Research On Damage Characteristics Of Hemispherical Shaped Charge To Typical Submarine Structure

In order to effectively improve the damage capability of underwater weapons to moderm warships,modern weapons have been developed from conventional blasting warheads to shaped warheads on the basis of improving the guidance accuracy and hit probability of underwater weapons.Based on the summarization of the present researches and damage characteristics of underwater weapon in the shaped charge,numerical models of double-armors,composite armor and typical double-shells submarine cabin were established in this paper,and their dynamic responses and damage characteristics subjected to the underwater explosion load of hemispherical shaped charge were studied to provide a reference for damage assessment of the submarine structure attracted by shaped water weapon.Firstly,the research content and method in this paper were put forward according to the present research of underwater weapon in the shaped charge and the damage characteristic of shaped warhead,meanwhile,the relevant theoretical background of SPH-FEM(Smoothed Particle Hydrodynamics-Finite Element Method)and Coupled Euler-Lagrange(CEL)algorithms were illustrated in details.By comparing the algorithms’ numerical results with the experimental data,the numerical algorithms adopted in this paper were completely verified to effectively deal with the problem of shaped jet damaging on the typical submarine structure.Secondly,based on the theory of compressible fluid dynamics,the process of the detonation of hemispherical shaped charge and the shaped jet formation were numerically simulated with the SPH method.By coupling the SPH and FEM,based on the plastic dynamics,the process of shaped jet penetrating double-armors structure in the air was numerically simulated as well as the load and damage characteristics of the shaped charge in different fluid media,then it was affirmed that the damaging effect of the shock wave on the structure needs to be considered while researching the load characteristic of shaped charge exploding under the water.Thirdly,the damage process of composite armor structure subjected to the near-field shaped charge underwater explosion load was numerically analyzed to evaluate the after-effect damage capability of the shaped jet.During this process,the CEL method is used to simulate the penetration of shaped jet on composite armors while the Coupled Acoustic-Structure method is selected to simulate the shock wave action.Comparing the numerical results of these two loads imposing the composite armor structure,the damage mode of the structure subjected to both the shaped jet and shock wave is obtained and the validation of this numerical method is gotten according to the comparative results with numerical and experimental data.Finally,choosing the typical double-shells submarine cabin as the research object,and the process of submarine cabin damaged by underwater explosion shaped jet is simulated by using the CEL algorithm.Regarding the numerical damage results as the initial conditions of calculating the shock wave load,then the damage result of submarine cabin is obtained with the Coupled Acoustic-Structure method.Besides,the damage characteristics of the submarine cabin under the near-field shaped charge underwater explosion were numerically analyzed by combining with the shrinkage test method,which aims to provide a reference for the damage analysis of submarine structure attacked by the underwater weapon of shaped warheads.