English

A locally modified second-order finite element method for interface problems and its implementation in 2 dimensions

Numerical Analysis 2023-05-01 v2 Numerical Analysis

Abstract

The locally modified finite element method, which is introduced in [Frei, Richter: SINUM 52(2014), p. 2315-2334], is a simple fitted finite element method that is able to resolve weak discontinuities in interface problems. The method is based on a fixed structured coarse mesh, which is then refined into sub-elements to resolve an interior interface. In this work, we extend the locally modified finite element method {in two space dimensions} to second order using an isoparametric approach in the interface elements. Thereby we need to take care that the resulting curved edges do not lead to degenerate sub-elements. We prove optimal a priori error estimates in the L2L^2-norm and in a discrete energy norm. Finally, we present numerical examples to substantiate the theoretical findings.

Keywords

Cite

@article{arxiv.2007.13906,
  title  = {A locally modified second-order finite element method for interface problems and its implementation in 2 dimensions},
  author = {Stefan Frei and Gozel Judakova and Thomas Richter},
  journal= {arXiv preprint arXiv:2007.13906},
  year   = {2023}
}
R2 v1 2026-06-23T17:26:58.910Z