不规则燃油箱惰化系统进出口优化方法

Optimization method for inlet and outlet of irregular fuel tank inerting system

为解决不规则燃油箱惰化时,出现的氧体积分数分布不均匀、惰化区域不充分的难题,以熵权改进优劣解距离(TOPSIS)理论为基础,提出一种适用于不规则油箱惰化系统的优化方法,并结合数值仿真方法进行综合评价,实现波音747飞机惰化系统进出口的优化设计。结果表明:根据熵权改进TOPSIS理论设计的惰化方案,不仅可以降低惰性气体流量需求,而且可以使得惰化空间氧体积分数分布更为均匀;优化后的波音747飞机惰化方案,综合性能指标提升22.67%,速度性指标提升2.97%,均匀性指标提升27.78%;单侧偏置惰化方案设计思路,可以增加流通路径、延长惰性气体存续时间,使得油箱惰化时氧气分布更为均匀、氧体积分数下降迅速。

An optimization method appropriate for the irregular fuel tank inerting system is proposed based on the Entropy-weight improvement TOPSIS method in order to address the issues of uneven oxygen distribution and insufficient inerting when the irregular fuel tank is inserted.When combined with the numerical simulation method,the comprehensive evaluation is carried out,and the optimization design for the Boeing 747 inerting system is then realized.The results show that:The inerting scheme designed by the Entropy-weight improvement TOPSIS method can not only reduce the flow demand of inert gas but also make the oxygen distribution more uniform.The optimization inerting scheme of Boeing 747 aircraft has improved the comprehensive performance metrics by 22.67%,the speed metrics by 2.97%,and the uniformity metrics by 27.78%.The design idea of a“one-side bias placement”inerting scheme can increase the flow path and prolong the existence time of inert gas so that the oxygen distribution is more uniform and the oxygen concentration decreases rapidly when the fuel tank is inserted.