Numerical Simulation Of The Whole Process Of Underwater Explosion Near Warship Based On CEL Method

The territorial sea is an important part of a country.As one of the longest coastline countries,strengthening the development and research of marine protection armaments is imperative for our country,which makes the research work for underwater explosion indispensable.Underwater explosion,in accordance with the explosion distance,can be divided into near-field underwater explosion and medium far-field underwater explosion.As the implement of near-field underwater explosion experimental research is very complex,so the application of numerical simulation is necessary.However,decomposition research methods(divided into shock wave load and bubble load)is applied by most of the traditional numerical methods in the research of underwater explosion,which ignore the continuity and coupling of the underwater explosion load.Moreover,because of the intense load coupling of near-field underwater explosions,the simulation research of near-field underwater explosions is more difficult.So more reasonable numerical methods still need to be studied to improve the near-field underwater explosion simulation accuracy.Firstly,in this study,based on the Euler method,the numerical simulation of the whole process of the underwater explosion in the free field is carried out by using the parameters of the explosive material and the JWL equation of state.The accuracy of the simulated shock wave is verified by comparison with the empirical formula.Then,the method of comparing the simulation results with experimental results is applied to verify the correctness of bubble load simulation.The motion behavior of the bubble load in the pulsation stage and post-jet stage is analyzed.Secondly,the CEL method is used to simulate the whole process of the underwater explosion in the near-boundary interface.The reliability of the method is verified by the method of continuous simulation of near-free surface underwater explosion and near-wall underwater explosion.What's more,the influence of different free surface distance parameters on the dynamic characteristics of the bubble load and the water mound is analyzed.The influence of different wall distance parameters on the jet behavior of the bubble load is analyzed.And on this basis,the post-jet stage bubble motion behavior is analyzed.Finally,from the theory of structural elastic-plasticity,combined with near-field underwater explosion,the simple flat structure encountered near-field underwater explosion is studied.Different dosage of explosive example were set up.And the damage characteristics of the plate structure were analyzed.Then,the numerical simulation of the underwater explosion of complex ship structure is carried out,and the local damage and overall damage of ship structure are given.The main work of this paper is to give a numerical method to study the whole process of near-field underwater explosion.The numerical simulation of the whole process of underwater explosion is studied.At the same time,jet behavior,post-jet stage,and the deformation and damage of elastic-plastic structure in the near-field underwater explosion are simulated and the dynamic response of the complex ship structure to near-field underwater explosion is analyzed.