ABSTRACT

In this study, the hydroelastic vibration analysis of clamped rectangular plates vertically in contact with quiescent fluid is carried out. The method of analysis is divided into two parts; namely, in-vacuo and wet. Both in-vacuo and wet analyses are conducted by the novel isogeometric NURBS concept; the in- vacuo analysis is carried out by the isogeometric FEM, while, wet analyses are performed by the isogeometric BEM. In in-vacuo analysis, the Kirchhoff thin plate theory is adopted, and the isogeometric FEM formulation for Kirchhoff plate is presented. In wet analysis, fluid is assumed non- viscous and incompressible; the rotational motions of the fluid is neglected. It is also assumed that fluid actions and related pressure distribution over the structure only occur due to modal vibrations of the structure; in other words, it is assumed that both the elastic structure and the surrounding fluid has no forward speed. The linear hidroelasticity theory is adopted in order to determine the wet dynamic characteristics of the structure under the fluid-structure interaction forces. In-vacuo and wet dynamic characteristics (natural frequencies and corresponding mode shapes) are presented comparatively with the available analytical and experimental results in the literature. It is concluded that the present work demonstrates the versatility of the isogeometric analysis concept.