ABSTRACT

To study the explosion characteristics of coal dust samples with different metamorphism, 19 coal samples including anthracite, bituminous coal, lignite were selected, explosion pressure distribution and flame propagation velocity were studied in an explosion pipeline with an outer diameter of 108 mm and an inner diameter of 88 mm. Coal dust particles were injected into the pipeline by eight dust nozzles controlled by solenoid valves. The explosion pressure and flame propagation profiles were obtained by PCB piezoelectric sensors and photoelectric sensors. The experimental results suggested that the explosion pressure profiles of different coal samples are all present a first increasing and then decreasing trend. However, there is a drop point at 0.875 m from the ignition end. The flame propagation velocity increases first and reaches the maximum at 0.625 m from the ignition end, and then the propagation velocity begins to decrease until the end of the pipeline, while there exist a slight enhancement at 1.105 m from the ignition end. Furthermore, the coal samples with different coal ranks have different explosion severity, coal samples with lower moisture content, and relatively higher volatile matter present a better deflagration property and cause a higher explosion severity.

摘要

为研究不同变质煤尘样品的爆炸特性，选取无烟煤、烟煤、褐煤等19个煤样，在外径108 mm、内径为108 mm的爆炸管道中研究爆炸压力分布和火焰传播速度。 88 毫米。煤尘颗粒通过电磁阀控制的八个粉尘喷嘴喷入管道。爆炸压力和火焰传播曲线由PCB压电传感器和光电传感器获得。实验结果表明，不同煤样的爆炸压力分布均呈现先增大后减小的趋势。但是，在距点火端 0.875 m 处有一个下降点。火焰传播速度先增大，在距点火端 0.625 m 处达到最大值，然后传播速度开始减小，直至管道末端，而在距点火端 1.105 m 处略有增强。此外，不同煤级的煤样具有不同的爆炸烈度，含水量较低、挥发分相对较高的煤样具有较好的爆燃性，引起较高的爆炸烈度。