Fibre Bragg Gratings in Embedded Microstructured Optical Fibres Allow Distinguishing between Symmetric and Anti-Symmetric Lamb Waves in Carbon Fibre Reinforced Composites

Sensors

Thomas Geernaert¹  Sidney Goossens¹  Francis Berghmans¹  Ben De Pauw¹  Hugo Thienpont¹  Dimitrios Habas² 

[1] Department of Applied Physics and Photonics (TONA), Vrije Universiteit Brussel, Brussels Photonics (B-PHOT), Pleinlaan 2, 1050 Brussels, Belgium;Hellenic Aerospace Industry, Engineering Research Design and Development Directorate, 32009 Shimatari, Greece;

关键词: fibre Bragg gratings;    Lamb waves;    CFRP;    impact damages;   

DOI  :  10.3390/s17091948

来源: DOAJ

【 摘 要 】

Conventional contact sensors used for Lamb wave-based ultrasonic inspection, such as piezo-electric transducers, measure omnidirectional strain and do not allow distinguishing between fundamental symmetric and anti-symmetric modes. In this paper, we show that the use of a single fibre Bragg grating created in a dedicated microstructured optical fibre allows one to directly make the distinction between these fundamental Lamb wave modes. This feature stems from the different sensitivities of the microstructured fibre to axial and transverse strain. We fabricated carbon fibre-reinforced polymer panels equipped with embedded microstructured optical fibre sensors and experimentally demonstrated the strain waves associated with the propagating Lamb waves in both the axial and transverse directions of the optical fibre.

【 授权许可】

Unknown