二甲醚用作汽车空调制冷剂的实验研究

根据二甲醚的热物理性质对二甲醚的制冷循环性能进行了分析,并在R134 a汽车空调系统上对二甲醚的制冷性能进行了测试。结果表明:由于二甲醚的气相和液相黏度都比较小,使用二甲醚作为制冷剂可以减小系统的阻力,有利于系统制冷性能的提高。二甲醚可以直接灌注式替代R134 a,但会造成蒸发器出口过热度降低,需对膨胀阀弹簧预紧力进行调整,才能充分发挥二甲醚的制冷性能。

An Experimental Study on Dimethyl Ether as Refrigerant for Auto Air Conditioner

The refrigeration performance of dimethyl Ether (DME) is analyzed according to its thermodynamic properties,and some tests are carried out on a bus air conditioner originally using refrigerant R134a.The results show that due to the low viscosity of DME in both gaseous and liquid phases,the pressure drop in DME refrigeration system can be reduced and refrigeration efficiency improved.DME can be directly filled into auto air conditioner to replace R134a,but the spring pretension of thermal expansion valve should be slightly increased to raise superheat degree at evaporator outlet for ensuring the refrigeration efficiency of DME.