旁路结构对亚临界喷射器引射效率的影响-《郑州大学学报(工学版)》

文章信息/Info

Title:: Influence Analysis of the Bypass Structure on Entrainment Ratio of a Subcritical Ejector

Author(s):: LIU Huadong; JIN Zhaoyang; WANG Dingbiao; HAO Qi; DANG Hao; ZHANG Yuxiang; School of Mechanical and Power Engineering, Zhengzhou University, Zhengzhou 450001, China

Keywords:: entrainment ratio; inlet angle; inlet width; inlet pressure; bypass ejector

摘要:: 针对传统喷射器引射率偏低的问题,通过设置旁路来改善其内部流场。采用数值模拟方法研究了旁路进口角度、宽度和介质压力对喷射器内流体压力、速度、流场以及引射效率的影响规律,探寻研究范围内的最佳参数匹配,并与传统喷射器效率进行对比。结果表明:喷射器结构尺寸、工作流体和引射流体工况固定时,引射系数随旁路进口角度增加先增加后减小;引射系数随旁路进口角度、旁路进口宽度、旁路进口压力的增加先增加后减小, 存在最佳旁路进口宽度、进口角度和最优旁路进口压力使两相旁路喷射器引射系数最大。在所研究范围内,最佳旁路进口角度为 15°,进口宽度为 3 mm,最佳旁路进口压力为 618. 5 kPa;与传统喷射器相比,相同工况时,最佳结构尺寸和旁路进口压力下的两相旁路喷射器引射系数提高了 25. 7% ~ 56. 8%。

Abstract:: Regarding to the low efficiency, a bypass structure was set to improve the internal fluid of a traditional ejector. Computational fluid dynamics was conducted to study the influence of the structure and the working parameters of the bypass on the flow field, including the bypass inlet angle, width and the flow pressure. The optimum matching parameters was also investigated. Based on the simulation results, when all other parameters of the ejector were fixed, the entrain ratio increased firstly and then decreased with the increase of the inlet angle, the width and the flow pressure of the bypass, respectively, and there existed the optimum parameters. In this investigation, the optimum inlet angle, width and the flow pressure of the bypass was 15°, 3 mm and 618. 5 kPa. Compared with the traditional ejector, the entrainment ratio of the bypass ejector could be increased by 25. 7% - 56. 8% in the same conditions.