A mixing model for turbulent reactive flows based on Euclidean minimum spanning trees
A mixing model for turbulent reactive flows based on Euclidean minimum spanning trees
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DOI：
10.1016/s0010-2180(98)00023-6
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发表时间：
1998-12
影响因子：
4.4
通讯作者：
S. Subramaniam;S. Pope
中科院分区：
文献类型：
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作者：
S. Subramaniam;S. Pope
在基于速度和组分联合概率密度函数（jpdf）的输运方程模拟湍流反应流时，由于对流和反应而引起的流体组分变化被精确处理，而分子混合必须被模拟。提出了一种新的混合模型，这是本地的组成空间，并试图解决同时混合和反应的流动中遇到的问题。在该模型中，颗粒组成的变化是由颗粒之间的相互作用沿着的欧氏最小生成树（埃姆斯特）的组成空间中构建的边缘。在均匀湍流中，在平均标量梯度的影响下，被动标量的演化模型问题所得到的结果，与Alfrevat和Warhaft（1983）的实验结果相当一致。将该模型应用于Norris和Pope（1991）提出的扩散火焰试验模型问题，其性能上级现有模型。新的埃姆斯特混合模型的基本特征是在成分空间中局部模拟混合，这是它在扩散火焰试验中取得成功的原因。
In modeling turbulent reactive flows based on the transport equation for the joint probability density function (jpdf) of velocity and composition, the change in fluid composition due to convection and reaction is treated exactly, while molecular mixing has to be modeled. A new mixing model is proposed, which is local in composition space and which seeks to address problems encountered in flows with simultaneous mixing and reaction. In this model the change in particle composition is determined by particle interactions along the edges of a Euclidean minimum spanning tree (EMST) constructed in composition space. Results obtained for the model problem of passive scalars evolving under the influence of a mean scalar gradient in homogeneous turbulence are found to be in reasonable agreement with experimental findings of Sirivat and Warhaft (1983). The model is applied to the diffusion flame test model problem proposed by Norris and Pope (1991) and its performance is found to be superior to that of existing models. The essential feature of the new EMST mixing model, which accounts for its success in the diffusion flame test, is that mixing is modeled locally in composition space.