离心泵叶轮内二维PIV非定常流动测量

2-D PIV Measurements of Unsteady Flow Field inside the Rotating Impeller of Centrifugal Pump

采用二维PIV对离心泵蜗舌附近旋转叶轮内的流场进行了测量,获得了5个不同相位的二维相对速度场。结果显示:在流量Q/Qbep=0.52时,叶轮内压力面存在逆时针方向的回流,叶片在靠近蜗舌时,吸力面存在顺时针方向的回流。在流量Q/Qbep=1.0时,叶轮出口存在射流/尾迹现象。研究表明:小流量工况下,蜗舌对叶轮内的相对速度场有显著影响,而在最优工况下影响较弱。

The flow fields in a rotating impeller,near the volute tongue of a centrifugal pump,were measured by the 2-D PIV technique.At the flow rate of Q/Qbep=0.52,a counter clockwise recirculation flow existed on the blade pressure-side,when the blade was close to the volute tongue,a clockwise recirculation flow occurred on the blade suction-side.At the flow rate of Q/Qbep=1.0,a jet/wake flow existed at the exit of the impeller.The results show that the effects of the volute tongue on the relative velocity distribution are more significant at the low flow rate condition than at the best efficiency point.