面向航空发动机苛刻环境光纤传感的关键科学问题研究

As a support technology in monitoring the performance ,life and reliability of high level equipment such as aero-engine and gas press, sensing in harsh environment play an important role in national major project and strategic easy to construct network and compatible with composite material, exhibit great potential application in aero-engine field. When used in harsh environment of ultrahigh temperature and high pressure in aero-engine, optical fiber sensor have some problem, its temperature tolerance becomes lower, the mechanical strength decline, leakage mode loss appears when single crystal fiber works in multi-mode transmission. In this project application, we innovatively propose that by constructing sapphire fiber with compact polycrystalline cladding and quasi photonic lattice cladding, constructing micro structure pure quartz fiber with double-poly-crystalline coating, the difficult problem above can be fundamentally solved. Also, we will deeply study the thermodynamics problem of single crystal growth in micro region between poly-crystalline cladding and fiber core, study the problem of femtosecond laser space-time focus inscribe quasi-photonic lattice cladding and limited mode volume, study the problem of regulating and controlling stress distribution in poly-crystalline cladding and cladding micro region, study the fabrication of few mode or quasi single mode sapphire fiber grating and high temperature micro-structure fiber grating. Developing the fabrication of high temperature dynamic pressure sensor, high temperature vibration sensor and high speed sensor demodulator, realize temperature, strain and other parameter sensing in harsh environment of aero-engine.

苛刻环境传感作为监测航空发动机/燃机压气机等高端航空装备性能、寿命和可靠性的支撑性技术，在国家重大工程和战略安全上发挥着重要作用。光纤传感具有质量轻、无源、可组网复用、与复合材料性能兼容等优势，在航空发动机领域展现出巨大应用潜能。针对航空发动机超高温、高压等苛刻环境，光纤传感应用存在光纤材料耐温特性差、高温机械强度下降和单晶光纤多模传输及强泄漏模式损耗等问题。本项目创新性提出通过构建致密多晶包层和类光子晶格包层结构化蓝宝石光纤、微结构纯石英光纤双层多晶涂层生长，从根本上解决上述难题；并深入研究多晶包层与纤芯间微区单晶生长材料热力学问题，飞秒激光时空聚焦刻写类光子晶格包层及其限制模式容积问题，多晶涂层间及与包层微区内应力分布调控问题；研究少模或准单模蓝宝石光纤光栅和耐高温微结构光纤栅的飞秒激光制备，高温动态压力与振动传感及高速解调技术，实现航空发动机苛刻环境的温度、应变以及多参数传感。

项目针对航空发动机故障诊断技术及感知器件制备的关键科学问题，进行了面向航空发动机苛刻环境光纤传感技术研究，主要研究了蓝宝石光纤涂层制备、蓝宝石光纤光栅高温传感器制备、高温脉动压力和振动传感器设计；利用LPCVD法制备了BN和SiBCN双包层、利用原子层沉积法制备氧化铝包层，解决了蓝宝石光纤材料高温机械强度下降、单晶光纤多模传输及强泄漏模式损耗等问题；采用管棒法制备了长期耐温超过1000℃的蓝宝石晶体衍生光纤；采用飞秒激光螺旋直写、逐点直写等技术制备了耐温超过1600℃的蓝宝石光纤光栅高温传感器，以及耐温超过1000℃少模晶体衍生光纤光栅高温传感器；利用电弧放电技术，实现了蓝宝石光纤与石英光纤高效耦合，解决了光纤传感信号长距离传输不稳定问题；构建了高温测试和压力测量的标定系统，设计制备了基于蓝宝石光纤结构的高温及压力传感器，分析了高温及压力的传感特性，为航空发动机故障诊断与结构参数监测提供了可靠的传感技术与器件。项目共发表学术论文12篇，其中SCI论文10篇（影响因子>2，7篇）、EI论文2篇，申请国家发明专利6项（授权2项）。