颗粒沉降运动的虚拟区域法直接数值模拟

文采用基于四边形网格的分布式拉格朗日乘子／虚拟区域方法(DLM／FD method)对二维方槽内775个圆形颗粒在流体中的沉降过程进行了直接数值模拟。得到了颗粒流沉降过程中流体和颗粒速度和涡量分布、流场压力分布等流动细节,展示了颗粒在沉降过程中由于相间的相互作用以及颗粒间的作用,使得颗粒流在流场内形成大小不一的旋流区,颗粒回旋着沉降,同时颗粒的尾涡影响附近颗粒的运动．本文的结果说明分布式拉格朗日乘子／虚拟区域方法对模拟存在很多颗粒的悬浮体流动是可行的。

DIRECT NUMERICAL SIMULATION OF SEDIMENTATION OF PARTICLES WITH FICTITIOUS DOMAIN METHOD

This investigation is performed to see the sedimentation of 775 particles in 2-dimention rectangular region. The distributed Lagrange multiplier/fictitious domain method was applied to do the direct numerical simulation. The results include the velocity of the particle and fluid, pressure and the wake structure of the particulate flow. The data suggested that these particles did not sediment in a direct way and their wake affected other particle's moving. It is concluded that the fictitious method is a proper way to simulate particulate flow within many particles.