采用单个压电传感器的单模式兰姆波激发频率的选择  

Actuating frequency selection of single mode Lamb waves using single piezoelectric transducer

作　　者：张海燕[1] 曹亚萍[1] 于建波[1] 陈先华[1] 

机构地区：[1]上海大学通信与信息工程学院,特种光纤与光接入网省部共建重点实验室,上海200072

出　　处：《物理学报》2011年第11期377-385,共9页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:11074164,10874110);上海市重点学科项目(批准号:S30108);上海市科委重点实验室项目(批准号:08DZ2231100);上海市教委创新基金(批准号:11YZ17)资助的课题~~

摘　　要：考虑了压电传感器(PZT)与板之间的耦合作用,从理论上研究了单个压电传感器激发时产生单模式兰姆波的频率调节方法,实验给出了模式选择在兰姆波结构健康监测中的应用.在板材、板厚以及PZT尺寸一定的情况下,从理论上能够预测到作为频率函数的各兰姆波模式的幅值变化.根据某特定兰姆波模式的幅值最大而其他模式幅值相对最小时所对应的频率,即可识别出该兰姆波模式优化的激发频率.数值仿真验证了理论的有效性以及单模式兰姆波选择的可能性.在不同的激发频率下,分别激发了优化的A0模式,优化的S0模式以及共存的A0和S0模式用于结构损伤成像.结果表明,单模式兰姆波能够更精确地探测出损伤的位置,显示了模式选择在兰姆波结构健康监测中的重要性.Considering the interaction between the piezoelectric transducer （PZT） and the plate,a frequency adjusting method of generating single mode Lamb waves using single piezoelectric transducer is presented in theory.The application of mode selection in Lamb wave structural health monitoring is experimentally given.The theory has the ability to predict the amplitude of each Lamb wave mode as a function of frequency for given plate material and thickness,and specific PZT size.Optimal actuating frequency can be identified at which the wave amplitude for a particular mode is maximized while the wave amplitudes for other modes are relativelyminimized.Numerical results are presented to validate the theory and show the capability of single mode Lamb wave selection.Different frequencies that correspond to a preferential A0 mode,a preferential S0 mode,and both the A0 and the S0 modes are excited for damage imaging,respectively.The results show that the single Lamb wave mode detection can locate the damage more accurately,demonstrating the importance of the mode selection in Lamb wave structural health monitoring.

关 键 词：兰姆波 压电传感器 激发频率 结构健康监测 

分 类 号：TP212.1[自动化与计算机技术—检测技术与自动化装置]