【摘要】 采用Lagrange算法开展飞机水面降落的动力学研究。飞机与水体的接触力采用罚函数方法求解。分析飞机入水过程,得到飞机水面降落过程的运动规律以及机身应力波的传递规律,结果表明,降落速度和飞行速度在飞机入水的初始阶段变化较快,随后变化幅度趋于平缓。应力集中先后出现在机尾和机身中部,应力由近及远向机身其他部位传播。最后,应力主要集中在机头部分,该部分应力的传播并不明显。分析不同降落速度的机身结构响应,得到飞机水面降落时结构响应随时间的变化规律。机身结构应力在入水的初始阶段达到最大值,随后迅速下降,最后保持稳定。飞机结构的最大变形也出现在入水的初始阶段,随后迅速回复到初始状态。更多还原

【Abstract】 The dynamics of the airplane impacting on water was investigated.The Lagrange approach was employed to describe this fluid-structure interaction problem.The penalty method was employed to calculate contact force.The movement of airplane after landing was researched by analyzing the head and tail velocities;the structure response after landing was researched by different vertical velocities.The head and tail velocities change rapidly in the initial stage of entering water,then they keep stabilization.The stress wave transfer of airplane during landing was investigated,stress concentration appears at the tail and the middle of the plane successively,the stress transfers to other parts of plane gradually,stress concentration appears at the head of plane at last,its transfer is not clearly.The von Mises stress reaches the peak value in the initial stage,then it decreases rapidly,finally it keeps stabilization.The maximal structural deformation is achieved also in the hundreds milliseconds after landing,and then it relapses rapidly.更多还原