掺氢航空发动机燃料的基础燃烧特性  

Fundamental Combustion Characteristics of Jet Fuels Mixed with Hydrogen

作　　者：任祝寅[1] 龚雪 暴秀超 REN Zhuyin;GONG Xue;BAO Xiuchao(Institute for Aero Engine,Tsinghua University,Beijing 100084 China;School of Automobile and Transportation,Xihua University,Chengdu 610039 China)

机构地区：[1]清华大学航空发动机研究院,北京100084 [2]西华大学汽车与交通学院,四川成都610039

出　　处：《西华大学学报（自然科学版）》2024年第5期1-7,共7页Journal of Xihua University:Natural Science Edition

基　　金：国家自然科学基金项目(52406155)。

摘　　要：面向航空“碳中和”需求,基于数值模拟研究了掺氢对航空燃油替代燃料火焰传播、自着火以及自着火协助下火焰传播的影响。结果表明:在富燃条件下,无量纲化火焰速度随掺氢量的增加呈非线性增大,可接近20,这给避免火焰回火带来了巨大挑战;掺氢后火焰温度的升高对火焰速度的影响在贫燃时可忽略,而在富燃时不可忽略;对于自着火,纯正十二烷和纯氢两种燃料的混合物存在动力学耦合。基于此构建的自着火风险图表明,氢气在亚音速巡航条件下抑制自着火,而在超音速巡航条件下可能抑制也可能促进自着火,取决于掺氢量和燃烧室入口温度。针对自着火与火焰传播的耦合,一维自着火协助火焰的计算结果表明,对于具有两阶段着火特性的燃料,掺氢的质量分数达到50%时可消除其第一阶段自着火的协助效应。In response to the demand for aviation carbon neutrality,the effects of hydrogen addition on flame propagation,autoignition,and autoignition-assisted flame propagation for surrogate jet fuel were numerically investigated at engine conditions.Results show that for fuel-rich conditions,the normalized flame speed increases nonlinearly with increasing hydrogen ratio and can reach over 20,which poses great challenges for avoiding flashback.For fuel-lean mixtures,the flame speed enhancement due to the flame temperature can be ignored,while cannot be for fuel-rich mixtures.For autoignition,there exists kinetic coupling for n-dodecane/hydrogen mixtures.Based on this,the diagram for autoignition risks is constructed,which indicates that hydrogen suppresses autoignition under subsonic cruising conditions,while it may sup-press or promote autoignition under supersonic cruising conditions,depending on the hydrogen mixing ratio and the combustor inlet temperature.For the coupling of flame propagation and autoignition,the onedimensional calculations of autoignition-assisted flames demonstrate that,for the complex fuel with twostage ignition,the first-stage ignition assistance can be eliminated when the mass fraction of hydrogen reaches 50%.

关 键 词：掺氢 火焰传播 自着火 自着火协助 两阶段着火 

分 类 号：TK16[动力工程及工程热物理—热能工程] V31[航空宇航科学与技术—航空宇航推进理论与工程]