Numerical study of the geometrical parameters on CH4/air premixed combustion in heat recirculation micro-combustor

This paper researches on premixed combustion of a methane/air mixture in a heat recuperation micro-combustor with corundum material, in terms of combustion characteristics of CH4/air in micro channel with Rh catalyst. 3D model is used with the detailed surface elementary reaction mechanism, and analyzes the influence of the baffle length, baffle angle θ, inlet temperature and inlet velocity on the methane conversion rate and heat transfer effect in heat recuperation micro-combustor with plate structure. The results show that an increase of baffle length can increase methane conversion rate and average temperature of burner, but it reduces methane conversion speed, and the maximum value of methane conversion speed is found to shift toward the entrance of reaction zone. It is obvious that θ = 2° can increase the area of high temperature distribution zone, meanwhile, the temperature distribution becomes more and more uniform, but the maximum value of temperature is lower than the others in any one inlet temperature conditions, and the value is merely 1350 K. The research indicates that the baffle angle θ of burner can significantly influence the distribution of flow velocity field, and further effect on the distribution of temperature field.