Computational study the effects of venting pressure and ignition location on the fuel-air mixture explosion load in vented chamber

Abstract

Numerical analysis were performed to study venting explosion load of methane-air in vented chamber. The effects of venting pressure and ignition location on indoor gas explosion overpressure are discussed. The simulation results showed the expected trends are agreed with the experiments in some extent. Several peaks in overpressure were identified along the pressure–time curves. There are two typical peak overpressures in our study. The first peak is due to the vent failure. The second is caused by the external explosion. It’s not a monotonic relationship between the peak overpressure and venting explosion pressure. The influence of the venting pressure on the explosion overpressure is irregular when the venting pressure is less than 10 kPa. Then the explosion overpressure increases with the increase of the venting pressure. The results show that, the maximum peak value of overpressure is shear ignition. But the local overpressure on the pressure relief wall is stronger due to turbulence in central ignition case. Explosion venting process couples the turbulent flow and chemical reaction of combustible medium which is influenced by several parameters.