中文摘要：

水陆两栖飞机水上降落属于复杂的流固耦合问题，文中建立了某水陆两栖飞机机头的入水流固耦合模型，采用耦合的欧拉一拉格朗日（CEL）算法分析了机头入水瞬时的结构动力响应，对比了不同入水角度和不同垂直速度下机头的应力、冲击力及质心速度变化．结果表明：机头入水初期船底冲击力即出现峰值，之后随着机头抬高，船底冲击力将再次出现峰值；入水过程中机头骨架受力变化明显；随着入水角度的减小，机头应力也减小；入水速度减小，机头应力和船底冲击力都随之减小．

英文摘要：

Aiming at the water landing of amphibious aircrafts, this paper presents a fluid-structure interaction （FSI） model of a certain amphibious aircraft head and analyzes the transient structural dynamic response of the head ditching by using the coupled Eulerian-Lagrange （CEL） method. Moreover, the stress, impact force and mass center velocity of the head at different ditching angles and vertical speeds are discussed. The results show that （ 1 ） the bottom pressure peak appears in the initial ditching stage and appears again with the heading up of the air- craft head; （2） during the ditching, the pressure of the head skeleton changes significantly; （3） with the de- crease of the hitting angle, the stress of the head reduces ; and （4） both the head stress and the bottom impact force reduce with the decrease of ditching speed.