应用于航天发动机的镀金光纤光栅高温动应变测量技术  

Application of gold-plated grating in high temperature dynamic strain measurement for aerospace engines

作　　者：常莹 杜永清[1] 陈晖[1] 朱柯钦 马晓松 邓锦荣 CHANG Ying;DU Yongqing;CHEN Hui;ZHU Keqin;MA Xiaosong;DENG Jinrong(Xi'an Aerospace Propulsion Institute,Xi'an 710100,China;Northwestern Polytechnical University,Xi'an 710072,China)

机构地区：[1]西安航天动力研究所,陕西西安710100 [2]西北工业大学,陕西西安710072

出　　处：《火箭推进》2024年第6期127-134,共8页Journal of Rocket Propulsion

基　　金：国家装备预研基金(6140923020303)。

摘　　要：在航天发动机的地面热试车或高空模拟试验中,通过准确测量高温管路的动应变参数,可以有效掌握结构疲劳和裂纹情况,从而提高发动机载荷能力分析和剩余寿命预测能力,这对于掌握发动机的工作状态具有重要的工程意义。西安航天动力研究所针对该动应变测量需求,论证了高温光纤光栅(FBG)应变测量技术的可行性和有效性,提出采用镀金涂层的飞秒激光刻写光纤光栅(FBG)进行高温动应变的测量。通过高温温度特性试验,开展了温度补偿技术研究,明确了高温应变温度补偿方案;在高温等强度梁上对高温应变测量准确度和温度补偿方案的可行性进行了验证。结果表明,经过高温温度补偿以后应变测量误差在±5×10-5范围内,可以满足航天液体发动机高温动应变测量准确度的要求。该光纤高温应变技术目前在本研究所设计的多个型号发动机热试车中高温动应变的测量中获得了良好应用。该技术具有测量成本低、测量准确性高等特点,可以在300~800℃范围内实现管路壁面动应变的准确测量。In the ground hot test or high-altitude simulation test of aerospace engines,it is necessary to accurately measure the dynamic strain parameters of high-temperature pipelines to determine the structural dynamic strength and mechanical properties of key high-temperature pipelines,which is of great significance for studying the performance and safety characteristics of engines.Xi'an Aerospace Propulsion Institute has conducted in-depth research on high-temperature fiber Bragg grating(FBG)strain measurement technology to meet the measurement requirements of high-temperature dynamic strain in engine hot testing and high-altitude simulation tests.It was proposed to use femtosecond laser engraved fiber Bragg gratings coated with gold for high-temperature dynamic strain measurement,breaking through the key technology of temperature compensation within the temperature range of gold-plated FBG(25-800)℃,and forming a process specification for gold-plated FBG high-temperature strain pasting.The accuracy of high-temperature strain measurement has been verified on high-temperature high-strength beams,and the strain measurement error can be controlled within±15μεwithin the scope.The fiber optic high-temperature dynamic strain technology has been well applied to the measurement of high-temperature strain in the hot test of multiple models of engines designed by Xi'an Aerospace Propulsion Institute.It has the characteristics of low measurement cost and high measurement accuracy,and can accurately measure the high-temperature dynamic strain of pipeline wall working temperature within the range of 300~800℃.In the ground hot test or high-altitude simulation test of aerospace engines,it is necessary to accurately measure the dynamic strain parameters of high-temperature pipelines to determine the structural dynamic strength and mechanical properties of key high-temperature pipelines,which is of great significance for studying the performance and safety characteristics of engines.According to the measurement requirements of hi

关 键 词：镀金光纤光栅 航天发动机 热试车 高温动应变 温度补偿 

分 类 号：V416.6[航空宇航科学与技术—航空宇航推进理论与工程]