旋流对煤粉燃烧NO排放影响的数值模拟

NUMERICAL SIMULATION OF EFFECT OF SWIRL ON NO FORMATION IN COAL COMBUSTION

本文用基于HCN释放的简化Solomon模型的NO生成湍流反应的统一二阶矩代数模型(AUSM)和煤粉燃烧的双流体模型,对不同旋流数下煤粉燃烧器内两相流动,煤粉燃烧和NO生成进行了数值模拟。模拟结果和文献中实验结果符合很好。模拟结果指出,随着旋流数的增加,NO的排放先减少后增加,燃尽率先增加后减小,和气体燃烧中得到的规律类似。

The gas-particle flows, coal combustion and NO formation in a coal burner with different swirl numbers are simulated using a unified second-order moment algebraic model of NO turbulent reaction with Solomon's model of HCN release and a two-fluid model of coal combustion. The prediction results are in good agreement with the experimental results reported in references. The results indicate that as the swirl number increases, the NO emission at first decreases and then increases, while the burnout rate at first increases and then decreases. This phenomena is similar to that obtained in gas combustion.