摘要
对低NOx 燃烧器从试验和数值模拟两个方面进行了研究 ,结果表明 :低NOx 燃烧器浓淡两侧的速度比与管道气体速度和分隔板开缝与否均无关 ,大小为 1 .1 4～ 1 .3 0 ,速度差为 2 .3 7m/s(管道气体速度U =1 8m/s时 )～ 7.90m/s(管道气体速度U =2 8m/s时 ) ;低NOx 燃烧器分隔板开缝时 ,相对不开缝结构阻力增加 1 .3 % (1 80°扭曲分隔板 )～ 1 0 % (平直分隔板 ) ;低NOx 燃烧器分隔板前布置阻挡锥时 ,阻力再增加1 0 .1 % (1 80°扭曲分隔板 )～ 1 2 .1 % (平直分隔板 ) ;低NOx 燃烧器浓淡两侧的固气比与分隔板有无开缝无关 ,浓侧煤粉射流的固气比随气流速度增大而增大 ,淡侧射流的固气比随气流速度的增大而减小 ,浓淡两侧的固气比随管道煤粉固气比的增大而增大。常规直流煤粉燃烧器加装不开缝的平直分隔板时 ,阻力增加1 7.7% ,加装不开缝的 1 80°扭曲分隔板时 ,阻力增加 71 .6%。低NOx 燃烧器的分隔板开缝时 ,浓淡两侧的静压平衡 ,浓淡两侧的湍动能都增加 ,浓侧湍动能增加大约 2 0 %。
Experiment & numerical simulation of low NO x Pulverized-coal Burner have been conducted with 8 kinds of blades. Results show that the velocity rate of de nse to lean pulverized-coal stream of low NO x pulverized-coal burner is independent with duct air velocity or blades with mid-split or without it. Its magnitude is 1.14～1.30 and velocity difference is 2.37 m/s (coal piping air vel o city is 18.0 m/s)～7.90 m/s (coal piping air velocity is 28 m/s). If blades of l o w NO x pulverized-coal burner have been cut with mid-split, its resistanc e increases 10 % (blade in flat)～1.3 %(blade with 180° helix). If a block is i n stalled before blade position, its resistance adds 12.1 % (blade in flat)～10.1 % (blade with 180° helix). The pulverized-coal concentration of dense or lean s tream has nothing to do with blades in mid-split or otherwise. The pulverized-coal concentra tion of dense stream is increased when duct air velocity is added, but it of lea n stream is reduced. The concentration of dense or lean stream is all increased when duct pulverized-coal concentration is added. If a flat blade without mid- split is installed in a conventional pulverized-coal burner, its resistance inc reases 17.7 %, and as a 180° helix blade is fixed, its resistance adds 71.6 %. a blade with mid-split of low NO x Burner is applied, static pressure of d ense stream is balanced with it of lean stream, and their turbulent kinetic ener gy are enhanced, it of the dense stream is increased about 20 %.
出处
《锅炉技术》
北大核心
2005年第1期43-48,56,共7页
Boiler Technology
关键词
低NOX燃烧器
180°开缝扭曲分离板
固气比
速度
阻力
low NO x pulverized-coal burner
180° helix blade with mid-split
rate of solid to air
velocity
resistance
