非球形颗粒两相流的数值模拟研究进展

非球形颗粒两相流是多相流的重要研究方向之一, 常见于自然界及工业生产过程中. 不同于球形颗粒, 由于非球形颗粒形状的各向异性, 除了颗粒平动行为, 还需要考虑颗粒的转动与取向行为, 颗粒的取向与转动行为会影响颗粒所受的力和力矩. 为了准确模拟非球形颗粒的运动行为, 目前非球形颗粒两相流的数值模拟研究主要基于欧拉?拉格朗日的求解框架展开, 常见的非球形颗粒两相流数值模拟方法主要包括点颗粒法与全分辨颗粒法. 本文将对这两类方法进行介绍, 同时会全面介绍非球形颗粒两相流研究的基础理论模型, 并系统总结非球形颗粒在简单基本流和复杂湍流中的研究进展, 包括对于非球形颗粒在湍流中的取向与转动行为机理, 以及颗粒对湍流减阻调制作用的研究. 最后, 本文提出了非球形颗粒两相流研究存在的问题及未来研究方向. 

Numerical study of non-spherical particle-laden flows

Non-spherical particle-laden flows are commonly seen and important in nature and industrial processes. The particle's rotational and orientational behaviors could affect the forces and torques acting on the particle from ambient fluid flow. To accurately capture the motion of non-spherical particles, especially for angular particle dynamics, most numerical studies of non-spherical particle-laden flows are carried out in the Euler-Lagrange frame. There are two most popular numerical approaches: the point-particle method and the particle-resolved method. This paper comprehensively and systematically summarizes these methods and significant recent findings about non-spherical particles in simple and turbulent flows. The mechanism of particle orientation and rotation by suspended non-spherical particles, as well as the modulation effect of particles on turbulent drag reduction, are discussed. Furthermore, the key and unsolved problems of non-spherical particle-laden flows for future study are proposed at the end of the paper.