关于颗粒惯性聚集现象数值算法的分析与研究

Analysis and study on numerical algorithm of inertial focus of particles

为深化对颗粒惯性聚集现象及原理的研究,通过CFD数值模拟技术针对球形颗粒在微通道内的聚集运动建立了相应模型,以不同的数值算法进行模拟分析。通过对比分析不同条件下两种模型,即"相对运动模型"和"六自由度模型"的数值计算结果与实验数据的适配情况,分析两者的精准度与适用性,为颗粒惯性聚集现象的模拟研究提供指导。研究结果表明:"相对运动模型"适用于颗粒粒径或雷诺数较小的情况,可以快速得到颗粒惯性升力的空间分布,进而确定其聚集位置。"六自由度模型"以大量的计算时间为支撑,其计算结果在各种工况下均具有较高的精确度;能描述颗粒惯性聚集运动的轨迹;能够跟踪测量聚集过程中,颗粒在各个位置的运动参数和受力情况。

In order to deepen the study of the phenomenon and principle of the inertial focus of particles,CFD numerical simulation technology was used to establish different kinds of micro-channel for the inertial focus of spherical particles,and perform the simulation analysis in different numerical methods. Through the comparative analysis of experimental data and the numerical calculation results of the two models,namely relative motion model and six degree of freedom model,under different conditions,the accuracy and applicability of two kinds of model were analyzed,and guidance for the simulation studies of the inertial focus phenomenon of particles were provided. The results showed that the relative motion model was suitable for the condition of small size of particles and the channel flow with low Reynolds number,and could get the space distribution of the inertial lift of particles quickly,and then determined the focus position; The six degree of freedom model needed a lot of time to complete simulation calculation,and the calculation results had a high accuracy in various conditions; The six degree of freedom model could describe movement trajectory of inertial focus of particles,and collect motion parameters and force condition of particle in each position in the process of focusing.