Hi all, I've written a program that solves the Poisson equation in an irregular mesh, using a finite volume discretization. the method works well, and the solution is very good at a distance of 2-3 mesh sizes off of the source. The problem is that I need to know what is the contribution of the nodes to their neighbors- a place too close to have an accurate solution (i.e. m/r)- my question is, how could this be calculated? or- is there a method to impose the influence to be m/r? Thanks in advance, Ariel.