Dispersion analysis of stabilized finite element methods for acoustic fluid interaction with Reissner-Mindlin plates

The application of stabilized nite element methods to model the vibration of elastic plates coupled with an acoustic uid medium is considered. A complex-wavenumber dispersion analysis of acoustic uid interaction with Reissner{Mindlin plates is performed to quantify the accuracy of stabilized nite element methods for uid-loaded plates. Results demonstrate the improved accuracy of a recently developed hybrid least-squares (HLS) plate element based on a modi ed Hellinger{Reissner functional, consistently combined with residual-based methods for the acoustic uid, compared to standard Galerkin and Galerkin gradient least-squares plate elements. The technique of complex wavenumber dispersion analysis is used to examine the accuracy of the discretized system in the representation of free waves for uid-loaded plates. The in uence of uid and coupling matrices resulting from consistent implementation of pressure loading in the residual for the plate equation is examined and clari ed for the di erent nite element approximations.