叶顶间隙对潜水轴流泵压力脉动的影响研究
Influence of blade tip clearance on pressure fluctuation of submerged axial flow pump
郑文贤 1王开杰 1汪程鹏 2王生辉 2周冲 1李嘉成1
作者信息
- 1. 长安大学 道路施工技术与装备教育部重点实验室,陕西 西安 710064
- 2. 自然资源部 天津海水淡化与综合利用研究所,天津 300192
- 折叠
摘要
轴流泵的叶顶间隙泄漏是引起涡动干扰和压力脉动的关键因素,不同叶顶间隙下机组受到的激振力和压力冲击差异显著.本文以350ZQ-125 型高比转速立式潜水轴流泵为研究对象,采用RNG k-ε湍流模型,对 6 个不同叶顶间隙叶轮模型在设计流量工况下轴流泵三个关键部件流道内压力脉动进行计算.结果显示,不考虑叶顶间隙时,轴流泵内部压力脉动主要由动静干涉引起;考虑叶顶间隙时,泵内压力脉动受间隙泄漏的影响,进水喇叭和导叶流道内呈现为低频脉动,脉动幅值随着间隙的增加逐渐降低.叶轮流道内的受叶片扰动脉动主频为3 fn,且脉动幅值变化不明显.合适的叶顶间隙尺寸可以降低叶轮进口和导叶出口的压力脉动.
Abstract
The blade tip clearance of the axial flow pump is the key factor that causes vortex interference and pressure fluctu-ation,and the excitation force and pressure impact received by the unit under different blade tip clearance are significantly different.In this paper,350ZQ-125 vertical submerged axial flow pump with high specific speed is taken as the research ob-ject,and RNG k-ε turbulence model is adopted to calculate the pressure fluctuation in the three key parts of the axial flow pump with different blade tip clearance under the designed flow conditions.The results show that the pressure fluctuation in the axial flow pump is mainly caused by the dynamic and static interference when the blade tip clearance is not considered.When the blade tip clearance is considered,the pressure fluctuation in the pump is influenced by the clearance leakage,low-frequency fluctuation appears in the inlet horn and the guide vane flow channel,and the fluctuation amplitude gradually de-creases with the increase of the clearance.The dominant frequency of the fluctuation in the impeller flow channel is 3 fn,with insignificant fluctuation amplitude variation.Proper blade tip clearance can reduce the pressure fluctuation at the impeller in-let and the guide vane outlet.
关键词
轴流泵/叶顶间隙/数值计算/压力脉动Key words
axial flow pump/blade tip clearance/numerical calculation/pressure fluctuation引用本文复制引用
出版年
2024
NETL
NSTL
万方数据