基于光纤传感器的SRM界面黏接应力监测

界面黏接应力是SRM(固体火箭发动机)药柱结构完整性重要方面,也是健康监测的重要参数。为实现对黏接应力实时在线监测,设计了一种聚合物封装的FBG(光纤布拉格光栅)传感器,将其埋入HTPB(hydroxyl-terminated polybutadiene)推进剂/衬层界面黏接试件中。通过对试件在受到拉应力作用下FBG传感器反射光谱的模拟和应力响应测试试验研究了FBG传感器对应力响应规律。结果表明:FBG传感器中心波长随着试件的拉应力增大而减小,线性度较好,且传感器具有较高的灵敏度和稳定性。试件黏接性能测试试验中,FBG传感器性能保持完好,黏接试件强度满足技术指标,验证了传感器封装和埋入方式的可行性。 

Bond stress monitoring of SRM interface based on fiber optic sensor

Bond stress is an important aspect of structural integrity of SRM (solid rocket motor) and also the critical parameter in health monitoring. In order to realize the bond stress real-time online monitoring. A polymer packaged FBG (fiber Bragg grating) sensor was designed and embedded into HTPB(hydroxyl-terminated polybutadiene) propellant/liner bond specimen. The response of FBG sensor was studied when the specimen was subjected to tensile stress by simulation of FBG sensor reflection spectra and stress testing. Results showed that the center wavelength of the FBG sensor decreased with the increasing tensile stress of the specimen, and the sensor had a good linearity and stability. The FBG sensor was intact and the strength of the bonded specimen met the technical specifications in specimen bonding performance test, verifying the feasibility of the designed sensor and embedding method.