超细水雾对甲烷-煤尘爆炸过程的抑制机理研究

Inhibition Mechanism of Ultra-fine Water Mist on Methane-Coal Dust Hybrid Explosion

中文关键词: 甲烷-煤尘爆炸  超细水雾  传播规律  煤尘颗粒

英文关键词: Methane-coal dust explosion  Ultra-fine water mist  Propagation law  Coal dust particles

中文摘要:

      为了研究超细水雾对甲烷-煤尘混合爆炸过程的作用规律，本文在20L长方体爆炸装置进行了抑爆实验。同时基于甲烷气体、雾滴颗粒、煤尘颗粒在受限空间内的蒸发、脱挥发、燃烧的过程，建立了超细水雾抑制甲烷-煤尘混合爆炸的数学模型。同实验进行对比，数值模拟得到的爆炸压力可准确地反映实际爆炸过程。结果表明，超细水雾的加入改变了爆炸的传播规律。与无抑制的甲烷-煤尘混合爆炸相比，加入超细水雾降低了已燃区的气相温度与煤尘颗粒温度，并推迟了火焰阵面沿轴向的传播过程。煤尘颗粒的温度分布表明，超细水雾在推迟煤尘颗粒升温过程的同时，反应区煤尘颗粒的中位温度也明显降低。随着超细水雾的抑制浓度不断增加，其对甲烷-煤尘混合爆炸的气相燃烧过程和颗粒脱挥发及燃烧过程的抑制效果也不断增强。研究有助于对工业生产中甲烷-煤尘爆炸的强度预测和水雾抑制提供参考。

英文摘要:

      In order to study the effect of ultra-fine water mist on the methane-coal dust mixed explosion process, an explosion suppression experiment was carried out in a 20L cuboid explosive device. Based on the process of evaporation, devolatilization and combustion of methane gas, droplet particles and coal dust particles in a confined space, a mathematical model for suppressing methane-coal dust mixed explosions by ultra-fine water mist was established. Compared with the experiment, the explosion pressure obtained by numerical simulation can accurately reflect the actual explosion process. The results show that the addition of ultrafine water mist changes the propagation law of the explosion. Compared with the unsuppressed methane-coal dust mixed explosion, the addition of ultra-fine water mist reduces the gas phase temperature and coal dust particle temperature in the burned zone, and delays the propagation process of the flame surface along the axial direction. The temperature distribution of coal dust particles shows that the ultra-fine water mist delays the heating process of coal dust particles, and the median temperature of coal dust particles in the reaction zone also decreases significantly. As the concentration of ultrafine water mist increases, its inhibitory effect on the gas-phase combustion process and particle devolatilization and combustion process is also continuously enhanced. The research provides a reference for the intensity prediction and water mist suppression of methane-coal dust explosions in industrial production.