Superconvergent estimate of a Galerkin finite element method for nonlinear Poisson–Nernst–Planck equations.

A Galerkin finite element method (FEM) is developed for nonlinear Poisson–Nernst–Planck (PNP) equations. Based on the combination technique of the element's interpolation and Ritz projection together with the special mean value approach, the superclose and superconvergence estimates with order O (h 2) are derived under weaker regularity requirements of the exact solution. Some numerical results are provided to confirm the theoretical analysis. [ABSTRACT FROM AUTHOR]