Simulation Of Large Vessel Berthing Maneuvering

With rapid development of world economy and international trade, the share of goods transited by sea in the entire global transport system is growing. At the same time, in order to reduce transportation costs, the vessels are become larger and larger. With large vessels increasing, not only the maneuverability of the vessel is changed in the harbor, but also the safety of the vessel berthing is greatly affected. Considering the large vessels have big breadth and deep draft, the depth and the width of ports area are limited. While, maneuvering area in the harbor water is not enough, which is unable to meet the requirements of minimum standards by self-vessel operating and causes safety potential of vessel berthing. Meanwhile, as the vessel delivery cycles are gradually shortening, the number of vessels in and out of the port is rising, vessel berthing in the harbor is more frequent and the traffic density is increased. Thereby, the vessel out of port and berthing safety is affected.As the characteristics of large-scale and difficulties of maneuvering in harbor, in order to complete the berthing of large vessels safely and efficiently, during the berthing the large vessels requires tugs, thrusters and other application. Tugs are indispensable tool during the berthing. Thus, comprehensive analysis large vessels manipulation and berthing performance in the harbor, it is very important to simulate berthing of the large vessels under the action of the tug.The work established mathematical model of large-scale vessel motion based on previous studies by absorbing the ideas of MMG ship motion model. The equations of large vessels motion in case of the shallow water and low speed in the harbor are solved with the Runge-Kutta algorithm. The work gives motion characteristics of the large vessel through the quantitative calculation. Then the paper studies interaction between the tug and the vessel and establishes large-scale mathematical model of the vessel berthing manipulate in the harbor tugs assistance.The large vessel stopping process is simulated, and the speed-stroke curve of different initial speeds and different operating conditions are obtained. In the actual manipulation process, the officers and pilot can check real-time speed through the curve to determine whether the ship speed is safety. The paper studies the motion character of the large vessel during the berthing process under the influence of external force. Comprehensive using propeller, rudder and tugs, it achieves the simulation calculation of large vessels'berthing process and proposes control essentials. The research provides a reference data both for the officers to berthing and for the safety assessment of ports and channels.