Study On Damage Effects Of Warhead Close Explosion Load On Liquid Cabin

Under the condition of modern information warfare,large surface warships are facing increasingly severe damage threats with the improvement of the anti-ship missile’s strike accuracy.When the semi-armor-piercing missile penetrates broadside of warship and explodes inside,the high-strength shock wave and high-speed fragments will cause a devastating impact on the structure and personnel of the warship,and seriously weaken the combat effectiveness of the warship.In view of this,at present,the multi-layer protection system is often used by large surface warships to reduce the damage degree caused by the explosion of the weapon warhead.As an important part of the multi-layer protective system,the liquid cabin’s protection ability for the warhead load directly affects the defense effect of the whole system.In this paper,the damage process of the liquid cabin under the interaction of fragments and shock wave is analyzed by combining experiment,numerical simulation and theoretical analysis.The purpose is to reveal the damage mechanism of the coupling load on the liquid cabin,propose the protection idea of the composite liquid cabin,which can provide a reference for new warship protective liquid cabin design.The major research work is as follows:Numerical simulation is carried out for the explosion process of semi-preformed fragment warhead,and the influence of boundary conditions and grid density on the calculation results are discussed by establishing the comparative model.Meanwhile,the detonation wave propagation characteristics and the scattering characteristics of the fragment under different initiation manners are analyzed.Compared with the theoretical and experimental results,the reliability of the modeling method,material model and related parameter setting are verified,which can provide accurate input load for the subsequent liquid cabin response.On the basis of the above research,the scaling model of liquid cabin and warhead are designed,the traditional liquid cabin and composite liquid cabin are experimentally tested under the blast load of cased charge.Combined with the numerical simulation,the shock wave propagation process,wave impedance mismatch phenomenon and failure mode in the damage process of the liquid cabin are analyzed in depth,the excellent protection mechanism of the composite liquid cabin is revealed preliminarily.In view of the scattering characteristics of fragments during warhead explosion,the shock wave effect and structural response characteristics of multiple fragments hitting the liquid cabin at high velocity are studied.The effects of the number of fragments,the distance between fragments,the time interval between impacts and the incident angle on the damaging effect of the liquid cabin are discussed,which can provide the theoretical basis for the optimal design of the liquid cabin structure.The process of the fragment penetrating liquid medium is analyzed in depth,the velocity attenuation characteristics of the fragment in water with different head shape coefficients are analysed,and the drag coefficient is related to the real-time velocity of the fragment.The velocity attenuation program of the fragment is written.At the same time,considering the influence of the shape parameters of fragment,the shock wave process formed by the fragment entering water is theoretically deduced in detail.The program for calculating shock wave pressure is written,which can provide input load in the process of liquid cabin design.