采用flamelet模型分析旋流杯燃烧室近贫油熄火点

针对进口温度388K不变,不同进气速度下对旋流杯燃烧室常压模化实验得到的贫油熄火油气比数据,采用带有详细化学机理的非预混flamelet燃烧模型进行数值模拟,对近贫油熄火点的局部热态流场进行了分析.结果表明:近贫油熄火点时刻,随着油气比的下降,回流涡旋中心和高温度区分离,回流区内气流温度下降,着火点后移,点火距离增加;进气速度的增加和燃油流量的下降,使得回流区回流量增加,回流涡旋中心两侧温差加大,而着火点更靠后,增加了对这种变化的耐受性.

Analysis on swirl cup combustor near lean blow out point with flamelet model

The experimental data on lean blow out fuel/air ratio of a single-dome swirl cup combustor was obtained at 388 K inlet temperatures and atmospheric pressure with different inlet air velocities.Using flamelet combustion model with detailed chemical mechanism,numerical simulations were performed to get the details of local hot flow field.Results show that,near the lean blow out point,with the decline of fuel/air ratio,the vortex core is separated from high temperature zone,and the temperature in recirculation zone drops,and the ignition point moves backward,so the ignition distance increases.With the increase of inlet air velocity and decrease of the fuel mass flow rate,the mass flow rate of the recirculation and the temperature difference between two sides of the vortex core become greater,but the ignition point stays further back,showing that the flame has greater tolerance with their difference.