基于PTFE管封装的FBG的温度传感研究

Study on Temperature Sensing of FBG Encapsulated by PTFE Tube

基于光纤布拉格光栅(FBG)对温度的敏感特性,且自身体积小、抗电磁干扰等优势,作为温度传感元件被应用于测量精度高或测量环境较苛刻的场合。但FBG较为脆弱且温度灵敏度低,因此对其进行保护以及增敏封装才得以实际应用。本文提出选用热膨胀系数较大且耐低温的聚四氟乙烯(PTFE)材料对裸FBG进行管式封装,封装后的温度灵敏度达23.64 pm/℃,是裸FBG的2.5倍。该研究为光纤光栅在低温领域的传感提供了依据。Based on the advantages of Fiber Bragg Grating (FBG), such as its sensitivity to temperature, small size and anti-electromagnetic interference, it is used in situations with high measurement accuracy or harsh measurement environment as a temperature sensing element. However, FBG is fragile and has low-temperature sensitivity, so it can be applied in practice after being protected and sensitized. Therefore, this paper proposes to use Polytetrafluoroethylene (PTFE) material with large thermal expansion coefficient and low-temperature resistance to package bare FBG in tube. After packaging, the temperature sensitivity reaches 23.64 pm/˚C. The sensitivity is 2.5 times that of bare FBG. This study provides a basis for fiber grating sensing in low-temperature field.