离心泵内部非定常空化流动特征的数值分析  

Numerical analysis of unsteady cavitating flow characteristic in centrifugal pump

作　　者：杨敏官[1] 孙鑫恺[1] 高波[1] 邵腾[1] 

机构地区：[1]江苏大学能源与动力工程学院,江苏镇江212013

出　　处：《江苏大学学报（自然科学版）》2012年第4期408-413,共6页Journal of Jiangsu University：Natural Science Edition

基　　金：国家自然科学基金资助项目(50776040);江苏高校优势学科建设工程项目;江苏省高校自然科学研究项目(11KJB470003)

摘　　要：运用完整空化模型和混合流体两相流模型,对比转数为130的离心泵流道内部的空化流动进行了定常及非定常的数值模拟.预测了叶轮流道内空化发生部位和发展程度,对蜗壳隔舌附近处流场的压力场进行了监测,得到了压力脉动的变化规律.结果表明:空化初生位于叶片背面进口边附近处,随着进口压力的降低,空泡分布区域及空泡体积分数不断扩大,当空化严重时,叶片工作面上会有空泡聚集;在叶轮的1个旋转周期中,单个叶片表面上的空化发展程度随叶轮与蜗壳相对位置的改变而发生规律性的变化;压力脉动频率存在明显离散特性,叶片通过频率下的脉动幅值较大;随着空化程度的发展,空化流动诱导泵流道内压力脉动幅值不断增加,并且两者存在相互对应关系.Based on full cavitation model and mixed two-phase flow model,the steady and unsteady cavitating flow-passages in centrifugal pump with specific speed of 130 were numerically simulated.The region and the degree of cavitation in the centrifugal pump flow-passage were predicted.The characteristics of pressure fluctuation was achieved by monitoring the pressure fields around the volute tongue.The si-mulation results indicate that the cavitation generates at the suction side of blades near leading edge.The region of vapor extends and the volume fraction of vapor increases with the decreasing of total inlet pressure.The vapor appears on the pressure side of blades when the cavitation is deteriorated.The cavitation degree on each blade changes periodically with the change of relative position between impeller and volute.The frequency of pressure fluctuation shows obvious discrete characteristic with high blade passing frequency amplitude.With the development of cavitation degree,the pressure fluctuation amplitude induced by cavitating flow in flow-passage is increased with a corresponding relationship.

关 键 词：离心泵 空化 非定常空化流动 压力脉动 频域分析 

分 类 号：TH311[机械工程—机械制造及自动化]