摘要
流场压力脉动是影响大型轴流泵运行稳定性的关键因素,本文采用时间相关的瞬态流分析理论及大涡模拟方法研究轴流泵内部非定常流动,得到了不同工况下泵内水压力脉动结果。通过与实测扬程和功率对比,证明本文所提出的方法可较准确地反映泵的流动特征。研究表明,轴流泵内最大压力脉动发生在叶轮进口前,压力脉动频率主要受叶轮转频控制;在叶轮进口与出口处,从轮毂到轮缘压力脉动逐渐增大,而在导叶中间及导叶出口处,结果正好相反。偏离最优工况越远,脉动的相对振幅越大,在60%流量工况下泵内压力脉动约为最优工况的2倍。
The pressure fluctuation in large scale axial-flow pump is a major factor affecting the operation stability. The transient fluid dynamics and large eddy simulation （LES） method are applied to simulate the unsteady flow in axial-flow pump. The pressure fluctuations under various operation conditions are obtained. The results show that the maximum amplitude of pressure fluctuation takes place at the inlet of impeller. The frequency of pressure fluctuation is dominated by the rotation speed of impeller. Both at the inlet and outlet of impeller the fluctuation amplitude increases from hub to tip, but it decreases at the middle area and outlet of guide-vanes. The fluctuation becomes stronger as the flow rate is far from optimum operation point. The relative fluctuation at 60% optimum flow rate is about twice the value at optimum flow rate.
出处
《水利学报》
EI
CSCD
北大核心
2007年第8期1003-1009,共7页
Journal of Hydraulic Engineering
基金
北京市自然科学基金项目(3071002)
国家自然科学基金项目(9051007)
教育部新世纪优秀人才支持计划项目(NCET-04-0133)
关键词
轴流泵
不稳定流场
压力脉动
大涡模拟
axial-flow pump
unsteady flow field
pressure fluctuation
large eddy simulation method
