91制片厂

Numerical methods for accurately computing forces due to drag-coupled particles

In various applications in biology and physics, fluid flows containing small particles appear. In order to simulate such fluids, drag forces between the fluid and particles must be included in the model. However, without
careful treatment, these forces are not accurately computed in standard numerical algorithms for solving the equations of fluid motion. In this talk, two efficient algorithms for obtaining approximations to these forces when large numbers of particles are present will be discussed. One method is based on the
Particle-Particle/Particle-Mesh (PPPM) method, and the other upon the Method of Local Corrections (MLC). Error properties of these methods as indicated from analytical derivation and numerical simulation will be
presented. Initial results show that the MLC-based algorithm, when combined with a special class of finite difference stencils, obtains more rapid convergence then the PPPM algorithm.