低品位热驱动的混合工质喷射制冷循环研究

A MIXED-REFRIGERANT EJECTOR REFRIGERATION CYCLE DRIVEN BY LOW GRADE HEAT

提出一种低品位热驱动的混合工质喷射制冷循环,将沸点相差较大的非共沸混合工质引入喷射制冷循环,采用两级分凝分离降低该新循环压比,实现在喷射制冷循环中获得较低的制冷温度和较高制冷效率。建立组成循环各部件热力学数学模型,在系统稳定运行的条件下,分析喷射器压比、冷凝温度和混合工质组分配比对新循环工作性能的影响。研究表明:采用混合工质R600/R290的喷射制冷循环可获得低于-20℃的制冷温度。

A mixed-refrigerant ejector refrigeration cycle driven by low grade heat was proposed. The non-azeotropic mixed working substances with much different boiling points were led to the ejector refrigeration cycle, two grade separate and segregation were used to decrease the pressure ratio of the ejector refrigeration cycle, and lower refrigeration temperature and higher refrigeration efficiency were obtained. Based on the thermodynamic models on components, the influences of pressure ratio of the ejector, outlet temperature of condenser and mass composition ratio of mixed refrigerant on operation performance of new cycle were analyzed. The results indicate that the novel cycle can obtain the refrigeration temperature lower than -20℃ by using the mixed refrigerant R600＋R290.