A stabilizer free WG method is introduced for the Stokes equations with superconvergence on polytopal mesh in primary velocity-pressure formulation. Convergence rates two order higher than the optimal-order for velocity of the WG approximation is proved in both an energy norm and the $ L^2 $ norm. Optimal order error estimate for pressure in the $ L^2 $ norm is also established. The numerical examples cover low and high order approximations, and 2D and 3D cases.
Citation: Xiu Ye, Shangyou Zhang. A stabilizer free WG method for the Stokes equations with order two superconvergence on polytopal mesh[J]. Electronic Research Archive, 2021, 29(6): 3609-3627. doi: 10.3934/era.2021053
A stabilizer free WG method is introduced for the Stokes equations with superconvergence on polytopal mesh in primary velocity-pressure formulation. Convergence rates two order higher than the optimal-order for velocity of the WG approximation is proved in both an energy norm and the $ L^2 $ norm. Optimal order error estimate for pressure in the $ L^2 $ norm is also established. The numerical examples cover low and high order approximations, and 2D and 3D cases.
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