Consequence of bluff body in lean, premixed micro-combustion of methane-air mixture.

The chemical reaction between a fuel and an oxidizer at micro level, exothermic in nature, is known as micro-combustion is studied, as well as the flame stability and characteristics of combustion of a lean and premixed methane and air combination in a micro combustor with different heat production and chemical species conversion. Shapes of bluff bodies (half ellipse, crescent, wall-blade, and triangle) under different physical and chemical conditions are examined by solving governing equations in two dimensions. For intake mixture velocities of 10 m/s and 20 m/s and 0.59 equivalence ratio, blow-off limit of various bluff bodies, emitter efficiency, effect on flame structure and exhaust gas temperature of micro-combustor are investigated. The micro-combustor is made out of steel with 20 W/m.K conductivity. Existing literature suggests that geometry of wall blade produces the highest flame temperature for non-hydrocarbon - air mixtures. [ABSTRACT FROM AUTHOR]