A posteriori error estimates for semi-linear elliptic partial differential equations

Abstract

We derive upper and lower bounds for a posteriori error estimates in finite element solutions of semi-linear elliptic partial differential equations (PDEs) over polygonal domains in two space dimensions. We consider the Dirichlet problem for semi-linear PDEs with vanishing boundary. The estimate is based on Lagrange element, and the error estimates are computed in the energy norm with assumption of exact integration. The proof is based on the condition of function f(x, u) which have first derivative in second argument.