Study on the impact of a novel honeycomb gas cooler on the performance and discharge pressure control of a transcritical CO₂ heat pump system

For improving the performance of transcritical CO₂ air source heat pump (ASHP), in our previous work, a new type honeycomb gas cooler with high compactness, pressure bearing capacity, and heat exchange capacity was proposed. To investigate the impact of the honeycomb gas cooler on the performance of transcritical CO₂ ASHP system, a steady-state mathematical model of the system is established in this paper. Also, the effects of key parameters on the coefficient of performance (COP) and optimal discharge pressure of the system are studied. The results indicate that the influence weight of evaporation temperature, outlet/inlet water temperature and pinch point temperature difference on the optimal discharge pressure accounts for more than 94.36 %. In addition, a correlation formula of optimal discharge pressure is established with these four parameters as independent variables, and the maximum deviation between theoretical and simulated values of optimal pressure and COP is 10.74 % and −11.80 %, respectively.