Seakeeping Study Of Wave Adaptive Rescue Boat

With the implementation of the strategy of maritime power and the increasing maritime activities,higher demands and new challenges have been put forward for the rescue and protection of lives and properties at sea.At present,the existing rescue ships in our country are all too large nor too old,and lack of high performance small rescue boats for offshore rescue.Therefore,a high performance rescue ship with wave adaptive function was developed.In this thesis,the seakeeping ability of the wave adaptive rescue boat was studied.The wave adaptive rescue ship took the Wave Piercing Catamaran as the design prototype,so this thesis referred to the research methods of seakeeping study of WPC.The motion equations of Wave Piercing Catamaran were given,after analyzing the force of the wave adaptive rescue ship,the motion equations of the vertical motion ship were given,and the calculation method of hydrodynamic coefficient was introduced.Finally,the spectrum analysis method was presented.The different effects of different spring stiffness,damping coefficient and different load on the pay load tary was discussed.After the modeling in SolidWorks,using Hydrostar to calculate the hydrodynamic coefficient,finally,the simulation of the seakeeping abilities of the wave adaptive rescue boat was carried out in Matlab.The result showed that the effect of the damping system increases with decrease of spring stiffness and damping coefficient.The experiment of the prototype of the wave adaptive rescue boat was carried out after the installation of the data acquisition and storage devices,the seakeeping of the boat was tested in different spring stiffness and damping coefficient,and the simulation results was verified,the seakeeping performance under different wave conditions of the boat was discussed,which shows that the seakeeping abilities increases as the wave condition get worse.According to the results of the experiment,it was found that the drainage of the boat was too small,and the design of the principle dimension was unreasonable,and the the effects of the damping system is not obvious.In order to solve the above problems,optimization design of the prototype of the wave adaptive rescue boat was carried out,the main scale coeffcients are recalculated and redesigned,the seakeeping of the redesigned boat and the prototype were compared,which verifies the effect of the optimization.At the same time,the shock absorber was reselected,and the structure of the damping system was redesigned.