Evolution and scaling of the peak flame surface density in spherical turbulent premixed flames subjected to decaying isotropic turbulence
Evolution and scaling of the peak flame surface density in spherical turbulent premixed flames subjected to decaying isotropic turbulence
复制标题
经受衰减各向同性湍流的球形湍流预混火焰中峰值火焰表面密度的演变和缩放
DOI：
10.1016/j.proci.2020.06.042
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发表时间：
2020
影响因子：
3.4
通讯作者：
Bisetti, Fabrizio
中科院分区：
文献类型：
--
作者：
Kulkarni, Tejas;Bisetti, Fabrizio
湍流火焰刷内的峰值火焰面密度是小火焰区湍流预混燃烧模型的核心。这项工作研究的峰值表面密度在球形膨胀湍流预混火焰的帮助下，在不同的雷诺数和Karlovitz数的值的直接数值模拟的演变。火焰在封闭容器内以衰减的各向同性湍流传播。湍流运输，运输由于平均速度梯度，和火焰拉伸上的峰值表面密度的影响进行了识别和分析的基础上的火焰表面密度函数的运输方程的特点。这三种机制是由不同的流动时间尺度;湍流运输的涡流周转时间，平均运输的时间尺度相关的压力上升在封闭的腔室，和火焰拉伸的Kolmogorov时间尺度。适当的缩放的条款提出，并显示崩溃的数据，尽管在无量纲组的变化。总的来说，传输项导致表面密度的峰值降低，而火焰拉伸具有相反的效果。在本配置中，两者之间的小的不平衡导致峰值表面密度随时间的指数衰减。的无量纲衰变率被发现是一致的Bray-Moss-Libby模型中定义的尺度的演变。
The peak flame surface density within the turbulent flame brush is central to turbulent premixed combustion models in the flamelet regime. This work investigates the evolution of the peak surface density in spherically expanding turbulent premixed flames with the help of direct numerical simulations at various values of the Reynolds and Karlovitz number. The flames propagate in decaying isotropic turbulence inside a closed vessel. The effects of turbulent transport, transport due to mean velocity gradient, and flame stretch on the peak surface density are identified and characterized with an analysis based on the transport equation for the flame surface density function. The three mechanisms are governed by distinct flow time scales; turbulent transport by the eddy turnover time, mean transport by a time scale related to the pressure rise in the closed chamber, and flame stretch by the Kolmogorov time scale. Appropriate scaling of the terms is proposed and shown to collapse the data despite variations in the dimensionless groups. Overall, the transport terms lead to a reduction in the peak value of the surface density, while flame stretch has the opposite effect. In the present configuration, a small imbalance between the two leads to an exponential decay of the peak surface density in time. The dimensionless decay rate is found to be consistent with the evolution of the wrinkling scale as defined in the Bray-Moss-Libby model.
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影响因子：
3.4
作者：
S. Luca;A. Attili;E. Lo Schiavo;F. Creta;F. Bisetti
通讯作者：
S. Luca;A. Attili;E. Lo Schiavo;F. Creta;F. Bisetti
影响因子：
4.6
作者：
Mei;A. Leonard
通讯作者：
A. Leonard
通过条件分析湍流预混燃烧中最大火焰表面密度与刷厚度的关系
影响因子：
4.6
作者：
K. Huh;Jaesung Kwon;Dongkyu Lee
通讯作者：
Dongkyu Lee
不同刘易斯数下自由传播预混火焰的局部火焰结构和火焰表面密度的表征
影响因子：
1.9
作者：
B. Renou;A. Mura;E. Samson;A. Boukhalfa
通讯作者：
A. Boukhalfa
DOI：
--
发表时间：
2013
期刊：
影响因子：
--
作者：
I. Ahmed;N. Swaminathan
通讯作者：
N. Swaminathan