A cryogenic sensor based on Fiber Bragg Grating for Storage Monitoring of Liquefied Natural Gas

Condition monitoring is critical for the safe usage of Liquefied Natural Gas (LNG). Temperature distribution is an important index of LNG storage and it can reflect the tendency of heat leakage and the situation of evaporation. However, traditional electric sensor may cause explosion due to spark. In this paper, a cryogenic sensor based on fiber Bragg grating (FBG) is developed, in which the fiber with preload force is adhered with temperature-sensitive metal. The temperature characteristics of the cryogenic sensor between -190°C to -80°C are revealed by the experimental test by using liquefied nitrogen. The results indicate good linearity and the maximum error is less than 0.35°C, which indicates the availability of this sensor in LNG storage.