复合材料圆筒损伤的改进时间反转导波监测

Improved time reversal guided wave monitoring for composite cylinder damage

针对复合材料阻尼较大导致传统概率成像方法存在损伤定位精度较低的问题,提出了基于改进时间反转导波的概率成像方法,并用于复合材料圆筒的损伤监测中。该方法通过在时域内反转压电传感器接收到的响应导波信号,将其记录为参考再发射信号(RRS)。分别在健康和损伤状态下激发相同的RRS信号,重建两种工况下的原始激励信号。将重构信号在健康状态下与损伤状态下的能量比值作为损伤指标,结合现有的概率成像方法实现对损伤的定位和成像。对复合材料圆筒上的模拟损伤开展了试验验证,并与传统方法的损伤定位精度进行了比较。结果表明,改进时间反转法对复合材料结构的损伤具有更高的定位精度及更好的敏感性,验证了该方法在复合材料结构脱粘损伤定位中的可行性和准确性。

A probability imaging method based on improved time reversal guided waves is proposed to address the problem of low damage localization accuracy in traditional probability imaging methods due to high damping of composite materials,and it is used for damage monitoring of composite cylinders.This method reverses the response guided wave signal received by the piezoelectric sensor in the time domain and records it as a reference retransmission signal(RRS).Then,the same RRS signal is excited in both healthy and injured states,and the original excitation signal is reconstructed in both conditions.Using the energy ratio of reconstructed signals in healthy and damaged states as damage indicators,combined with existing probabilistic imaging methods,to achieve localization and imaging of damage.Experimental verification was conducted on simulated damage on composite cylinders,and the accuracy of damage localization was compared with traditional methods.The results indicate that the improved time reversal method has higher positioning accuracy and better sensitivity for damage in composite structures,verifying the feasibility and accuracy of this method in locating debonding damage in composite structures.