Numerical Studies On The Contact Collision Of Multiple Floating Bodies Based On SPH

As the ocean development gradually moving towards the polar and deep ocean,we encounter more and more complex multiple floating bodies problem,which is quite different from a single body about the hydrodynamic response.The collision and stack of sea ice are typical multiple floating bodies problem.Although the traditional grid-based numerical method have been widely used in science and engineering,but there are still shortcomings.For example,generating high quality grids requires a lot of time;the grid distortion will seriously affect the calculation accuracy.These limitations make traditional grid method cannot be applied to many problems.The smoothed particle hydrodynamics method(SPH)just makes up for the shortcomings of the traditional grid method.As a lagrangian particle method,SPH is free for grid.Not only solved the difficulties in mesh generation,but also avoid the grid distortion and reconstruction.As one of the fluid-structure interaction problems,the fluid surrounding the floating body becomes very complex.It will become very difficult to use the traditional grid method.Therefore,based on the fully study of the smooth particle hydrodynamics method,this paper mainly focus on the research of fluid-structure interaction between the fluid and floating body as well as the contact algorithm between the floating bodies.Finally,based on SPH method to develop a program to achieve the simulation between the floating bodies.The main content of this paper involves the following five aspects:1)Introduce the basic theory of SPH and the derivation of the SPH method in detail.Some key problems in SPH model are also discussed.2)Realize the simulation of 2d dam and push plate wave-making(including linear and nonlinear wave).by comparing the results with the corresponding experiments and theoretical solutions to verify the reliability of the results and accuracy of the calculation results.3)Research the fluid-structure interaction between the floating body and the fluid,including the floating particles and fluid particle processing,equations of motion of the floating body solving,etc.Then,accomplish the simulation and validation of relevant single floating body based on the basic theory of SPH method.4)Research the contact problems between the floating bodies in fluid and propose to use the contact algorithm dealing with the collision between floating bodies.At the same time,develop the corresponding program.5)Accomplish the numerical simulation of multiple floating bodies movement based on fluid-structure interaction and contact algorithm between floating bodies.it has laied the foundation for applying SPH numerical simulation to solve much more complicated multi-floating body problems in future.