Sandia Flame D taken as an example, the influence of turbulence-radiation interaction (TRI)caused by temperature fluctuations on radiation source term was discussed. Based on the turbulence and combustion modeling with realizable k-ε turbulence model, probability density function (PDF)model and detailed chemical mechanism,radiation heat transfer was simulated with P 1 approximation and gray band approximation of narrow-band model. The correlation between fluctuations of absorption coefficient and those of Planck function was simulated using Reynolds decomposition, Taylor series expansion and solution to transport equations of temperature fluctuations. Optically thin fluctuation approximation (OTFA) was used simultaneously, which neglected the correlation between fluctuations of absorption coefficient and those of radiation intensity. The results show that thermal radiation increases due to TRI caused by temperature fluctuations. The computed results are close to the experimental data when TRI effect is considered in the simulation of thermal radiation source term. Therefore, TRI effect should be considered in the estimation of thermal radiation source term in turbulent jet flame simulation.%以美国Sandia实验室Flame D为研究对象,探讨由温度脉动引起的湍流辐射交互作用(TRI)对湍流射流火焰模拟中辐射源项的影响.采用κ-ε湍流模型和标量概率密度函数(PDF)结合详细的化学反应机理模拟燃烧过程,球谐函数(P1近似)法、窄带模型的灰带近似模拟辐射换热.吸收系数脉动与辐射强度脉动关联项采用湍流涡团光学薄脉动近似(OTFA)处理,吸收系数与普朗克函数关联项采用雷诺分解、泰勒级数展开结合温度脉动输运方程求解.结果表明,由温度脉动引起的TRI增强了湍流射流火焰的辐射换热,对辐射源项的处理考虑TRI的影响时,数值模拟结果更接近实验值,因此在湍流火焰的辐射换热模拟中不容忽略.
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