激光冲击波驱动悬臂梁的流-固耦合动力学分析

Dynamic analysis of fluid-structure interaction of cantilever beams driven by laser shock wave

提出采用激光冲击波驱动液体介质中悬臂梁使其产生运动的驱动方式.为了解激光冲击波驱动悬臂梁的运动特性,在统一考虑结构与液体性质的基础上,采用有限元方法,比较了单脉冲激光冲击波驱动真空中和水中悬臂梁的振动输出,并对多脉冲激光冲击波驱动悬臂梁进行了有限元仿真.结果表明:液态介质使悬臂梁振动频率大大降低,衰减加快;在多脉冲作用下,悬臂梁振动幅值在第一个脉冲后有所增大,增幅可达到40%.分析结果显示:在激光冲击波作用下,悬臂梁在其安全范围内可以获得较大的变形量,这表明用激光冲击波驱动悬臂梁可实现符合要求的的运动.

A actuation method was propose, by which the cantilever beam in the liquid medium was driven by laser shock waves. To study the motion characteristics of the driven structure, the vibra- tions of the cantilever beam both in the water and in the vacuum driven by the single pulse laser shock waves were compared by the finite element method. The results show that the vibration frequency of the cantilever beam was reduced obviously and the vibration was weakened quickly in the water. Mo- reover, the vibration of the cantilever beam in the vacuum driven by multiple pulses laser shock waves was also discussed. The results show that the amplitude of the cantilever beam has been increased more than 40 % after the first pulse under the mode driven by multiple pulses laser shock waves. As a result, a large deformation of the cantilever beam can be obtained within the scope of its security, showing that it is possible to make the cantilever beam move actuated by laser shock wave.