Numerical Simulation Of Local Explosion On Q235 Steel Box Based On ANSYS/LS-DYNA

As the main military force at sea,ships are usually the target of hostile forces.Their anti-explosive research has always been a hot spot at home and abroad.At present,the material of the ship cabin wall is mainly 921 A steel plate,but considering the experimental cost,the equivalent Q235 steel plate is generally used as an alternative.Depending on the type of strike,the warhead's attack on the ship's cabin usually has two types of explosions: one is the explosion inside the cabin of the warhead;the other is the warhead invading the interior of the ship,which is important in steel tanks and pipes.A local explosion occurred near the structure.Aiming at these two kinds of explosion methods,this paper uses Q235 steel as the siding material of the cabin to study the anti-explosion of the structure,and analyzes the failure mechanism under the condition of partial explosion of the indoor chamber and the elliptical cylindrical container steel box in the ship.This paper has done research on the following three aspects:1 The simulation experiment of the solid steel plate in the free field is carried out.The relative error between the calculation and the experimental results is within 10%.The dynamic response process of target deformation is basically consistent with the deformation mode of the fixed support plate.The simulation results are similar to the actual situation.It is determined that the material parameters and algorithms selected by the simulation are applicable to the simulation of the explosion condition.Based on this,in order to study the equivalence of the two materials,the anti-explosion simulation of Q235 steel plate and 921 A steel plate with the ratio of the explosive core distance in the range of 0.445-0.891 m·kg-1/3 was obtained.The relationship between scratching thick.2 On the basis of single wall research,in-depth study of implosion damage of the cabin structure.A reinforced box is designed according to the size of the ship cabin,and the implosion simulation calculation is performed.Compared with the physical experiment,it is found that the deformation mode of the box is consistent with the numerical calculation,and there is a certain error in the final deflection value comparison.The calculation error of the upper plate deflection is 7.8%,which indicates that the simulation results are better;the errors of the side plate and the side stiffened plate are higher.Since the upper and lower top plates are the whole plate,the other plates are connected to the top and bottom plates by welding,and the welding process is not completed,which may cause the wall deflection value of the physical experiment to be high.Finally,based on the experimental results,the optimization of the reinforcement of the siding is given.3 Taking the steel box structure of the elliptical cylinder container inside the ship as the research object,the simulation calculation of the local implosion of the steel box container with the thin-walled convex surface is made.The propagation mode of the shock wave,the failure mode of the wall and the influence of the supporting rib on the anti-explosion process of the box are obtained.According to the analysis conclusion,some improvements and suggestions for the anti-explosion design of the box are proposed.The research methods and research results of this paper can provide reference for the external anti-explosion reinforcement of the ship cabin structure and the external anti-explosion reinforcement of the tank pipe and other structures.