甲烷-煤尘复合爆炸威力实验

Experiment on methane-coal dust explosions

建立了由压力变送器、数据采集卡、计算机和电极点火装置组成的密闭空间甲烷-煤尘复合爆炸实验系统,动态响应时间小于1 ms,测试精度为0.5级.对甲烷-煤尘复合爆炸威力进行了系统的实验研究.结果表明:密闭空间内甲烷-煤尘复合爆炸的最危险爆炸条件为甲烷浓度5%,煤尘浓度500 g/m3,煤尘粒径26μm,点火延迟时间40 ms;最大爆炸压力与甲烷浓度、煤尘浓度和点火延迟时间呈二次函数关系;最大爆炸压力随着煤尘粒径的增大而减小.甲烷的存在使得纯煤尘在空气中的爆炸下限降低,而爆炸压力增大;同样,煤尘的存在使得甲烷的爆炸下限降低,而爆炸压力升高.

An experimental system including pressure transducer, data acquisition card, computer and electric spark ignition device was set up to experimentally study methane-coal dust compound explosions in confined vessels. Its dynamic response time was less than a millisecond and test precision was 0.5%. The experimental results show that the maximum explosion pressure is quadratic with methane concentration, coal dust concentration and ignition delay time and increases with coal dust size. The most dangerous condition is that the methane concentration is about 5%, the coal dust concentration is about 500 g/m^3 , and the ignition delay is about 40 ms. Methane reduces the explosion low limit but increases the explosion pressures of coal dust. Also, coal dust reduces the explosion low limit but increases the explosion pressure of methane.