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；
2
Below the secondary air inlet is reducing atmosphere combustionzone for big particle. Above the secondary air inlet is oxidizing atmosphere combustionzone.