Numerical study of the stability of the Interior Penalty Discontinuous Galerkin method for the wave equation with 2D triangulations

We are interesting in the well known Interior Penalty Discontinuous Galerkin method applied to the acoutic wave equation. More precisely, we propose a numerical study to determine the most suitable choice for the coefficient of penalization involved in the method. In a previous work, we have explained anlytically how to choose, in the one dimensional case, this coefficient and we have proposed an extension to squared meshes in 2D and cubic meshes in 3D. Herein, the purpose of this work is to determine numerically the best choice of this coefficient for triangular 2D meshes and the consequences over the CFL condition.