Research On The Technology Of Detecting Ship Target By Submarine Buried Body

Traditional mine has the disadvantage of poor concealment.If it is buried in the submarine sediment,its concealment can be improved,but the target signal needs to pass through the seawater and the submarine sediment before it can be received by mine fuze,it has more energy loss.If the target signal propagates through the ship seismic wave,it has less energy loss.Ship seismic wave field is a new type of physical field,which can be used in the design of new mine fuze and the detection of water surface targets and underwater targets.Under this background,the propagation characteristics of ship seismic waves propagating on the surface of submarine buried bodies are studied in this paper.Firstly,the wave equations of P-wave,S-wave,fluid-solid interface wave and solid-solid interface wave are established.The boundary settings of fluid-solid interface,free surface,fixed interface and artificial section at infinite boundary are introduced.The propagation model of ship seismic wave is established Three dimensional infinite ocean model and geometric model of the submarine buried body are established by ANSYS/LS-DYNA finite element software.Then the ship seismic wave stimulated by low frequency point sound source is simulated.The propagation process of ship seismic wave is simulated.The data of ship seismic wave field are extracted.The P-wave,S-wave and Scholte wave are analyzed and studied.The analysis shows that there are P-wave,S-wave and Scholte wave on the fluid-solid interface,and the velocity of P-wave is the fastest,followed by S-wave,and the velocity of Scholte wave is the slowest.The time-amplitude curves of ship seismic waves in horizontal and vertical directions at different points are obtained by studying the points taken on the surface of submarine buried bodies.Through analysis,it is known that P-wave,S-wave and Scholte wave can be received on the surface of submarine buried bodies.By comparing the amplitudes of P-wave,S-wave and Scholte wave at each point,we can know that the amplitudes of P-wave,S-wave and Scholte wave are the largest at the positive center of the upper surface of the submarine buried body.By comparing the attenuation degree of P-wave,S-wave and Scholte wave,we can see that the attenuation degree of P-wave amplitude is the greatest,the attenuation degree of S-wave amplitude is less than P-wave,and the attenuation degree of Scholte wave amplitude is the smallest.Finally,the simulation results are verified by experiments to prove the correctness of the simulation results.