Analysis of the Impact of Lateral Conduit and Metal Wire Mesh on Methane Explosions

Abstract

To enhance the deflagration efficiency and protection level of combustible mixed gases in narrow spaces, a small square experimental pipeline system was designed. Experiments were conducted to investigate the effects of lateral vent pipes and metal wire meshes on the explosion characteristics of methane gas. This study examined the influence of changing the positions of the lateral vent pipes and metal wire meshes in the pipeline on the variation of parameters such as the flame shape, leading speed, and pressure of the methane/air premixed gas in the pipeline. The results indicated that the lateral vent pipes could effectively release part of the energy from the methane explosion, and the release effect was stronger the closer they were to the ignition end. This was significantly more effective in releasing the flame and pressure than when the vent pipes were placed in the middle or at the end of the pipeline. For lateral vent pipes close to the ignition source, their effective release of the not yet fully developed premixed flame allowed the heat absorption, wave absorption, and quenching performance of the installed metal wire mesh in the pipeline to fully exert their effects on the slow-spreading premixed flame. Furthermore, when a metal mesh was installed in the pipeline and the flame could not be extinguished, the flame penetrated the mesh structure, causing the flame front to become unstable and exhibit “irregular wrinkles”. That is, the flame front was no longer smooth, the wrinkles became more pronounced, and the degree of turbulence was enhanced.