A fictitious domain approach to the direct numerical simulation of incompressible viscous flow past moving rigid bodies: Application to particulate flow

In this article we discuss a methodology that allows the direct numerical s imulation of incompressible viscous fluid flow past moving rigid bodies. Th e simulation methods rest essentially on the combination of: (a) Lagrange-multiplier-based fictitious domain methods which allow the flu id Row computations to be done in a fixed flow region. (b) Finite element approximations of the Navier-Stokes equations occurring in the global model. (c) Time discretizations by operator splitting schemes in order to treat op timally the various operators present in the model. The above methodology is particularly well suited to the direct numerical s imulation of particulate flow, such as the How of mixtures of rigid solid p articles and incompressible viscous fluids, possibly non-Newtonian. We conc lude this article with the presentation of the results of various numerical experiments, including the simulation of store separation for rigid airfoi ls and of sedimentation and fluidization phenomena in two and three dimensi ons. (C) 2001 Academic Press.