Spurious velocities in the steady flow of an incompressible fluid subjected to external forces

Jean-Frédéric Gerbeau (1) , Claude Le Bris (1, 2) , Michel Bercovier (3)

1 CERMICS - Centre d'Enseignement et de Recherche en Mathématiques et Calcul Scientifique
2 MICMAC - Methods and engineering of multiscale computing from atom to continuum
3 The Rachel and Selim Benin School of Computer Science and Engineering

We show that a non physical velocity may appear in the numerical computation of the flow of an incompressible fluid subjected to external forces. A distorted mesh and the use of a numerical method which does not rigorously ensure the incompressibility condition turn out to be responsible for this phenomenon. We illustrate it with numerical examples and we propose a projection method which improves the results.

Mots clés: Incompressible fluid; finite element; spurious velocity

Domaines: Analyse numérique [math.NA]

Jean-Frédéric Gerbeau, Claude Le Bris, Michel Bercovier. Spurious velocities in the steady flow of an incompressible fluid subjected to external forces. International Journal for Numerical Methods in Fluids, 1997, 25 (6), pp.679-695. ⟨10.1002/(SICI)1097-0363(19970930)25:6<679::AID-FLD582>3.0.CO;2-Q⟩. ⟨hal-00690238⟩