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arXiv · 1508.05695

A Hybridized Formulation for the Weak Galerkin Mixed Finite Element Method

Lin Mu·Junping Wang·Xiu Ye
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Abstract

This paper presents a hybridized formulation for the weak Galerkin mixed finite element method (WG-MFEM) which was introduced and analyzed for second order elliptic equations. The WG-MFEM method was designed by using discontinuous piecewise polynomials on finite element partitions consisting of polygonal or polyhedral elements of arbitrary shape. The key to WG-MFEM is the use of a discrete weak divergence operator which is defined and computed by solving inexpensive problems locally on each element. The hybridized formulation of this paper leads to a significantly reduced system of linear equations involving only the unknowns arising from the Lagrange multiplier in hybridization. Optimal-order error estimates are derived for the hybridized WG-MFEM approximations. Some numerical results are reported to confirm the theory and a superconvergence for the Lagrange multiplier.

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Lin Mu, Junping Wang, Xiu Ye. 2015-08-24. A Hybridized Formulation for the Weak Galerkin Mixed Finite Element Method. https://arxiv.org/abs/1508.05695

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