Numerische Mathematik

, Volume 95, Issue 1, pp 29–51

# Finite element analysis of pressure formulation of the elastoacoustic problem

• A. Bermúdez
• P. Gamallo
• L. Hervella-Nieto
• R. Rodríguez
Article

## Abstract

In this paper we analyze the non symmetric pressure/displacement formulation of the elastoacoustic vibration problem and show its equivalence with the (symmetric) stiffness coupling formulation. We introduce discretizations for these problems based on Lagrangian finite elements. We show that both formulations are also equivalent at discrete level and prove optimal error estimates for eigenfunctions and eigenvalues. Both formulations are rewritten such as to be solved with a standard Matlab eigensolver. We report numerical results comparing the efficiency of the methods over some test examples.

## Keywords

Error Estimate Finite Element Analysis Pressure Formulation Discrete Level Vibration Problem
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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## Authors and Affiliations

• A. Bermúdez
• 1
• P. Gamallo
• 2
• L. Hervella-Nieto
• 3
• R. Rodríguez
• 4