沙粒参数对离心泵内部流动特性影响OA

To investigate the influence of sand parameters on the flow characteristics within a centrifugal pump,numerical simulations were conducted using the Eulerian multiphase flow model un-der solid-liquid two-phase flow conditions.A filtered turbulence model was incorporated to refine the local time-homogenized turbulence closure.The effects of sand volume fraction and particle size on the solid-liquid flow field and associated hydraulic losses were systematically examined.The results indicate that as the sand concentration increases,the head and efficiency of the centrifugal pump de-crease by an average of 3.7％and 4.5％,respectively.The region of high sand volume fraction near the pressure side of the blade expands,and particle accumulation becomes more pronounced in the middle and lower sections of the flow passage.Consequently,flow losses intensify along the pressure side of the blade and along the front and side regions of the volute.In contrast,an increase in sand particle size leads to an average reduction in pump head and efficiency of 2.5％and 3.7％,respectively.The distribution of sand particles within the impeller becomes more uniform,with a reduction in localized high-volume fraction zones.Although the radial distribution pattern of particles remains largely un-changed,the particle velocity tends to decrease.Additionally,flow losses along the blade pressure side and the volute are noticeably reduced.These findings provide theoretical support for the hydraulic de-sign of centrifugal pumps handling solid-liquid two-phase flows.