智能全分布式光纤应变传感精度的理论分析与实验研究

Theoretical Analysis and Experimental Study on Distributed Fiber Optical Strain Sensing Precision

摘要:

分布式光纤传感器可构成智能结构的神经系统。首次从力学的角度对分布式光纤应变传感的精度进行了系统的理论分析和实验研究，基于考虑光纤-基材之间的力学耦合作用，系统建立了两者耦合效应即应变传递的分析方法和分析模型，得到了应变传递关系的理论解答，以及应变检测精度的范围，分析了涂层对光纤应变感知能力的影响，根据分析结果研制了具有工程实用化意义的传感光纤。对普通二次涂敷光纤通讯光纤及研制的样本，分别进行了分布式应变检测实验，发现应变检测精度的理论分析结果存在偏高倾向，但与实测数据相差不超过4%，表明所建立的理论分析方法基本可靠，从而为分布式光纤应变传感的优化设计及性能分析提供了理论参照。

Abstract:

The systematic theoretical analysis and experimental study on distributed fiber optical strain sensing precision are performed from perspective of mechanics for the first time. Based on considering the mechanical coupling action between optical fiber and matrix, the analytical approach and model for analyzing the coupling effect namely strain transfer relationship is established systematically, the theoretical formulation and strain measurement precision range are obtained. The effects of fiber optical coating parameters on optical fiber’s ability to perceive strain are analyzed, and according to analytical results the sensing optical fiber sensing sample applicable to practical engineering is developed. The experiments with distributed strain measurement for ordinary communication optical fiber and developed sample are conducted respectively. It is found the outcomes of theoretical analysis of strain measurement precision tend to be higher, but not exceed measured data by 2%, which shows the proposed analytical approach is basically applicable.