实尺度船舶参数横摇数值模拟研究

Numerical Study on Parametric Roll of Full-scale Ship

船舶在特定波浪环境下会遭遇大幅度的参数横摇运动。论文基于黏性流理论建立CFD数值模拟方法,结合动态重叠网格技术与刚体6自由度运动预报模块,对国际标准水面船模型ONRT,在横摇、纵摇与垂荡3自由度耦合运动情况下进行实尺度参数横摇数值模拟。还在安装不同附体(舭龙骨、呆木、尾舵)的条件下进行参数横摇数值预报。研究结果表明,加装舭龙骨对参数横摇具有显著的抑制作用,而呆木与尾舵虽然能在一定程度上减小参数横摇幅值,总体而言效果不显著。研究成果对船舶第二代完整稳性衡准的研究具有一定的参考意义。

As a ship is advancing in a certain wave condition, the parametric roll may occur with a large amplitude.Therefore, it is of importance to develop the numerical method aimed at simulating this nonlinear stability failure mode and predicting the parametric roll. In this study, a viscous CFD method, coupled with dynamic overset grid approach and rigid-body 6 DOF motion prediction module, is performed for the prediction of the roll-pitch-heave motions of the full-scale ONR Tumblehome. The systematic verification and validation studies are first conducted to quantify the uncertainty and prediction difference during the full-scale simulation. The parametric roll of the ONR Tumblehome appended with different appendages(bilge keels,skeg, and rudder) is then simulated to study the effect of the appendages on the parametric roll. The results indicate that the bilge keel shows significant effect to restrain the occurrence of the parametric roll but the effects of the skeg and rudder are not obvious. This study can provide a reference for the research of second-generation intact stability criteria.