高速诱导轮离心泵内空化发展可视化实验与数值模拟  

Experiment and Numerical Simulation of Cavitation Evolution in High Speed Centrifugal Pump with Inducer

作　　者：崔宝玲[1] 陈杰[1] 李晓俊[1] 林哲[1] 蔡海兵 韩安达 CUI Baoling;CHEN Jie;LI Xiaojun;LIN Zhe;CAI Haibing;HAN Anda(Key Laboratory of Fluid Transmission Technology of Zhefiang Province Zhejiang Sci- Tech University, Hangzhou 310018, China;Zhejiang Institute of Mechanical and Electrical Engineering Co. , Ltd. , Hangzhou 311305, China;Zhejiang Tiande Pumps Co. , Ltd. , Wenzhoa 325800, China)

机构地区：[1]浙江理工大学浙江省流体传输技术研究重点实验室,杭州310018 [2]浙江省机电设计研究院有限公司,杭州311305 [3]浙江天德泵业有限公司,温州325800

出　　处：《农业机械学报》2018年第4期148-155,共8页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家自然科学基金项目(51579225;51776189);浙江省教育厅一般项目(Y201432052)

摘　　要：为了研究高速诱导轮离心泵内空化发生发展规律,采用高速摄像技术,对离心泵内诱导轮与叶轮流道的空化流动进行可视化研究,并结合CFD数值计算对离心泵内部流场进行模拟分析。结果表明:在空化初生阶段(汽蚀余量为5.0 m),诱导轮叶片前缘出现叶顶泄漏涡空化;在空化发展阶段(汽蚀余量为1.07~5.0 m),流动极为复杂,在诱导轮流道内同时出现叶顶泄漏涡空化、片状空化和云状空化,并且在较低汽蚀余量(汽蚀余量为1.5 m)时,出现不对称空化现象。在空化初生和发展阶段,泵的扬程和效率基本保持不变;在空化恶化阶段(汽蚀余量小于1.07 m),诱导轮流道内基本被空泡堵塞,空泡进入叶轮流道,导致离心泵扬程和效率急剧下降。Cavitation is one of the main causes that jeopardize the steady operation of high speed centrifugal pump. An inducer installed in the upsteam of the impeller is an effective method to improve the cavitation resistance performance of the pump. In order to investigate the evolution process of cavitation in a low-specific high speed centrifugal pump with inducer, the visual experiments of cavitating flow in impeller and inducer passages were carried out by high speed photography. And the internal flow characteristics of the centrifugal pump were analyzed by CFD technology. The experimental results showed that cavitation inception occurred near the blade leading edge of inducer when AH was 5.0 m, which was mainly caused by the tip leakage vortex. In the process of cavitation development （ 1.07 m 〈 △H 〈 5.0 m） , cavitation phenomenon was very complex in which tip leakage vortex cavitation, sheet cavitation and cloud cavitation could be observed in the blade passage of inducer. Also it was found that asymmetric cavitation as one type of cavitation instabilities occurred when net positive suction head was lower （ △H was 1. 5 m） . Both in the periods of cavitation inception and development, the head and efficiency of high speed centrifugal pump with inducer basically remained the original data. The backflow vortex cavitation occurred at the inducer inlet near the shroud in the period of cavitation deterioration （ △H 〈 1. 07 m）. Meanwhile, the bubble generally blocked the whole passage of inducer and spread to the impeller passage that resulted in breakdown of the head and efficiency in high speed centrifugal pump with inducer.

关 键 词：高速离心泵 诱导轮 空化发展 叶顶泄漏涡 可视化实验 

分 类 号：TH311[机械工程—机械制造及自动化]