多相混输泵动叶轮流道内气相分布规律研究

Study on Gas Distribution in the Flow Passage of Multiphase Pump Impeller

为了揭示多相混输泵动叶轮流道内含气率的分布规律,基于标准k-ε湍流模型,以空气和纯水作为两相介质,采用Fluent软件在进口含气率为30%的工况下对泵内两相流态进行模拟,分析不同叶高下的气相分布特性。研究表明:在首级动叶轮叶片压力面轮毂附近的气相体积分数最大,而在次级和末级动叶轮叶片压力面上的气相体积分数基本相同;在不同压缩级动叶轮0.5倍叶高处,从动叶轮进口到出口,首级动叶轮叶片吸力面上的气相体积分数比次级和末级大;从轮毂到轮缘首级动叶轮叶片压力面上的气相体积分数与次级和末级动叶轮叶片压力面上的气相体积分数的差值逐渐减小,而在吸力面却逐渐增加。本文的研究结果为提高多相混输泵输送效率及运行稳定性提供了参考。

To reveal the gas distribution in the multiphase pump impeller passage,based on the standard k-εturbulence,the air and pure water were used as two-phase media,and the Fluent software was employed to simulate the two-phase flow state under the inlet gas volume fraction of 30%,and the gas distribution characteristics under different blade spans were analyzed.Results show that the gas volume fraction near the hub of first stage impeller pressure side is the largest.However,the gas volume fraction on the second and last stage impeller pressure side is almost the same.From the impeller inlet to outlet at 0.5 span in difference compression stage,the gas volume fraction on the first stage impeller suction side is larger than that of the second and last stage impeller.The difference of the gas volume fraction on the pressure side from the hub to the shroud between the first stage impeller and second or last stage impeller is gradually decreased.However,the suction side is gradually increased.The results provide a reference for improving the efficiency and stability of a multiphase pump.