Experimental Evaluation of Two Refrigerant Mixtures in a Breadboard Air Conditioner.
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.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899