摘要
本文在各种CO_2跨临界单级压缩制冷循环的基础上,建立了6种CO_2跨临界双级压缩制冷循环系统的热力学模型,并对中间压力、蒸发温度、气体冷却器出口温度、高压级和低压级压缩机效率等设计参数对系统性能系数(COP)的影响进行了分析和比较。结果表明,气体冷却器出口温度和低压级压缩机效率是影响系统COP的主要因素。同时,通过对比6种型式的双级压缩系统,发现在给定的高压压力下,二次节流中间不完全冷却形式的双级压缩系统在系统的性能系数和安全运行方面在这些双级压缩系统中是最好的。这些研究成果可为CO_2跨临界双级压缩制冷系统的优化设计提供参考。
Based on a variety of CO2 transcritical single stage compression refrigeration cycle, six thermodynamic models for CO2 transcritical two-stage compression refrigeration system were established in this paper, and the effects of the design parameters, including the evaporating temperature, the gas cooler outlet temperature, and the compressor efficiencies for high pressure stage and low pressure stage on the coefficient of performance （COP） in these systems were analyzed. The results showed that the outlet temperature of gas cooler and the compressor efficiency of low pressure stage are the major influencing factors for COP. At the same time, comparing the six systems, it was found that the performance coefficient and the operation safety in the two-stage compression system with incomplete cooling in the middle of the double-throttling were best among these systems under given high pressure conditions. The research results would provide the reference for the optimization design of CO2 transcritical two-stage compression refrigeration system.
出处
《制冷技术》
2016年第4期8-13,35,共7页
Chinese Journal of Refrigeration Technology
基金
天津市科技特派员项目(No.15JCTPJC62600)
关键词
CO2
跨临界双级压缩
性能系数
蒸发温度
二次节流
CO2
Transcritical two-stage compression
Coefficient of performance
Double-throttling
