This study investigates how to enhance the wall temperature and uniform distribution of temperature at the microcombustor wall using oxy-methane combustion. Power generation via oxy-combustion provides oxygen to the combustion process by separating oxygen from the air. Ansys Fluent 14 software solves/iterates the problem by importing the file, which GAMBIT exported to define the problem in Fluent. This present study used the modified reaction mechanism of the 4-step Jones Lindstedt (JL) mechanism and the 2-step Westbrook- Dryer (WD) mechanism. Various boundary conditions were set, and the combustor modelled to discharge to the surroundings on atmospheric conditions. The numerical scheme was validated with existing experimental data from previous literature. The highest difference in exhaust gas temperature was 7.46% at 11.17 m/s velocity inlet of the microcombustor. It was noted that the temperature at lower power density (LPD) is higher than that at higher power density (HPD). The reason is that the impact of temperature in the microcombustor is weak at HPD. The level of combustion reactions is gradually enhanced with the amassed oxidiser PD, leading to a rise in the utmost mole fraction of Carbon monoxide. The results show that the increase in outer wall thickness enhances the heat transfer in the microcombustor. In addition, the temperature of outer wall and consistency are enriched as the equivalence ratio increases. High wall temperature is attained when the equivalence ratio is 1.0, while the uniformity of temperature is optimal at the equivalence ratio 0.8 and a power density of 30W for Oxy-methane combustion.
Key words: Equivalence ratio, Exhaust temperature, Oxy-methane combustion, Micro combustor, WD-oxy
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