两相CO_(2)喷射器混合室直径优化与模拟分析  

Optimization and Analysis of Mixer Diameter of Two-phase CO_(2) Ejectors

作　　者：龙俊安 宋霞 施骏业[1,2] 陈江平 Long Jun′an;Song Xia;Shi Junye;Chen Jiangping(Institute of Refrigeration and Cryogenics,Shanghai Jiao Tong University,Shanghai,200240,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]上海高效冷却系统工程技术研究中心,上海200240

出　　处：《制冷学报》2023年第1期122-128,共7页Journal of Refrigeration

基　　金：国家自然科学基金(51776119)资助项目。

摘　　要：混合室直径对两相喷射器的性能影响显著。结合湍流射流理论,本文提出两相喷射器混合室直径的射流分析设计方法:当混合射流的流量增至喷射器的目标总流量时,射流外边界的直径即为最优混合室直径。根据该方法优化某型号CO_(2)喷射器的混合室直径,引射比为0.5时的最优直径为2.4 mm。利用数值模拟研究混合室直径对CO_(2)喷射器性能的影响,结果表明:在相同条件下,混合室最优直径为2.2 mm。当混合室直径为2.4 mm时,喷射器压升为0.9 MPa,相比优化前提高了57.9%。结合射流理论,拟合了无量纲最优混合室直径的关联式。当引射比为0.4~0.8时,无量纲最优直径为1.7~2.1。关联式的预测结果与CFD模拟结果相差-6%~10%,可用于工程上预估最优混合室直径。Mixer diameter significantly influences the performance of two-phase ejectors.This study proposes a design method for the mixer diameter of two-phase ejectors based on the turbulent jet mixing mechanism.When the mass flow rate of the mixed jet increases to the target total mass flow rate of the ejector,the diameter of the jet′s external boundary should be the optimal mixer diameter.The mixer diameter of a CO_(2)ejector is optimized based on this method.The optimal diameter is 2.4 mm when the entrainment ratio is 0.5.The performance of the two-phase CO_(2)ejector is investigated for varying mixer diameters via numerical simulation.The results show that the optimal diameter is 2.2 mm under the same condition.When the mixer diameter is 2.4 mm,the pressure lift is 0.9 MPa,which is 57.9%higher than the baseline performance.Based on the turbulent jet theory,this study also proposes a correlation for the dimensionless optimal mixer diameter.The dimensionless optimal mixer diameter ranges from 1.7 to 2.1 when the entrainment ratio is 0.4-0.8.The correlation exhibits a-6%-10%deviation from the CFD simulation results and can be used to predict the optimal diameter.

关 键 词：喷射器 混合室 两相流 射流 优化 

分 类 号：TB611[一般工业技术—制冷工程] TB657.5