针对跨临界CO2制冷循环中CO2工质的高密度和大压差影响阀片设计的问题,建立了专项的压缩机阀片位移实验装置和p-V图实验装置,由此展开了压缩机排气阀片的动态运动规律的实验研究,结果表明:影响阀片运动的主要因素包括压比、阀片升程、阀片厚度、弹簧刚度和压缩机转速等.实验测试表明:低压比、小升程有助于提高阀片的可靠性,高转速可以提高压缩机的容积效率,但同时提高了阀片的撞击速度;降低吸、排气过程的能量损失,尤其是排气起始阶段的能量损失,有助于提高压缩机的效率.%A test system for measuring valve displacement and p-V diagrams was established and the experiment on the dynamics of the discharge valves was conducted to understand the influences of the large density and high pressure difference across the reciprocating compressor valves on the valve dynamics in a transcritical CO2 refrigeration cycle. The results show that main factors affecting the valve movement include pressure ratio, valve lift, valve thickness, spring stiffness, and compressor speed. Moreover, a lower pressure ratio and smaller valve lift would enhance the valve reliability. A higher rotation speed would raise the volumetric efficiency of the compressor while it would increase the valve impact velocity. It appears that the compressor efficiency could be improved by reducing the energy loss in the suction and discharge process, especially in the beginning period of the discharge process.
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