基于CFD-DPM的离心泵内颗粒性质对泵性能与磨损的影响

Influence of Particle Properties on the Performance and Wear of Centrifugal Pumps Based on CFD-DPM

为揭示离心泵在输送固液两相流时颗粒密度和粒径对泵性能和磨损的影响,采用Realizable k-ε湍流模型(液相)和DPM离散相模型,对模型泵内固液两相流动进行定常数值模拟,研究固液两相流场中颗粒的运动轨迹以及磨损规律。结果表明:随着颗粒密度和粒径的增大,模型泵的扬程和效率均下降;密度、粒径越大的颗粒,其运动轨迹越易偏向叶片工作面;随着颗粒密度的增加,叶片工作面以及蜗壳内的磨损程度加剧,但是叶片背面的磨损减轻,颗粒相应地在叶片工作面和蜗壳外壁边缘聚集;随着颗粒粒径的增大,蜗壳整体磨损程度加重,其中蜗壳的隔舌区域、Ⅱ区域和Ⅵ区域磨损程度最严重;叶片整体磨损程度逐渐降低,且叶片工作面磨损程度大于叶片背面。

In order to reveal the influence of particle density and particle size on the performance and wear of centrifugal pump in solid-liquid two-phase flow,the Realizable k-εturbulence model(liquid phase)and the DPM discrete phase model were employed to conduct steady-state numerical simulation of the solid-liquid two-phase flow within the model pump.The motion trajectory of particles and the wear mechanism in the solid-liquid two-phase flow field were studied.The results show that both of head and ef-ficiency of the present pump decrease with the increase of particle density and particle size.The larger of the particle density and diameter,the closer of the particles to the blade pressure side.With the increase of particle density,wear on the blade pressure side and volute increases,whereas wear on the blade suction side decreases.According to this,particles are mainly concentrated near the blade pressure side and volute wall surface.With the increase of particle diameter,wear on the volute surface increases and is more signi-ficant at the volute tongue,II and VI regions.However,wear on the blade surface shows opponent tend-ency,and wear on blade pressure side still be stronger than blade suction side.