A Numerical Simulation Of Explosion Loads And Bull Response

The process of ships being subjected to the TNT explosion load is very complicated,and the explosion load may cause great damage to the ships.The far-field explosion mainly causes the elastic response or local plastic deformation of the ship structure,and the near-field explosion can cause the hull to break,which may lead the hull to turn over.Therefore,it is important to study explosive loads as well as the structural response.The main research contents of this paper are as follows:Firstly,the research status at home and abroad is described from three aspects: theoretical method,experimental method and numerical method,and the main content of this paper is clarified.Secondly,the Ansys/Ls-dyna software is used to study the airborne explosive load and the superstructure response.The effects of grid size and explosive equivalent on the peak value of shock wave overpressure are discussed.A finite element analysis model which can effectively simulate the external explosion of the superstructure is established.The distribution law of pressure load on each end of the superstructure is obtained,and the LR empirical formula is proposed.Then the fluid-solid coupling method and dynamic response analysis method are used respectively.Numerical simulations are presented to discuss the applicability of the two methods for simulating the response of superstructures under simulated blast loads.Thirdly the internal blast load and its structural response were studied by Ansys/Ls-dyna software.The system examines the parameters of the superstructure space volume,TNT equivalent,and explosive center position,and the influence of the explosion shock wave propagation law and the center load of each end face of the superstructure.The Ls-dyna software was then used to simulate the structural response and failure mode of the cabin structure under internal blast loads.Finally,the underwater explosion load and structural response were studied by Ansys/Ls-dyna and Abaqus software.The underwater shock propagation process of the explosion shock wave is simulated,and the influence of explosive equivalent on the peak pressure of the shock wave is discussed.For the shortcomings of the Ls-dyna calculation in the far-field underwater explosion,the TNT equivalent mass method is recommended.Then based on the Abaqus software,the dynamic response of the surface ship structure under the underwater explosion load was simulated by the acoustic-structure coupling method using the Geers-Hunter model.