中文摘要：

为分析煤粉粉尘的爆炸特性,利用20 L爆炸球测试装置与Fluent软件,试验研究煤粉粒径、质量浓度对煤粉云最大爆炸压力、爆炸指数的影响。结果表明,当试验环境温度为293-303 K时,点火能量为10 k J,粒径为26,73和115μm等3种粉尘云的最大爆炸压力均随着粉尘质量浓度的增加先升后降,在350 g/m3处达到最大值。同一粉尘质量浓度下,最大爆炸压力、爆炸指数均随着粒径的减小而增大。在60-120 ms时间内,粒径为26μm、质量浓度为350 g/m3的粉尘颗粒在球体内能保持一定的稳定状态,60 ms左右扩散达到相对均匀状态。爆炸后,燃烧最高温度为2 060 K,未燃区温度由300 K上升至375 K。粒径为26μm的煤粉尘云爆炸危险性等级为Ⅱ级,粒径为73和115μm的煤粉尘云爆炸危险性等级为Ⅰ级。

英文摘要：

To analyze the explosion characteristics of coal dust,the effects of particle size and concentration of coal on the maximum explosion pressure,explosion index were investigated by using a 20 L explosive ball test device and the Fluent software. The results show that in the experimental environment 293-303 K,when the ignition energy is 10 k J,with the increase of dust concentration,the maximum explosion pressures of three different clouds of coal dust,particle sizes of which are 26,73 and 115 μm respectively,rise first and drop afterwards,reaching their maxima at 350 g / m3,that at the same dust concentration,the maximum explosion pressure and the explosion index all increase with the decrease of the particle size,that the particle size of 26 μm,concentration of 350 g / m3 coal dust can maintain a relatively stable state during the period of 60-120 ms,and the diffusion reaches a relatively uniform state in around 60 ms,that after the explosion,the highest temperature in the combustion zone reached 2 060 K,and the unburned area temperature increased from 300 K to 375 K,and that 26 μm dust cloud explosion hazard is rated gradeⅡ,73 and 115μm dust clouds explosion hazards are rated gradeⅠ.