一种基于应力敏感的光纤布拉格光栅流量计

A fiber Bragg grating flow meter based on stress change

利用光纤布拉格光栅(fiber Bragg grating,FBG)对应力敏感,设计了一种流量传感装置。置于流体中的靶片感受到流体的冲击力,使FBG发生轴向应变,从而引起FBG反射谱发生变化,可用于一定范围内对液体流量的实时测量。理论分析和实验结果显示Bragg波长改变量与流量呈现良好的平方关系,进行二项式拟合,其相关系数为0.996。该FBG流量计结构简单,操作方便,在最大流量处的灵敏系数为5.31 L·min^(-1)/nm,精度系数为0.11 L·min^(-1),测量范围为0~4.5 L·min^(-1)。

A flow sensing device is designed using fiber Bragg grating （FBG） stress sensitivity. The impact sensed by the target placed in the fluid under different flow rate leads to FBG axial strain and result in changes of FBG＇ s re- flection spectrum. It could be used on real-time measurement of liquid flow in certain range. Theoretical analysis and experimental results explained a good square relation of Bragg wavelength shift and the flow rate. The correlation coeffi- cient is 0. 996 according to binomial fitting. The flow meter has simple structure and convenient operation. At maxi- mum alow, the sensitivity is 5.31 L ·min^-1/nm, the precision is 0. 11 L·min^-1 and the measurement range is 0 4.5 L·min^-1.