Energy dissipation law and safety sizes of hole in outburst prevention door for passing outburst shock wave

In order to reveal the law of energy dissipation when the outburst shock wave passes through the hole in the anti-surge door, the sill of the anti-surge door was taken as the research object. The propagation law of the outburst shock wave in the roadway and when it crosses the bottom sill of the outburst prevention door was analyzed based on the physical test and numerical simulation of coal and gas outburst under the conditions of different outburst pressures and bottom sill sizes of the outburst prevention door. According to the relationship between the overpressure of the outburst shock wave and the ventilation resistance of the roadway, as well as the damage criterion of the overpressure of the outburst shock wave to the human body, the size of the bottom sill of the outburst prevention door was determined. The research results show that ① the outburst shock wave passing through the intersection of the roadway mainly propagates in the straight roadway. The shock wave propagation velocity and overpressure are positively correlated with the outburst pressure. ② The main reason for the increase in shock wave overpressure near the front of the outburst prevention door is the superposition of the incident shock wave and the reflected shock wave after hitting the outburst prevention door. The superimposed shock wave overpressure and reflected shock wave overpressure increase with the decrease of the bottom sill size of outburst prevention door. ③ The smaller the size of the bottom sill of the outburst prevention door is, the stronger the shock wave is blocked by the outburst prevention door's bottom sill, and the more difficult it continues to propagate forward for the incident shock wave to bypass the bottom sill of outburst prevention door. ④ When the branch roadway is close to the outburst prevention door, the corresponding backflow prevention device should be installed in the branch roadway. ⑤ When the bottom sill size of the outburst prevention door is less than 15 mm, the shock wave after passing through the bottom sills of two wind door will not cause gas backflow, and the overpressure of the shock wave after passing through the bottom sill of two wind door will not cause harm to the human body. Therefore, it is reasonable to set the safety size of the bottom sill of mine outburst prevention door to 15 mm or less. ⑥ The results of theoretical analysis, physical test and numerical simulation are basically the same, indicating that the analysis results in this paper are reliable.