R1234yf热泵技术综述与潜力分析

为了满足逐步严苛的环保法规要求,R1234yf成为车用热泵制冷剂R134a的热门替代制冷剂之一。本文对R1234yf热泵技术的研究进行了综述与分析,其GWP<1,各方面性质均符合车用热泵系统的工作需求。在传热效果上,R1234yf的沸腾传热性能略优于R134a,且冷凝过程压降比R134a低5%~10%,优于R134a系统。在诸多R1234yf和R134a系统的仿真和实验研究中,R1234yf热泵性能略低于R134a,但可以通过优化零部件、强化补气、改善工况等方式使其与R134a十分接近甚至超越。R1234yf低压饱和压力比R134a高约15%,可以适配更高的压缩机转速,低温下制热性能比R134a更好,且较低的压缩机排气温度使系统工作更为稳定,强化补气的效果也优于R134a。因此,R1234yf在车用热泵中具有较好的工作性能和发展前景,可以作为R134a的替代制冷剂。

Review and Potential Analysis of R1234yf Heat Pump Technology

To meet the gradual and stringent environmental regulations,R1234yf becomes one of the popular alternative refrigerants for vehicle heat pump refrigerant R134a.The research on R1234yf heat pump technology is reviewed and analyzed in this paper.The properties of R1234yf are in line with the work requirements of vehicle heat pump systems with the global warming potential(GWP)of less than 1.The system operation characteristics and performance are also very similar to R134a.In terms of heat transfer,the boiling heat transfer performance of R1234yf is slightly better than that of R134a.The condensation heat transfer coefficient is different in the research conclusions of various scholars,but the pressure drop in the condensation process of R1234yf is 5%-10%lower than that of R134a,which benefits the performance improvement.In the simulation and experimental research of many R1234yf and R134a systems,the performance of R1234yf heat pump is similar to R134a,but it can surpass R134a by optimizing components,economized vapor injection(EVI),and improving working conditions.R1234yf’s saturation pressure at a low saturation temperature is approximately 15%higher than R134a and can adapt to higher compressor speeds.Therefore,it has a better heating performance at low temperatures than R134a;its lower compressor discharge temperature makes the system work more stable.The relative improvement using EVI is also better for R1234yf than for R134a.Therefore,R1234yf has a better working performance and prospects for vehicle heat pumps and can,therefore,be used as an alternative refrigerant for R134a.