透镜飞行器击水弹跳运动数值模拟

Numerical Simulation of Lenticular Aircraft during Water-skipping

探索跨介质飞行器水面弹跳过程中的运动特性和自由液面特性,对于跨介质飞行器的着水和弹跳复飞研究有着重要的参考价值。基于无网格粒子数值模拟方法研究透镜跨介质飞行器击水弹跳运动特性及液面变化特性,在与试验值对比的基础上,重点研究不同自旋速度、击水速度和击水角度对透镜飞行器击水弹跳运动特性及自由液面特性的影响。研究结果表明:自旋速度是保证透镜跨介质飞行器顺利实现击水弹跳运动的必要条件,受飞行器自旋速度诱导出现的触水区马格努斯效应会导致飞行器出现侧向运动;击水弹跳过程普遍包括稳定下落、击水、弹跳至平稳飞行三个阶段,自由液面受飞行器强烈冲击出现液面破碎和液体迸溅现象;击水弹跳过程中,飞行器击水速度衰减率及砰击载荷受自旋速度影响较小,主要受击水速度与击水角度影响,击水速度与击水角度越大,速度衰减率及砰击载荷越大。

Exploration of the motion and free water surface characteristics of the trans-media aircraft during the water skipping is of significant reference value for the research on the water landing and skipping re-flight problems.The motion and free water surface characteristics of trans-media aircraft during water-skipping are simulated based on the meshless particle method.The effects of different spin velocities,water-entry velocities and water-entry angles on the water-skipping of lenticular aircraft are studied based on the comparison with the experimental values.It is shown that the spin velocity is crucial to keep the smooth water-skipping for lenticular aircraft.The Magnus effect due to the spin velocity causes the lateral motion of lenticular aircraft.Water-skipping process generally includes three stages:stable fall,impact to water and skipping to smooth flight.The free water surface breakage and water burst phenomenon are caused by the impact from the aircraft.During the water skipping,the velocity decay rate and the impact load are less affected by the spin velocity,but mainly by the entry-water velocity and the entry-water angle.The larger the entry-water angle and entry-water velocity is,the greater the velocity decay rate and the impact load are.