Research on the effects of coal dust parameters on the venting characteristics of gas/dust two-phase explosions

Based on the correlation analysis of venting flame propagation and pressure rise both sides of vessel, the dynamics venting characteristics of gas/dust explosions and influence of dust parameters were studied. Venting parameter appeared a variation process of firstly rising and then reducing with increasing coal dust concentration (q). As q=300 g/m3, venting parameters were the greatest. But it was gradually increased as dust diameter reduced. Venting flame could be affected by dust parameters. As the flame extinguished, an evident oscillation phenomenon emerged and its oscillation amplitude change was similar to venting parameter. A secondary venting flame appeared after extinguishing and got more dramatically with increasing dust diameter. Besides, the pressure at the venting port exhibited an obvious negative value and its appearance moment was corresponding to flame oscillation. And the temperature contour showed the same morphology as flame image. Temperature distribution was related to explosion intensity and affected by dust parameters.