Numerical Simulation Of The 2-D Interaction Between Solitary Wave And Submerged Structure

When coastal storms or typhoons arrive,bridge slabs,docks and other coastal structures could be completely submerged into the water due to rising water levels.Similarly,the submerged structures can be used as breakwater,to disperse the energy of wave,playing an important role in reducing coastal erosion and protecting coastal structures.In addition,the lower part of some semi-submerged very-large floating structure or offshore platform serves as the submerged floating units.Theretically,solitary waves belong to the shallow water waves of large amplitude,which can be used to simulate the effects of shallow water waves or tsunamis on coastal structures.Interaction between a solitary wave and a submerged plate belong to one of classic subject in water wave dynamics.Detailed investigation on wave loads on the submerged plate under the effect of a solitary is of great interests in practice in the field of coastal and offshore engineering.The main work of this thesis is:1.A two-dimensional boundary element numerical wave tank is established and verified for the generation and propagation of a solitary wave.The accuracy of the program is verified by the flow around a submerged horizontal circular cylinder and the fission of solitary waves on the step.On the basis of this,the interaction between solitary wave and horizontal cylinder is studied.Through a large number of numerical simulations,the mechanism of the force on the cylinder is more clearly understood,including the characteristics of the moment of the extreme value of the force,the effect of depth on the waves.2.The interaction between the solitary wave and the submerged plate is studied by numerical simulation.The influence of the relative amplitude,the relative depth of immersion and the relative plate length on the hydrodynamic loads on a plat is analyzed.The difference between the mechanism of the changes of the characteristic wave loads owing to the submerged depth of a plate is presented.3.For the case where the seabed terrain under the submerged plate is a slope,the influence of the slope on the vertical force of the plate is analyzed by numerical simulation,and the mechanism of the vertical hydrodynamic force on the submerged plate is explained by the pressure distribution on the upper and lower surfaces of the plate.