Mathematics Colloquium: A Lagrange multiplier based domain decompositn method for wave propagatn in heterogeneous media

2007-03-19

4:10 p.m. Cleveland 247

Sergei Lapin

Abstract: The main goal of this talk is to address the numerical solution of a wave equation with discontinuous coefficients by a finite element method using domain decomposition and semimatching grids. A wave equation with absorbing boundary conditions is considered, the coefficients in the equation essentially differ in the subdomains. The problem is approximated by an explicit in time finite difference scheme combined with a piecewise linear finite element method in the space variables on a semimatching grids. The matching condition on the interface is taken into account by means of Lagrange multipliers. The resulting system of linear equations of the saddle-point form is solved by a conjugate gradient method.