超高温热泵混合工质性能研究

Study on the Performance of Very High Temperature Heat Pump Mixtures

性能良好的工质是超高温热泵技术开发的关键之一。针对供热温度大于140℃的超高温热泵,根据优势互补的原则,提出了四种性非共沸混合工质MB1、MB2、MB3、MB4,并在蒸发温度50℃、70℃与90℃,冷凝温度140℃-160℃工况下对这四种混合工质的循环性能及最佳配比进行了研究。结果表明,苯,环戊烷,甲苯,丙酮及R13336mzz(Z)可作为该供热温度下热泵的混合工质的组分;四种混合工质性能良好,其中,MB2的循环性能在所提出的混合工质中最优,在蒸发温度50℃,冷凝温度160℃工况下,COP达2.4,[火用]效率达58.9%;在蒸发温度90℃,冷凝温度160℃工况下,COP达4,[火用]效率达62.6%。其它混合工质较主要成分苯的循环性能均有提升,MB4较苯可燃性降低。

Good working fluid is one of the keys to the development of very high temperature heat pump technology.In this paper,according to the principle of complementary advantages,four non-azeotropic mixtures MB1,MB2,MB3 and MB4 are proposed for very high temperature heat pumps with heating temperatures greater than 140 C,and the cycle performance and optimal ratio of these four mixtures are studied under the conditions of evaporation temperature of 50℃,70℃and90℃C andcondensationtemperatureof140°℃-160℃.Theresultsshowthatbenzene,cyclopentane,toluene,acetone and R13336mzz(Z)can be used as components of the mixtures of the heat pump at the heating temperature.The four mixtures have good performance,among which the cycle performance of MB2 is the best among the proposed mixed working fluids,and the COP reached 2.4 and the exergy efficiency reached 58.9%under the conditions of evaporation temperature of 50℃andcondensationtemperatureof160℃.Undertheconditionsof evaporation temperature of 90 C and condensation temperature of 160℃C,theCOP ofMB2reached4andtheexergy efficiency reached 62.6%.The cycle performance of other mixtures was improved compared with the main component benzene,and the flammability of MB4 was lower than benzene.