Comparative analysis between the performances of reciprocating and rolling piston compressors applied to a domestic heat pump water heater

Abstract

This paper reports a comparative analysis of a reciprocating compressor and a rolling piston compressor, both optimized for a domestic heat pump water heater. The analysis involves a novel approach that couples the detailed modeling of each compressor to a lumped quasi-steady-state model for the remainder of the system operating under summer, winter and standard conditions. Considering the summer conditions, the COP of the heat pump operating with the rolling piston compressor was found to be 12.3% higher than when using the reciprocating compressor. The heat pump operating with the rolling piston compressor was also more efficient under winter conditions, but the COP was only 7.6% higher. The superheating and leakage losses in the rolling piston compressor remained almost the same with the two sets of operating conditions, but the losses in the suction and discharge systems of the reciprocating compressor were considerably lower under the winter operating conditions.