On the convergence of the fictitious domain method for wave equation problems

Eliane Bécache (1) , J. Rodríguez (1) , Chrysoula Tsogka (1)

1 POEMS - Propagation des Ondes : Étude Mathématique et Simulation

This paper deals with the convergence analysis of the fictitious domain method used for taking into account the Neumann boundary condition on the surface of a crack (or more generally an object) in the context of acoustic and elastic wave propagation. For both types of waves we consider the first order in time formulation of the problem known as mixed velocity-pressure formulation for acoustics and velocity-stress formulation for elastodynamics. The convergence analysis for the discrete problem depends on the mixed finite elements used. We consider here two families of mixed finite elements that are compatible with mass lumping. When using the first one which is less expensive and corresponds to the choice made in a previous paper, it is shown that the fictitious domain method does not always converge. For the second one a theoretical convergence analysis is presented in the acoustic case and numerical convergence is shown both for acoustic and elastic waves.

Mots clés: MIXED FINITE ELEMENTS; FICTITIOUS DOMAIN METHOD; ACOUSTIC WAVES; ELASTIC WAVES; CONVERGENCE

Domaines: Autre [cs.OH]

Eliane Bécache, J. Rodríguez, Chrysoula Tsogka. On the convergence of the fictitious domain method for wave equation problems. [Research Report] RR-5802, INRIA. 2006, pp.37. ⟨inria-00070222⟩