Numerical Simulation Of Three-dimensional Wave-Body Interaction

A simulation method of radiation condition-MTF(multi-transmittingformula) which is widely used in many fields such as seismology and electromagnetic engineering is introduced in this paper. An attempt is made to apply the ABC (artificial-boundary condition) which is based on the MTF into hydrodynamics field to solve wave radiation and diffraction problems. Some techniques of choosing parameters are summarized to implement the ABC.A numerical model based on the boundary element method has been presented to solve the problem of wave radiation around three-dimensional body. As an example, the model is used to solve the problem of regular wave radiation around a hemi-sphere. Some parameters such as time step, panel size, artificial-velocity of waves, the distance and shape of the artificial boundary surface etc. are studied to get the steady results. The potentials on the free surface and the hydrodynamic forces acting on the hemi-sphere are given. All these prove that this method can simulate the radiation condition well.Another numerical model is presented to solve the problem of regular and irregular waves diffraction around a 3D vertical circular cylinder. The numerical results agree with the theoretical results well. Since the irregular waves problems in hydrodynamics are difficult to solve in some usual methods, this new method may help to solve these problems in an alternative way.Finally, a wigley model is introduced to replace the vertical circular cylinder in the regular wave diffraction problems. Here the artificial boundary surface consists of four rectangular surfaces. The heave wave forces and the surge wave forces are given.