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arXiv · 2410.00687

High-order primal mixed finite element method for boundary-value correction on curved domain

Yongli Hou·Yi Liu·Tengjin Zhao
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Abstract

This paper addresses the non-homogeneous Neumann boundary condition on domains with curved boundaries. We consider the Raviart-Thomas element (RTk ) of degree $k \geq 1 $on triangular mesh. on a triangular mesh. A key feature of our boundary value correction method is the shift from the true boundary to a surrogate boundary. We present a high-order version of the method, achieving an $O(h^k+1/2)$ convergence in $L^2$-norm estimate for the velocity field and an $O(h^k )$ convergence in $H^1$-norm estimate for the pressure. Finally, numerical experiments validate our theoretical results.

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Yongli Hou, Yi Liu, Tengjin Zhao. 2024-10-01. High-order primal mixed finite element method for boundary-value correction on curved domain. https://arxiv.org/abs/2410.00687

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