Numerical study on flow stall and kinetic energy conversion of low-specific-speed centrifugal pump

Stall is a common phenomenon in centrifugal pumps under low-flow conditions; it has significant impact on fatigue and can even damage mechanical structural components. Computational fluid dynamics was used to perform high-precision numerical calculations describe multiple operating conditions the computational domain. The accuracy of these simulations verified by comparing results with single-flow channel flow patterns captured time-resolved particle image velocimetry external characteristics pump. On this basis, unsteady spatiotemporal evolution vortex structure stall kinetic energy conversion relationship were determined. rotating condition relative motion impeller circumferential direction between channels, characteristic propagation frequency fcs = 0.71 Hz. For stationary conditions, critical greater dissipation compared deep condition, differences being more than three times larger at blade leading edge, where formed.