Research On Ship Shock Environment Under Contact Explosion

Large-scale surface ships inevitably face direct threats from air and underwater anti-ship weapons when conducting maritime operations,such as aerial bombs from the air,anti-ship missiles,and torpedoes and mines from underwater.With the rapid development of these anti-ship weapons,modern naval battles have increasingly higher requirements for the vitality of ships.In order to ensure that wartime ships can have relatively complete combat capabilities,the research on the impact resistance of ship structures and shipborne equipment also appears especially important.In terms of research on the impact environment of ships,the impact environment of ships in far-field non-contact underwater explosions is rich,and its theory is relatively mature,supplemented by real ship explosion experiments and rich numerical simulations.However,the research on the near-field,especially the impact environment of ships exposed to explosions is still scarce,that is,the lack of actual experimental data,and the theoretical aspect is relatively thin.Therefore,it is of great practical significance to study the impact environment of ships in contact with explosions.In this regard,this article starts with the ship’s contact explosion in the air and underwater contact explosion,and analyzes the impact environment of the ship under the impact of the contact explosion and its distribution law.The specific research methods and contents are as follows:(1)First,the basic theories of numerical simulation applied in this paper are combed and introduced,a finite element model of a large surface ship is established,and various analysis conditions are set,and then the ship in the air and water are set separately.Numerical simulations were performed for various conditions of lower contact explosion.The peak pressure of the explosive shock wave in the free field obtained by numerical simulation was compared with the corresponding empirical formula to verify the accuracy of the numerical simulation.Then,the related theories of the ship’s impact environment are introduced,and the concept and calculation method of the impact environment are given,which will lay the foundation for the subsequent analysis of the impact environment of the ship under air contact and underwater contact explosion.(2)Aiming at the specific problem of airborne contact explosions on surface ships,the impact environments of surface contact explosions on the surface ships and the contact explosions in the cabins were calculated respectively.From the perspective of energy transfer,the ships under various working conditions were investigated.The attenuation law of the impact environment with the transfer process provides a certain reference for the study of the impact environment of the ship in the air contact explosion.(3)Considering the threat of torpedoes to large surface ships,the impact environment of different surface ships when subjected to underwater contact explosions was calculated,and the same analysis methods as in the case of aerial contact explosions were used to investigate the effects of underwater contact explosions.The attenuation law of the ship’s impact environment.(4)Based on the basic ideas and principles of the transient statistical energy method,a simple multi-subsystem cabin structure was established,and the energy transfer in the subsystem and the impact environment transfer were calculated theoretically.The angle of statistical energy explains the attenuation of the impact environment when the local energy input of the structure.The research work in this paper has obtained the change law of the impact environment of surface ships under contact explosion,and the results can provide a certain reference for the impact resistance design of ships and shipborne equipment in contact with explosion.