离心泵蜗壳内流动的高速摄影测试

Measure Fluid Flowing in Volute of Centrifugal Pump

低比速离心泵的 Q—H性能曲线在小流量区容易出现右上升段,这主要与泵内流动有关。用示踪粒子配合高速摄影法测试了50-32-125单级单吸离心泵蜗壳内隔舌附近的流场。流场分析证实了蜗壳内隔舌附近的旋涡(同流)是产生右上升 Q—H性能曲线的重要原因之一。对3种不同叶片数的叶轮流场的比较研究证实,叶片数少时,性能曲线的右上升段趋于消失,隔舌附近蜗壳流道中的旋涡减弱。

The right raising section occurs easily in Q-H curve at small flowrate area in a low specific speed centrifugal pump,which depends on the fluid flowing in the pump principlely.The flowing field nearby the cut- tongue in a volute of the single stage and end suction centrifugal pump of type 50-32-125 is measured by means of tracing particles with smear photography camera.Analysis on the fluid flowing field verifies that the eddy nearby the cut-tongue in a volute is one of the important reasons causing the right raising section in Q-H curve.Three types of flowing fields of different blade numbers are measured and compared.The results show that the right raising section of Q-H curve tends to disappear when reducing the blade numbers,at the same time the eddy nearby cut-tongue can be reduced.