煤尘二次爆炸特性研究

Research on secondary explosion characteristic of coal dust

利用20L球形爆炸装置研究了煤尘浓度、煤尘粒径和点火能量对煤尘二次爆炸特性的影响,并与煤尘一次爆炸特性进行了对比分析。结果表明:随着煤尘浓度的增加,煤尘二次爆炸最大压力和爆炸压力最大上升速率均先增大后减小,一次爆炸与二次爆炸的最大压力差先减小后增大,一次爆炸与二次爆炸的压力最大上升速率差先减小后增大再减小;随着煤尘粒径的减小,煤尘二次爆炸最大压力和爆炸压力最大上升速率不断增大,一次爆炸与二次爆炸的最大压力差及压力最大上升速率差均先增大后减小;随着点火能量的增加,煤尘二次爆炸最大压力和爆炸压力最大上升速率,以及一次爆炸与二次爆炸的最大压力差及压力最大上升速率差均呈增大的变化趋势;煤尘二次爆炸最大压力和爆炸压力最大上升速率与一次爆炸时相比均减小;煤尘浓度为煤尘二次爆炸特性与一次爆炸产生差异的主要影响因素。

Influence of concentration, particle size and ignition energy of coal dust on sccondaryexplosion characteristic of coal dust were studied by use of 20 L spherical explosion device, and thesccondary explosion characteristic of coal dust was compared with the first explosion characteristic of coal dust. The results show that with the increase of coal dust concentration, the maximum pressure and themaximum rising rate of pressure of sccondary explosion of coal dust increase firstlymaximum pressure difference between the first explosion and sccondary explosion decreases firstly and then increases, and the maximum rising rate difference of pressure between the first explosion and sccondary explosion decreases firstly, then increases and decreases lastly; with the decrease of coal dustparticle size, the maximum pressure and the maximum rising rate of pressure of sccondary explosion of coal dust gradually increase, the maximum pressure difference and the maximum rising rate difference ofpressure between the first explosion and secondary explosion increase firstly and then decrease; with theincrease of ignition energy, the maximum pressure and the maximum rising rate of pressure of secondary explosion of coal dust, and the maximum pressure difference and the maximum risingpressure between the first explosion and secondary explosion increase; the maximum pressure and the maximum rising rate of pressure of secondary explosion of coal dust is smaller than that of the first explosion; coal dust concentration is the main influence factor on the characteristic difference betweensecondary explosion and the first explosion of coal dust.