Estimation of three-dimensional flame surface densities from planar images in turbulent premixed combustion
Estimation of three-dimensional flame surface densities from planar images in turbulent premixed combustion
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DOI：
10.1007/s00348-010-0851-y
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发表时间：
2010-03
影响因子：
2.4
通讯作者：
D. Veynante;G. Lodato;P. Domingo;L. Vervisch;E. Hawkes
中科院分区：
文献类型：
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作者：
D. Veynante;G. Lodato;P. Domingo;L. Vervisch;E. Hawkes
湍流运动本质上是三维的，而广泛应用于湍流燃烧的平面成像技术只能获得二维信息。例如，为了从平面图像中提取火焰表面密度，这是一些湍流燃烧模型的关键成分，隐含地假设了瞬时二维流动，忽略了未解决的火焰前缘褶皱。这里的目的是从二维测量中估计火焰表面密度，假设(1)流动在统计上是二维的；(2)测量平面是平均流动的对称平面，无论是通过平移(例如狭缝燃烧器中均匀的第三方向)还是通过旋转(轴对称流动，例如射流)和(3)火焰在横向方向上的运动是相似的。然后，根据已知量对未知的火焰锋面起皱进行建模。对于所有三维量都已知的直接数值模拟(DNS)数据，获得了很好的一致性，但需要在其他条件下(较大的DNS，实验)进行验证。
Turbulence motions are, by nature, three-dimensional while planar imaging techniques, widely used in turbulent combustion, give only access to two-dimensional information. For example, to extract flame surface densities, a key ingredient of some turbulent combustion models, from planar images implicitly assumes an instantaneously two-dimensional flow, neglecting the unresolved flame front wrinkling. The objective here is to estimate flame surface densities from two-dimensional measurements assuming that (1) the flow is statistically two dimensional; (2) the measuring plane is a plane of symmetry of the mean flow, either by translation (homogeneous third direction as in slot burners for example) or by rotation (axi-symmetrical flows such as jets) and (3) flame movements in transverse directions are similar. The unknown flame front wrinkling is then modelled from known quantities. An excellent agreement is achieved against direct numerical simulation (DNS) data where all three-dimensional quantities are known, but validations in other conditions (larger DNS, experiments) are required.