Effect of radiation on the solutions of SANDIA Flame D with the flamelet model

Radiation plays an important role on some combustion processes. Heat transfer mechanism is strongly affected from radiation. This is an important mechanism that affects the characteristics of the flame. Additionally, turbulence is another important issue for consideration. Therefore, turbulence and radiation have to be considered carefully for combustion simulations. This paper presents a study on the effect of radiation for the simulation of a turbulent, non-premixed methane-air flame by using the flamelet model. GRI-Mech 3.0 was used for chemical reaction mechanism and turbulence was considered by using the steady laminar flamelet model coupled with PDF methods. To understand the effect of radiation very clearly, two situations was compared to each other. On of these simulations was carried out without radiation and another one was carried out with radiation. Results of the study shows that maximum temperature difference between the flames is equal to 34 K. This difference is reached at r/d equals to 80. Maximum flame temperatures for the without radiation and radiation model are equal to 1986 K and 1969 K, respectively. Maximum temperature is predicted more precisely by using the radiation model. Generally, there is no big difference between the two flames in terms of the temperature. Consequently, radiation can be ignored for these types of study.