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The accident of fuel tank explosion is an important factor affecting aircraft performance and reliability. Therefore, the inerting system of aircraft fuel tank has been developed in the past decades. The purpose is to reduce the oxygen concentration by filling the tank with nitrogen. In order to monitor the oxygen concentration in the tank, we use tunable diode laser absorption spectroscopy (TDLAS) to measure. Based on the commonly used Matlab numerical simulation module Simulink, this paper establishes the simulation model of intelligent oxygen concentration sensor, and carries out the simulation experiment of measuring oxygen concentration. We compare the influence of different temperature and pressure on the measurement results, and prove the necessity of temperature and pressure compensation. The experimental results show that TDLAS can obtain higher accuracy by adopting the second harmonic detection method under noisy conditions，and can adapt to the high temperature and high pressure environment of the fuel tank. In addition, the research results can provide a theoretical basis for the development of TDLAS based aircraft equipment.