Numerische Mathematik

, Volume 100, Issue 1, pp 91–115

# A Lagrange multiplier method for the finite element solution of elliptic interface problems using non-matching meshes

• Peter Hansbo
• Ilaria Perugia
• Giancarlo Sangalli
Article

## Summary.

In this paper we propose a Lagrange multiplier method for the finite element solution of multi-domain elliptic partial differential equations using non-matching meshes. The interface Lagrange multiplier is chosen with the purpose of avoiding the cumbersome integration of products of functions on unrelated meshes (e.g, we will consider global polynomials as multiplier). The ideas are illustrated using Poisson’s equation as a model, and the proposed method is shown to be stable and optimally convergent. Numerical experiments demonstrating the theoretical results are also presented.

## Keywords

Differential Equation Partial Differential Equation Numerical Experiment Theoretical Result Mathematical Method
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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• Peter Hansbo
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