复杂流态下系泊船的水动力特性研究

Study on hydrodynamic characteristics of moored ship in complex flow regime

为研究复杂流态下系泊船的水动力特性,在最佳系缆方式未知的情况下,通过约束船舶横荡、纵荡、艏摇三个方向的运动近似替代缆绳的约束作用,建立系泊船简化模型。在完成网格无关性和数值方法可靠性验证的基础上,对常规流态以及复杂流态下系泊船的粘性流场进行数值模拟,分析系泊船水动力系数和运动响应的变化规律。结果表明:随着水流流速的增大,纵向力系数变化受到水流流向角的影响明显,横向力系数及艏摇力矩系数变化较小,垂荡、纵摇、横摇增大;随着水流流向角的增大,纵向力系数变化较为复杂,横向力系数增大,艏摇力矩系数先增大后减小,垂荡、纵摇、横摇增大;复杂流态下和一定流向角水流下系泊船的水动力系数和运动响应较为相似。

In order to study the hydrodynamic characteristics of a moored ship in complex flow regime,a simplified model of a moored ship was established by restraining the motion of the ship in the three directions of sway,pitch and yaw to approximately replace the restraining effect of the rope when the optimal mooring mode was unknown.Based on the verification of grid independence and reliability of numerical method,the viscous flow field of moored ship under conventional and complex flow regimes was simulated,and the variation of hydrodynamic coefficient and motion response of moored ship was analyzed.The results show that:with the increase of flow velocity,the change of longitudinal force coefficient is obviously affected by the flow direction angle,the change of transverse force coefficient and yaw moment coefficient is small,and the heave,pitch and roll increase;with the increase of flow direction angle,the change of longitudinal force coefficient is more complex,the transverse force coefficient increases,the yaw moment coefficient first increases and then decreases,and the heave,pitch and roll increase;the hydrodynamic coefficients and motion responses of the moored ship are similar under complex flow regime and certain flow direction angle.