CO_2跨临界循环和氟利昂制冷剂循环性能分析

Performance Analysis of CO_2 Transcritical Compression Cycle and Freon Refrigeration Cycle

本文以R134a、R290和CO2制冷剂为研究对象,分别对三种单、双级循环的性能进行对比。结果表明,随蒸发温度增加、压缩机效率升高和冷凝器出口温度降低,所有循环性能均提高,单级CO2循环存在最优排气压力;用膨胀机代替节流阀可以显著提高CO2跨临界循环COP;低压级压缩机的效率比高压级压缩机对系统性能影响明显。双级循环中,CO2循环最优中间压力远高于其它两种循环。本研究为高效、节能的空调和热泵产品开发提供基础资料。

Based on refrigerants R134a,R290 and CO2,the performance comparison of three kinds of single stage compression cycle and two stage cycle were employed.The results shows that the performances COP of all cycles are gradually increased with the evaporation temperature and compressor efficiency increasing,and the single stage CO2 transcritical cycle has an optimal discharge pressure.Replace the throttle with an expander can significantly improve the system coefficient of performance of CO2 transcritical cycle.The low stage compressor efficiency has an important effect on the performance of two stage compression cycle than the high stage compressor efficiency and the CO2 transcritical cycle has a higher optimal intermediate pressure than other cycles.Some fundamental data were obtained for improving cycle performance and developing the CO2 refrigeration air-conditioning and heat pump water heater products.