Research On Simulation Analysis Of Collision Between Fishing Vessel And Wharf

With the development of shipping economics, the number of merchant ship and cargo vessel continues to increase, while fishing vessels also continue to increase all the time. The port scale has been expanding, and berths are more and more. Meanwhile, due to large base of Chinese fishing boats and their working characteristics, higher frequencies their port entry and exit, these all potentially increase the risk of collision about fishing vessel and wharf’s end, making collisions happen occasionally. Fishing vessel accidents in nearly 60 percent are caused by the collision. Therefore, it’s particularly necessary to development the research on fishing vessel collision. Making collision of the 42 m fishing vessel and wharf as a example,establish a finite element model about collision by MSC.Patran/Dytran software. Properties about bow collision of fishing vessel, energy-absorbing of bow structures and structural crashworthiness characteristics were analyzed.In terms of collision characteristics about fishing vessel bow, use the finite element model simulate the course of collision between fishing vessel and wharf and obtain deformation of collision damage, collision force curve, energy conversion curve, velocity curve, picture of effective plastic strain, effective stress and displacement between fishing vessel and wharf. By analyzing the results,the damage of fishing vessel and wharf in the collision mainly focuses on the area of collision contact, so bow of fishing boat is its major injury area. Fishing vessel’s stiffness is smaller than wharf’s stiffness, so wharf’s damage is small in the collision damage; kinetic energy of fishing vessel in collision is mainly converted to deformation energy, then other kinetic energy is converted to hourglass energy and friction energy; also analyzing the effects of different speed to fishing vessel collision, the greater the speed, the greater the collision damage, deformation damage of fishing vessel bow is suffered more serious.In terms of fishing vessel structural crashworthiness about bow, firstly analyze the energy absorption of various structural components in bow and draw that outer plate is the main energy-absorbing component, then is the transverse frame, deck and longitudinal frame. Kinetic energy of fishing vessel in collision process is mainly converted into deformation energy of outer plate; secondly analyze the impact of bow structure variables to structural crashworthiness of bow, and draw that increasing thickness of outer plate improves the crashworthiness of bow structure, but simply increasing the thickness of outer plate is not economy and should combine transverse frame and deck with it to consider. Reasonable thickening component can improve crashworthiness of bow structure, but also indirectly shows quality is influential to the collision; concluding with the additional V-bulwarks structure, by analysis and comparison of the results with original ship, additional V-bulwarks structure makes structure damage of original bow reduced greatly. Additional V-bulwarks structure absorbs 48.37% energy, and energy absorbed of original fishing vessel outer plate, transverse frame, deck is greatly reduced by 27.79%, 13.26%, 7.72%, playing a good role in protection to the original bow; contrasting additional V-bulwarks structure and structural components thickened shows that specific energy consumption of bow with additional V-bulwarks structure, which is 498.99J/kg, is minimum and improve crashworthiness of bow structure, protecting bow to reduce the damage, which is much more effective method.