摘要
采用微分计算方法,在考虑、不考虑燃油中溶解氧逸出这2种极限情况下,建立了燃油箱气相空间冲洗惰化的数学模型,并用实验数据验证了模型的正确性.以无氧逸出模型为基础,定义了物理意义明确的惰化率、气相体积换气次数和总体积换气次数3个参数,用于简捷描述惰化效果及所需要的冲洗气量.研究结果显示:在无氧逸出模型中,气相体积换气次数及惰化终了时气相空间的含氧量与载油量无关,而总体积换气次数随载油量的增加线性减少;在有氧逸出模型中,由于受从燃油中逸出氧气的影响,气相体积换气次数随载油量增加而急剧上升,而总体积换气次数仍与载油量成反比关系;当载油率相同时,有氧逸出模型的换气次数大于无氧逸出模型的换气次数.在进行实际冲洗惰化设计时,可在这2种模型的计算结果之间选择合适的值来估算富氮气体的流量.
Considering or not the evolution of the dissolved oxygen from fuel oil,two different washing inerting mathematical models of ullage for the fuel tank are established with differential method,and the models are verified by experimental data.On the basis of the model without oxygen evolution,three parameters of inerting ratio,volumetric tank exchange of ullage,and total volumetric tank exchange are defined to simplify the description of the inerting process and the calculation of the nitrogen-enriched air flow rate.The results show that the volumetric tank exchange of ullage and the final oxygen concentration of the inerted ullage are independent of the fuel load,but the total volumetric tank exchange decreases when the fuel load increases in the model without oxygen evolution.In the oxygen evolution model,because some oxygen is released from the fuel,the volumetric tank exchange increases dramatically when the fuel load increases,but the total volumetric tank exchange is still inversely related to the fuel load.Under the same fuel load,both volumetric tank exchange of ullage and total volumetric tank exchange in the oxygen evolution model are higher than those in the model without oxygen evolution.In the washing inerting design,aproper flow rate of nitrogen-enriched air can be estimated and determined according to the calculating results via the two models.
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
2010年第9期16-20,114,共6页
Journal of Xi'an Jiaotong University
基金
航空科学基金资助项目(50306017)
关键词
燃油惰化
冲洗
换气次数
燃油箱
气体逸出
fuel inerting
washing
volumetric tank exchange
fuel tank
gas evolution
