光纤Bragg光栅可变灵敏度液位传感器设计

Design of variable sensitivity liquid level sensor for FBG

为了实现对液位的多灵敏度状态下监测,设计了一种利用光纤Bragg光栅(FBG)的可变灵敏度液位传感探头。将薄膜片上的液体压力通过传压杆传送给悬臂梁,将FBG粘贴于悬臂梁上表面,利用灵敏度变换阀改变悬臂梁长度而改变传感器的灵敏度。对悬臂梁进行有限元仿真优化计算,得到悬臂梁的变形特性。悬臂梁长度分别调节为100,90,80 mm状态下,最大变形出现在悬臂梁尖端,分别为4.266,3.457,2.736 mm,裸光栅粘贴处,对应的灵敏度分别为2.0,1.5,1.0 mm/m,实现灵敏度变换。

In order to achieve level of variable sensitivity monitoring is designed using a fiber Bragg grating （FBG） with variable sensitivity level probe. Liquid pressure on film is transmitted to cantilever beam through pressure bar, FBG is pasted on upper surface of cantilever beam,using sensitivity shift valve to change cantilever length, so as to change sensitivity of sensor. Calculated deformation properties of the cantilever beam by finite element simulation and optimization. The length of cantilever beam are adjusted to 100 mm, 90 mm, 80 mm. In all the above-mentioned states, the maximum deformation occurs in the tip of cantilever beam, which are 4. 266, 3. 457,2. 736 mm respectively. Corresponding where bare grating pasted, the sensitivitues are 2.0,1.5,1.0 mm/ m, to achieve sensitivity transformation.