Interaction of turbulence and scalar fields in premixed flames
Interaction of turbulence and scalar fields in premixed flames
复制标题
预混火焰中湍流与标量场的相互作用
DOI：
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发表时间：
2006
期刊：
影响因子：
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通讯作者：
R. Grout
中科院分区：
文献类型：
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作者：
N. Swaminathan;R. Grout
研究了预混火焰中湍流与进动变量c场的相互作用。这种相互作用的特征是相关性c，ieijc，j‘，其中overbar表示适当的平均过程，c，i是c在空间方向i上的梯度，而eij是湍流应变率。通过湍流预混火焰中标量梯度大小平方的输运方程，认识到这一项的重要性。结果还表明，上述关联式构成了火焰面密度Σ方程中出现的切向应变速率的自然部分。众所周知，这种关联是负的，表明不可压缩湍流通过标量梯度与最大压缩主应变率的优先排列产生标量梯度。这种物理图像通常也适用于湍流预混火焰。与此相反，对有火焰的湍流预混火焰的直接数值模拟数据的分析是正确的。
The interaction of turbulence with progress variable, c, field in a premixed flame is studied. This interaction is characterized by the correlation c,ieijc,j¯, where the overbar denotes an appropriate averaging process, c,i is the gradient of c in spatial direction i and eij is the turbulence strain rate. The importance of this term is recognized via a transport equation for the square of the magnitude of the scalar gradient in turbulent premixed flames. It is also shown that the above correlation forms a natural part of the tangential strain rate which appears in the flame surface density, Σ, equation. It is well known that this correlation is negative signifying the scalar gradient production by incompressible turbulence via the preferential alignment of the scalar gradient with the most compressive principal strain rate. This physical picture is commonly adopted for turbulent premixed flames also. Contrary to this, analyses of direct numerical simulation data for a turbulent premixed flame having flame...