The experimental results indicate that secondary air can accelerate volatile combustion in dilute phase zone and raise temperature here remarkably.

实验结果表明：二次风可以促进挥发分在稀相区的燃烧，对提升稀相区的温度作用明显；

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Below the secondary air inlet is reducing atmosphere combustion zone for big particle. Above the secondary air inlet is oxidizing atmosphere combustion zone.

二次风入口以下为大粒子还原气氛燃烧区，二次风入口以上为小粒子氧化气氛燃烧区。

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