Radiation Effects on the Flame Structure and Extinction Limit of Counterflow Partially Premixed Methane Flames Diluted with Water Vapor in the Air Stream

공기류측에 수증기가 첨가된 대향류 메탄 부분예혼합화염의 화염구조 및 소화한계에 미치는 복사효과

Radiation effects on the partially premixed methane flames diluted with water vapor in the air stream were numerically investigated. OPPDIF code and GRI-v3.0 were used in the numerical simulation. Adiabatic condition was compared with two different radiation models, optically-thin and WSGGM models. It was found that the radiation effect on the flame structure for the equivalence ratio (${\Phi}$) of 2.5 was less than ${\Phi}=1.5$. Extinction limit was not affected significantly, however, local flame structure was markedly influenced by the radiation models as increasing the water vapor concentration.