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arXiv · 2112.14864

A high-order unfitted finite element method for moving interface problems

Chuwen Ma·Weiying Zheng
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Abstract

We propose a $k^{\rm th}$-order unfitted finite element method ($2\le k\le 4$) to solve the moving interface problem of the Oseen equations. Thorough error estimates for the discrete solutions are presented by considering errors from interface-tracking, time integration, and spatial discretization. In literatures on time-dependent Stokes interface problems, error estimates for the discrete pressure are usually sub-optimal, namely, $(k-1)^{\rm th}$-order, under the $L^2$-norm. We have obtained a $(k-1)^{\rm th}$-order error estimate for the discrete pressure under the $H^1$-norm. Numerical experiments for a severely deforming interface show that optimal convergence orders are obtained for $k = 3$ and $4$.

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Chuwen Ma, Weiying Zheng. 2021-12-29. A high-order unfitted finite element method for moving interface problems. https://arxiv.org/abs/2112.14864

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