Dynamic performance of towing system-simulation and model experiment

Numerical simulation and model experiment are introduced in this paper to study the dynamical behavior of a towing system consisting of a tug coupled to a tow through a towline. The MMG maneuvering model is used as a basis to develop a dynamical nonlinear model of towing system in the presence of sea current, wind and waves. Based on the model motions of two towing systems, a 8820t deck barge-1940 KW tug as well as a semi-sub barge “1940 KW tug have been studied. Scale model experiments of 8820t deck barge-1940 KW rug system have been performed and experiments data about motions of twelve-DOF towing system and towline tension have been obtained. Using these methods, the affection of disturbance, parameters of towing design, such as loading condition, towline length and towing speed to the course stability of routing system is analyzed. Finally, the results of `Single Towed Vessel Model´ `Towing System Model´ and scale model experiment are compared. It is concluded that the `Towing System Model´ presents the best results to the observation of real operation and same suggestions for further study are made