The floating particle drawdown and dispersion characteristics in a stirred tank with four pitched-blade impellers, fractal impellers, and circle package fractal impellers were studied using computational fluid dynamics (CFD) simulation. The effects of impeller type, impeller speed, impeller spacing, impeller submergence, initial floating particle concentration, and floating particle diameter on the floating particle dispersion quality were investigated. Results showed that the floating particle dispersion degree was improved with an increment in the impeller speed, in term of axial solid concentration profile, solid concentration distribution, and cloud height. The impeller spacing of T2/3 and impeller submergence of T/6 were appropriate for the floating particle drawdown process in this work. Higher initial floating particle concentration was easier to achieve a higher floating particle dispersion degree. Smaller particle diameter resulted in smaller buoyancy and more uniform distribution. Meanwhile, circle package fractal impeller can reduce the power consumption compared with four pitched-blade impeller and fractal impeller at the same impeller speed, and enhance the solid integrated velocity and the level of homogeneity for floating particle dispersion process under the constant power consumption. In addition, the just drawdown speed (N_jd) and correlation equation for N_jd in the three different impeller systems were obtained.

使用计算流体动力学（CFD）模拟研究了具有四个斜叶叶轮，分形叶轮和圆形包装分形叶轮的搅拌釜中的漂浮颗粒降落和分散特性。研究了叶轮类型，叶轮速度，叶轮间距，叶轮浸没率，初始漂浮颗粒浓度和漂浮颗粒直径对漂浮颗粒分散质量的影响。结果表明，在轴向固体浓度分布，固体浓度分布和云高方面，随着叶轮速度的增加，漂浮颗粒的分散度得到改善。的叶轮间距Ť 2/3和叶轮浸没Ť/ 6适用于这项工作中的浮点沉降过程。较高的初始漂浮颗粒浓度更容易实现较高的漂浮颗粒分散度。较小的粒径导致较小的浮力和更均匀的分布。同时，在相同的叶轮速度下，圆形包装分形叶轮与四个变桨叶形叶轮和分形叶轮相比可降低功率消耗，并在恒定功率下提高浮体分散过程的固体整体速度和均匀性。另外，刚刚垂伸速度（Ñ _JD）和相关性方程式为Ñ _JD在三个不同的叶轮系统获得。