基于超声导波技术研究了板状结构的损伤检测。理论分析了平板中 Lamb 波的传播特点;利用有限元耦合场模拟方法模拟了平板中 Lamb 波的传播及裂纹对 Lamb 波的影响;根据有限元模拟结果,分析了裂纹尺寸对 Lamb 波传播的影响;为检测损伤的位置,建立了单激发端多接收端的压电阵列;结合概率成像算法,建立了损伤分布场,该分布场的成像结果直观地反映了损伤的位置和严重程度。
Based on ultrasonic guided wave technique ,the damage detection for plates was studied . The characteristics of Lamb wave propagation were discussed herein .With the help of finite element coupling field simulation ,the wave propagation and wave interaction with crack damage of Lamb waves were simulated .From the simulation results ,the affection of crack size on Lamb wave propagation was analyzed .In order to quantify the locations and sizes of the damages ,a single-transmitter multi-receiver PZT array was employed .Combined with probability-based imaging method ,the damage distribution of the plate could be obtained .The imaging results of this distribution can reflect the location and severity of the damage obviously .