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建立一维喷射热泵(EHPC)系统热力学模型,以R245fa为制冷剂,采用能量分析和(火用)分析相结合的方式,分析设计工况的变化对喷射器及系统性能的影响.计算结果表明:当发生温度升高时,喷射系数及系统热效率(COPh)增大,(火用)效率降低;当蒸发温度升高时,喷射系数和COPh,(火用)效率均增大;当冷凝温度升高时,喷射系数和COPh减小,(火用)效率升高;该系统适宜的工作范围为蒸发温度-15℃以上、冷凝温度45℃以下.“,”A 1-D ejector heat pump cycle (EHPC) model was developed.Using R245fa as the working fluid,both energy and exergy analyses were carried out to investigate the variations of the ejector and system performance in terms of the design conditions.It can be derived that when the generating temperature increases,both of the entrainment ratio of the ejector and the system coefficient of performance (COPh) of EHPC increase,while the exergy efficiency of the system decreases;when the evaporating temperature increases,the entrainment ratio of the ejector,COPh,and exergy efficiency of EHPC all increase;when the condensing temperature increases,both of the entrainment ratio of the ejector and COPh of EHPC decrease,while the system exergy efficiency increases.In addition,the evaporating temperature above-15 ℃ and the condensing temperature below 45 ℃ are suitable for the system.