Design And Simulation Of Fuel Tank Inerting System For Aircrafts

The inerting technology of aircrafts refers to inject nitrogen-enriched air(NEA) generated by on-board air separation module(ASM) into fuel tank to maintain the oxygen concentration being lower than the fuel flammable limit. Today, it becomes one of the most effective and economical ways to ensure safety and inhibit explosion accident of aircraft fuel tank.Combining with the task of XX aircraft fuel tank inerting system, the design and simulation of the intering system is studied in detail including:1)The previous research results and contributions were systematically summarized and reviewed. Consequently, a research scheme was proposed.2)Based on structure design, analysis of security and demands of performance, a design principle was proposed, the overall layout of the inerting system was conducted, the major components ware selected and some reasonable suggestions for this inerting system were offered.3) In term of the essential physical-chemical characteristics of aviation fuel and the conservation of mass, a theoretical mathematical model was established and solved via Matlab programming to acquire the demand of flow rate of NEA. The model was verified by comparing the prediction result with the experimental data reported in literatures. According to structure characteristics of XX aircraft fuel tank, the flow rate of NEA and the influence factors were analyzed. The variation curve of flow rate related to the time was depicted to summarizea method to optimize the flow rate of NEA.4)The variation of oxygen concentration on ullage of XX aircraft fuel tank was predicted via CFD method.The study results reveal that the change of the NEA inlet ports or vent port definitely affect the oxygen concentration on ullage of bays, but it has less impact on the averaged oxygen concentration on ullage of the whole fuel tank, Although a multi-inlets arrangement could uniform the variation of oxygen concentration on ullage of all bays, it brings negative effect on the utilization of NEA;Therefore, the influence caused by tank vent arrangement should be also considered and the distribution method of NEA should be further studied in order to propose an optimal inerting gas distribution method.The study of this paper provides a useful reference for the design and selction of XX aircraft fuel tank inerting system.