Abstract: Installing an inerting system is an important way to prevent explosion of aircraft fuel tanks. The change rule of fuel tank oxygen concentration is one of the basic research courses of the design of inerting system. Fuel consumption, as one of the factors affecting the change of oxygen concentration, has a non-negligible effect on the change of the aircraft fuel tank oxygen concentration. This paper intends to propose a calculation model for the oxygen concentration of the gas phase space of the fuel tank considering the fuel consumption parameter, combined with the segmented fuel consumption change relationship in the real flight data of the aircraft, to analyze the impact of fuel consumption and initial fuel load rate and fuel temperature on the oxygen concentration change of the aircraft fuel tank at each flight phase. And the paper compares the impact with the changes in the aircraft fuel tank oxygen concentration without considering fuel consumption. The results of the study show that fuel consumption has a greater influence on the calculated results of equilibrium oxygen concentration during climb, cruise, and descent, and less impact during the taxi- out, take- off, and approach landing phases. During the taxi- out, take- off, and approach landing phases, the initial fuel load rate has little effect on the oxygen concentration, and in the climb, cruise and descent phases, the higher the initial fuel load rate, the higher the equilibrium oxygen concentration value of the aircraft fuel tank. And as the initial fuel load rate decreases, the equilibrium oxygen concentration value at the same altitude is reduced. Different sea-level temperatures have varying degrees of influence on the oxygen concentration in the gas phase space at various phases.

Key words:

fuel tank explosion proof, inerting system, equilibrium oxygen concentration, fuel consumption, flight phase, simulation  ,