George Biros : Fast solvers for elliptic PDEs in complex geometrie

The simplest example of a boundary value problem is the Dirichlet Poisson problem: we seek to recover a function, defined on a smooth domain, its values at the boundary of the domain and the divergence of its gradient for all points inside the domain. This problem has been studied for more than 200 years, and has many applications in science and engineering. Analytic solutions are available only for a limited number of cases. Therefore one has to use a numerical method. The basic goals in designing a numerical method is guaranteed quality of the solution, in reasonable time, in a black-box fashion. Surprisingly, a robust, black-box, algorithmically scalable method for the Poisson problem does not exist. The main difficulties are related to robust mesh generation in complex geometries in three dimensions. I will review different approaches in solving the Poisson problem and present a new method based on classical Fredholm integral equation formulation. The main components of the new method are a kernel-independent fast summation method, manifold surface representations, and superalgebraically accurate quadrature methods. The method directly extends to problems with non-oscillatory known Green's functions. In addition to the Poisson problem I will present results for the Navier, modified Poisson, and Stokes operators.

• Category: Applied Math and Analysis
• Duration: 01:30:55
• Date:  May 12, 2006 at 4:25 PM
• Views: 159
• Tags:   seminar, Applied Math And Analysis Seminar