Research On Key Technologies Of No-power Vessles Towing In The Harbor

With the continuous development of the shipping industry, the constant speed of ocean development and port construction, no-power vessels towing operation has become an indispensable part of the shipping industry, and navigation-scale, navigation standards and towing methods has become the point that many scholar, engineer and MSA focus on.Towing operation in the harbor is different from the sea towage:the harbor towing and marine towing in different ways; harbor navigable waters is relatively narrow, navigable depth is shallow, and intersection with ships in or out of the harbor is more frequently, therefore, through research on navigation-scale, navigation standards and towing methods has great significance to guarantee the harbor towing operation, the security of the port waters. Operations research for more towing at sea, including the offshore towing operations, marine engineering facilities, towing the ship out of control, but no-power vessel from the berths to anchorage has little research.This article first analyzes no-power vessels maneuvering characteristics and stability. Using ship maneuvering equations of motion derives ship's maneuverability index, according to the ship's hull and the influence factors to ship's maneuverability index obtains maneuverability characteristics of no-power vessels; calculating ship's stability and the shake cycle based on relevant experience formula, no-power vessels are hypertrophic shallow draft vessels is taking into account proposes the suitable formula to determine the shake cycle.Then navigation-scale of no-power vessel towing were analyzed and calculated. The towing system as a whole, based on the analysis of the rotary movement of the ship obtains the cyclic motion model of no-power vessel; built the safety under keel clearance (UKC) model, used computer programming to achieve calculating UKC quickly; based on the impact on navigation of wind and current, the width of tugboat and towed-ship is made the ship's width, and then calculate the towing width of the channel.Then formulate the towing methods according to the characteristics of the towing in the harbor, based on calculation of the towing resistance and principles of mechanical, analyze towing programs and tug configuration, and further to determine towing speed.This article also analyzes factors affecting the safety of towing operations, they are the tug conditions, towed-ship conditions and navigation conditions, proposes towing standards and precautions.Reseach on key technologies of no-power vessles towing in the harbor can solve the urgent problems which are towing methods, navigation-scale, towing-speed and tug using, while further enriches and improves towing theory, and finally protects towing operations and other vessels safe.