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Experimental Evaluation of Two Refrigerant Mixtures in a Breadboard Air Conditioner.


pdf icon Experimental Evaluation of Two Refrigerant Mixtures in a Breadboard Air Conditioner. (2883 K)
Mulroy, W.; Kauffeld, M.; McLinden, M.; Didion, D.

DOE (U.S. Department of Energy)/ORNL (Oak Ridge National Laboratory) Heat Pump Conference. Proceedings. April 1988, Washington, DC, 1988.

Keywords:

refrigerants; mixtures; air conditioning; heat pum; evalution; heat transfer; temperatre; temperature profiles; enthalpy

Abstract:

An experimental, water-to-water, breadboard heat pump (that is one designed to be easily reconfigured) was constructed for comparison of pure R22 to the refrigerant mixtures R22/R114 and R13/R12. three evaporator configurations were extensively studied. In all cases the best mixture out performed R22. The best efficiency with R22/R114 was 32% higher and with R13/R12 was 16% higher than the best efficiency measured with R22. Other observations were, first, that mixtures take advantage of heat exchanger efficiency that, in a gliding temperature application, a pure refrigerant is incapable of utilizing. Secondly, that heat exchange between the condensed and evaporating refrigerant is beneficial to some mixed refrigerants. Finally, mixtures exhibit nonlinearity of enthalpy versus temperature in the two phase region which has significant impact on both heat exchanger and cycle design.