Measurement of Temperature Distribution Based on Optical Fiber-Sensing Technology and Tunable Diode Laser Absorption Spectroscopy

Abstract

Temperature is an important physical quantity in most industrial processes. Distributed temperature sensor (DTS), fiber Bragg grating (FBG), and tunable diode laser absorption spectroscopy (TDLAS) are three primary techniques for temperature measurement using fiber optic sensing and spectrum technology. The DTS system can monitor space temper- ature field along the fiber in real time. In addition, it also can locate a fire source using two sections of optical fibers which are placed orthogonally to each other. The FBG tempera- ture sensor is used to measure the point temperature. The temperature sensitivity of the bare FBG is 10.68 pm/?C and the linearity is 0.99954 in the range of 30–100?C. Based on tunable diode laser absorption spectroscopy (TDLAS), two-dimensional (2D) distribu- tion reconstructions of gas temperature are realized using an algebraic reconstruction technique (ART). The results are in agreement with the simulation results, and the time resolution is less than 1 s.