Effect of Radiation Reabsorption on Laminar Burning Velocity of Methane Premixed Flame Containing with Steam and Carbon Dioxide

Abstract

Flame properties in the ambience of steam and carbon dioxide are complicated because of the third-body effect and radiation reabsorption. Thus, we performed detailed chemical kinetic calculations that include the effect of radiation reabsorption to clarify the premixed laminar flame speed of such a mixture, being one of the most important properties for controlling combustion. Pressure was varied up to 5.0MPa to simulate the 1700°C class combined gas turbine system. The results show a marked increase in laminar burning velocity by considering radiation reabsorption. Laminar burning velocity was increased up to 150% in cases of methane-oxygen and steam or carbon dioxide mixtures. It was found that the preheating of the upstream, unburned mixture caused this increase. The influence of radiation reabsorption was much larger in the case of lower pressures.