R290/R600a混合工质制冷系统泄漏点对系统性能的影响

混合工质在不同位置的泄漏所引起的系统中工质对组分比例发生变化会对制冷系统的性能产生很大影响。根据混合法则,从理论上研究R290/R600a工质对泄漏率在5%~40%范围内8种泄漏率条件下,系统工质对组分变化的规律。按照理论计算的要求建立制冷系统工质泄漏实验台,对实验台在4种泄漏率条件下的蒸发压力、冷凝压力、制冷量和COP进行研究。计算和实验结果表明,在蒸发器出口和冷凝器入口处的泄漏使低沸点组分R290在工质对中的比例增大,系统制冷量增加且COP下降;在蒸发器入口和冷凝器出口处的泄漏使高沸点组分R600a在工质对中的比例增大,系统制冷量下降且COP上升。

Effect of the leakage points of R290/R600a on the performance of refrigeration system

The change of the mass rate of the components caused by the leakage of the mixtures at different position will play an important role on the performance of the refrigeration system.According to the state law and the mixture principle,studies the change law of the mass rate in the system theoretically when the leakage of the mixture R290/R600a is from 5% to 40%.Based on the theoretical requirement,sets up the experimental table of the leakage of the mixture.Studies the evaporating pressure,the condensing pressure,the capacity and the COP of the experimental refrigeration system under four different mass leakage rate.The calculation and the experimental results show that the liquid leakages at the outlet of the evaporator and the inlet of the condenser will result in the rising of R290 rate in the mixture,the increase of the capacity and the decrease of COP of the system,while the gas leakages at the inlet of the evaporator and the outlet of the condenser will result in the increase of R600a,the decrease of the capacity and the increase of COP of the system.