Spatial correlation of heat release rate and sound emission from turbulent premixed flames
Spatial correlation of heat release rate and sound emission from turbulent premixed flames
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湍流预混火焰的热释放率和声发射的空间相关性
DOI：
10.1016/j.combustflame.2012.03.003
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发表时间：
2012
影响因子：
4.4
通讯作者：
Liu Y
中科院分区：
文献类型：
--
作者：
Liu Y
脉动放热速率变化率的两点空间相关性是开放湍流火焰的声发射的核心，在最近的研究中，人们对这种相关性进行了一些尝试。本文通过对统计多维湍流预混火焰直接数值模拟数据的分析，研究了两点相关及其在燃烧噪声中的作用。结果表明，这种关联函数依赖于分离距离和方向，而不依赖于火焰刷子内部的位置。这种相关性可以使用零阶和二阶Hermite-Gauss函数的组合来建模，即常数A和B的形式为[公式：参见正文]的函数，以包括其可能的负值。利用该模型得到的积分关联体积约为0.2δL~3，由立方根得到的长度尺度约为0.6δL，其中δL为层流火焰热厚度。由于观察到了相关性的各向异性，这两个值都比早期研究中报告的值略大。该模型与湍流相关参数K(反应速率变化率的均方根(RMS)值与平均反应速率的比值)一起用于预测明火发出的远场声场。计算的噪声水平与最近报道的测量结果吻合得很好，并显示出对K值的敏感性。
The two-point spatial correlation of the rate of change of fluctuating heat release rate is central to the sound emission from open turbulent flames, and a few attempts have been made to address this correlation in recent studies. In this paper, the two-point correlation and its role in combustion noise are studied by analysing direct numerical simulation (DNS) data of statistically multi-dimensional turbulent premixed flames. The results suggest that this correlation function depends on the separation distance and direction but, not on the positions inside the flame brush. This correlation can be modelled using a combination of Hermite–Gaussian functions of zero and second order, i.e. functions of the form [Formula: see text] for constants A and B, to include its possible negative values. The integral correlation volume obtained using this model is about 0.2δL3with the length scale obtained from its cube root being about 0.6δL, where δLis the laminar flame thermal thickness. Both of the values are slightly larger than the values reported in an earlier study because of the anisotropy observed for the correlation. This model together with the turbulence-dependent parameter K, the ratio of the root-mean-square (RMS) value of the rate of change of reaction rate to the mean reaction rate, derived from the DNS data is applied to predict the far-field sound emitted from open flames. The calculated noise levels agree well with recently reported measurements and show a sensitivity to K values.
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影响因子：
4.7
作者：
S. Kotake;K. Takamoto
通讯作者：
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影响因子：
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作者：
N. Swaminathan;R. Balachandran;G. Xu;A. Dowling
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DOI：
10.1098/rspa.1979.0089
发表时间：
1979
期刊：
Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences
影响因子：
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作者：
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DOI：
10.2514/6.1979-590
发表时间：
1979
期刊：
Investigative ophthalmology
影响因子：
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作者：
A. Dowling
通讯作者：
A. Dowling
影响因子：
2.4
作者：
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