不同空化余量下高比转速轴流泵叶轮区压力脉动特性  

Pressure pulsation characteristics of impeller area of high specific rotating speed axial flow pump under different cavitation margins

作　　者：孙壮壮 张家敏 汤方平 吕宁 王梦成 陈松山 SUN Zhuangzhuang;ZHANG Jiamin;TANG Fangping;L Ning;WANG Mengcheng;CHEN Songshan(School of Mechanical Engineering,Yangzhou Polytechnic College,Yangzhou 225100,China;College of Hydraulic Science and Engineering,Yangzhou University,Yangzhou 225100,China;College of Electrical and Energy Power Engineering,Yangzhou University,Yangzhou 225100,China)

机构地区：[1]扬州市职业大学机械工程学院,江苏扬州225100 [2]扬州大学水利与科学工程学院,江苏扬州225100 [3]扬州大学电气与能源动力工程学院,江苏扬州225100

出　　处：《振动与冲击》2024年第21期80-88,共9页Journal of Vibration and Shock

基　　金：国家自然科学基金项目(51376155);江苏省自然科学基金(SBK2023042972);中国博士后科学基金(2023M741499);江苏省高效节能大型轴流泵站工程研究中心开放课题(ECHEAP022);扬州市“绿杨金凤”资助项目(2023);扬州市职业大学校级科研项目(2023XJ02)。

摘　　要：为了研究空化对高比转速轴流泵叶轮区压力脉动的影响,以某比转速约1100的轴流泵为对象,通过压力脉动测量、高速摄影技术,分析了不同空化余量下叶轮区的压力脉动特性。研究结果表明:设计工况下空化自叶片前缘处产生,以叶顶泄漏涡(tip leakage vortex,TLV)空化为主,大流量工况下空化自叶片进口边工作面产生,以片空化为主。随着空化余量的降低,空泡引起的流动阻塞及低压区范围扩大对叶轮区监测点压力脉动影响逐渐加大,叶片前缘监测点P_(1)及叶片尾缘监测点P_(3)的压力脉动变化主要表现为低频脉动成分增加,波形中高阶谐波成分降低;而叶轮中部监测点P_(2)受空泡运动扰动的影响,波形中高阶谐波分量上升,高频脉动成分增加。除设计流量和大流量工况下监测点P_(1)压力脉动强度呈现整体下降趋势,各监测点压力脉动强度分布中通常存在一个局部上升点,空化的产生在某个空化余量范围内导致叶轮区的脉动强度增大。该研究分析了不同空化余量下叶轮区压力脉动特性,结果可为轴流泵的安全稳定运行提供参考。Here,to study effects of cavitation on pressure pulsation in impeller area of high specific speed axial flow pump,a axial flow pump with a specific speed of about 1100 was taken as the object,with pressure pulsation measurement and high-speed photography technology,pressure pulsation characteristics of impeller area under different cavitation margins were analyzed.The study results showed that under design flow condition,cavitation is generated at blade leading edge,and dominated by tip leakage vortex(TLV)cavitation;under large flow conditions,cavitation is generated at working surface of blade inlet side,and dominated by sheet cavitation;with decrease in cavitation margin,effects of flow blockage caused by cavitation and low-pressure area expansion on pressure pulsation at monitoring points of impeller area gradually increase;pressure pulsation changes at leading edge monitoring point P 1 and blade trailing edge monitoring point P 3 mainly exhibit increase in low-frequency pulsation components and decrease in high-order harmonic components in waveform;monitoring point P 2 in middle of impeller is affected by disturbance of bubble motion to cause increase in high-order harmonic components and high-frequency pulsation components in waveform;except for pressure pulsation intensity at monitoring point P 1 exhibits the overall decreasing trend under design flow and large flow conditions,there is usually a local rising point in pressure pulsation intensity distribution of each monitoring point;generation of cavitation causes increase in pressure pulsation intensity of impeller area within a certain range of cavitation margin;pressure pulsation characteristics of impeller region under different cavitation margins analyzed here can provide a reference for safe and stable operation of axial flow pumps.

关 键 词：轴流泵 水力机械 压力脉动 空化 

分 类 号：TH313[机械工程—机械制造及自动化]