Abstract:Cavitation characteristics induced by inlet backflow were studied in a centrifugal pump of type IS65-60-160.Numerical simulation were carried out firstly on the basis of standard k-ε model to analyze the independence of the grid number through three different kinds of CFD software such as CFX,Fluent and PumpLinx.Secondly,the open performance experiments were carried out to verify the accuracy of CFD software.Finally,the one with the was chose for the simulation of backflow vortex cavitation and pressure fluctuation.The results show that the hydraulic performance at low flow rate using the CFX code is more close to the experiment data as compared to the other two kinds of CFD software.The displacement effect of backflow increased the cavitation intensity around the mainstream region.Backflow vortex cavitation occurred at free state,and then developed attached to the blade.It shows a slight increase before head coefficient dropped sharply due to backflow vortex cavitation erosion and bubble collapse.The frequency of 9.7 Hz was found to be closely linked to the backflow vortex cavitation.
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