The Oxygen Concentration Measurement of an Aircraft Fuel Tank Inerting System

Abstract

There are several oxygen concentration measurement methods applied in aircraft fuel tank inerting systems. In this work, an aircraft fuel tank inerting experiment system was built and oxygen concentration of the fuel tank ullage (fuel tank space above the surface of the fuel which is filled with fuel vapor and air) and the dissolved oxygen in the fuel was detected with the methods of light absorption and optical fluorescence. The experiment was conducted through different operating conditions and results has illustrated that the light absorption method as well as the optical fluorescence method has the same accuracy sensing calibration gases, but the suitable condition of the two methods are different. Results have shown that the method of light absorption is more suitable to test oxygen concentration of gas mixture, and the method of optical fluorescence is more suitable to detect the concentration of dissolved oxygen in liquid substance.