Laser-induced vibrations of micro-beams under different boundary conditions
Laser-induced vibrations of micro-beams under different boundary conditions
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DOI：
10.1016/j.ijsolstr.2007.11.006
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发表时间：
2008-04-01
影响因子：
3.6
通讯作者：
Soh, Ai Kah
中科院分区：
文献类型：
--
作者：
Sun, Yuxin;Fang, Daining;Soh, Ai Kah
本文研究了脉冲激光加热微梁时的振动现象。该光束由硅制成，并由脉冲持续时间为2 ps的非高斯激光束加热，该激光束由于热弹性阻尼效应而激发振动。温度场和应力场的耦合作用导致能量耗散，机械能转化为热能，这是不可逆的。采用基于拉普拉斯变换的解析-数值方法计算了振动中的挠度和热力矩。提出了一种通用的拉普拉斯反变换算法。通过与FEMLAB软件包数值计算结果的比较，验证了该算法的有效性。研究了激光脉冲能量吸收深度的影响。分析了尺寸效应和不同边界条件的影响。最后比较了空气阻尼和热弹性阻尼对梁的阻尼比和共振频率的影响。(c)2007爱思唯尔有限公司保留所有权利。
In this study, the vibration phenomenon during pulsed laser heating of a micro-beam is investigated. The beam is made silicon and is heated by a non-Gaussian laser beam with a pulse duration of 2 ps, which incites vibration due to the thermoelastic damping effect. The coupling between the temperature field and stress field induces energy dissipation and converts mechanical energy into heat energy, which is irreversible. An analytical-numerical technique based on the Laplace transform is used to calculate the vibration of the deflection and thermal moment. A general algorithm of the inverse Laplace transform is developed. The validation of this algorithm is obtained through comparison with numerical results obtained by the FEMLAB software package. The effect of laser pulse energy absorption depth is studied. The size effect and the effect of different boundary conditions are also analyzed. Finally, the damping ratio and resonant frequency shift ratio of beams due to the air damping effect and the thermoelastic damping effect are compared. (c) 2007 Elsevier Ltd. All rights reserved.