Heat pump operating with a mixture of fluids

The coefficient of performance of a heat pump system comprising an external heat exchange medium may be increased if a non-azeotropic mixture of hydrocarbons or freons as working fluid is used so that it vaporizes or condenses with a change in temperature of the external fluid, i.e., the heat exchange medium. The aim of the research project was the selection of suitable mixtures and the investigation of their properties, the study of the operation of a heat pump using such mixtures by means of a mathematical model and experimental tests, as well as by a technico-economic analysis of actual applications in domestic heating systems and in the industrial sector.