温度影响光纤光栅传感器性能蜕化机理及实验研究

结构健康监测中，光纤布拉格光栅(FBG)传感器性能蜕化将会严重影响整个监测系统的稳定性和准确性。而高温、高压等恶劣条件，均可能导致FBG传感器性能蜕化。基于光纤光栅传感器温度传感原理，分析了温度引起光纤光栅传感器性能蜕化的机理，并通过软件仿真和相应温度循环实验，分别考察了温度对不同FBG传感器性能蜕化的影响。实验结果表明，温度对FBG传感器性能蜕化的影响与FBG传感器自身质量参数有关。对于普通FBG传感器，随着温度循环次数增加，反射光谱峰值逐渐降低；而对于刻写完成后，光纤中仍含有少量氢分子的FBG传感器，随着温度循环次数增加，反射光谱不仅峰值逐渐降低，而且中心波长逐渐发生蓝移。

Mechanism and Experimental Research on Performance Degeneratio of Fiber Bragg Grating Affected by Temperature

In structural health monitoring, performance degeneration of optical fiber Bragg grating (FBG) sensor will seriously affect the whole monitoring system′s stability and accuracy. High temperature, high pressure and many other bad conditions may cause FBG sensor performance degeneration. Therefore, in this paper, the theory that fiber Bragg grating sensor performance degeneration caused by temperature is analyzed. Influences of different kinds of FBG sensor on performance degeneration are analyzed quantitatively by numerical simulation and temperature cycling experiment. The experimental results show that performance degeneration of FBG is related to its own reasons. For normal FBG sensors, its peak value of reflective spectrum decreases with the increasing of the cycle numbers. For FBG sensors containning some hydrogen molecules, with the numbers of cycle increasing, its peak value of reflective spectrum decreases, and its central wavelength shifts towards short wavelength.