Song Yifan, Zhang Qi
State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, China.
State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, China.
J Hazard Mater. 2018 Jul 5;353:62-69. doi: 10.1016/j.jhazmat.2018.03.052. Epub 2018 Mar 29.
The traditional defence against propagating gas explosions is the application of dry rock dust, but not much quantitative study on explosion suppression of rock dust has been made. Based on the theories of fluid dynamics and combustion, a simulated study on the propagation of premixed gas explosion suppressed by deposited inert rock dust layer is carried out. The characteristics of the explosion field (overpressure, temperature, flame speed and combustion rate) at different deposited rock dust amounts are investigated. The flame in the pipeline cannot be extinguished when the deposited rock dust amount is less than 12 kg/m. The effects of suppressing gas explosion become weak when the deposited rock dust amount is greater than 45 kg/m. The overpressure decreases with the increase of the deposited rock dust amounts in the range of 18-36 kg/m and the flame speed and the flame length show the same trends. When the deposited rock dust amount is 36 kg/m, the overpressure can be reduced by 40%, the peak flame speed by 50%, and the flame length by 42% respectively, compared with those of the gas explosion of stoichiometric mixture. In this model, the effective raised dust concentrations to suppress explosion are 2.5-3.5 kg/m.
传统的防止瓦斯爆炸传播的方法是使用干式岩粉，但对岩粉抑爆的定量研究并不多。基于流体动力学和燃烧理论，对沉积惰性岩粉层抑制预混气体爆炸传播进行了模拟研究。研究了不同沉积岩粉量下爆炸场的特性（超压、温度、火焰速度和燃烧速率）。当沉积岩粉量小于12 kg/m时，管道内火焰无法熄灭。当沉积岩粉量大于45 kg/m时，抑爆效果减弱。在18 - 36 kg/m范围内，超压随沉积岩粉量的增加而降低，火焰速度和火焰长度呈现相同趋势。与化学计量混合物的瓦斯爆炸相比，当沉积岩粉量为36 kg/m时，超压可降低40%，火焰峰值速度降低50%，火焰长度降低42%。在该模型中，抑制爆炸的有效扬起粉尘浓度为2.5 - 3.5 kg/m。
