Effects of Flame Temperature and Absorption Coefficient on Premixed Flame Interactions with Radiation

Abstract

The effects of the flame temperature and the absorption coefficient on interactions between radiative heat transfer and the flame behavior were numerically investigated using high-fidelity numerical code with the discrete ordinates method. To study the effects of the flame temperature and the absorption coefficient, three different flame temperatures and four different absorption coefficient conditions were selected, so twelve test cases were studied in total. In the numerical test results, radiation effects resulted in preheating of the reactant gases and heat loss from the product gases. A higher flame temperature resulted in stronger preheating effects in reactants near the flame. Due to the preheating effects, with the appropriate absorption coefficient, the peak temperature appeared at the flame front. Lower flame temperatures resulted in larger reabsorption effects in the product zone. The peak temperature at the flame front and the flame speed were influenced by the combined effects of preheating and radiative heat loss at the flame front. Depending on the conditions, due to those effects, the peak temperature and the flame speed could increase or decrease. When the absorption coefficient was sufficiently large, the temperature decrease was reduced in the product zone.