Artificial boundaries and formulations for the incompressible Navier-Stokes equations. Applications to air and blood flows.

International audienceWe deal with numerical simulations of incompressible Navier-Stokes equations in truncated domain. In this context, the formulation of these equations has to be selected carefully in order to guarantee that their associated artificial boundary conditions are relevant for the considered problem. In this paper, we review some of the formulations proposed in the literature, and their associated boundary conditions. Some numerical results linked to each formulation are also presented. We compare different schemes, giving successful computations as well as problematic ones, in order to better understand the difference between these schemes and their behaviours dealing with systems involving Neumann boundary conditions. We also review two stabilization methods which aim at suppressing the instabilities linked to these natural boundary conditions

Oseen Problem

with Advection 10:00- 10:30 G. Rapin A Non-Conforming Domain Decomposition Method for Advection-Diffusion 11 Equations 10:30- 11:00 Coffee brea

A three-level finite element method for the instationary incompressible Navier-Stokes equations

SIGLEAvailable from TIB Hannover: RR 6943(2003,26) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

On Large Eddy Simulation and Variational Multiscale Methods in the numerical simulation of turbulent incompressible flows

summary:Numerical simulation of turbulent flows is one of the great challenges in Computational Fluid Dynamics (CFD). In general, Direct Numerical Simulation (DNS) is not feasible due to limited computer resources (performance and memory), and the use of a turbulence model becomes necessary. The paper will discuss several aspects of two approaches of turbulent modeling—Large Eddy Simulation (LES) and Variational Multiscale (VMS) models. Topics which will be addressed are the detailed derivation of these models, the analysis of commutation errors in LES models as well as other results from mathematical analysis