The effects of porous wall as a novel flame stabilization method on flame characteristics in a premixed burner for CH4/air mixture by numerical simulation

Abstract

In the present investigation, the effects of inner diameter and length of porous wall on flame stability limits, temperature distribution, methane conversion, and pressure drop in a premixed burner are numerically analyzed. The governing equations are solved by the control volume method, considering Re-Normalization Group k-ɛ for turbulence modeling and eddy dissipation concept for turbulence–chemistry interaction modeling. The simulations are performed for various porous walls with the inner diameter of 30, 40, and 50 mm and the length of 22, 44, and 66 mm. The results demonstrate that the increase in inner diameter of porous wall causes an increase in the lower flame stability limit and a decrease in the upper flame stability limit, gas and solid temperatures, pressure drop, and methane conversion. Also, the maximum solid and gas temperatures in the porous wall and methane conversion are related to the porous wall with 44 mm length. Furthermore, the methane conversion and pressure drop increase with the rise in the equivalence ratio. Finally, it can be said that the change in inner diameter of porous wall is more important than the length of porous wall in the studied phenomena.