Investigation On The Calculation Method Of Ice-sailing Ship's Ice Load Considering Hydrodynamic Interaction Between Ship And Floating Ice

Global warming and the rapid ice loss in the Arctic make it is possible to exploit fully petroleum resources there.The design of various types of polar navigation ships which have the functions of resource exploitation and transportation has gained more and more attention.Although polar navigation ships will not break the level ice to open the channel,it is possible to collide with the floating ice.Because when the ship closes to the floating ice,they will produce hydrodynamic interference to make the change of ship's movement.Concerning on the issues that once collision happens between ship and the floating ice,it will be likely to cause very serious fortuitous accidents and irreparable loss under the impact stress in a short time.So it is very important for ship safety to study the ice load.The paper investigates on the ice load calculation method of ice-sailing ship collision with the floating ice considering hydrodynamic interaction between ship and floating ice.The main contents of the paper are as follows:1.According to the potential flow theory,the paper derives the boundary conditions of the multi floating body system composed of ice-sailing ship and floating ice.Then the velocity potential based on the surface source method is calculated to get the hydrodynamic coefficients of the ice-sailing ship and the interference force between the multi floating system.In addition,the influence factors of the interference force of the multiple floating body system are studied,and the relationship between the interference force and influence factors is obtained.2.Based on ship maneuverability,the ice-sailing ship motion differential equations in the horizontal plane is established and solved in time domain by Newmark method to obtain the collision angle and location when ice-sailing ship in different speed collides with the floating ice.3.The models of ice-sailing ship and floating ice are established with the nonlinear finite element analysis software ANASYS/LS-DYNA.The ice load is calculated with the explicit analysis method when the ice-sailing ship collides with the floating ice in different speed.At the same time,The safe speed of ice-sailing ship collision with the floating ice is also calculated and hopes to provide a reference for improving safety of the ship and the polar ice resistant design.