Research On The Structural Response And Crashworthiness Of The Ankle Under Ice Load

With the development of modern industrialization,the influence of human activities on the global environment and climate is becoming more and more serious.Some meteorological records show that the global temperature is rising,many of the annual ice sheets in the North and South Poles have begun to melt,and the vast pure land and abundant resources stored in the polar regions have become the focus of attention of all countries in the world.The polar journey of human beings is not only limited to scientific research and investigation,but also gradually develops,which greatly increases the demand of polar ships.The research on the core key issues of polar transport ships represents the level of a countryundefineds ship construction industry,and even restricts the voice of a country,affecting the new pattern of the world.The ports and waterways in the middle and high latitudes are also about to usher in an unprecedented period of prosperity.However,because there are still a large number of ice floes at high latitudes,countries all over the world can not avoid the related problems caused by ice load.If ships collide with these ice floes,once structural damage or oil and gas leakage accidents occur.The consequences are often inestimable.In order to adapt to the bad waterway environment in polar region,the related research on the structural response and collision resistance of bow under ice load is carried out in this paper.This paper mainly focuses on the response of bow structure,studies the finite element simulation technology of ship-ice collision,and puts forward some suggestions for strengthening the collision-resistant structure according to the ship damage situation.The main work of this paper is as follows:(1)The finite element model processing technology of ship is studied,and the bow model is established.The numerical simulation method of ice body at home and abroad is introduced.on the basis of understanding the physical and mechanical properties of sea ice,the constitutive model of sea ice is studied,the material parameters of sea ice are established,and the collision simulation between circular ice and rigid wall is carried out.Then the finite element results are compared with the ISO theoretical curves and experimental values to verify the accuracy of the sea ice constitutive model.(2)At high latitudes,there is usually frozen ice layer or flowing ice platoon floating on the sea surface,thus simulating the collision between the bow and the ice platoon.The control variable method is used to consider the thickness,motion state and physical properties of the ice platoon,respectively.The structural response differences of bow structure damage deformation,ship speed change and collision force under different working conditions are compared and studied.The effects of the above factors on ship-ice collision are obtained,and some suggestions on collision resistance are given.(3)The collision between the bulbous nose of the bow and the ice body is simulated.The structural response differences of damage deformation,collision force and energy change of the bow structure under different working conditions are compared and studied from three angles of ice shape,mass and collision velocity,respectively.The influence of the above factors on ship-ice collision is obtained,and some suggestions on collision resistance are given.(4)In view of the fact that there are many collision accidents between non-icebreaker and ice body,the collision between bow side and ice body edge and ice body plane is simulated,and the influence of ice body height change on side collision is discussed,and the structural damage and deformation are analyzed and compared.The structural response of each structure of bow and collision force is summarized,and the failure mode of bow structure is summarized,and the suggestions of collision resistance are given.