Weak Galerkin Finite Element Methods on Polytopal Meshes

TL;DR

This paper presents a novel weak Galerkin finite element method for second order elliptic equations on arbitrary polytopal meshes, providing optimal error estimates and demonstrating robustness through numerical experiments.

Contribution

The paper introduces a new WG-FEM that works on arbitrary polytopal meshes with proven optimal error estimates and demonstrated accuracy.

Findings

Optimal order error estimates in $H^1$ and $L^2$ norms.

Numerical results confirm robustness and accuracy.

Method applicable to general polytopal meshes.

Abstract

This paper introduces a new weak Galerkin (WG) finite element method for second order elliptic equations on polytopal meshes. This method, called WG-FEM, is designed by using a discrete weak gradient operator applied to discontinuous piecewise polynomials on finite element partitions of arbitrary polytopes with certain shape regularity. The paper explains how the numerical schemes are designed and why they provide reliable numerical approximations for the underlying partial differential equations. In particular, optimal order error estimates are established for the corresponding WG-FEM approximations in both a discrete $H^1$ norm and the standard $L^2$ norm. Numerical results are presented to demonstrate the robustness, reliability, and accuracy of the WG-FEM. All the results are derived for finite element partitions with polytopes. Allowing the use of discontinuous approximating functions on arbitrary polytopal elements is a highly demanded feature for numerical algorithms in scientific computing.