| Summary: | Thesis (M.Eng.)--Memorial University of Newfoundland, 1994. Engineering and Applied Science Bibliography: leaves 90-94. This study deals with the dynamic characteristics of plates submerged in water using analytical and experimental methods. The plates considered have two kinds of boundary conditions, one with clamped-free-clamped-free(CFCF) supports, another with simple-free-simple-free(SFSF) supports. They are submerged in water at different depths. -- For the experimental study, modal testing of the two plates is carried out in air and in water. The effect of the depth of submergence of the plate is investigated. The simply supported condition was simulated by using a notched plate with a damped end and the finite element software ABAQUS is used to determine the dimensions of the notch. The appropriateness of the tested plates as models of the CFCF and SFSF plates is verified. The added mass factor, which is used to account for the decrease in natural frequencies, and the increase in modal damping ratios for the vibrating plates submerged in water have been evaluated for the first five modes. The effect of the plate boundary conditions on the vibration of plates in water is also investigated. -- In the analytical study, a thin plate undergoing a flexural bending vibration in a body of homogeneous, incompressible and inviscid fluid whose motion is irrotational, is considered. The governing equation for the surface displacement of the plate-fluid system is derived. In the effort to solve the velocity potential, the general linearized fluid free surface boundary condition is applied. The relationship between the added mass and the depth of submergence above and below the plate is established. -- The analytical solution is applied to the CFCF and SFSF plates submerged in water, and the experimental and analytical studies on the added mass due to the presence of fluid are compared. The maximum difference between the measured and the predicted added mass factors is found to be within 7.916%.
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