旋转型分离器流场中粒子运动的数值解析

Numerical analysis of particle motion in flow field of revolving-type solid-liquid separator

作为固液分离器的基础研究,应用龙格-库塔法对进入旋转态液体中的固体粒子由运动开始到被分离完成的全过程进行了数值计算。动力学模型中除考虑了重力、浮力、流体粘性力外,还考虑了假想质量力、Basst力、Sffm an扬力以及压力梯度力等多种力的作用。在实验装置中与数值计算参数相同的条件下进行了可视化实验研究。计算结果发现,在运动开始阶段,粒子的粒径越小,加速度越大,很快进入运动平衡状态,相反粒子粒径越大,加速度越小。运动的第2阶段,直径大的粒子仍在加速运动,因此不同直径的粒子运动之间存在一个运动加速度、速度及位移逆转现象。数值解析结果与可视化实验结果进行了比较,证明了数学模型与计算结果的正确性。

To be the fundamental study of solid-liquid separator, Runge-Kutta method was applied to calculating the whole procedure from starting time of movement to the separation ending of a solid particle which was thrown into the rotating cylindrical fluid. In mathematical model, besides gravity, buoyancy and fluid viscous force, the forces such as artifact body force, Basst force, Sffman lifting force and pressure gradient force were considered. The visualization experiment was carried out in the experiment set at the same condition of parameter calculation. The numerical calculation results show that at the beginning of motion, the smaller the diameter of the particle becomes, the larger the particle motion acceleration is, thus quickly entering the motional balanced state; on the contray, the larger the diameter of the particle becomes, the smaller the particle motion acceleration is. In the second stage, the particle in large diameter is also accelerated; the phenomenon of different motion acceleration, velocity and displacement reversion exists among the particles in different sizes. The comparison of testing and calculation result proves the correctness of mathematical model and numerical calculation.