Large-Eddy Simulation of Turbulence-Radiation Interactions in a Turbulent Planar Channel Flow
Large-Eddy Simulation of Turbulence-Radiation Interactions in a Turbulent Planar Channel Flow
复制标题
DOI：
10.1115/1.3085875
复制
发表时间：
2009-06-01
影响因子：
--
通讯作者：
Haworth, Daniel C.
中科院分区：
文献类型：
--
作者：
Gupta, Ankur;Modest, Michael F.;Haworth, Daniel C.
对两个无限平行固定板之间的平面湍流通道流进行了大涡模拟 (LES)。通过与非反应情况文献中的直接数值模拟数据进行比较，确定了 LES 代码在预测正确的湍流速度和被动温度场统计数据方面的能力和局限性。模拟了燃料流和氧化剂流之间的混合和化学反应（无限快），以在流中产生较大的成分和温度波动；这里的成分和温度不影响流体动力学（单向耦合）。使用球谐函数 (P1) 方法求解辐射传递方程，辐射特性对应于虚构的灰色气体，其具有与成分和温度相关的普朗克平均吸收系数，模拟典型的碳氢化合物-空气燃烧产物的吸收系数。已经针对不同的光学厚度进行了模拟。在没有化学反应的情况下，辐射显着改变了平均温度分布，但温度波动和湍流-辐射相互作用（TRI）很小，这与早期的发现一致。化学反应增强了成分和温度波动，因此增强了 TRI 的重要性。 TRI 对发射和吸收的贡献已被隔离并量化为光学厚度的函数。
Large-eddy simulation (LES) has been performed for planar turbulent channel flow between two infinite, parallel, stationary plates. The capabilities and limitations of the LES code in predicting correct turbulent velocity and passive temperature field statistics have been established through comparison to direct numerical simulation data from the literature for nonreacting cases. Mixing and chemical reaction (infinitely fast) between a fuel stream and an oxidizer stream have been simulated to generate large composition and temperature fluctuations in the flow; here the composition and temperature do not affect the hydrodynamics (one-way coupling). The radiative transfer equation is solved using a spherical harmonics (P1) method, and radiation properties correspond to a fictitious gray gas with a composition- and temperature-dependent Planck-mean absorption coefficient that mimics that of typical hydrocarbon-air combustion products. Simulations have been performed for different optical thicknesses. In the absence of chemical reactions, radiation significantly modifies the mean temperature profiles, but temperature fluctuations and turbulence-radiation interactions (TRI) are small, consistent with earlier findings. Chemical reaction enhances the composition and temperature fluctuations and, hence, the importance of TRI. Contributions to emission and absorption TRI have been isolated and quantified as a function of optical thickness.