On the stability of colocated clustered finite volume simplicial discretizations for the 2D Stokes problem
Titre de la revue : Calcolo
Volume : 44
N° : 4
Pagination : 219-234
Date de publication : 01/12/2007
In this paper, we give a new (and simpler) stability proof for a cell-centered colocated finite volume scheme for the 2D Stokes problem, which may be seen as a particular case of a wider class of methods analyzed in . The definition of this scheme involves two grids. The coarsest is a triangulation of the computational domain by acute-angled simplices, called clusters. The control volumes grid is finer, built by cutting each cluster along the lines joining the mid-edge points to obtain four sub-triangles. By building a Fortin projection operator explicitly, we prove that the pair of discrete spaces associating the classical cell-centered approximation for the velocities and cluster-wide constant pressures is inf-sup stable. In a second step, we prove that a stabilization which involves pressure jumps only across the internal edges of the clusters yields a stable scheme with the usual colocated discretization (i.e., with the cell-centered approximation for the velocity and the pressure). Lastly we give an interpretation of this stabilization as a -minimal stabilization procedure-, as introduced by Brezzi and Fortin.