室外蒸发器前加气液分离器对霜层分布和换热量的影响  

A study on heat distribution and frost formation of an outdoor evaporator with optimized gas-liquid separator added in heat pump air conditioning system for electric vehicle

作　　者：苗言明 胡家云 谭明飞 夏丁羽 李超 何其泽 王佳韵 李康[1,2] MIAO Yanming;HU Jiayun;TAN Mingfei;XIA Dingyu;LI Chao;HE Qize;WANG Jiayun;LI Kang(Integrated New Energy Vehicle Thermal Management Evaluation in Shanghai Power Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China;School of Energy and Power Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China;Shanghai Investigation Design&Research Institute Co.,Ltd.,Shanghai 200093,China;Shanghai Fire Research Institute Ministry of Emergency Management,Shanghai 200032,China)

机构地区：[1]上海理工大学新能源车辆热管理综合评估实验室,上海200093 [2]上海理工大学能源与动力工程学院,上海200093 [3]上海勘测设计研究院有限公司,上海200093 [4]应急管理部上海消防研究所,上海200032

出　　处：《流体机械》2025年第2期8-15,57,共9页Fluid Machinery

基　　金：国家自然科学基金面上项目(52376203)。

摘　　要：针对目前电动汽车热泵空调系统在低温条件下,室外蒸发器表面普遍容易结霜,进而影响换热效率、系统性能及续航里程等一系列问题,研究发现,由于蒸发器中制冷剂两相的热交换能力不同,导致结霜现象不均匀,进而对系统性能产生负面影响。为此,本文提出在室外蒸发器前添加气液分离器的方案,通过调节气相旁通阀的开度来优化蒸发压力,改善蒸发器和系统的整体性能。通过对比气相旁通阀最佳开度和0开度条件下,在不同环境温度(-5,0,5 ℃)、蒸发压力(0.199,0.242,0.291 MPa)、压缩机转速(2 000,3 000,4 000 r/min)时,系统换热效率、COP、蒸发器出口温度的变化趋势,结果表明,添加气液分离器后,换热效率最高提升6.9%,COP最高提升7.4%,蒸发器出口空气温度提升了3.6%~11.2%。这一改进设计能够有效缓解低温条件下的结霜问题,提升系统性能。In responese to the current low temperature conditions of electric rehicle heat pump air conditioning systems,the surface of the outdoor evaporator is prone to frosting,which in turn affects the heat transfer efficiency,system performance,and driving range.Existing research has found that due to the different heat exchange capabilities of the two phases of the refrigerant in the evaporator,the frosting phenomenon is uneven,thus having a negative impact on the system performance.To address this issue,this paper proposes a solution of adding a gas-liquid separator in front of the outdoor evaporator.By adjusting the opening degree of the gas-phase bypass valve,the evaporation pressure can be optimized,and the overall performance of the evaporator and the system can be improved.By comparing the specific variation trends of the system's heat transfer efficiency,coefficient of performance(COP),and the outlet temperature of the evaporator under the conditions of the optimal opening degree of the gas-phase bypass valve and zero opening degree,at different ambienttemperatures(-5,0,5℃),evaporation pressures(0.199,0.242,0.291 MPa),and compressor speeds(2000,3000,4000 r/min),the experimental results show that after adding the gas-liquid separator,the heat transfer efficiency is increased by up to 6.9%,the COP is increased by up to 7.4%,and the outlet air temperature of the evaporator is increased by 3.6%~11.2%.This improved design can effectively alleviate the frosting problem under low-temperature conditions and enhance the system performance.

关 键 词：电动汽车 气液分离器 热泵系统 热泵性能 

分 类 号：TU83[建筑科学—供热、供燃气、通风及空调工程]