A Study On Impact Response Similarity Of Titanium Alloy Plate Under Underwater Explosion Shock Wave

Titanium alloy,a structural material for ships,has important research value in its dynamic response under the impact of underwater explosions.The impact response of the fixed-back hollow circular plate is one of the methods to study the ability of ships to resist underwater explosive impact.It is an essential basis for the design of new ships.The equivalent loading device of underwater explosion shock wave has been proved to be an effective way to study explosive shock wave in the laboratory after continuous research and improvement by many scholars.With the help of the equivalent loading device of underwater explosion shock wave,this paper uses an analysis method combining theory,experiment and simulation to explore the similarity of impact response of titanium alloy plate under the action of underwater explosive shock wave.The main research contents of this paper are as follows:1.The similarity theory model of titanium alloy plate under the action of underwater explosion shock wave is established through similarity theory.Combined with the theoretical relationship of the equivalent loading device of underwater explosion shock wave,the velocity similarity coefficient of the flyer plate in the similar theoretical model is corrected,and the correlation between the velocity similarity coefficient of the flyer plate and the underwater shock wave attenuation coefficient is discussed.2.The static tensile test and dynamic compression test were performed on the titanium alloy respectively.The strain hardening coefficient and strain rate hardening coefficient of the titanium alloy constitutive model were obtained by fitting the experimental results,and the J-C dynamic constitutive model of the titanium alloy material was established.3.The numerical simulation of the equivalent loading device of underwater explosion shock wave is carried out by using AUTODYN finite element simulation software.The change of the velocity of the flyer,the thickness of the flyer,the thickness of the piston,and the materials of the flyer and the piston cause the change of the peak attenuation coefficient of the shock wave in water to be explored by simulation.The relationship between the velocity of the flyer plate and the attenuation coefficient of the shock wave in the water is studied,and the revised velocity similarity coefficient of the flyer plate is achieved by combining the theoretical formula of the similarity coefficient.4.Based on AUTODYN,a finite element simulation software,a similarity model of titanium alloy plate under the action of underwater explosion shock wave was established.Through the comparison of theoretical and simulation results,the validity of the similarity coefficients of physical quantities in the modified similarity theoretical model of equivalent loading device for underwater explosion shock wave was proved.With the shock wave intensity and the thickness of the titanium alloy plate as variables,the plastic deformation law of the titanium alloy plate under the action of the shock wave intensity of the underwater explosion was explored from the initial movement speed and displacement of the deformation of the titanium alloy plate.