中文摘要：

在两相混合模型的基础上,加载群体平衡模型,采用分组法对离心泵内部盐析两相流场进行数值模拟,得到了3种不同工况各尺寸盐析晶体颗粒的分布特性.预测了离心泵内液固两相流场中晶体颗粒的分布规律,与本项目前期试验结果总体趋势比较吻合,验证了群体平衡模型用于模拟伴有盐析现象两相流动的可行性.计算结果表明：叶片流道内,从压力面至吸力面颗粒平均粒径逐渐减小,流量增加,粒径较大颗粒向压力面聚集现象更加显著;涡室内颗粒平均粒径呈现的分布特征：主流区最小,内壁附近较大,离叶轮较远的壁面拐角处最大.此外,受相间传质及颗粒微观行为影响,不同粒径颗粒的组分数分布差异较大,从叶轮进口至出口,大粒径颗粒组分数逐渐增高,而中、小粒径颗粒的组分数分布趋势与之正好相反.

英文摘要：

A population balance model has been incorporated with the mixture multiphase model based on Fluent code to simulate the two-phase flow with salt-out behaviors in a centrifugal pump at three different operating conditions.The computational results of particle size distribution generally consist with the experimental ones,which proves the feasibility of the numerical metheds.It is found that the particle mean diameter reduces gradually from the pressure side to the suction side in a single flow passage.Aggregation of large-size particles near the pressure side gets remarkable with the increase of flow rate.In the volute,the smallest average particle size appears in the middle flow passage.Near the inner wall,average particle size is relatively large.Largest average particle size emerges at the corner of the wall far away from the impeller.Furthermore,the difference of class fraction distributions between particles of various sizes is obvious under the influence of the mass transfer and microscopic particle behaviors.The class fraction of large-size particles increases gradually from blade inlet to the blade outlet,but for the middle and small size particles,distribution trend is just the opposite.