工况对两相流引射器制冷循环系统性能的影响

Effects of operating conditions on performance of two-phase ejector refrigeration cycle system

引射器结构简单、无运动部件，在制冷系统中代替膨胀阀可提高系统的COP。以R134a为工质，实验研究了不同工况条件下两相流引射器制冷循环系统性能，分析了蒸发温度、冷凝温度对引射比、压力提升比、制冷量和系统COP的影响。研究发现：当冷凝温度为40℃时，随着蒸发温度的提高，引射比和压力提升比均下降，制冷量和系统COP均提高；当蒸发温度为-10℃时，随着冷凝温度的增加，引射比和压力提升比均增大，制冷量和系统COP均下降。

The ejector has the advantages of simple structure and no moving parts. By using ejector instead of expansion valve in the refrigeration system, the COP of the system can be improved. The experimental studies on the performances of the two-phase ejector refrigeration systems with the refrigerant R134a as working fluid under different conditions were carried out. The influences of the evaporating and condensing temperatures on the entrainment ratio, pressure lifting ratio, refrigeration capacity and system COP were analyzed. The experimental results indicate that the entrainment ratio and pressure lifting ratio decrease with the increase of evaporating temperature at the condensing temperature of 40℃. The entrainment ratio and pressure lifting ratio increase, while the refrigeration capacity and system COP decrease with the increase of condensing temperature at the evaporating temperature of - 10℃.