Research On The Simulation Of Ship Towing System

Based on the MMG's separated modeling theory, and the catenary model of towed cable, the paper established the 3-DOF manoeuvring motion equations of towing system which consists of towing ship and towed ship connecting with cable. The effects of wind, wave, current and shallow water on the towing system was considered in these equations.The numerical solution of the manoeuvring motion equations was calculated through the Runge-Kutta method. From the calculated results, the thesis analysed the factors which affect the tension of towed cable, and the towing system's stability under the influence of cable length. By calculating the turning motion, the large-range maneuverability of towing system was discussed. Then, the effect of cable resistance on towing system was investigated.According to the mathematical model of towing system, with Viscual C++ 6.0, the 2D numerical simulation program of towing system was made. With the PID control, this program realizes the prediction of maneuverability of towing system. The simulation program is helpful to explore the rules of manoeuvring motion of towing system, and can give guidance to the manoeuvring control of towing system.