Summary: | 碩士 === 國立成功大學 === 水利及海洋工程學系 === 104 === This research is basically focused on 3-D water wave induced by landslide. Since it involves moving boundaries and large deformation of the computational domain, a 3-D numerical model is established with a meshless method and a fully nonlinear Lagrangian time marching scheme. Robust local polynomial collocation method which developed in the way that the collocations have to satisfy governing and boundary condition if it is the boundary point used in this study. This method is more efficient and accurate than the RBF-collocation method. Furthermore, due to its Lagrangian description of the flow motion, meshless method is effective in dealing with moving boundary problems such as free surface, landslide and wave-maker. Three dimensional experiments which regular waves pass an uneven bottom are chosen for simulation in order to validate the model. A fairly good agreement observed by comparing with the experiment data indicates that this model can successfully capture wave propagation phenomenon. The present numerical results which wave generated by a submerged landslide are compared with other numerical solutions using high-order Boussinesq-type model and experiment data in order to validate the ability of solving moving boundary problems in this meshless model. The results of simulation indicated that the present method is better than high-order Boussinesq-type model. Besides, the present model could predict the run-up height accurately. In this study, the edge waves caused by landslide-induced waves is disscussed and proved that the landslide-induced waves would cause edge waves by time-frequency analysis with wavelet transform.
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