中文摘要：

对涡流分离热气体再加热的CO2热泵系统进行热力性能分析，并与相同运行工况下的节流降压CO2热泵系统的性能进行了对比，得出涡流分离热气体再加热的CO2热泵系统存在最优的高压压力，在最优的高压压力下，系统获得最大的制热性能系数。提高分离热气体质量比、中间压力、蒸发温度、涡流管制热效应，降低气体冷却器出口温度，涡流分离热气体再加热的CO2热泵系统的制热性能系数提高。随着热气体质量比的增加和气体冷却器出口温度的升高，涡流分离热气体再加热的CO2热泵系统最优的气体冷却器出口压力也升高。在热气体质量比仅为0．2时，涡流分离热气体再加热的CO2热泵系统相比节流降压CO2热泵系统，最佳的制热性能系数提高11％。随着热气体质量比的增加，差值会进一步增大。气体冷却器出口温度的升高，对涡流分离热气体再加热的CO2热泵系统制热性能系数的影响要小于对节流降压CO2热泵系统的制热性能系数的影响。

英文摘要：

Abstract： The CO2 heat pump system with reheating of vortex separation hot gas is designed. The thermal performances of this CO2 heat pump system with reheating of vortex separation hot gas are analyzed and compared with that of the CO2 heat pump sys- tem of throttle at the same running condition. The following conclusions are obtained. The CO2 heat pump system with reheating of vortex separation hot gas has the optimal high pressure, and has maximum coefficient of performance （COP） for heating at this optimal high pressure. The coefficient of performances for heating of the CO2 heat pump system with reheating of vortex separation hot gas can be improved by increasing the mass ratio of hot gas, middle pressure, evaporation temperature, heating effect, as well as by decreasing the temperature of gas-cooler outlet. The optimal pressure of gas-cooler outlet of this CO2 heat pump system with re- heating of vortex separation hot gas rises with the increasing of the mass ratio of hot gas and temperature of gas-cooler outlet. At the mass ratio of hot gas is only 0.2, the maximum coefficient of performance for heating of the CO2 heat pump system with reheating of vortex separation hot gas compared with the CO2 heat pump system of throttle increases of 11%, and the difference value will increase further with the increasing the mass ratio of hot gas. The effect of temperature of gas-cooler outlet increasing on the coefficient of performances for heating of the CO2 heat pump system with reheating of vortex separation hot gas is less than that of the CO2 heat pump system of throttle.