摘要
应用高速激光诊断系统,对中心分层旋流火焰开展了流场与火焰结构的多参数同步测量,研究了分层比对火焰动力学及瞬态流动结构的影响。通过20kHz高频平面激光诱导荧光和高频粒子示踪测速技术,研究了不同分层比下的火焰模式和稳定机理,并揭示了流场结构沿轴向的定量演化规律。研究结果表明,提高分层比可以改变分层旋流火焰中火焰面相互作用模式,使主火焰的稳定机理由接触点火变为融合点火机理。同时分层比也会改变火焰释热区的位置,使流场结构以及脱落旋涡的空间分布发生改变。应用旋涡识别方法定量提取了脱落旋涡的位置,获得了内剪切层中脱落旋涡的空间分布和轴向演化规律。
High-speed laser diagnostic system was applied to study the structure and dynamics of a centrally staged stratified swirling flame.A high repetition rate burst mode laser with two amplifier chains was employed in this study to provide 20 kHz laser pulses for the joint planar laser induced fluorescence(PLIF)and particle image velocimetry(PIV)measurement to track the flow/heat release rate and flow-flame front dynamics.The stratification ratio(SR)plays a central role to flame stabilization and instantaneous flow structure in stratified swirling flame.The effects of the SRlead to different flame-flame interaction patterns and locations of heat release regions.Two pilot flame stabilization patterns were identified,namely attaching ignition and merged ignition.The SR also changes the structures of flow fields and spatial distributions of shedding vortices.The quantitative evolution of the flow field structure along axial direction was studied.A vortex identification method was applied to extract the locations of shedding vortices,obtaining the spatial distribution and axial evolution of shedding vortices in inner shear layer.
作者
王思睿
刘训臣
李磊
韩啸
张弛
齐飞
WANG Sirui;LIU Xunchen;LI Lei;HAN Xiao;ZHANG Chi;QI Fei(Shanghai Jiao Tong University,Shanghai 200240,China;Beihang University,Beijing 100191,China)
出处
《空气动力学学报》
CSCD
北大核心
2020年第3期619-628,共10页
Acta Aerodynamica Sinica
基金
国家科技重大专项(2017-III-0004-0028)
国家自然基金(9194130001)。
关键词
分层比
中心分层旋流火焰
多参数同步测量
火焰面相互作用模式
流动结构
stratification ratio
centrally staged stratified swirling flames
multi-parameter simultaneous measurements
flame-flame interaction patterns
flows structures
