空化过程对半开式叶轮离心泵泵腔压力脉动的影响  

Effect of Cavitation Process on Pressure Pulsation in Pump Chamber of Half-open Impeller Centrifugal Pump

作　　者：梁武科[1] 张琳姗 董玮 朱金瑞 艾改改 刘云琦 LIANG Wuke;ZHANG Linshan;DONG Wei;ZHU Jinrui;AI Gaigai;LIU Yunqi(Institute of Water Resources and Hydrologic Engineering,Xian University of Technology,Xi'an,710048,China;College of Water Resources and Architectural Engineering,Northwest A&F University,Yangling 712100,China)

机构地区：[1]西安理工大学水利水电学院,西安710048 [2]西北农林科技大学水利与建筑工程学院,陕西杨凌712100

出　　处：《大电机技术》2022年第5期51-58,共8页Large Electric Machine and Hydraulic Turbine

基　　金：国家自然科学基金资助项目(52009114);陕西省水利科技计划项目经费资助(2019slkj-10,2019slkj-15);中国博士后科学基金面上资助项目(2021M692660);水力发电设备国家重点实验室开放课题(SKLHE-ORF-202103)。

摘　　要：为了研究空化过程对泵腔内压力脉动的影响,本文以半开式离心泵作为研究对象,基于连续性方程、雷诺时均N-S方程和标准k-ε模型,对设计工况下的离心泵进行了全流道空化模拟。结果表明,空化状态下,靠近隔舌处叶轮流道空泡体积最大,发展最为迅速,随着空化程度的加深,叶轮出口流动不均匀性增强,伴随与蜗壳隔舌动静干涉作用导致泵腔内部压力进一步下降。空化的发展导致泵腔内各监测点压力脉动幅值增大,规律性变差。在相同的空化余量下,压力脉动的幅值与泵腔内监测点的半径成正比关系,同一监测点压力脉动幅值随叶轮旋转呈周期性变化,并且沿叶轮旋转方向逐渐减小。泵腔内振动主频集中在叶频及其倍频处,并且随着频率的增加逐渐衰减,衰减的过程极为迅速。该研究对今后离心泵的结构优化设计和工程实践提供一定的参考依据。In order to study the influence of the cavitation process on the pressure pulsation in the pump chamber of the half-open impeller centrifugal pump,this study,based on the continuity equation,the momentum equation and the standard k-ε model coupled with the homogenous cavitation model with full flow path under design conditions is carried out.The results show that in the state of cavitation,the cavitation volume of the impeller flow channel near the tongue is the largest and develops most rapidly,as the degree of cavitation deepens,the unevenness of the flow at the outlet of the impeller increases,and the pressure in the pump chamber is further reduced due to the static and dynamic interference with the volute tongue.The development of cavitation causes the pressure pulsation amplitude of each monitoring point in the pump cavity to increase,and the regu larity becomes worse.Under the same cavitation margin,the pressure pu lsation amplitude of the same monitoring point changes periodically with the rotation of the impeller,and gradually decreases along the direction of rotation of the impeller.The amplitude of the pressure pulsation is proportional to the radius of the pump cavity.The most violent vibration is mainly concentrated at the leaf frequency and double frequency,and gradually attenuates as the frequency increases,and the attenuation process is extremely rapid.This research provides a certain reference basis for the structural optimization design and engineering practice of centrifugal pumps in the future.

关 键 词：离心泵 泵腔 临界空化 严重空化 压力脉动 

分 类 号：TH311[机械工程—机械制造及自动化]