Laboratory Testing of a Heat Pump System with Water-to-Water, Counterflow Heat Exchangers Using Various Compositions of an R13B1/R152a Nonazeotropic Refrigerant Mixture

摘要

Testing was performed with a nonazeotropic refrigerant mixture of R13B1/R152a to determine its ability to achieve capacity, relative to R/22, at low ambient temperatures. The selection of such a mixture could improve the efficiency of a heat pump by decreasing the cycling losses, which account for approximately 7-12% of the annual energy use, along with decreasing the amount of resistance heat required at low ambient temperatures. Results for the mixture show a potential capacity modulation from 12431 Btu/hr (3643 W) at 17 F (-8.3 deg C) to 8550 Btu/hr (2506 W) at 47 F (8.3 deg C) in heating and from 7451 Btu/h (2184 W) at 82 F (27.8 deg C) to 9188 Btu/h (2693 W) at 95 F (35 deg C) in cooling. An analysis of the coefficients of performance for the mixture and its pure components is presented along with a comparison against results obtained with R/22. The comparison is based on maintaining equivalent inlet and exit water temperatures in the evaporator and condenser for both R/22 and the mixtures. 4 refs., 8 figs., 4 tabs. (ERA citation 13:018429)