Development of a thermodynamic performance-analysis program for CO2 geothermal heat pump system

In this research, a steady-state cycle simulation program for thermodynamic performance analysis of CO2 geothermal heat pump systems was developed. A series of case studies were conducted by changing system parameters and operation conditions in order to investigate the effect of various system variables on the geothermal heat pump cycle including an internal heat exchanger (IHX). The simulation results were validated by comparing them with experimental data. The mean deviations of the COPs, cooling capacities, and compressor powers between experimental and simulation results are 4.5%, 3.8%, 6.5%, respectively at the 5 °C superheated degree and 32% EEV opening.