基于20 L球形爆炸装置的煤尘爆炸特性研究

采用标准的20 L爆炸球实验装置，研究了3种不同煤质的煤尘及瓦斯煤尘混合物的爆炸特性，获得了不同实验条件下煤尘的爆炸特征参数，并给出了定量评价。研究结果显示：不同煤质特性煤尘的爆炸特性存在显著差异，在实验选定的粉尘浓度范围内，煤尘的爆炸超压及超压的上升速率随粉尘浓度基本呈先增加后降低的变化趋势；随着爆炸环境初始压力的增加，显著延长了煤尘析出的可燃性挥发分气体的火焰发展期，使得煤尘的爆炸参数随初始压力均呈现升高的变化规律；煤尘的爆炸特性随混合物中瓦斯气体的含量呈先增加后降低的趋势，初始少量瓦斯气体的加入显著改善与提高了瓦斯煤尘混合物的爆炸特性，降低了瓦斯煤尘混合物的爆炸下限。采用图像处理的方法对煤尘爆炸产物颗粒表面的结构特性进行了半定量分析，获得了产物颗粒表面的孔隙形状因子及其分布。

Investigation on coal dust explosion characteristics using 20 L explosion sphere vessels

Using standard 20 L explosion sphere vessels，the explosion characteristics of three different coal dust and mixtures of dust and methane were investigated and the characteristic parameters of coal dust explosion were accessed and discussed.Results show that the explosion characteristic of different coal dust present significant differences.With the increasing of dust concentration，the explosion characteristic parameters presents first increase and then decrease trends in the selected dust concentration range.The flame development period of volatile gas is significantly extended with the increasing of initial pressure in the vessels，which make coal dust explosion parameters increase with the initial vessels pressure.The added methane gas significantly improve and enhance dust mixture explosion characteristics and decrease lower explosion limit of dust.By image processing technique，SEM pictures of explosion products were treated and physical structure of pores shape factor and its distributions of particle surface were analyzed.