Research On The Damage Characteristics And Armor Protection Of Ship Structure Under The Internal Explosion Load Of The Cabin

In modern marine warfare,naval vessels are the main force in maritime military operations.With the further development of economy,international relations have become more and more delicate,and the arms race has also developed unprecedentedly.When ships are attacked by anti-ship weapons,the damage caused by anti-ship missiles to ships is relatively complex.Firstly,the guidance section of the anti-ship missile guides the anti-ship missile to the ship correctly,and then the warhead of the anti-ship missile contacts the outer shell structure of the ship.The warhead explosion produces instantaneous shock waves and high-speed fragments,which damage the internal facilities and staff of the ship,and even cause fatal damage and damage to the ship.The protective structure on the ship is particularly important to improve its anti-impact damage ability and enhance the vitality of the ship.Therefore,it is of far-reaching significance to study the damage characteristics and armor protection of ship structures under explosive loads in cabins for improving the survival environment of ships in marine warfare and enhancing their operational effectiveness and vitality.Based on the theory of air explosion load and the numerical simulation technology of air shock wave,the numerical simulation method of typical cabin structure is studied in this paper.By introducing grid density coefficient,the dynamic response law of the cabin structure is obtained and compared with the experimental results.The numerical simulation method of multi-Eulerian fluid-solid coupling calculation is determined.On this basis,aiming at the structure of the third compartment,the damage characteristics of the compartment are studied by using the transient dynamic analysis software,and the shock wave propagation and damage characteristics are studied in detail.At the same time,the implosion load is deeply analyzed and a simplified calculation method of the internal explosion load is proposed.The reliability and feasibility of the simplified calculation method are compared and analyzed and the parameters and corresponding formulas of the simplified calculation method are determined.Finally,the cabin structure is strengthened and four kinds of strengthened structures are put forward.Based on the simplified calculation method of implosion load,the protective effect is compared and analyzed,and a protective structure with better impact damage resistance is obtained.The main research contents of this paper are as follows:(1)Finite element numerical simulation technology and its feasibility study.This paperexpounds the relevant theory of dynamic response of ship structure under interior explosion,understands and grasps the mechanism of shock wave action after explosion damage,and combines with the basic theory of finite element software,studies the numerical simulation method of air explosion shock wave,verifies the feasibility of numerical simulation technology,and provides a basis for the subsequent research of dynamic response of ship structure under interior explosion load;(2)Research on simplification of typical cabin structure and calculation accuracy.On the basis of the whole ship model,the typical three-compartment structure is selected.On the basis of the typical three-compartment model,the numerical simulation analysis and calculation of the size of Euler mesh,boundary conditions and coupling surface are carried out respectively.Finally,the finite element modeling standard of the typical cabin structure is determined;(3)Study on dynamic response of ship structure under implosion load.Based on the theory of air explosion,the dynamic response process of ship structure under the explosive load inside the cabin is analyzed,and the propagation law of shock wave under the internal explosive load,the failure mode and the stress,deformation and energy absorption characteristics of the explosive cabin plate structure are obtained;(4)Research on simplified calculation method of implosion load.According to the characteristics of implosion load,the calculation of implosion load is simplified.According to the calculation formula of pressure changing with time under specific equivalent,the dynamic load is equivalent to static load,and the load is carried out according to the characteristics of shock wave propagation.The calculation results of simplified calculation method are further compared and analyzed to verify its reliability and feasibility;(5)Contrastive study on anti-explosion performance of different reinforced structures.In this paper,box girders are used to strengthen the cabin structure of important cabins.Based on typical box girders,three new types of box girders,type I,X and M,are proposed.Simplified calculation method is used to analyze the anti-explosion performance of different box girders under shock wave loads,so as to obtain better anti-impact damage performance of box girders.