussed.
Date: December 31, 1996
Creator: Mei, V.C.
Partner: UNT Libraries Government Documents Department

Thermophysical properties of HCFC alternatives. Quarterly report, 1 April 1996--30 June 1996

Description: Numerous fluids and fluid mixtures have been identified as promising alternatives to the HCFC refrigerants, but, for many of them, reliable thermodynamic data do not exist. In particular, reliable thermodynamic properties data and models are needed to predict the performance of the new refrigerants in heating and cooling equipment and to design and optimize equipment to be reliable and energy efficient. The objective of this project is to measure, with high accuracy, selected thermodynamic properties data for two pure refrigerants and nine refrigerant blends; these data will be used to fit equations of state and other property models which can be used in equipment design. The new data will fill in gaps in the existing data and resolve problems and differences that exist in and between existing data sets. Most of the studied fluids and blends are potential replacements for HCFC-22 and/or R502; in addition, one pure fluid and one blend are potential replacements for CFC-13 in low temperature refrigeration applications.
Date: July 1, 1996
Creator: Haynes, W.M.
Partner: UNT Libraries Government Documents Department

Potentially useful polyolester lubricant additives an overview of antioxidants, antiwear and antiseize compounds

Description: Reliable service lubrication of compressors with polyolesters that do not contain additives is the optimal goal for hermetic compressor use. Chlorine derived from CFC and HCFC refrigerants is reported to have effective antiwear properties and negates the widespread use of additives in mineral oil lubricated systems. The use of antioxidants for mineral oil and polyolesters have been reported; antioxidant additive activity seems essential for polyolesters.- Antiwear and antiseize additives seem to be a short term goal for use with polyolesters. High silicone aluminum to steel wear seems to be a primary target for additive use. The interaction of specific heteroatom organic compounds with highly polar surface active synthetic polyolester lubricants is complex. Results of an extensive literature search describe results from a service base determined at ambient conditions. Known lubricant additives used in the hermetic compressor industry, the. mode of action of several types of additives and some lubricant additive chemistry that demonstrates selective thermal stability in conjunction with the chemical structure are examined.
Date: November 1, 1996
Creator: Cavestri, R.C.
Partner: UNT Libraries Government Documents Department

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

Description: 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.
Date: April 1, 1999
Creator: Gunsel, Selda & Pozebanchuk, Michael
Partner: UNT Libraries Government Documents Department

Engineering analysis of the use of compression refrigerants in the thin polymer icemaker. Revision 2/96

Description: Preliminary designs for systems which satisfy code requirements using R-134a and R-C318 as refrigerants are developed. Standard thermodynamic and heat transfer analysis were used to determine expected performance for the systems. The R-C318 has a somewhat peculiar vapor/liquid equilibrium curve, and a novel heat exchanger was introduced to optimize performance of this refrigerant. These performance assessments with component and assembly cost estimates were combined to prepare life-cycle costs for the two new systems. Compared to commercially available systems, these ``polymer evaporator`` systems seem to be completely feasible technically and if successfully demonstrated, they should have substantial economic advantages over existing ice-making devices.
Date: February 1, 1996
Creator: Leigh, R.W. & Andrews, J.W.
Partner: UNT Libraries Government Documents Department

Materials compatibility and lubricants research on CFC-refrigerant substitutes. Quarterly report, October 1, 1995--December 31, 1995

Description: The quarterly status report for the Materials Compatibility and Lubricants Research Program is presented. Objectives for 1 October 1995--31 December 1995 include completion of contract negotiations for Study of Foaming Characteristics project, and finalizing Phase IV and Phase V projects.
Date: February 1, 1996
Creator: Szymurski, S.R.
Partner: UNT Libraries Government Documents Department

ARTI refrigerant database

Description: 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.
Date: February 1, 1997
Creator: Calm, J.M.
Partner: UNT Libraries Government Documents Department

Investigation of flushing and clean-out methods for refrigeration equipment to ensure system compatibility

Description: SECTION 608 of the Clean Air Act Amendments has altered much of the refrigeration service contracting industry. MCLR Project Number 660-52502 was established to examine two areas where the Amendments are influencing contractors to determine if more cost-effective service procedures might be developed. One area where existing service procedures are being revisited involves the removal of contaminants from a refrigeration system after a motor burnout. At one time, a Class 1 substance such as CFC-11 or CFC-113 was used as a flushing agent for cleaning a system after a burnout. On large systems, the compressor was disassembled, and the parts were cleaned using 1,1,1-trichloroethane (TCA) or a TCA-containing mixture. Such alternatives are seldom possible today, as the manufacture of Class 1 substances was banned on January 1, 1996. This report describes processes for mineral oil removal, process alternatives for servicing burnouts, solvents, and laboratory retrofit tests.
Date: April 24, 1996
Creator: Byrne, J.J.; Shows, M. & Abel, M.W.
Partner: UNT Libraries Government Documents Department

Thermophysical properties of HCFC alternatives. Final report, 1 April 1994--31 October 1996

Description: Numerous fluids and fluid mixtures have been identified as promising alternatives to the HCFC refrigerants, but, for many of them, reliable thermodynamic data do not exist. In particular, reliable thermodynamic properties data and models are needed to predict the performance of the new refrigerants in heating and cooling equipment and to design and optimize equipment to be reliable and energy efficient. The objective of the project is to measure, with high accuracy, selected thermodynamic properties data for one pure refrigerant and nine refrigerant blends; these data will be used to fit equations of state and other property models which can be used in equipment design. The new data will fill in gaps in the existing data and resolve problems and differences that exist in and between existing data sets. Most of the studied fluids and blends are potential replacements for HCFC-22 and/or R-502; in addition, one pure fluid and one blend are potential replacements for CFC-13 in low temperature refrigerant applications.
Date: November 1, 1996
Creator: Haynes, W.M.
Partner: UNT Libraries Government Documents Department