Derefinement algorithms of nested meshes

Abstract

In this paper a new derefinement algorithm of nested triangular meshes is presented and discussed. This algorithm is combined with a local refinement. The refinement / derefinement combination, that we call readaptive process, is very useful to solve time-dependent problems in which moving refinement areas are required. The fact of using nested meshes enables us to use the multigrid method in order to solve the equation system associated to the finite element method. Moreover, a readaptive process can be used to obtain the best piece-wise triangular support to interpolate a given two dimensional function.