各向异性板中激光激发Lamb波的数值模拟  

Numerical Simulation of Laser-Generated Lamb Waves in Anisotropic Plates

作　　者：许伯强[1] 陈丽娟[1] 徐桂东[1] 徐晨光[1] 骆英[2] 

机构地区：[1]江苏大学理学院,江苏镇江212013 [2]江苏大学土木工程与力学学院,江苏镇江212013

出　　处：《中国激光》2012年第3期94-99,共6页Chinese Journal of Lasers

基　　金：国家863计划(2009AA03Z107);国家自然科学基金面上项目(11172114);江苏省高校自然科学研究重大项目(10KJA140006)资助课题

摘　　要：基于谱有限元法和模态展开法,针对各向异性薄板,建立激光激发Lamb波的数值模型,得到各向异性薄板中Lamb波沿不同方向传播的色散曲线及Lamb波的传播特性。数值模拟结果表明,谱有限元法能快速有效地计算各向异性板中导波的相速度、群速度,结合模态展开法能够得到任何方向激光激发的Lamb波;Lamb波沿不同方向传播的速度及色散特性与材料的各向异性性质相关。数值模拟为更好地理解复杂介质中导波的传播、指导激励信号的选择及识别检测信号的模态提供了理论依据。Numerical model for laser-generated Lamb waves is established based on spectral finite element method and modal expansion method.The dispersion curves and propagation characteristics of laser-generated Lamb wave propagating along different directions are simulated.The simulation results show that phase velocity and group velocity of guided waves in anisotropic plates can be calculated efficiently by using spectral finite element method.And the laser-generated Lamb wave can be simulated in any direction by combining spectral finite element method with the modal expansion method.Furthermore,propagation velocity and dispersion characteristics of Lamb waves in different directions are closely related to the anisotropy of the material.The numerical simulation provides a theoretical basis for better understanding of the propagation of guided wave,the choice of excited signal and the identification of detected signal in the complex media.

关 键 词：激光技术 LAMB波 谱有限元法 模态展开法 各向异性 

分 类 号：TN249[电子电信—物理电子学] O426.2[理学—声学]