A Fortran-language computer program for simulating the operation of a water-cooled vapor-compression heat pump in any orientation with respect to gravity has been developed by modifying a prior general-purpose heat-pump design code used at Oak Ridge National Laboratory (ORNL). Although it is specific to the design of a high-temperature-lift heat pump for the International Space Station, this program could serve as a basis for development of general-purpose computational software for designing and analyzing liquid-cooled heat-pumps. The ORNL program contained models of refrigerant-fluid-to-air heat exchangers; the main modification consisted in replacing those models with models of plate-type heat exchangers utilizing water as both the cooling and the heating source liquid.
The present program incorporates a Fortran implementation of the American Society of Mechanical Engineers water-properties tables. Semi-empirical models of the heat transfer coefficients for these heat exchangers were developed from vendor and laboratory test data, inasmuch as applicable published correlations were not available. The program produces estimates of evaporator and condenser capacities, coefficients of performance, and operating temperatures over a range of compressor speeds.
This work was done by Duane Bozarth of H and R Technical Associates for Johnson Space Center. MSC-23375-1