低GWP混合工质RE170/R134a用于汽车空调的性能分析

Performance Study of Low GWP Mixed Refrigerant RE170/R134a Used in Automobile Air Conditioner

当前汽车空调工质R134a存在温室效应指数太高(GWP=1300)的缺点,亟需寻找环保型工质进行替代。通过前期研究,筛选出混合工质RE170/R134a(90/10)(NCUR02)其ODP为0,GWP为130,环境性能较好。分析比较了NCUR02和R134a的热力性质,并建立汽车空调系统模型分别得到NCUR02和R134a在标准工况和变工况下的循环性能参数,同时利用焓差试验室,试验研究了NCUR02和R134a在4种国标规定测试工况条件下的循环性能。结果表明:NCUR02的温度滑移较小,标准大气压下小于0.1℃,且饱和压力线与R134a相近,属于近共沸混合工质;单位质量制冷量约为R134a的2倍,单位容积制冷量与R134a相当,循环性能系数COP比R134a提高了10%左右,工作压力略低于R134a,用于汽车空调系统性能表现更优。

At present,refrigerant R134a of automobile air conditioner has the disadvantages of high greenhouse effect index(GWP=1300),so it is necessary to find the environment-friendly refrigerant to replace it.Through the previous study,the mixture refrigerant RE170/R134a(90/10)(code NCUR02)was selected by screening.Its ODP is 0,GWP is 130,and its environmental performance is good.The thermodynamic properties of NCUR02 and R134a were analyzed and compared.The cycle performance parameters of NCUR02 and R134a under standard conditions and variable conditions were simulated by establishing an automobile air conditioning system model.And an enthalpy difference lab was used to study the cycle performance of NCUR02 and R134a under four test conditions of the international standard.The results show that for NCUR02:the temperature slip was relatively small,which is less than 0.1℃at standard atmospheric pressure;and the saturated pressure line was in good agreement with R134a,it belongs to near-azeotropic mixture refrigerant;Its refrigerating capacity per unit quality is twice that of R134a,volumetric refrigerating capacity is equivalent to R134a,the cycle performance coefficient COP is 10%higher than R134a,its working pressure is slightly lower than R134a,its performance shows better when used for automobile air conditioning system.