Research Of Solid-liquid Two-phase Centrifugal Pump Wear Erosion

Due to the high sediment concentration characteristics in the Yellow River, the silt accumulation in irrigation channel is serious, and the wear erosion of mechanical equipment of pumping station is prominent. So this article takes the adovantage of the Eularian-Lagrangian multiphase model, and the three- dimensional simulation of centrifugal pump was performed for the solid-liquid flow. The flow field feature and the change of outside characteristics were analyzed under different flow conditions with various solid volume concentration for researching the influence of solid volume concentration brings to inner flow and wear erosion.The main works and research of the study papers are as follows:1)Because some deviations exist in the traditional solid phase discretization computing methoc, Some relevant empirical formulas and the Alhert erosion model combined with the result of Mclaury wear test are introduced to modify it, then a simple bend simulation takes this modified method, and the calculation results is verified with experimental data. It turned out that this numerical simulation method is actual and reliable.2)The numerical calculation of a centrifugal pump is taken respectively under water and solid-liquid conditions. The results show that the lift and efficiency curve of centrifugal pump decreases with solid volume concentration magnify; compared with water conditions the solid volume concentration has strong influence on flow field pressure distribution and flow streamlines. With the solid volume concentration magnify, the inner flow field pressure grow up while impeller blade pressure difference continues reducing, and the impeller control ability become weak; compared to water conditions the pressure fluctuation amplitude of the centrifugal pump running at solid-liquid flow is enhanced by the presence of solid particles at small flow conditions, which means that the pump vibration is aggravated in some extent.While the solid particle play an opposite role in large flow conditions.3)Though the research of flow components wear erosion, it can be found that there is a strong relationship between solid volume concentration and wear erosion. With the increase of solid volume concentration some various sizes of second flow appearing at impeller internal flow internal flow field at small flow conditions. Beside with decrease of mass flow the second flow phenomenon gradually extend to inlet and the shroud wear erosion is triggered at the same solid volume concentration.