A preliminary bibliographic survey was conducted, explaining concepts as mass effect and void ratio as well as looking into other papers with relevant previous results. The numerical model used was that of a fluid-solid interaction. A harmonic analysis type was chosen for the plate modes and a modal type for the acoustic modes. The geometry studied consists of a circular plate surrounded by a two-phase fluid, a mixture of air and water. This mixture was defined by its void-ratio parameter, which is dependent on the density and the sound speed. Ansys simulations were conducted in order to find the wanted modes of vibration for the plate and the acoustic modes for the surrounding fluid. The acoustic modes of vibration (considering all solid eliminated) were analysed, studying its frequency’s dependence on void ratio, density and sound speed and comparing its mode shapes. Fluid-structure coupled modes of vibration for the plate were also studied, to be more specific those with an axisymmetric circular shape. Finally, the coupling effect between the acoustic and the structural modes was studied. The results confirm that a dependence between the plate modes of vibration and the surrounding mixture exists, and it’s ruled by the mixture density. A big coupling effect between some acoustic modes and plate modes was also found, which made the further analysis of the plate modes of vibration difficult
