强激光辐照下圆柱薄壳非线性振动分析

Nonlinear vibration analysis of thin cylindrical shells irradiated by intensive laser beam

为了研究强激光辐照下的圆柱薄壳的动力响应,运用傅立叶级数展开法导出了强激光辐照下圆柱薄壳的温度场,在此基础上进行了圆柱壳的振动分析,计算中考虑了初始热应力与热软化对其固有频率和振动模态的影响,并与无激光束作用下的情形进行了比较。计算结果表明,激光照射区域产生的材料热软化是导致圆柱薄壳固有频率下降的主要原因。

With the method of Flourier Series Expanding, the temperature field distribution in the thin cylindrical shell irradiated by intensive laser beam is derived. On the basis of it, vibration property of the shell is investigated by using finite element method. Moreover, the effect of initial thermal stress and thermal softening on the shell natural frequency and normal modes is considered in the computation process. Then, the computational results are compared with another case without laser irradiation. Computational results indicate that material softening caused by laser beam will reduce the natural frequency of the thin cylindrical shell.