双级压缩制冷系统替代制冷剂性能对比研究

Comparative Study on Performance of Alternative Refrigerant in Two-Stage Compression Refrigeration System

为研究可替代制冷剂,提高循环性能参数,利用MATLAB结合NIST对承载R410A,R32,R404A和R507A共4种制冷剂的一次节流中间不完全冷却的两级压缩制冷循环系统进行模拟,课题组对比分析高压级压缩机排气温度、系统能效比(coefficient of performance,COP)、单位制冷量和制冷剂流量对蒸发温度从-44℃上升到-30℃时的动态响应,研究4种制冷剂在两级压缩中的具体性能差异,以期对制冷剂的选择做出相应的指导。结果表明:4种制冷剂中R32的高压级压缩机排气温度偏高,但其单位制冷能力最大,制冷剂流量最小; R507A对蒸发温度的动态响应最为强烈;制冷剂R507A和R404A各项性能指标接近; R32的CCOP最高,比R410A高约3. 9%,比R404A和R507A分别高约14. 03%和12. 40%。通过对数据研究对比发现,4种制冷剂中R32的各项性能更为出色,作为一种新型的环保制冷剂,有很大的发展潜力。

In this paper,a two-stage compression refrigeration cycle system with incomplete cooling in the middle of one throttle carrying four refrigerants R410A,R32,R404A and R507A were simulated by MATLAB combined with NIST.When the evaporation temperature went up from-44℃ to-30℃,the dynamic response of high-pressure compressor exhaust temperature,the COP(coefficient of performance)of system,unit refrigerating capacity and refrigerant flow rate were contrasted and analyzed.The specific performance differences of four refrigerants in two-stage compression were studied in order to provide guidance for the selection of refrigerants.The results show that the high-pressure compressor exhaust temperature of R32is high in the four refrigerants,but it has the largest refrigeration capacity and lowest refrigerant flow.R507A has the strongest dynamic response to evaporation temperature;the performance indexes of refrigerant R507A and R404A are close;the COP of R32is the highest of four refrigerants,which is about3.9%higher than R410A and about14.03%and12.40%higher than R404A and R507A.Through the comparison of data,it is found that R32has better performance among the four refrigerants.As a new environmental protection,R32has great development potential.