间接复叠空气源热泵在铁路高寒地区建筑供暖中最优中间温度研究

针对单级空气源热泵高寒地区运行能效和供水温度低,以及直接复叠空气源热泵除霜困难的问题,对通过低环境温度空气源热泵机组与水源热泵间接复叠的系统供暖型式进行了阐述,对影响室外空气源热泵机组与室内水源热泵机组的因素进行了分析,指出环境温度依然是影响系统能效的首要因素,同时,为实现间接复叠热泵系统的能效最大,对最优中间耦合温度进行了计算。对某地区铁路工区的运行结果进行了分析,结果表明,最优中间耦合温度随环境温度的降低而降低;以最优中间耦合温度控制下的间接复叠热泵系统可以应用于我国高寒地区。

Study on Optimal Intermediate Temperature of Indirect Cascade Air Source Heat Pump in Building Heating in High Cold Railway Areas

Aiming at the problems of low operating energy efficiency and water supply temperature of single-stage air-source heat pump in alpine region and dif ficulty in defrosting of direct cascade air-source heat pump,the heating type of indirect cascade system through low ambient temperature air-source heat pump unit and water-source heat pump unit is elaborated,the factors affecting outdoor air-source heat pump unit and indoor water-source heat pump unit are analyzed,and it is pointed out that ambient temperature is still the primary factor affecting system energy efficiency.At the same time,in order to realize the maximum energy efficiency of indirect cascade heat pump system,the optimal intermediate coupling temperature is calculated.The operation results of a railway work area in a certain area are analyzed.The results show that the optimal intermediate coupling temperature decreases with the decrease of ambient temperature.Indirect cascade heat pump system controlled by optimal intermediate coupling temperature can be applied to alpine regions in China.