针对光纤光栅(FBG)的静水压力增敏及压力温度交叉敏感问题, 提出光纤光栅的椭圆型边孔封装结构。采用有限元方法分析了封装结构中光纤光栅的力学效应, 在此基础上得到优化的椭圆封装结构, 并通过实验检验了理论分析结果。研究结果表明: 优化的椭圆边孔封装结构中光纤光栅的静水压力灵敏度比裸光纤光栅高了4198倍, 而温度灵敏度仅增加了3.4倍, 与裸光纤光栅相比, 压力温度交叉敏感降低了1760倍。该研究结果对光纤光栅压力传感器的实用化研究有参考价值。

An elliptical side-hole encapsulation structure of fiber Bragg grating was proposed to solve the problems of sensitivity enhancement of hydrostatic pressure and the pressure and temperature sensitivities. Finite element method was used to analyze the mechanical effect of the fiber Bragg grating in side-hole encapsulation, and an optimized elliptical structure was derived based on the theoretical analysis, and the conclusions were verified by experiments. Experimental results show that, for the fiber Bragg grating in the optimized elliptical side-hole encapsulation, its hydrostatic pressure sensitivity and temperature sensitivity are increased by 4198 times and 3.4 times compared with bare fiber grating respectively, which means the pressure and temperature crossing sensitivity is decreased by 1760 times.