Cycle performance comparison between a nonazeotropic refrigerant mixture and R22

Conference · Tue Jan 01 04:00:00 EST 1991

OSTI ID:5475352

Vineyard, E A; Conklin, J C

In an effort to improve the efficiency of residential heat pumps and reduce the ozone depletion potential (ODP) of the refrigerant, nonazeotropic mixtures (NARMs) are being investigated as part of the Building Equipment Research program at Oak Ridge National Laboratory (ORNL). One of the NARMs, a mixture consisting of approximately 75% R143a and 25% R124 (percentages by mass) was tested over a range of mass flow rates at Department of Energy (DOE) heat pump rating conditions (27.8 {degrees}C cooling). Since NARMs exhibit an inherent decrease in the heat transfer coefficient relative to pure refrigerants, three refrigerant-side enhancements were tested to determine if overall system performance could be improved. In addition to the performance of the NARM, performance for the tube surfaces with R22 was measured to determine any benefits from the nonisothermal phase-change process characteristic of NARMs. Comparisons were made on the basis of the coefficient of performance (COP) as a function of capacity. The conclusion was that refrigerant-side heat transfer enhancements improved the COP of the NARM-operated system more than that of the R22-operated system. 7 refs., 6 figs.

• Research Organization: Oak Ridge National Lab., TN (United States)
• Sponsoring Organization: DOE; USDOE, Washington, DC (United States)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 5475352
• Report Number(s): CONF-910803-2; ON: DE91017225
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
320106* -- Energy Conservation
Consumption
& Utilization-- Building Equipment-- (1987-)
36 MATERIALS SCIENCE
360603 -- Materials-- Properties
BINARY MIXTURES
COEFFICIENT OF PERFORMANCE
COMPARATIVE EVALUATIONS
DISPERSIONS
ENERGY TRANSFER
EVALUATION
FLUIDS
HEAT EXCHANGERS
HEAT PUMPS
HEAT TRANSFER
MIXTURES
REFRIGERANTS
RESIDENTIAL SECTOR
WORKING FLUIDS