城市轨道车辆空调制冷系统性能研究

Research on performance of air conditioning and refrigeration system for urban rail vehicles

发展轨道交通成为各大城市解决交通拥堵的重要手段,而地铁列车空调制冷系统性能的优劣直接影响乘客旅途的舒适性,因此对于城市轨道车辆空调制冷系统性能的研究极其重要。针对城市轨道车辆制冷空调特殊双系统结构,建立换热器并联制冷系统仿真模型,并通过试验对其进行验证。研究了车内外环境温湿度、换热器风量、毛细管长度及蒸发器翅片间距对制冷系统性能的影响,得出换热器风量降低至60%~70%左右,制冷系统性能开始急剧下降,确定了毛细管最佳长度为375 mm,蒸发器最优翅片间距为2.2 mm。

The development of rail transit has become an important means to solve traffic congestion in major cities, and the performance of air conditioning and refrigeration system of subway trains directly affects the comfort of passengers’ journey, so it is extremely important to study the performance of air conditioning and refrigeration system.Aiming at the special dual system structure of refrigeration and air conditioning in urban rail vehicle, a simulation model of parallel refrigeration system of heat exchanger was established and verified by experiments.The effects of ambient temperature and humidity, air volume of heat exchanger, capillary length and fin spacing of evaporator on the performance of refrigeration system were studied in this paper. It is concluded that when the air volume of heat exchanger is reduced to about 60%-70%, the performance of refrigeration system begins to decline sharply. The optimal capillary length is 375 mm and fin spacing of evaporator is 2.2 mm.