碳氢混合工质对自复叠制冷循环系统性能影响的实验研究
Experimental study on influence of hydrocarbon blends on performance of auto-cascade refrigerating cycle systems
摘要：
为了研究碳氢(HC)混合工质对自复叠制冷循环(ARC)系统性能的影响,本文针对一套典型三级ARC系统,选用R600a、R1150及R50,研究不同配比HC混合工质对吸排气温度、吸排气压力、蒸发温度、系统制冷量及COP的影响,并与采用R600a/R23/R14混合工质的ARC系统进行了性能对比。结果表明:随着混合工质中R1150质量分数从15%增大至31%,系统的蒸发温度、吸排气压力及排气温度上升均超过4.64%,导致系统制冷量和COP分别下降约5%～8%和17.5%～30.0%;而随着R50质量分数从2%增大至12%,系统的吸排气压力及温度仍呈上升趋势,但蒸发温度降低,最大降幅22.79%,进而提高制冷量约14.49%～20.82%,系统COP下降超过8.91%;采用HC混合工质的ARC系统排气温度较R600a/R23/R14系统高15 ℃左右,但其压缩机压比和功率波动分别降低了27%和57%。
Abstract：
In order to study the influence of hydrocarbon (HC) blends on the performance of auto-cascade refrigerating cycle (ARC) systems,this paper selects R600a,R1150 and R50 for a typical three-stage ARC system to study the influence of different ratios of HC blends on suction and discharge temperatures,suction and discharge pressures,evaporation temperatures,system refrigeration capacity and COP,and compares the performance with that of an ARC system using the blends of R600a/R23/R14.The results show that with the increase of the mass fraction of R1150 in the blends from 15% to 31%,the evaporation temperature,suction and discharge pressures and discharge temperature of the system all increase by more than 4.64%,which leads to the decrease of system refrigeration capacity and COP by about 5% to 8% and 17.5% to 30.0%,respectively.With the increase of R50 mass fraction from 2% to 12%,the suction and discharge pressures and temperatures of the system are still on the rise,but the evaporation temperature decreases,with the largest decrease of 22.79%,which improves the refrigeration capacity by about 14.49% to 20.82%,and decreases the COP of the system by more than 8.91%.The discharge temperature of the ARC system using HC blends is higher than that of the R600a/R23/R14 system by 15 ℃,but the pressure ratio and power fluctuation of its compressor are reduced by 27% and 57%,respectively.
Keywords:auto-cascade refrigerating cycle system; hydrocarbon blend; component ratio; mass fraction; system performance; suction and discharge temperatures; suction and discharge pressures; refrigerant substitution