A direct finite element method for elliptic interface problems

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Hu, Jun, Ma, Limin
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915447721426944
author Hu, Jun
Ma, Limin
author_facet Hu, Jun
Ma, Limin
contents In this paper, a direct finite element method is proposed for solving interface problems on unfitted meshes. This new method treats the two interface conditions as an $H^{\frac12}(Γ)\times H^{-\frac12}(Γ)$ pair for the mutual interaction across the interface, rather than the jumps of variables. A simple and straightforward finite element method is proposed based on this approach. This method solves the interface problem using conforming finite elements in one subdomain and conforming mixed finite elements in the other, with a natural integral term accounting for mutual interaction. Under reasonable assumptions, this direct finite element method is proved to be well-posed with an optimal a priori error analysis. Moreover, a simple lowest-order direct finite element method, using the linear element and the lowest-order Raviart-Thomas element, is analyzed to achieve the optimal a priori error estimate by verifying the aforementioned assumptions. Numerical tests are provided to confirm the theoretical results and the effectiveness of the direct finite element method.
format Preprint
id arxiv_https___arxiv_org_abs_2401_16967
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle A direct finite element method for elliptic interface problems
Hu, Jun
Ma, Limin
Numerical Analysis
65N30
In this paper, a direct finite element method is proposed for solving interface problems on unfitted meshes. This new method treats the two interface conditions as an $H^{\frac12}(Γ)\times H^{-\frac12}(Γ)$ pair for the mutual interaction across the interface, rather than the jumps of variables. A simple and straightforward finite element method is proposed based on this approach. This method solves the interface problem using conforming finite elements in one subdomain and conforming mixed finite elements in the other, with a natural integral term accounting for mutual interaction. Under reasonable assumptions, this direct finite element method is proved to be well-posed with an optimal a priori error analysis. Moreover, a simple lowest-order direct finite element method, using the linear element and the lowest-order Raviart-Thomas element, is analyzed to achieve the optimal a priori error estimate by verifying the aforementioned assumptions. Numerical tests are provided to confirm the theoretical results and the effectiveness of the direct finite element method.
title A direct finite element method for elliptic interface problems
topic Numerical Analysis
65N30
url https://arxiv.org/abs/2401.16967