Author(s)

P.P. Valente & H.L.G. Pina

Abstract

A key issue in the Boundary Element Method is the solution of the associ- ated system of algebraic equations. The matrices of this systems are dense and sometimes ill conditioned. For tridimensional problems, with large scale systems (several thousand of equations) direct methods like Gauss elimination become too expensive and iterative methods may be preferable. For these problems there are already many algorithms, namely for general nonsymmetric systems. Most of them can be viewed as Lanczos or Conjugate Gradient-like solvers. Here we present some iterative techniques based on Con- jugate Gradient solvers as Descent Methods (DM), Bi-Conjugate Gradients (Bi- CG), Conjugate

Keywords