Evaluation Of Damage Effect Of Dynamic Explosion Load On Cabin Structure

With the rapid development of high speed and ultra-high speed anti-ship weapons,the residual velocity of warhead is gradually increased after entering the cabin through armour.Under the influence of charge velocity effect,the distribution characteristics of explosive load in the explosive compartment in the combat department are obviously different from the static explosion in the explosive compartment,thus changing the damage effect on the compartment structure.The existing evaluation of cabin damage effect under static explosion condition can no longer accurately measure the damage of cabin structure under dynamic explosion condition of charge,so it must be combined with the residual velocity of warhead after armor piercing into the cabin to make comprehensive analysis.In order to study the dynamic critical load of cabin structure damage evaluation,this paper adopts theoretical analysis,numerical simulation and data fitting method,from the dynamic critical load characteristics and cabin structure damage features and regularity and cabin structure damage effect evaluation from three aspects,has realized the cabin structure under the action of the dynamic critical load damage effect of rapid assessment,can provide the warheads chamber blasting damage assessment and provide certain support ship resistance implosion structure design.In order to accurately simulate the damage effect of cabin structure under dynamic explosion load,the fluid-structure coupling algorithm in finite element analysis software Auto Dyn was used,combined with relevant empirical formulas and test data,the mesh division method in simulation calculation was discussed,and the mesh size suitable for the simulation of dynamic explosion damage effect in the charging chamber was obtained.The reliability of the simulation method for the damage effect of cabin structure under dynamic explosion load is verified by using relevant test data and empirical calculation formula.The results show that the numerical simulation method can accurately simulate the damage effect of dynamic explosion load on cabin structure,and can be used in subsequent simulation research.Based on the purpose of studying the characteristics of dynamic explosive load in cabin,the characteristics of incident stage,reflection stage and quasi-static stage of dynamic explosive load in cabin are studied according to the propagation process of dynamic explosive load in cabin by means of numerical simulation.The results show that the dynamic detonation load has obvious directionality in the incident and reflection stages under the influence of charge velocity.In the quasi-static stage,the contribution of charge velocity to the increase of quasi-static pressure is small,and the influence of quasi-static pressure can be ignored when the charge is moving at low speed.Therefore,it can be considered that the forward charge movement is more serious under the influence of the charge movement speed.Based on the purpose of studying the damage characteristics and rules of cabin structure under dynamic explosion load,the sensitivity of each bulkhead damage effect to charge motion speed and the damage rules of cabin structure under dynamic explosion load were discussed by changing a lot of simulation conditions of charge equivalent and charge motion speed.The results show that the damage effect of positive and negative bulkhead is sensitive to the speed of charge movement,and the speed of charge movement will aggravate the damage effect of forward bulkhead and weaken the damage effect of negative bulkhead.According to the failure modes of positive and negative bulkheads of charge movement,the damage effects of cabin structure under dynamic explosion load can be divided into five asymmetrical failure modes.Based on the purpose of evaluating the damage effect of cabin structure under dynamic explosion load,the dimensional analysis method was used to conduct parameterization analysis on the simulation results,and the dimensionless expression of the overall asymmetric failure mode of cabin and the rapid evaluation and prediction interval were derived.Using numerical simulation data and data fitting method,the calculation formula of dynamic explosion impact load in cabin was obtained.Taking the limit velocity of bulkhead as the damage criterion,the evaluation model of damage effect of dynamic explosion load on cabin structure was established.A program for evaluating the damage effect of dynamic explosion load on cabin structure based on dimensional analysis and numerical calculation is written by C++ language.The program is verified by an example calculation,and it is considered that the program can be used to evaluate the damage effect of cabin structure under dynamic explosion load.