Ahmad Reza Kohansal

In this study, we investigated the free vibrations of a marine aluminum plate that has a central crack and floats on water and evaluated the natural frequencies of the plate. The method used on the governing equations is the Galerkin free element method (EFG) and we used the moving least squares method (MLS) to obtain and approximate the shape functions. Also, in order to simulate and apply the effect of water on the plate, we used the simple method of adding mass. Rectangular plate and simple support conditions are considered. First, validation was done for healthy plate, plate in contact with water, and plate with cracks, and after ensuring the accuracy of the method, we changed different parameters such as the size and angle of the crack, plate thickness, and plate dimensions to determine the effect of each on the plate natural frequency. evaluate. Finally, one of the results of the method was the reduction of the natural frequency of the cracked plate in contact with water compared to the healthy plate in vacuum.