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The fuel tank safety is an important guarantee of the entire aircraft safety, however, aviation kerosene (fuel), oxygen, and various forms of aircraft fuel tank ignition source, aviation kerosene, liquid steam may be in support of oxygen, ignition source burning or explosion occurred. First, the combustion triangle fuel, oxidizer and an ignition source of these three basic elements, in particular to aviation kerosene has a flash point, vapor pressure and the combustion limit, oxygen concentration distribution in the aircraft flight envelope, and the fuel tank may the presence of an ignition source, a comprehensive analysis of the fire hazard exists in the fuel tank; Secondly, the use of different equivalence ratios of hydrogen and oxygen premixed gas in the closed space of the combustion process, the CFD method closed space in the analog pre Applicability of mixed gas burner which, through the front of the calculation results are compared CFD method k-ε turbulence model and the finite rate combustion model can simulate a combustible gas mixture combustion process temperature, pressure, etc. parameters. Then, using CFD method for aircraft fuel tank aviation kerosene vapor and oxygen premixed gas combustion process under high temperature ignition source numerical simulation and equivalence ratio change aviation kerosene vapor space, an airplane flight the pressure of the environment, as well as conditions such as the concentration of nitrogen in the aviation kerosene and air mixture, summarized the variation of the combustion process under different conditions of temperature, pressure and other parameters; aviation kerosene vapor and oxygen premixed gas combustion to the safety of the fuel tank exists great threat, one of the ways to prevent burning is passed into the fuel tank inerting nitrogen rich, so that the concentration of oxygen in the space is below the limiting oxygen concentration. Inerting process numerical simulation, and the simulation results were compared with ideal mixing model and the empirical formula of the previous; designed a series of examples, such as the rich body of nitrogen attributes parameters (NEA gas flow and the purity), the attribute parameters of the fuel tank (the shape and volume of the fuel tank), and a nozzle attribute parameter placement position and the nozzle (nozzle diameter), to find the changes in these parameters on the fuel tank inerting process, obtained affect the main fuel tank inerting process several parameters. Finally, the parameters affecting the inerting process mainly nitrogen-rich gas flow, purity and nozzle diameter, ideal mixing model does not contain changes in the diameter of the nozzle of the inerting process, this article nozzle diameter of the inerting process quantitative analysis, and the idea of ??two-zone model based on the distribution of the oxygen concentration in the fuel tank under different Reynolds number, and the combined CFD calculations to establish the two-region model suitable for different Reynolds numbers, perfected the ideal hybrid model .
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