Correlation Between Volumetric Efficiency and Isentropic Efficiency of Piston Compressor of Thermal Pump

A relationship that establishes a correlation between the isentropic efficiency and volumetric efficiency of a piston compressor and that takes into account the dead volume, engine pressure ratio, and the state of the working body at the start of the compression process and its adiabatic index is obtained. With a pressure ratio greater than 3–4, the isentropic efficiency will be 3–12% higher than the volumetric efficiency.