惰化剂粒径对铝粉火焰传播特性影响的实验研究

为探索惰化剂粒径对可燃工业粉尘火焰传播特性的影响，通过建立竖直粉尘燃烧管道实验平台，在碳酸氢钠质量分数为30%的惰化条件下，就碳酸氢钠粒径对铝粉燃烧火焰传播特性的影响进行了实验研究。结果表明:平均粒径为30 μm的碳酸氢钠粉体对平均粒径为15 μm的铝粉的火焰传播速度具有较好的抑制作用，惰性粉体与可燃工业粉尘应存在粒度匹配效应；碳酸氢钠粉体对铝粉火焰温度的惰化抑制效果与其粒径呈反比关系；碳酸氢钠粉体会减小铝粉火焰预热区厚度，预热区厚度随碳酸氢钠粒径的增加先减小后增大。此外，分析了碳酸氢钠粒径对铝粉火焰传播特性影响的作用机理。

Effects of inerting agent with different particle sizes on the flame propagation of aluminum dust

To explore the influence of the inerting agent with different particle sizes on the flame propagation of the combustible industrial dust,by establishing a vertical dust combustion pipe experiment platform,we investigated the effects of the particle size of sodium bicarbonate on the characteristics of the burning flame propagation of aluminum powder.The results show that,under the condition of 30％ mass fraction of sodium bicarbonate,the sodium bicarbonate powder with an average particle size of 30μm has a good inhibitory effect on the flame propagation speed of aluminum powder with an average particle size of 15μm,and there exists a correlation between the particle size of the inerting powder and the combustible industrial dust.The inerting inhibiting effect of sodium bicarbonate powder on the flame temperature of aluminum is inversely proportionate to its particle size.It was found that sodium bicarbonate powder can decrease the thickness of the preheating zone of aluminum powder flame,which decreases at first and then increases with the increase of the particle size of the sodium bicarbonate.Finally,we also examined the mechanism underlying the influence of sodium bicarbonate particle size on the flame propagation of aluminum powder.