Research On The Capsizing Simulation For Ship Under Stochastic Wave And Wind

Virtual reality technology is used to visualize scientific achievements to the public.The simulation of ship capsizing motion also uses virtual reality technology to present the process of ship capsizing in a three-dimensional visualization way.Then,how to balance the realism and real-time is particularly important.This paper focuses on three aspects of the ship’s capsizing simulation under the action of random wind waves:the synchronous simulation algorithm of random wind field and ocean wave,the calculation model of the ship’s recovery arm under roll motion and the threedimensional visualization of the ship capsizing model.Strive to be able to simulate the whole process of the ship’s rolling motion until the capsizing under the action of external force with higher resolution.To achieve this goal.The main research is as follows:Firstly,aiming at the periodic problem of the existing method for the synchronous simulation of random wind and ocean waves,an improved algorithm for the same frequency superposition of random wind and ocean wave is proposed.When selecting the frequency interval,the method considers the random wind and the ocean wave simultaneously,ignoring the low frequency and the high frequency,and centrally selecting the same frequency portion of the wind spectrum and the wave spectrum.In order to obtain random wind and wave simulation results,when selecting discrete points,two random processes are used to select discrete intervals and discrete points,so that the algorithm outputs random and accurate simulation results.Secondly,in order to accurately calculate the time when the ship is overturned,this paper proposes an improved recovery force arm calculation model.At first,the model introduces the time and roll angle into the calculation of the restoring force arm,so that the restoring force arm changes with time and roll angle.The new calculation model can greatly improve the accuracy of the arm.Finally,by the analysis of the force on the surface of the ship,based on the improved random wind and wave frequency simulation algorithm and the improved restoring force arm calculation model,a ship capsizing model under the random wind waves is proposed.The disturbance torque generated by the random wind and wave is compared with the overturning moment to determine whether the ship has been the overturning condition,and simulates the nonlinear roll motion of the hull until the overturning movement process.