离心泵蜗壳内部清水流动测量

Measurements of water flow in centrifugal pump volute

利用ＬＤＶ分别测量了最优和小流量工况下矩形断面蜗壳内３个断面内的清水平均流动．实 验发现，蜗壳内部液体绝对速度的圆周分速度比径向分速度大一个数量级；蜗壳内存在螺旋运动； 蜗壳断面内流体角动量不守恒；无论在最优还是在小流量工况，蜗壳内部流动都是扩压流动；在小 流量工况，扩压更为严重．

The water flow at the position of three cross^sections of a centrifugal pump volute is measured by using two-dimensional laser Doppler velocimeter(LDV) under optimal efficiency and part-loading condi- tions. The results show that the magnitude of tangential component of absolute velocity is larger by one order of magnitude than that of radial component. There are spiral motions in the volute. The conservation of angular momentum of water in volute is destroyed. The water flow is diffused under the conditions of both optimal efficiency and part-loading; especially, the diffusion of flow is extremely large under the part- loading condition.