FLAME STABILIZATION STUDIES IN A THREE BACKWARD FACING STEP CONFIGURATION BASED MICRO-COMBUSTOR WITH PREHIXED METHANE-AIR MIXTURES

摘要

In the present work, experimental investigations on the characterization of flame stabilization behavior in a 2.0 mm base diameter with three backward facing steps and premixed methane-air mixture has been reported. Maximum and minimum diameter in the micro-combustor was kept constant at 2mm and 6mm respectively. Parametric investigations are carried out to understand the effect of change in length of the steps, number of steps, mixture equivalence ratio ((Φ) and flow rate on flame stability limit and wall temperature profiles. It was observed that the recirculation zone created due to sudden expansion at the backward step helps in stabilizing the flame within the micro-combustor and enhances the flame stability limits significantly. The increase in the length of the first and second step helps in enhancing the flame stability limits at both lower and higher flow rates. The increase in the length of the third step affects the flame stability limit at higher flow rates only.