Experimental evaluation of the effect of an internal heat exchanger on a transcritical CO_2 ejector system

作     者：Xiao-xiao XU Guang-ming CHEN Li-ming TANG Zhi-jiang ZHU Shuang LIU 

作者机构：Institute of Refrigeration and Cryogenics State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China 

出 版 物：《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 (浙江大学学报（英文版）A辑（应用物理与工程）)

年 卷 期：2011年第12卷第2期

页      面：146-153页

核心收录：

学科分类：080705[工学-制冷及低温工程] 08[工学] 0807[工学-动力工程及工程热物理] 

基　　金：Project supported by the National Basic Research Program (973) of China (No.2010CB227304) the National Key Technologies R & D Program in China (No.2006BAJ01A10) 

主　　题：CO2 ejector system Transcritical cycle Heating coefficient of performance (COPr) 

摘      要：This study presents experimental results focused on a performance comparison of a transcritical CO2 ejector system without an internal heat exchanger(IHX) (EJE-S) to a transcritical CO2 ejector system with an IHX(EJE-IHX-S) . The comparison includes the effects of changes in operating conditions such as cooling water flow rate and inlet temperature. Experiments are conducted to assess the influence of the IHX on the heating coefficient of performance(COPr) ,heating capacity,entrainment ratio,pressure lift,and other parameters. The primary flow rate of the EJE-IHX-S is higher than that of the EJE-S. The pressure lift and actual ejector work recovery are reduced when the IHX is added to the transcritical CO2 ejector system. Using a more practical performance calculation,the compression ratio in the EJE-S is reduced by 10.0%-12.1%,while that of EJE-IHX-S is reduced only by 5.6%-6.7% compared to that of a conventional transcritical CO2 system. Experimental results are used to validate the findings that the IHX weakens the contribution of the ejector to the system performance.