失控船拖带系统建模与航迹带模拟研究

Modeling Tug Towing Disabled Ship System and Simulation of Trajectory

基于船舶操纵性运动方程和拖缆的三维动力学运动方程,建立了"拖轮-拖缆-失控船"船舶拖带系统动力学模型,采用数值计算法实现了拖带运动的模拟。拖轮操纵运动模型采用MMG模型,为提高拖带系统建模精度,建模过程中引入了风、浪、流干扰子模块,并采用由试验数据建立的经验公式处理风、浪、流对船舶拖带系统的影响。共分析了无风、浪、流影响,风、浪、流单独影响,风、浪、流联合作用等5种影响状态,并分别进行了模拟计算。模拟结果表明:风对被拖船航迹带的影响相对较小,但拖带系统的漂移较大;流对被拖船航迹带的影响比风的影响大,但相比之下拖带系统漂移较小;波浪对被拖船航迹带的影响最大,航迹带宽约等于被拖船的船长。

Based on ship manoeuvrability theory and 3-demansional dynamics model of towing line, the dynamical behaviour of a towing disabled ship system consisting of a tug coupled to a towed ship through a towline is studied and tug towing is simulated with numerical calculation method. The MMG manoeuvring model is used as the model of tug manoeuvring motion. To improve accuracy of tug towing modeling, the effects of wind, current and second order mean wave drift forces are involved into the mathematical model. Simulation results show that trajectory of towing system changes with different environmental conditions; wind has relatively small effect on tug trajectory and tug towing system draft is bigger; current effect has bigger influence on tug trajectory and tug towing system draft is smaller, compared with wind effect; wave has biggest effect on tug trajectory, the width of trajectory equals to the length of towed ship approximately.