A flamelet-based subgrid soot-radiation model, which applies the laminar smoke point concept for soot formation, is further developed to account for varying oxygen concentration (${\chi }_{O_2}$) and applied in radiation modeling of buoyant, turbulent diffusion flames. The model is verified against experimental data for laminar flames. A lookup table of radiant emission fractions is developed by parametrizing the flamelet model with a range of strain rates, enthalpy defect (prior heat loss) and ${\chi }_{O_2}$. The three-dimensional lookup table is then used in the large eddy simulations (LES) to predict the turbulent flame-sheet radiant emission. LES of optically-thin, buoyant, turbulent ethylene diffusion flames of 10 and 15 kW heat release rates (HRR) are conducted for ${\chi }_{O_2}$in the range of 0.13 - 0.21. With decreasing ${\chi }_{O_2},$the overall radiant fraction and the peak radiant power output from the flames are shown to decrease, as would be expected. Predicted results for radiant power distributions, overall radiant fraction and temperatures show reasonably good comparison against experimental data.

基于火焰的亚网格烟尘辐射模型得到了进一步发展，该模型将层流烟点概念应用于烟尘形成，以解决氧气浓度变化的问题（${\chi }_{{Ø}_2}$）并应用于浮力湍流扩散火焰的辐射建模。针对层流火焰的实验数据验证了该模型。通过用一系列应变率，焓缺陷（先有热量损失）和${\chi }_{{Ø}_2}$。然后，在大型涡流模拟（LES）中使用三维查找表来预测湍流的火焰片辐射。进行10 kW和15 kW放热率（HRR）的光学稀薄，浮力的湍流乙烯扩散火焰的LES${\chi }_{{Ø}_2}$在0.13-0.21的范围内。随着减少${\chi }_{{Ø}_2}，$如预期的那样，火焰的总辐射分数和峰值辐射功率显示出下降的趋势。辐射功率分布，总辐射分数和温度的预测结果与实验数据显示出相当好的对比。