节流口内空化流体的湍动特性  

Turbulence Characteristics of Cavitating Fluid in Orifice

作　　者：韩桂华[1] 侯进军 赵志伟 张艳芹[1] HAN Gui-hua;HOU Jin-jun;ZHAO Zhi-wei;ZHANG Yan-qin(School of Mechanical and Power Engineering, Harbin University of Science and Technology, Harbin 150080, China)

机构地区：[1]哈尔滨理工大学机械动力工程学院,哈尔滨150080

出　　处：《哈尔滨理工大学学报》2021年第6期66-72,共7页Journal of Harbin University of Science and Technology

基　　金：国家自然科学基金(51405113).

摘　　要：为了提高孔板空化器的水力空化强度并得到空化规律,考虑到脉动对空化模型的影响引入了脉动影响因子,得出流体脉动空化模型,采用多相流的方法通过Fluent软件得出流体的气液两相传质速率及湍流强度,最后得出流体空化规律。研究结果表明:当恢复压力一定时,适当增加入口压力可以提高流体的空化强度,在0.5~0.7 MPa可获得较大的空化强度,当压力继续增加时,使空化强度和发育程度均降低;相比于进口压力,出口压力对流体空化强度起主导作用,在0.4~0.6 MPa空化强度不断增强,当出口压力继续增加时,压差过小抑制了空化的发生;分析多孔出流的流体湍动模型和传质速率得出,在0.4~0.6 MPa多孔出流引起了流体的湍动叠加效应,导致空化强度增加。In order to improve the hydrodynamic cavitation intensity and obtain the cavitation law of orifice plate cavitator,Considering the influence of fluctuation on cavitation model,fluctuation influence factors were introduced.We obtained the fluid fluctuation cavitation model,using the method of multiphase flow to get mass transfer rate and turbulence intensity of gas-liquid two-phase through the Fluent software,and finally obtained the fluid cavitation law.The results showed that:When the recovery pressure is constant,increasing the inlet pressure properly can improve the cavitation intensity of the fluid,and a higher cavitation intensity is obtained between 0.5 and 0.7 MPa.Cavitation intensity and degree of development decrease as pressure continues to increase.Comparing with inlet-pressure,outlet-pressure plays a dominant role in the cavitation intensity of fluids,which increases continuously between 0.4 and 0.6 MPa.When outlet-pressure continues to increase,the occurrence of cavitation is inhibited by small pressure difference.The turbulence model and mass transfer rate of multihole outflow are analyzed and it is found that the turbulent superposition effect is caused of the fluid and the cavitation intensity is increased by the multihole outflow between 0.4 and 0.6 MPa.

关 键 词：水力空化 多相流 瞬态响应 湍流强度 传质速率 

分 类 号：TK72[动力工程及工程热物理—流体机械及工程]