当前位置: X-MOL 学术J. Energy Inst. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
The effects of aspect ratio on CH4/air flame stability in rectangular mesoscale combustors
Journal of the Energy Institute ( IF 5.6 ) Pub Date : 2019-05-11 , DOI: 10.1016/j.joei.2019.05.003
Zili Yuan , Aiwu Fan

The effects of aspect ratio (α = 1, 2, 3 and 4) of mesoscale rectangular channels on CH4-air flame stability were numerically studied. The results show that at relatively high inlet velocity, the flame is convex (with respect to the upstream) when α ≤ 3; instead it shifts to a W-shaped appearance at α = 4. In addition, the flame blowout limit exhibits a non-monotonic variation and it peaks at α = 3. Our analysis reveals that when α is raised from 1 to 3, both of the heat loss ratio and hydrodynamic perturbation rate are reduced, which favors a larger blowout limit. However, for the channel with α = 4, the perturbation rate of hydrodynamic instability is significantly increased at the flame tip because of the increased wave number, which results from the W-shaped flame front. Consequently, the intensified hydrodynamic instability will lead to a reduction in the flame blowout limit of the channel with α = 4.



中文翻译:

长宽比对矩形中尺度燃烧室CH 4 /空气火焰稳定性的影响

中尺度矩形通道的纵横比(α= 1、2、3和4)对CH 4的影响对空气火焰稳定性进行了数值研究。结果表明,在较高的入口速度下,当α≤3时,火焰是凸形的(相对于上游)。取而代之的是,它在α= 4时转变为W形外观。此外,火焰喷出极限呈现出非单调变化,并且在α= 3时达到峰值。我们的分析表明,当α从1增加到3时,两个热损失率和流体动力扰动率降低,这有利于更大的井喷极限。但是,对于α= 4的通道,由于W形火焰前沿导致的波数增加,因此火焰动力扰动率在火焰尖端显着增加。因此,加剧的水动力不稳定性将导致α= 4的通道的火焰喷出极限降低。

更新日期:2019-05-11
down
wechat
bug