摘要
为了研究由离心泵内部非定常流动引起的蜗壳流道内的压力脉动这一现象及其特性,针对带有三长三短叶片叶轮的离心泵,采用大涡模拟方法计算包括吸水室、叶轮和蜗壳全流道的流场,获得蜗壳流道压力脉动分布特性,并对其进行了频域和时域分析.结果表明:由于叶片和蜗壳的动静相干作用,蜗壳内的压力脉动比较明显;在设计工况下,叶轮与蜗壳交界面周向上的隔舌处脉动最大;蜗壳内各监测点压力脉动的主频都是长叶片的通过频率,次主频为叶片的通过频率;蜗壳流道不同断面上的压力脉动基本一致,而扩压管内的压力脉动要比螺旋段的更有规律性;设计工况下,蜗壳内压力脉动没有明显的高频成分.
In order to study the characteristics of the pressure fluctuation in volutes caused by unsteady flow in centrifugal pumps,the whole flow field including those in the suction casing,impeller and discharge casing of a centrifugal pump was simulated based on large eddy simulation（ LES） . The impeller of the pump has three long blades and three splitter ones. The pressure fluctuation in the volute was analysed in time and frequency domains. The results show that the obvious fluctuation content depicts the interaction of the flow in impeller and that in volute. At design flow rate,the maximum fluctuation amplitude occurs at the interfaces between the impeller and volute and near the tongue. The dominant frequency of the monitor points in volute is of long blade passing frequency,and the sub-dominant one is of the splitter blade passing content. It can be found that the pressure fluctuation for different sections of volute is basically identical while the pressure fluctuation is more regular in the diffuser part than that in the spiral. There have no significant high-frequency components in volute at design flow rate.
出处
《排灌机械工程学报》
EI
2010年第4期310-314,共5页
Journal of Drainage and Irrigation Machinery Engineering
基金
国家自然科学基金资助项目(50979034)
江苏大学高级人才科研启动基金资助项目(09JDG032)
关键词
离心泵
压力脉动
蜗壳
大涡模拟
时域与频域分析
centrifugal pump
pressure fluctuation
volute
large eddy simulation （ LES）
time-frequency domain analysis
