Research On The Characteristics Of Wave Slamming Load On The Head Of Offshore Wind Power Installation Ships Based On CFD

Offshore wind power is an important part of the global energy transformation.The installation of offshore wind turbines requires a dedicated installation ship,so offshore wind power installation ships emerged.The bow slamming load is the most serious one in installation work.In order to ensure the safety of ship operation,reasonable safety assessment of bow slamming load is required.With the development of computer technology,the method of studying slamming load is no longer limited to traditional theoretical research.In this study,computational fluid dynamics(CFD)method is used to simulate the flow field around the ship and the ship’s navigation state in waves to create a three-dimensional numerical pool.Through CFD method,can predict the slamming load of ship bow more accurately and provide reliable data reference for ship safety.Firstly,in order to verify the reliability of CFD method and software,a wind power installation ship in China is taken as the research object in this paper.The cylinder inflow slamming model in literature is simulated by CFD method,and the calculation results are compared with the test values in literature,which proves the rationality and validity of the method and software.Then,through the drawings of wind power installation ship and relevant technical parameters,the appropriate scale ratio is selected to build the ship three-dimensional model and threedimensional numerical pool.Based on CFD method,under the action of regular wave(Stokes fifth-order wave),the change of wave slamming load on the bow of ship with wave parameters is studied.Through numerical simulation and analysis,it is found that the wave slamming loads at each observation point on the bow are similar as a whole,and the whole process shows strong instantaneity.The wave slamming loads on the bow of a ship reach the maximum quickly when it contacts the horizontal surface.With the ship entering the water,the Slamming Loads on each observation point reach the peak in turn,and then the peak drops rapidly until they become s Tab..Finally,the sizes of Slamming Loads on 16 observation points at different locations under the same conditions are analyzed,and the observation points with the greatest force in the selected observation points are obtained.By means of numerical simulation,it is found that observation point 13,which is closest to the water line and closest to the bow pillar,suffers the highest slamming load.Therefore,the observation point 13 is selected to further study the relationship between the slamming load curve and wavelength characteristics,the relationship between the slamming load curve and wave height characteristics,and the influence of wave steepness(wave height/wavelength)on the convergence of peak load.When the wavelength is fixed,the higher the wave height,the higher the slamming load.When the wave height is fixed,the slamming load increases first and then decreases.When the wavelength is twice the captain’s,the slamming load reaches its peak value.With the increase of wave steepness(wave height/wavelength),the peak value of slamming load increases first and then decreases,and the peak value gradually tends to s Tab.ilize,and the convergence of peak value of slamming load increases.The research is based on CFD method to carry out numerical simulation analysis on factors affecting bow slamming load of wind power installation ship,which provides certain reference value for structure design and operation of installation ship.