基于平衡氧浓度的飞机燃油箱可燃性降低仿真研究  

Simulation study on reduction of aircraft fuel tank flammability based on equilibrium oxygen concentration

作　　者：杨建忠 崔勇 杨士斌 YANG Jian-zhong;CUI Yong;YANG Shi-bin(College of Safety Science and Engineering,Civil Aviation University of China,Tianjin 300300,China)

机构地区：[1]中国民航大学安全科学与工程学院,天津300300

出　　处：《消防科学与技术》2022年第5期645-650,共6页Fire Science and Technology

摘　　要：氧气从燃油中逸出,使燃油箱空余空间中氧气浓度上升,增加了燃油蒸气点燃爆炸的风险,使得飞机燃油箱处于不安全的状态,可使用降低可燃性的方法使燃油箱惰化。使用富氮气体(NEA)使飞机燃油箱空余空间氧体积分数降至14.5%以下,确保燃油箱中的氧气浓度不足以支持燃烧,使燃油箱处于惰化状态。采用NEA惰化的方式,建立油箱空余空间氧浓度模型,考虑氧气从燃油中析出,建立随高度变化的燃油箱可燃性降低(FRM)模型。仿真结果表明,燃油箱的可靠可燃性随着FRM模型的最小故障间隔时间(MTBF)的增加而减小,得出满足可靠可燃性的最小MTBF;确定MTBF,通过仿真,得出FRM模型满足性能可燃性所需的最小流量:下降阶段满足要求所需的最小高流量和其他飞行阶段满足要求所需的最小低流量。Oxygen evolves from the fuel, increasing the oxygen concentration in the ullage of the fuel tank, which increases the risk of fuel vapor igniting explosion, making the aircraft fuel tank in an unsafe state. The fuel tank can be inerted by flammability reducing method. Nitrogen-riched-gas is used to reduce the oxygen concentration in the ullage of the tank below the level of 14.5%, to ensure the safety of the fuel tank. By establishing the tank ullage oxygen concentration model, considering the dissolution of dissolved oxygen in the fuel, the FRM model which the concentration changing with the altitude was established. The simulation showed that the reliability flammability of fuel tank decreases with the increase of the minimum time between failures(MTBF) of the model, and the minimum MTBF satisfying the reliable flammability is obtained. Through simulation, the minimum flow required by the model to meet the performance flammability was obtained: the minimum high flow required to satisfy the requirements in descent and the minimum low flow required to meet the requirements in other phrases.

关 键 词：可燃性 惰化 富氮气体 平衡氧浓度 可靠性 

分 类 号：X913.4[环境科学与工程—安全科学] V228[航空宇航科学与技术—飞行器设计]