Effects of Turbulent Reynolds Number on Turbulent Scalar Flux Modeling in Premixed Flames Using Reynolds-Averaged Navier-Stokes Simulations
Effects of Turbulent Reynolds Number on Turbulent Scalar Flux Modeling in Premixed Flames Using Reynolds-Averaged Navier-Stokes Simulations
复制标题
湍流雷诺数对使用雷诺平均纳维-斯托克斯模拟的预混火焰湍流标量通量建模的影响
DOI：
10.1080/10407782.2014.955375
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
Chakraborty N
中科院分区：
文献类型：
--
作者：
Chakraborty N
利用自由传播湍流预混火焰的直接数值模拟数据库，分析了湍流雷诺数（Ret）对湍流标量通量（TSF）统计行为和模型的影响。一系列不同的价值观的Retis认为，其中的Damköhler和Karlovitz数被修改独立于彼此带来的变化的Ret。研究发现，Ret的变化并不改变TSF输运方程各项的定性行为，但它们对TSF输运的相对贡献受到一定程度的影响。使用代数和运输方程为基础的封闭的TSF建模的影响Reton详细解决。结果表明，现有的代数模型的模型参数，以及湍流输运，压力梯度和反应速率项的TSF传输方程中的模型，都表现出Retdependence小值的Retbut都假定渐近值为Ret≥ 50。相比之下，组合分子扩散项的模型参数对湍流Ret的变化不敏感。现有的模型代数和运输方程为基础的封闭TSF已被修改，以考虑到所观察到的Retdependence。
The influence of turbulent Reynolds number (Ret) on the statistical behavior and modeling of turbulent scalar flux (TSF) has been analyzed using a direct numerical simulation database of freely propagating turbulent premixed flames. A range of different values of Retis considered in which the Damköhler and Karlovitz numbers are modified independent of each other to bring about the variation of Ret. It has been found that the qualitative behavior of the various terms of the TSF transport equation does not change by the variation of Ret, but their relative contributions to the transport of TSF are affected to some extent. The effects of Reton the modeling of the TSF using both algebraic and transport equation-based closures are addressed in detail. It is demonstrated that model parameters for an existing algebraic model, and the models for turbulent transport, pressure gradient and the reaction rate terms in the TSF transport equation, all exhibit Retdependence for small values of Retbut all assume asymptotic values for Ret≥ 50. By contrast, the model parameters for the combined molecular diffusion term are found to be insensitive to the variation of turbulent Ret. Existing models for algebraic and transport equation-based closures of TSF have been modified to account for the observed Retdependence.