煤粉对旋转摩擦火花引燃甲烷的影响

参照GB13813搭建了旋转摩擦实验装置，研究摩擦火花引燃甲烷、空气与煤粉混合物的规律.通过高速摄像机和红外热像仪，确定A3钢和钛金属棒在连续摩擦过程中引燃甲烷与空气混合物的是摩擦撞击产生的钛金属火花，而非摩擦热接触面.分别选取三种粒径的褐煤、烟煤和无烟煤粉尘样品，测试煤粉对旋转摩擦火花引燃甲烷与空气混合物的影响规律，发现加入煤粉后甲烷空气混合物着火延迟时间较长.对于同类煤粉，粒径越小爆炸延迟时间越长.对于同一粒径的三种煤粉，着火延迟时间由长到短依次为褐煤、无烟煤、烟煤，其规律与煤粉含水量的多少一致；但未发现和煤挥发分有明显关系.

Influence of Coal Dust on the Ignition of Methane/Air Mixture by Rotating Friction Sparks

A rotating friction test device was set up based on the GB13813 to investigate the ignition regularities of methane， air and coal dust. The observation via high speed camera and infrared thermography shows that the methane/air mixture is ignited by titanium particle spark during the friction process of A3 steel and titanium bar. A set of experiments， using lignite， bituminous and anthracite with 3 kinds of particle diameters， were conducted to test the influence of coal dust on the ignition of methane/air mixture. It is found that the ignition delay time gets longer when introducing coal dust and smaller particle can cause longer delay time. The ignition delay time for the three kinds of coal from short to long is bituminous， anthracite and lignite， which accords with the water content in the sample. The delay time has nothing to do with the volatile of the coal.