基于碳纳米管薄膜电学成像的复合材料结构损伤识别研究

Damage Detection for Composite Structures Using Carbon Nanotube Film and Electrical Tomography

随着纳米技术的飞速发展,碳纳米管因其良好的自感应能力逐渐被应用在结构健康监测领域。提出将碳纳米管薄膜布置在复合材料结构表面作为智能感知层,结合电学成像方法,根据碳纳米管薄膜边界电压值的变化,重建损伤引起的电导率变化分布图像,以确定损伤情况。为提高电学成像效果,采用基于L1范数正则化的最小二乘法重建电导率变化分布,并利用L曲线法选取适当的正则化参数,结合内点法进行反演。搭建了电学成像测试系统并进行了实验研究,实验结果验证了本文所提出方法的可行性和有效性。

Along with the rapid development of nanotechnology,structural health monitoring（ SHM） technology based on carbon nanotubes（ CNTs） has been developed with CNTs＇ excellent self-sensing ability. This paper proposes a new method to superpose CNT film on the surface of composite structure as smart sensing skin,and to indicate the damage information by electrical tomography（ ET）. Through measuring the change of voltages on the boundary of the CNT film,ET reconstructs the image of internal conductivity change of the CNT film caused by damages. In order to improve the image quality,L1-normed leastsquares programs（ LSPs） is adopted to perform the reconstruction of the conductivity change. Meanwhile,L-curve criterion is used to determine an appropriate parameter and the inverse reconstruction problem is solved by using the interior-point method. An ET testing system is established and experimental studies are performed,the results have demonstrated the applicability and effectiveness of the proposed methodology.