两相CO_(2)喷射器混合室长度和扩压室角度影响研究  

Effects of Mixer Length and Diffuser Angle on Two-Phase CO_(2)Ejector

作　　者：龙俊安 潘美娜 施骏业[1,3] 陈江平 Long Junan;Pan Meina;Shi Junye;Chen Jiangping(Institute of Refrigeration and Cryogenics,Shanghai Jiao Tong University,Shanghai,200240,China;Nanjing University of Aeronautics and Astronautics,Nanjing,210016,China;Shanghai High Efficient Cooling System Research Center,Shanghai,200240,China)

机构地区：[1]上海交通大学制冷与低温工程研究所,上海200240 [2]南京航空航天大学能源与动力学院,南京210016 [3]上海市高效冷却系统工程技术研究中心,上海200240

出　　处：《制冷学报》2025年第1期132-139,共8页Journal of Refrigeration

基　　金：国家自然科学基金(51776119)资助项目。

摘　　要：利用已验证的CFD模型研究不同工况下混合室长度和扩压室锥半角对喷射器升压性能的影响。结果表明:在给定工况下,存在最优的混合室长度和扩压室角度参数组合使喷射器的升压性能最高。两者对喷射器性能的影响具有强相关性:当混合室足够长时,掺混较为充分,混合流扩压时不易发生流动分离,扩压室锥半角在0.5°~3°变化对喷射器性能的影响相对较小;而混合室较短时,扩压室壁面附近容易产生湍流损失,扩压室角度的影响较大。此外,最优结构参数受到运行工况的影响,随喷嘴入口压力和温度降低,最优混合室长度增加,最优扩压室角度减小。在研究工况和喷嘴配置下,喷射器最优混合室长度约为38 mm,最优扩压室锥半角为1°~1.5°。This study employed a validated computational fluid dynamics(CFD)model to investigate the influences of the mixer length and diffuser angle on the ejector pressure-recovery performance.The results demonstrated that an optimal combination of mixer length and diffuser angle exists at which the ejector has the highest performance.The effects of these two geometrical parameters on the ejector performance were highly consistent.When the mixer length was sufficiently long,the mixing was sufficient,and the mixed flow was not subjected to separation during pressure recovery.Under these circumstances,the effect of the diffuser angle on the ejector performance was relatively trivial,varying between 0.5°and 3°.However,when the mixer length was short,the flow was prone to turbulent losses near the diffuser wall.In this case,the effect of the diffuser angle was significant.In addition,the optimal geometries were affected by the operating conditions.The optimal mixer length increased as the nozzle inlet pressure and temperature decreased,whereas the optimal diffuser angle decreased.Under the conditions and nozzle configuration investigated in this study,the optimal mixer length was approximately 38 mm and the optimal diffuser cone half angle was between 1°and 1.5°.

关 键 词：两相流 CO_(2)喷射器 混合室 扩压器 

分 类 号：TB611[一般工业技术—制冷工程] TB657.5