Ship Ice Water Coupling Technology And Ship Ice Collision Model Test Research

With the rapid development of economic construction in our country,marine economy has become a new growth point of national economy.The development of the Arctic and the opening of the Arctic channel will provide new protection for our new strategy.However,with the large-scale development of marine development,sea ice disaster that affects the safety and operation of marine structures,interaction between sea ice and structure has become increasingly prominent problem.Although China is a country near the north pole and the world shipbuilding powers,but in the polar marine core key basic research is still very weak,which is the important reason to restrict China's polar ship construction capacity to enhance.This issue has aroused the attention of our government and academia,so experts have focused on the polar crude carrier and the polar deck transport ship.At present,for the study of ship-ice collision,most scholars have considered the water medium as additional quality,and did not use the fluid-solid coupling method.However,the hydrodynamic effect of surrounding water plays an important role in the analysis of ship-ice collisions,It is important to take into account the effect of water when dealing with the absorbed energy in collision.Based on the above reasons,on one hand,it is necessary to carry out ship water ice coupling technology research.On the other hand,it is necessary to carry out the research on the collision model of shipboard and ice and the response of ship-ice collision structure,which is important for improving the structural safety of polar ships.This is the core of the key issues that need to be solved of polar ships.The main works of this paper are as follows:(1)Ice material model is built.To collect the data of mechanical constitutive relation of ice body in polar region,such as compressive strength,tensile strength,shear strength,flexural strength,and thickness?density and other physical properties.Based on the study of the constitutive relation of the ice material by scholars,considering the characteristics of the ductile brittleness during the crushing process,a more accurate ice material is constructed by applying the numerical simulation method to study the ship-ice collision problem.(2)The numerical simulation model is studied.According to the established constitutive model established by LS-DYNA,the numerical simulation of the collision process between the ice body and the steel plate in the water medium is taken into account.The ice load is compared with the pressure-area curve under the iceberg collision load recommended by the International Standardization Committee in ISO / CD19906(2010)to verify the accuracy of the ice material.The constraints and contact definitions are determined,etc.,In order to achieve the ship water ice coupling technology.(3)Experimental study on the collision test of hull plate frame and ice body in water medium is carried.According to the principle of similarity,design and make steel plate frame model,do a experimental study on the model of collision between hull plate and ice body in ice pool.The dynamic acceleration of ice body and plate frame is measured.According to the above numerical simulation of the ship and ice collision,we establish the same frame and ice model as the same as the model test.By comparing the model test results with the numerical simulation results,the accuracy of the numerical simulation method of ship-ice-water collision is verified,Which is the foundation for the simulation study of collision between ship and ice.(4)Study on response of ship-ice collision structure in water medium.This chapter chooses the bow of the polar ships as the object of calculation.The structure response of a three-dimensional ship bow and ice body collision is studied through a fluid-solid coupling algorithm,and combined with the nonlinear finite element software LS-DYNA to study the collision between the bow with the different mass of ice,the bow with the same quality of different angles of the ice,different speed ship with the same quality of the ice under the ship ice collision structure response of various schemes.The simulation results are compared under various schemes considering fluid-solid coupling without considering fluid-solid coupling,It reveals the features of the ship deformation,energy absorption,impact force,speed,and the influence of the water medium on the collision of the ship and ice under various programs.Finally it can provide reference for the design of the impact structure of the polar transport ships.