DISPLACEMENT/PRESSURE BASED MIXED FINITE ELEMENT FORMULATIONS FOR ACOUSTIC FLUID-STRUCTURE INTERACTION PROBLEMS

We present reliable Þnite element discretizations based on displacement/pressure interpolations for the analysis of acoustic ßuidÐstructure interaction problems. The Þnite element interpolations are selected using the inf-sup condition, and emphasis is given to the fact that the boundary conditions must satisfy the mass and momentum conservation. We show that with our analysis procedure no spurious non-zero frequencies are encountered, as heretofore calculated with other displacement-based discretizations