Research On Collision Response Of Cylindrical Pressure-resistant Structure

With the rapid development of the world economy today,energy shortages have become the economic factor most concerned by governments.Today,as the energy output of traditional oil producing areas is weakening,many countries have turned their eyes to the vast ocean.With the development of modern civilization,people are speeding up the development of the ocean,from the offshore to the distant sea,from the shallow sea to the deep sea.As a powerful tool for human beings to understand the ocean,develop the ocean,and protect the ocean,the submersible plays an important role.As a hot issue in the field of ship and ocean engineering,collision is the most common accident during the navigation of a submersible.Because of its small reserve buoyancy and the presence of external hydrostatic pressure,the collision of submersibles is more dangerous than the collision of surface ships.Based on the above reasons,this paper studies the collision response of cylindrical pressure-resistant structures.Through the finite element simulation technology,the collision research of the submersible is divided into two parts: water surface collision and underwater collision.The influence of different collision parameters on the response of the cylindrical toughness structure under different targets is analyzed,and the water surface and underwater collision are observed.The lag characteristics found were relatively studied.The main research work is as follows:(1)Inductively organize the external/internal collision mechanics of the submersible,and introduce the key techniques in the numerical simulation of ANSYS/LS-DYNA.The fluid treatment method in the process of submersible collision is summarized,and the attached water quality coefficient of the submersible water surface and underwater navigation operation is determined.(2)Based on the theoretical basis,the unit type,grid size and material parameters are determined,and the numerical simulation of the collision problem of cylindrical pressureresistant structure is carried out.(3)For different working environments of submersible water surface/underwater,select different collision targets(reefs,concrete buildings,ship side,silt,steel submersibles of the same specification)to study different collision parameters(collision angle,Impact of impact velocity and external hydrostatic pressure on the collision response of cylindrical pressureresistant structures.The time series results of collision force,energy change,damage deformation and stress and strain are obtained,and these results are compared.(4)During the research,the rigid body motion hysteresis and local damage deformation of the submersible were found,and the hysteresis characteristics were studied.The factors affecting the rigid body motion hysteresis and local damage deformation of the submersible were obtained.