船舶碰撞数值仿真的附加质量模型

An Added Water Mass Model for Numerical Simulation of Ship/ship Collisions

根据船舶碰撞的运动滞后和局部损伤特性 ,采用附加质量处理流体 结构耦合作用 ,用详细的有限元模型表达撞击船首和被撞船侧的直接涉撞区结构 ,而将非碰撞区的船体结构视为刚体 ,形成一个附加质量模型用于碰撞仿真计算。附加质量模型不仅建模工作量小 ,而且CPU时间也大大减少。算例表明 ,附加质量模型与流固耦合模型的分析结果具有良好的一致性 ,可以满足一般的工程精度要求。

An added water mass model for using in numerical simulation of ship/ship collisions is introduced. In this model, the effects of water around colliding ships are considered as added masses, only the structural members in bow of the striking ship and in the direct collision zone of the struck ship are represented by fine finite element mesh. A rigid body represents the rest parts of the ship hull. The behavior of structure of local collision zone can well be simulated. The results of collision force and energy absorption obtained from this model have good agreements with that obtained from the fluid structure coupling model. It is verified that the added water mass method required less work on building model and apparently reduced CPU time.