高Ka数下分子扩散效应对氨气/氢气/空气预混火焰结构的影响  

Effect of Differential Diffusion on the Structure of High Karlovitz Number Premixed Ammonia/Hydrogen/Air Flames

作　　者：蔡骁 樊庆骦 王金华[1] 黄佐华[1] 李中山 CAI Xiao;FAN Qingshuang;WANG Jinhua;HUANG Zuohua;LI Zhongshan(State Key Laboratory of Multiphase Flow in Power Engineering,Xi'an Jiaotong University,Xi'an 710049,China;Division of Combustion Physics,Lund University,Lund S22100,Sweden)

机构地区：[1]西安交通大学动力工程多相流国家重点实验室,西安710049 [2]隆德大学燃烧物理系,瑞典隆德S22100

出　　处：《工程热物理学报》2022年第8期2025-2032,共8页Journal of Engineering Thermophysics

基　　金：国家自然科学基金(No.52076171,No.91841302);博士后基金(No.2021M692536)。

摘　　要：本文采用平面激光诱导荧光和瑞利散射测温技术同步测量了氨气/氢气/空气预混射流火焰关键组分场和温度场,研究了分子扩散效应对预混火焰结构的影响。发展了NH-PLIF激光诊断技术,能准确表征氨气燃烧的反应区。对层流燃烧特性相近但Le数差异明显的三种火焰进行研究,发现在高Ka数下,三种火焰的反应区均发生局部增厚。并且三种火焰的反应区厚度随着Le数的增加而增加,表明即使在增厚反应区内,分子扩散效应仍然影响湍流燃烧。Simultaneous planar laser induced fluorescence(PLIF) and Rayleigh scattering thermometry(RST) were applied to measure the key species and temperature fields of premixed ammonia/hydrogen/air jet flames to investigate the effects of differential diffusion on flame structure.NH-PLIF technique was developed to properly characterize the reaction zone of ammonia flames.Three flames with similar laminar combustion characteristics but different Lewis numbers(Le) were investigated. Results show that the reaction zone are locally thickened for all flames at high Karlovitz number(Ka). Furthermore, the reaction layer thickness increases with the Le, indicating that the differential diffusion still plays a role in the turbulent combustion even in the distributed reaction zone regime.

关 键 词：分子扩散效应 湍流火焰结构 反应区增厚 高Ka数 

分 类 号：TK16[动力工程及工程热物理—热能工程]