Abstract:To study the effect of inflow conditions on an axial flow pump, two different types of non-uniform inlet velocity distributions were established. By comparing with uniform inflow conditions, the effects of the non-uniform inflow conditions on pump performance, radial forces and pressure fluctuations were achieved by numerical simulations. Comparison of numerical simulation results and experimental values under uniform inflow verifies the accuracy of the numerical model. A comparative analysis of the effects on pump head, efficiency and radial force curves was performed under 0.7Q-1.2Q conditions. The variation of the axial flow pump performance and radial loads with the non-uniformity of the inlet velocity was obtained. Finally, based on the unsteady simulation, pressure fluctuations at impeller inlet, impeller outlet and guide vane exit at design condition were monitored, and the effects of two non-uniform inflows on pressure pulsations at three typical positions were achieved. The results show that by controlling the inflow situation, the hydrodynamic performance with non-uniform inflow is better than that with uniform inflow distribution.
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