M.C . CICCOLI,A . DERVIEUX,J . -A . DESmERIandE.MORANOI .N .R.I .A . , B .P.93 , F-06902SophiaAntipolisC6dex,France

Abstract . The object of this article is the analysis of efficiency of computational methods employed in the simulation of steady compressible flows governed by the Euler equations or a more complex model . In these methods , an arbitrary Finite-Element­ type domain discretisation made of triangles in 2D (or tetrahedra in 3D) is assumed to be given, and an upwind Finite-Volume-type approximation scheme is constructed over the dual mesh. Second-order approximations are derived by the MUSCL extrapolation including limitation devices . The discussion emphasizes the aspects related to the solution of the resulting discrete system. Simplified models are considered for analysis . In particular the properties of the Defect-Correction implicit (pseudo-time marching) technique are reviewed in the case of a linear advection equation. An acceleration procedure is proposed based on eigenmode annihilation. Alternatively, a multigrid algorithm also applying the Defect-Correction concept is proposed. Examples of flow computations are given.