流量对离心泵蜗壳内压力及速度分布的影响

Influence of flowrate on pressure and velocity distributions in a centrifugal volute.

用等速度系数法设计的矩形断面离心泵蜗壳内,在蜗壳侧面沿圆周方向试验测量了各种流量下中轴垂面上压力的分布,并通过激光多普勒测速仪测量了不同流量下蜗壳内的速度场。通过分析压力测量结果,指出离心泵在小流量工况时,蜗壳内沿液流方向的压力分布呈现出由大变小再变大的分布规律;中高流量工况时,蜗壳内压力分布的“降速扩压”特征明显。弄清这种分布规律对提高离心泵的性能及蜗壳优化设计具有指导意义。

On the test bed for a centrifugal pump, the pressure distribution along the outside of the volute, whose sections are rectangle and designed by constant velocity method, is measured. The velocity fields of the volute with different flowrates is measured by LDV. By analyzing the result from the pressure measurement, it is indicated that, when the centrifugal pump works with a flowrate out of the design flowrate range, the curve of the pressure distribution in the volute willchange with the flowrate and influence the velocity distribution in the volute thereby. Making clear the pressure distribution pattern will give guide to improving the performance of the centrifugal pump and to the optimization of the centrifugal volute.