Singularity treatment when using the method of moments

I'm trying to implement a solver for the Helmholtz equation in 3D, using the Galerkin method. What is (are) the common method(s) for integration near singularity?

I know of the Duffy transformation but the mesh is very dense and the patches that have one vertex at singularity are not enough to capture the near kernel near singularity.

Thanks.

flag	asked Sep 1 2010 at 22:27 dongta 1

You forgot to mention what sort of singularities you have (algebraic, logarithmic). The best performance is (often) achieved when you tailor your variable substitutions to the type of singularity you have. – J. M. Sep 2 2010 at 10:50