耐高温光纤振动、应力集成传感器的基础理论和关键技术研究

Vibration and stress are two important parameters reflecting the working status of the aircraft engine. As to the limitation of traditional electric sensor such as low corrosion resistance, susceptible to electromagnetic interference and so on, it is needed to further explore the vibration, stress sensing and measurement methods applicable to high temperature environment. Because of their advantages of high sensitivity, anti-electromagnetic interference and good corrosion resistance, fiber optic sensors can be used in harsh conditions such as severe shaking, high temperature and high pressure. This project focuses on the development of the sapphire fiber sensor suitable for vibration and stress measurement in high temperature harsh conditions based on femtosecond laser processing technology. The main research contents are as follows: Analysis of intrinsic structures, structure design and optimization of the high temperature optic fiber vibration and stress sensor; The material removal mechanism of sapphire fiber and the fabrication processes using femtosecond laser processing technology; Signal demodulation and the method of eliminating cross-sensitivity interference; Durable mechanism, damage mechanism and protective method of the sensor under the complex environment of high temperature; the performance test of the sensor and its application in the micro engine. The developed sensor has an important value of engineering application because it can satisfy the special requirements of vibration, stress measurement for the aircraft engine under harsh working conditions, provide valid state parameters for the study on damage mechanism of the hot runner, provide important basis for the development, performance evaluation, and health monitoring of aircraft engine.

振动及应力是反映航空发动机工作状态的重要参数，但传统电类传感器的耐腐性差、易受电磁干扰、局限性较大，因此需进一步探索适用于高温环境下的振动、应力感知和测量手段。光纤传感器由于其所具有的灵敏度高、抗电磁干扰、耐腐蚀性好等优点，可用于剧烈振动和高温高压等恶劣环境。本项目拟基于飞秒激光加工技术制作适用于高温复杂环境下振动、应力测量的蓝宝石光纤集成传感器并开展其基础理论和关键技术研究。主要工作包括：传感器的本征特性理论分析，飞秒激光加工过程中蓝宝石光纤的材料去除机理及制备工艺，信号解调及交叉敏感干扰的消除方法，传感器在高温复杂环境下的耐受机理、损伤机制及其防护方法，传感器的应用研究等。所研制的传感器能够满足航空发动机严苛工作状态下对振动、应力测量的特殊要求，为高温流道件损伤机理研究提供有效状态参数，为航空发动机的研制、性能评价以及健康状态监测等提供重要依据，具有重要的理论研究意义和工程应用价值。

针对航空发动机等动力系统高温流道件高温恶劣工况条件下振动、应力测量的需求，项目以蓝宝石光纤为研究对象，以飞秒激光加工技术为手段，研制光纤耐高温振动、应力传感器并开展了相关的基础问题和关键技术研究。主要完成的工作包括：1、提出了基于蓝宝石光纤和普通光纤相结合的振动、应力集成传感器，获得了光纤传感器在高温、振动、交变应力复合作用下的力学模型、动态光波导特性模型和传热数理模型，设计了传感器的结构，并优化了其参数。2、开展了传感器制备工艺研究，获得了飞秒激光加工制作FBG的加工工艺流程；设计并研制了传感器的高精度信号解调系统，实现了集成传感器耦合信号的分离，抑制了不同参量间的交叉干扰。3、研制得到耐高温温度、振动、应力传感器的原型样机，最高测量温度达到1900K，稳定工作时间10小时以上；温度传感器在中航工业北京长城计量测试技术研究所开展了校准测试，结果表明：传感器可在燃气流速马赫数0.6、1873K的工况下工作正常，测量精度为±0.36%。集成传感器振动测量频响范围达到0-8kHz，量程100g；应力测量范围为0-500Mpa；振动和应力传感器分别在陕西省计量科学研究院进行校准，结果表明：在测量范围内，振动传感器的线性度为1%。、应力传感器的线性度为0.77%。4、开展了传感器的应用研究，针对航空发动机具体安装环境，设计了保护封装，封装后的传感器在多个发动机地面试验台上进行了测试，验证了传感器的工作可靠性。.获科技奖励3项；共发表高水平论文28篇，其中SCI收录（源刊）22篇；申请国家发明专利11项，已授权9项（1项已转让）；获软件著作权3项；培养研究生4名，培养学生获各类科技竞赛奖励3项。