Abstract Buoyant, turbulent diffusion flames anchored on a slot burner in the presence of an isothermal, low-temperature (333 K) wall have been numerically simulated. A laminar smoke point based subgrid (flamelet) radiation model has been applied toward estimation of overall radiant fractions and radiant power distributions of the ethylene fires. The model uses a turbulent micro-scale strain rate and an enthalpy defect that influence the flamelet soot radiation. In the presence of the isothermal, low-temperature wall, the radiant fractions of the fires are observed to decrease along with a reduction of their peak radiant power output. Predicted flame heights, radiant fractions and radiant power distributions are found to reproduce observed experimental trends and exhibit quantitative agreement with measurements. Comparison of radiant power distributions are also made for fires adjacent to high-temperature (1000 K) isothermal and adiabatic walls and peak radiant power output for both scenarios are found to be higher compared to the isothermal, low-temperature wall-bounded fire.

中文翻译：

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浮力湍流壁面扩散火焰烟尘辐射的数值模拟

摘要 在等温、低温 (333 K) 壁存在的情况下，锚定在槽式燃烧器上的浮力湍流扩散火焰已经进行了数值模拟。基于层流烟点的子网格（火焰）辐射模型已应用于估计乙烯火灾的整体辐射分数和辐射功率分布。该模型使用湍流微尺度应变率和影响火焰烟尘辐射的焓缺陷。在等温、低温壁存在的情况下，观察到火灾的辐射部分随着其峰值辐射功率输出的降低而降低。发现预测的火焰高度、辐射分数和辐射功率分布可再现观察到的实验趋势并显示出与测量值的定量一致性。