离心泵内变工况流动特性的数值研究

Numerical Simulation of Non- Uniform Flow in Centrifugal Pump at Design and Off- Design Conditions

通过Fluent软件对某单级单吸涡壳离心泵内流动进行了变工况定常数值模拟,数值模拟值与实验值吻合良好。在此基础上分析流道内相对速度分布及总压分布情况。并探讨了轴向涡随流量的变化特征及叶轮与涡舌相对位置变化对流动的影响。数值模拟结果显示,随着流量的增加流道出口相对速度增加,总压降低,流道内轴向涡有所减小。靠近涡舌流道的流量较大,而远离涡舌的则较小。这种流动状态沿叶轮周向分布不均匀现象是普遍存在的,且在非设计工况下表现得更明显。

This paper shows the capability of a numerical simulation with the commercial software FLUENT in capturing the characteristics in a Centrifugal Pump at both design and off-design condi- tions. The numerical results are compared with the experimental results and show a good agreement. Based on the correct numerical results, detailed analysis was applied to the distribution of relative velocity and total pressure in one of the centrifugal impeller channels. Furthermore, with the increas- ing of relative velocity, the total pressure and axial vortex of a channel near the vortex tongue is much bigger than the others. And the non-uniform distribution of flow characteristics along the cir- cumferential direction is common in the off-design conditions.