厚梁结构中的导波传播与激励频率选择研究  

Study on Propagation of Guided Waves in Thick Beam and the Selection of Excitation Frequency

作　　者：孙学伟[1] 李富才[1] 孙凯[1] 孟光[1] 陈学东[2] 

机构地区：[1]上海交通大学机械系统与振动国家重点实验室,上海200240 [2]合肥通用机械研究院,合肥230031

出　　处：《噪声与振动控制》2011年第6期10-14,19,共6页Noise and Vibration Control

基　　金：国家自然科学基金(11072148;11061160491);国家"863计划"(2009AA044800);机械系统与振动国家重点实验室基金(MSV201110)资助

摘　　要：通过导波在厚梁结构中传播时所表现出的特性,分析导波在厚梁结构中传播的机理。基于Rayleigh-Lamb方程,开发出用于绘制计算Lamb波在各向同性板结构中传播的频散曲线的专业软件。综合考虑在厚梁结构中影响导波激励中心频率选择的各种因素,如:选取适当的导波模式、降低频散效应的影响、增加导波信号的幅值、提高信号时域分辨率和抑制局部对称效应等。基于以上分析优化了激励信号的参数,并提出基于导波的结构健康性监测技术中激励频率选择的标准化流程。Mechanism of guided wave propagation in the thick beam is investigated in this study. Professional software for calculating and drawing the dispersion curves of Lamb waves in isotropic structures is developed by using the Rayleigh-Lamb equation. A number of influencing factors, such as selecting the guided wave modes, reducing dispersion effects, increasing amplitude of the wave signal, improving resolution in time domain, and suppressing the effects of local symmetry, are considered for the selection of excitation frequency. The parameters of the excitation wave are therefore optimized, and a standard process of selecting center excitation frequency in guided-wave based structural health monitoring technique is proposed.

关 键 词：振动与波 导波 厚梁 频散曲线 结构健康监测 

分 类 号：TB559[理学—物理]