金属封装式FBG传感器设计及应变传递试验  

Design of Metallic Packaged Fiber Bragg Grating Sensor and Its Strain Transfer Experiment

作　　者：杜翠翠 孔德仁[1] 徐春冬 DU Cuicui;KONG Deren;XU Chundong(School of Mechanical Engineering,Nanjing University of Science&Technology,Nanjing 210014,China)

机构地区：[1]南京理工大学机械工程学院,江苏南京210014

出　　处：《湖南大学学报（自然科学版）》2023年第4期9-20,共12页Journal of Hunan University:Natural Sciences

基　　金：国家自然科学基金资助项目(11372143);国防科工局技术基础科研项目(995-14021006010401);江苏省自然科学基金资助项目(BK20190464)。

摘　　要：为实现对被测基体结构应变的精确测量,设计一种基于金属封装粘贴式光纤光栅应变传感器,建立了6层结构的应变传递模型,分析推导了被测基体层、基底粘胶层、封装基底层、光纤粘胶层、保护层及光纤光栅层的应变传递机理,并通过理论分析和有限元仿真对比分析了光纤光栅长度、光纤粘胶层厚度、基底粘胶层厚度、中间层的弹性模量和泊松比等主要因素对平均应变传递率的影响.根据仿真结果,确定所设计的金属封装粘贴式光纤光栅传感器的封装材质、尺寸及粘胶层厚度.最后通过设计等强度悬臂梁作为施加载荷载体,提出应变传递误差修正系数,对上述铝合金封装粘贴式光纤光栅及裸光纤光栅传感器进行了应变传递对比试验.结果表明,裸光纤光栅和金属封装式光纤光栅传感器的平均应变传递率分别为98.25%和98.15%,与仿真计算误差在0.15%~0.25%以内.To achieve an accurate measure of the strain value of the measured structures,a metallic packaged fiber Bragg grating(FBG)strain sensor is designed.A six-layer strain transfer model of the FBG sensor is established,and its strain transfer mechanism from the measured substrate layer,substrate adhesive layer,packaging substrate layer,adhesive layer of FBG,protective layer,and FBG layer is analyzed and derived.Through theoretical analysis and finite element simulation,the effects of the FBG length,the thickness of the FBG layer and substrate bonded layer,the elastic modulus,and Poisson's ratio of middle layers on the average strain transfer rate are comparatively analyzed.According to the simulation results,the packaging material,size,and adhesive layer thickness of the designed FBG sensor are determined.Finally,an equal-intensity cantilever beam that provides the load on FBG is designed,and a correction coefficient of the strain transfer error is proposed.A comparison test of strain transfer is carried out on the bare FBG and metallic packaged FBG sensors.The results show that their average strain transfer rates are 98.25%and 98.15%,respectively,and the error between the simulation results is within 0.15%~0.25%.

关 键 词：金属封装式光纤光栅传感器 平均应变传递率 有限元仿真 等强度悬臂梁 

分 类 号：TP212.9.1[自动化与计算机技术—检测技术与自动化装置] TH825[自动化与计算机技术—控制科学与工程]