The Numerical Simulation Of The Motion Of Float In The Numercical Wave Tank

In the research of ships,the performance of ships is generally researched and evaluated through the physical experiment pool,and various types of ship pools have been built in many countries in the world in the early days.The ship physical pool is usually divided into three categories: model towing pool,seakeeping pool and maneuvering pool,and ocean engineering pool.In recent years,there have been propeller cavity pools.With the rapid development of high-performance computer resources and CFD technology,the numerical wave tank has attracted more and more researchers’ attention due to its rich and diverse functions and low cost for prediction.The advantages and disadvantages of the numerical wave tank and the traditional physical experiment pool are complementary,which has become an indispensable and important means for the research on the hydrodynamic performance of ships,the interaction between waves and Marine structures,and the wave energy to generate electricity.The main research content of this paper is to independently establish a two-dimensional numerical wave tank to realize the functions of wave generation and wave elimination,and finally learn the effect between waves and structures.In this paper,based on FLUENT fluid software.Firstly,a two-dimensional numerical tank was established,and three wave making methods,namely piston type wavemaker,method of defining inlet boundary condition and open channel flow,were used to simulate the linear micro-amplitude wave and Stokes second-order wave respectively,and the accuracy of wave making was compared with the theoretical value.According to the results,using the same grid to calculate,the time of piston type wavemaker is obviously longer,but the wave height is most consistent with the theoretical value.The waveform produced by the method of defining inlet boundary condition is quite different from the theoretical waveform.The wave damping of open channel flow is very serious,but it can be improved by using an nicer grid.Secondly,the relationship between the wave and the floating ball was studied,the motion response of the stationary floating ball in the wave and the motion of the moving floating ball in the wave were simulated,and the factors affecting the motion amplitude and frequency of the floating ball were summarized and analyzed.In the calculation of static floating ball,the existence of the floating ball will affect the nearby wave amplitude,and there is local high pressure near the floating ball.In the simulation of the moving floating ball,it is found that the motion distance of the center of gravity of the floating ball is close to the wave height,and the motion frequency is approximately equal to the wave period.