Experimental Study on Explosion of Premixed Methane-air with Different Porosity and Distance from Ignition Position

Abstract

ABSTRACT In order to suppress the overpressure and flame damage caused by the explosion of premixed methane-air, a self-built duct with a 10 × 10 × 100 cm was used to conduct an experimental study on the explosive characteristics and propagation rules of 9.5% methane under the effect of different porous materials at a fixed position. The methods of suppressing methane-air explosion in confined space are optimized. By analyzing the effect of porosity and distance of the porous material on the explosion, the overpressure and flame propagation characteristics after the methane-air explosion and under the influence of the dual factors are studied. It provides data support to explain the mechanism of blocking and suppressing premixed methane-air explosion when porous materials with different porosity and different positions. Studies have shown that the different porosity of porous materials and the position from the explosion source have significant and different effects on the propagation of overpressure and flame. The 10 PPI porous material has a strong promoting effect on the overpressure and flame propagation after the explosion, it accelerates the overpressure rising rate and increases the overpressure peak, and enhances the turbulence intensity of the explosion flame and accelerates the flame propagation rate. The 20 PPI porous material failed to suppress the explosion during the acceleration phase, but had certain suppression on the explosion flame in other phases. The effect of 30 PPI porous material to suppress explosion overpressure and flame depends on where it is placed. Both 20 PPI and 30 PPI porous materials can quench the flame and block the propagation of high-temperature carbonaceous products. This research results have theoretical value and guiding significance for the prevention and emergency treatment of methane explosion accidents.