Effect of dimethyl ether blending on methane flame morphology transformation and stabilization mechanism in a micro-planar combustor

Abstract

This paper presented a novel blended combustion solution for mixing methane/dimethyl ether/air in a micro combustion chamber. Simulations were used to compare the pure methane combustion with the blended combustion, focusing on the OH species distribution, y-axis velocity, and strain rate to reveal the flame dynamics differences in different combustion conditions. The results showed that the blowout limit was enhanced from 0.53 m/s to 1.18 m/s at a blending ratio of 50 %. The blending of DME was also beneficial in weakening the flame asymmetry, delaying the generation of inclined flames in the original combustion, and replacing the inclined flames by a double-peaked U-shaped flame and an inverted U-shaped flame at an equivalence ratio of 0.9. Overall, this study not only provides a reliable fuel mixture for enhancing the combustion process under microscale conditions, but also reveals the flame transition characteristics.