Experimental and numerical study on pressure dynamic and venting characteristic of methane-air explosion in the tube with effect of methane concentration and vent burst pressure

• The internal pressure curves all present two typical pressure peaks. • The methane concentration and P V have the effect on the venting flow velocity. • The pressure oscillation is noticed in the internal pressure curves when methane concentration is from 9 vol% to 13 vol%. • The internal temperature curves, the change of methane concentration and venting flow velocities are analyzed. This paper presents the experiments and numerical simulation of vented methane-air explosion. The influence of methane concentration and vent burst pressure on the internal pressure dynamic and venting characteristic is investigated. The pressure oscillation is hardly noticed in the internal pressure curve as the case of concentration is 7 vol%. But for the case of concentration is from 9 vol% to 13 vol%, the pressure oscillation is obvious in the internal pressure curves. Two internal temperature peaks are found in the three simulated temperature curves. The duration of internal temperature curve will increase with the increase of methane concentration. The methane concentration and vent burst pressure have the influence on the variation curve of the internal fuel concentration. When the methane concentration is 7 vol%, it is worth noting that the internal fuel concentration drops rapidly to zero after vent opening. And when the methane concentration is 9 vol% or 11 vol%, the internal fuel concentration has a dramatic decrease and then maintains a slow descent after vent opening. The internal pressure curves with different concentrations all present two typical pressure peaks. The first pressure peak is more noteworthy than anther one under higher vent burst pressure conditions; the second pressure peak is more important under lower vent burst pressure conditions.