R404A与CO2复叠式制冷系统的理论分析  

Theoretical Analysis of R404A/CO2 Cascaded Refrigeration System for Low Temperature

作　　者：赖艳华[1] 邵长波[2] 吕明新[1] 董震[1] 王庆为[1] 

机构地区：[1]山东大学能源与动力工程学院,250061 [2]山东商业职业技术学院,250103

出　　处：《冷藏技术》2011年第1期36-41,共6页Journal of Refrigeration Technology

基　　金：山东省科技攻关资助项目（2009GG20004023）

摘　　要：本文针对所建立的新型R404A／CO2复叠式制冷设备进行了理论研究，该系统可提供零下40℃以下的低温环境。根据R404A和CO2的物性特征及复叠式循环流程，通过数值模拟寻找一定工况下CO2低温级的最佳冷凝温度及二者的最佳质量流量比，分析冷凝蒸发器的工作温度、CO2侧蒸发温度、R404侧的冷凝温度等对R404A／CO2复叠式系统COP的影响。结果表明，为了提高循环效率并保证循环的安全运行，应尽可能地升高低温段蒸发温度、降低高温段冷凝温度，缩小冷凝蒸发器的传热温差，环保工质R404A和CO2的复叠式制冷系统在低温制冷条件下有良好的发展前景。A R404A/CO2 cascaded refrigeration equipment has been established, which can provide low er than -40℃ temperatures. Based on physical properties of R404A and CO2 and cascaded refrgeration cycle, through simulation and theoretical analysis, an optimum mass flow rate ratio and an optimum condensation temperature of low temperature cycle part are acquired at a definite evaporation temperature and temperature difference of condenserevaporator heat exchanger. Results show that increasing evaporation temperature of low temperature cycle, decreasing condensation temperature of R404A, and reducing the temperature difference in cascade heat exchanger are better way to improve COP of this system, at the same time ensuring the operation safety. It can be concluded that R404A/CO2 environmentally-friendly refrigerants cascaded refrigeration cycle has a good future.

关 键 词：R404A/CO2 复叠式制冷循环 COP 质量流量比 

分 类 号：TB61[一般工业技术—制冷工程]