Research On Ship’s Wave Force Model In Regular Waves Based On CFD

As the development of large-scale, high speed and various hull-shape vessels, it is harder to predict ship’s maneuverability. Along with the increase of ship traffic density and environment factors such as wind, current and waves, the ship accident increases year by year. Simulation technology based on ship motion mathematical model has become an important method to predict ship’s maneuverability. The calculation precision of the wave force model in ship motion mathematical model will directly affect the accuracy of ship’s maneuverability prediction in waves.In recent years, with the computing ability of computer greatly improved, ship CFD method is improved and the algorithm constantly is update, so calculation precision is also gradually improved. Compared with physical wave tank test, numerical wave tank has many advantages, such as low cost, short research period, without scale effect and so on. It is of great significance and value to predict ship’s maneuverability.In this paper, the training vessel YUKUN of Dalian Maritime University is taken as object of research. The3D model of ship hull is firstly established with CAD software based on YUKUN’s lines plan. Secondly, based on the3D model the geometry of numerical wave tank is made, and the computational domain is divided with hexahedron mesh. According to the numerical simulation of test conditions, this paper chose proper CFD mathematical model and define the boundary conditions. Then proceeded the iterative calculation by the commercial software FLUENT. In this paper, the VOF multiphase model, RNG k-ε turbulence model and high order Stokes wave model air used. No-slip condition and standard wall function are used to treat near wall flow. SIMPLE method is used to solve the pressure-velocity coupling equations, and second order upwind scheme was used to discrete control equations. YUKUN resistance numerical test is carried out. After regressing the test result, the resistance coefficient curve of YUKUN is obtained. Then add the coefficient curve to the MMG model and simulate turning motion by software MATLAB. By comparing the simulation results with those of real ship test, it comes to a conclusion that it is available to research ship hydrodynamic coefficients with CFD method and the results have a high accuracy. Then the numerical simulations of ship trials in longitudinal waves and transverse waves are made and received the wave force of YUKUN in waves of near shore parameters. After fitting these two sets of numerical simulation results, the wave force regression formula of YUKUN sailing in near shore longitudinal waves and transverse waves are obtained. After verification, the regression model obtained from this paper is of high accuracy to be applied in engineering projects.