Research on spectrum characteristics of fiber Bragg grating under acoustic emission waves

A fiber Bragg grating (FBG) acoustic emission (AE) sensing model is established and the cosine-Gauss function is used to simulate the dynamic strain field along the FBG generated by AE waves. The theoretical simulations show that there is a regular relation between the characteristics of FBG reflection spectrum and the parameters of AE wave. In order to verify the simulation results, a FBG AE sensing system is constructed with a narrow bandwidth laser and a novel FBG AE sensor is designed in this system. The data obtained from experiments fairly coincide with the simulation results. Therefore, a useful tool for damage identification and localization using AE waveform analysis is provided in this paper.