Effects of pressure on instability and cellularity of propagating spherical laminar flames: 1st report, cell formation and critical Peclet number
Effects of pressure on instability and cellularity of propagating spherical laminar flames: 1st report, cell formation and critical Peclet number
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压力对传播球形层流火焰的不稳定性和细胞结构的影响：第一份报告，细胞形成和临界佩克莱特数
DOI：
10.1299/kikaib.70.2649
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发表时间：
2004
期刊：
影响因子：
--
通讯作者：
Yukihide Nagano
中科院分区：
文献类型：
--
作者：
T. Kitagawa;T. Ogawa;Yukihide Nagano
本文研究了当量比为0.8 ~ 1.3、初始压力为0.10 ~ 0.50MPa的甲烷和丙烷-空气混合气体传播球形层流火焰的不稳定性引起的胞腔结构。Markstein数被用来量化的当量比和压力的混合物上的细胞由于火焰不稳定性的影响。临界Peclet数，或由火焰厚度归一化的临界火焰半径，在该单元格被创建在整个层流火焰表面上，随着甲烷混合物的当量比的减小而减小，并且随着丙烷混合物的当量比的增加而减小。在所有当量比下，随着初始压力的增加，它都减小。随着Markstein数的减少，它也减少。当Peclet数较大时，火焰拉伸不再稳定，但正的火焰拉伸会抑制Darrieus-Landau火焰的不稳定性。特别是当Markstein数为负值时，即使Peclet数很小，火焰也不稳定。
Cellularity of the propagating spherical laminar flames induced by the flame instability was studied for methane and propane-air mixtures at the equivalence ratios from 0.8 to 1.3 and the initial pressure from 0.10 to 0.50 MPa. The Markstein number was employed to quantify the effects of the equivalence ratio and the pressure of the mixture on the cellularity due to the flame instability. The critical Peclet number, or the critical flame radius normalized by the flame thickness, at which the cells are created over the entire laminar flame surface, decresed with decreasing the equivalence ratio for the methane mixture and decreased with increasing the equivalence ratio for the propane mixture. It decreased with increasing the initial pressure at all the equivalence ratios. It decreased as the Markstein number decreased. The flame was no longer stabilized by the flame stretch at the large Peclet number though the positive flame stretch will restrain the Darrieus-Landau flame instability. Especially with the negative Markstein number, the flame was unstable even at the small Peclet number.