# Full-Discrete Weak Galerkin Finite Element Method for Solving Diffusion-Convection Problem.

### Abstract

This paper applied and analyzes full discrete weak Galerkin (WG) finite element method for non steady two dimensional convection-diffusion problem on conforming polygon. We approximate the time derivative by backward finite difference method and the elliptic form by WG finite element method. The main idea of WG finite element methods is the use of weak functions and their corresponding discrete weak derivatives in standard weak form of the model problem. The theoretical evidence proved that the error estimate in norm, the properties of the bilinear form, (v-elliptic and continuity), stability, and the energy conservation law.

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