This paper deals with the numerical computation of elastoacoustic vibration
modes. We consider a redundant description of the fluid by means of pressu
re and displacement potential variables introduced by Morand and Ohayon. We
analyze a finite element discretization leading to a well posed symmetric
banded eigenvalue problem. An iterative algorithm requiring to solve sparse
linear systems with one: degree of freedom per fluid node is obtained. We
show that, for acoustic models, this method coincides with a consistent dis
cretization of the standard potential formulation. Numerical experiments ar
e included to validate the proposed methodology for elastoacoustic vibratio
ns. (C) 2001 IMACS. Published by Elsevier Science B.V. All rights reserved.