Lean premixed combustion of methane-air in a novel preheated miniature combustor with a flame holder and porous medium

Abstract

To improve the performance of the lean premixed combustion LPC that can achieve low emission of CO and NOx with high combustion efficiency, a novel preheated miniature combustor with a flame holder and porous medium is proposed here. The lean premixed combustion behaviors of methane-air are experimentally investigated in this combustor, and the corresponding thermal performances of the combustor wall are also revealed. The flashback, combustion within the porous medium, combustion next to the porous medium, and flame extinction are observed in sequence with a decreasing equivalence ratio. For the flame within the porous medium, it firmly resides within the porous medium. Therefore, in the practical application, a higher porous medium can be employed if the corresponding operating range of the LPC is sufficient. This study expands our insights into the lean premixed combustion features.