基于PVDF梳状换能器的零群速度Lamb波层合板损伤检测的数值研究OA北大核心CSTPCD

In order to improve the accuracy and sensitivity of damage detection in laminated plates,a damage detection method is proposed based on zero group velocity(ZGV)Lamb waves excited by polyvinylidene fluoride(PVDF)comb transducers.The two dimensional time domain finite element method is used to study the excitation of the ZGV Lamb waves by PVDF comb transducers.By changing Young's modulus of the aluminum layer in laminated plates to characterize different damaged degrees,the relationship between the voltage response characteristics of PVDF comb transducers and the damage degree is analyzed.The results show that PVDF comb transducers can effectively excite the ZGV Lamb waves and detect the damaged degree of laminated plates.As the damage degree increases,the ZGV resonance peak amplitude response by the PVDF comb transducers in the frequency domain decreases significantly with decreasing Young's modulus of the aluminum layer,so as to evaluate the change of damage in the laminated plates sensitively.The optimized PVDF comb transducers have advantages in the excitation and reception performance of ZGV Lamb waves,which further improves the accuracy and sensitivity of damage detection in laminated plates.