应用于注水井的靶式光纤布喇格光栅流量传感器

Target fiber Bragg grating flow sensor for water injection well

为了解决注水井下安装和维护传感器难度大和成本高的问题,设计和理论分析了一种基于杠杆-铰链结构的靶式光纤布喇格光栅(FBG)流量传感器,将传感器结构中的FBG1和FBG3分别粘贴在杠杆-铰链两端构成差动结构,使传感器具有低启动与大量程特性;通过温度补偿光栅FBG2实现了温度和流量的同时测量。对传感器的结构进行了仿真与优化,得出传感器的优化参数,并以此参数为基础进行流量测量、重复性、温度测量、温度补偿、稳定性等实验。实验结果表明,该传感器可以同时测量流体流量和温度,其温度灵敏度为17.94 pm/℃,流量分辨率为0.039 L/s。

In order to solve the problems of difficulty and high cost in installing and maintaining sensors in water injection well,a target type fiber Bragg grating(FBG)flow sensor based on lever-hinge structure is designed and theoretically analyzed.FBG1 and FBG3 in the sensor structure are pasted on the two ends of lever-hinge respectively to form a differential structure,which makes the sensor have the characteristics of low start-up and large range.Temperature compensation grating FBG2 is used to measure the temperature and flow simultaneously.The structure of the sensor is simulated and optimized,and the optimization parameters of the sensor are obtained.Based on these parameters,flow measurement,repeatability,temperature measurement,temperature compensation and stability experiment are carried out.The experimental results show that the sensor can simultaneously measure the fluid flow and temperature,its temperature sensitivity is 17.94 pm/℃and the flow resolution is 0.039 L/s.