A distributed Lagrange multiplier/fictitious domain method for the simulation of flow around moving rigid bodies: application to particulate flow

In this article we discuss the application of a Lagrange multiplier based f ictitious domain method to the numerical simulation of incompressible visco us flow modeled by the Navier-Stokes equations around moving rigid bodies; the rigid body motion is due to hydrodynamical forces and gravity. The solu tion method combines finite element approximations, time discretization by operators splitting and conjugate gradient algorithms for the solution of t he linearly constrained quadratic minimization problems coming from the spl itting method. We conclude this article by the presentation of numerical re sults concerning the simulation of an incompressible viscous flow around a NACA0012 airfoil with a fixed center, but free to rotate, then the sediment ation of circular cylinders in 2-D channels, and finally the sedimentation of spherical balls in cylinders with square cross-sections. (C) 2000 Elsevi er Science S.A. All rights reserved.