| In this paper, the wave-making problems of submerged moving bodies are simulated using a time domain algorithm under the assumptions of potential flow.First, a 3D boundary element integral equation is given using the 3D transient free surface Green's function with consideration of nonlinear body surface condition. In order to validate the feasibility of the theoretical model and reliability of numerical implementation, a comparison of the wave resistance solution of a submerged spheroid between the author's results and known numerical results has been made. The results show excellent agreements between them. Then the numerical model has been developed to solve the hydrodynamic problem of underwater landslide with varying acceleration that is one of the most interesting problems of coastal engineering now.Then, a 3D analytical solution of induced velocity acting on a submerged spheroid advancing with a constant speed in an unbounded fluid has been given, and then a 2D analytical solution based on the slender theory has also been given. The applicability of slender body theory has been investigated during the comparison between 3D and 2D analytical results.Thirdly, the 2D transient free-surface Green's function is used to solve the formulation based on 2D+t potential theory. We have compared the results calculated by both 3D and 2D+t numerical methods with 3D analytical results. By numerical comparison, it is determined that the 3D numerical results can be used to check the reliability of 2D+t theory and 2D+t theory is valid in high speed range.Finally, the steady flow induced by a submerged spheroid advancing with a constant speed near the free surface has been calculated using 2D+t theory and compared with 3D numerical model. The flow characteristics for the submerged moving spheroid with a parallel body have been further investigated. Present work will play a foundation for hydrodynamic research of large amplitude method between ship and waves. |
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