【摘要】 通过实验和用湍流燃烧二阶矩概率密度模型对不同旋流数下甲烷-空气湍流燃烧和NO生成进行了研究。在燃料中加入少量氨模拟燃料氮。研究结果表明,随旋流数的增大（由0到1）,热NO排放先上升后下降,而总NO和燃料NO排放则先下降后上升。旋流数增大使湍流强度先下降然后稍有上升,使进口附近温度先上升然后稍有下降。热NO的生成受温度的影响更大而燃料NO的生成受湍流的影响更大。更多还原

【Abstract】 The effect of swirl number on NO formation in methane-air turbulent combustion is studied by experiments, in which a small amount of ammonia is added to the fuel to simulate fuel nitrogen, and by numerical simulation, using the second-order moment-PDF turbulence-chemistry model. Both predictions and experiments show that as the swirl number increases from 0 to 1, the thermal NO at first increases and then decreases, and in contrast the fuel NO at first decreases and then increases. The increase of swirl number leads to a first decrease and then an increase of turbulence intensity, and a first increase and then a slight decrease of temperature near the exit. These results indicate that the thermal NO is predominantly affected by temperature whereas the fuel NO is predominantly affected by mixing via turbulence.更多还原