双折射光子晶体光纤环镜传感灵敏度理论建模及实验研究

项目名称： 双折射光子晶体光纤环镜传感灵敏度理论建模及实验研究

项目编号： No.51505231

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 机械、仪表工业

项目作者： 江莺

作者单位： 南京林业大学

项目金额： 20万元

中文摘要： 光纤传感器普遍存在被测物理量和温度交叉敏感的问题，对数据测量的准确性造成很大影响，而双折射光子晶体光纤环镜传感器具有温度不敏感特性，可很大程度改善交叉敏感的问题，但同时其灵敏度也大为减小。本课题拟开展双折射光子晶体光纤环镜传感灵敏度理论模型及实验研究。内容包括：①建立应变与双折射光子晶体光纤双折射率变化的理论模型，探寻双折射应变系数较大的双折射光子晶体光纤结构设计规则；②建立双折射光子晶体光纤环镜应变灵敏度的理论模型，数值模拟各因素对双折射光子晶体光纤环镜应变灵敏度的影响，探寻提高双折射光子晶体光纤环镜应变灵敏度的方法。③实验研究双折射光子晶体光纤长度及传感长度、监测点波长、双折射率和光纤结构对双折射光子晶体光纤环镜应变灵敏度的影响。本项目通过改善双折射光子晶体光纤环镜自身性能提高灵敏度，无需增加系统复杂性即可解决被测物理量和温度交叉敏感的问题，为大型结构健康监测提供准确、可靠的数据。

中文关键词： 光子晶体光纤环镜；传感灵敏度；监测点波长；双折射率；光纤结构

英文摘要： The sensitivity of fiber sensor to temperature and the measured variable directly affects the accuracy of the datum. Polarization-maintaining photonic crystal fiber loop mirror(PM-PCF FLM) is insensitive to temperature. But its sensing sensitivity is also low. So the project plans to study on the theoretical sensing sensitivity modeling and example of PM-PCF FLM. The detailed works are as following:.①We will deduce the theoretical modeling between the strain and the birefringence change of polarization-maintaining photonic crystal fiber(PM-PCF) and explore the structure design rules of PM-PCF with high strain dependent birefringence coefficient. .②We will deduce the theoretical strain sensitivity modeling of PM-PCF FLM. Then we will study the influences of the each factor in the modeling on the strain sensitivity by numerical simulation and seek the methods of improving the strain sensitivity of PM-PCF FLM..③We will experimentally investigate the influences of PM-PCF length and sensing length, the monitoring point wavelength, birefringence and the PM-PCF structure on the strain sensitivity. .Improving the sensitivity by changing the performance of PM-PCF FLM in the project will not increase the complexity and can realize temperature and the measured variable discrimination. PM-PCF FLM can provide the accurate datum for structural health monitoring.

英文关键词： polarization-maintaining photonic crystal fiber loop mirror;sensing sensitivity;monitoring point wavelength;birefringence;fiber structure