基于fsFBG传感器的SRM粘接界面服役状态监测

Service status monitoring of SRM bonding interface based on fsFBG sensor

为了更好地模拟SRM(固体火箭发动机)推进剂/衬层粘接界面服役状态下的应力应变状态,设计了不同倾斜角度的界面拉伸试件。将聚合物封装的飞秒激光逐点直写光纤光栅(fsFBG)传感器埋入推进剂/衬层粘接界面试件中,研究了复杂应力载荷作用下fsFBG传感器的响应。结果表明:粘接试件的强度满足发动机设计验收指标,埋入的聚合物封装fsFBG传感器中心波长随拉应力载荷增大而减小,中心波长漂移量与施加的应力载荷具有良好的线性关系,复杂应力情况下传感器响应符合结构实际的服役状态。

In order to better simulate the stress and strain state of the SRM(solid rocket motor)propellant/liner bonding interface in service,the interface tensile specimens with different inclination angles were designed.The polymer-encapsulated femtosecond laser point-by-point direct writing fiber grating(fsFBG)sensor was embedded in the propellant/liner bonding interface test piece,and the response of the fsFBG sensor under complex stress loads was studied.The results show that the strength of the bonded specimen meets the engine design acceptance index,the center wavelength of the embedded polymer-encapsulated fsFBG sensor decreases as the tensile stress load increases,and the center wavelength shift has a good linear relationship with the applied stress load.And the response of the sensor under complex stress conditions is in line with the actual service state of the structure.