Experiments on Flame and Shock Wave Propagation in a Parallel Tunnel in Underground Coal Mines

摘要

In order to investigate the explosion propagation in a parallel runnel underground, the experiment was performed in a parallel pipe which is similar to Parallel tunnels in underground coal mine. It was found that the values of flame speed and peak overpressure (△Pmax )in two different branches of the parallel pipe were close when the ignition was started at roadway head. The explosion violence was strengthened after the flame and blast wave superimposing, and the value of △Pmax increased from 0.38 MPa to 0.46 MPa. When the ignition was started in the working face, the flame speed and peak overpressure increased slowly as the explosion propagated to adjacent roadway head. When the explosion propagated to farther closed end, the values of △Pmax kept increasing, but the flame speed acceleration was distinguished by three different parts. The peak overpressure near the meeting-point (0.44 MPa) was higher than that at the two adjacent points (0.39 MPa and 0.38 MPa) while the flame speed showed a downtrend. The violence of underground gas explosion near the meeting-point was more serious, so that the equipment and people in this area should be paid more attention.