Numerical simulation on the effect of inclination on rectangular buoyancy-driven, turbulent diffusion flame

Abstract

The presence of an inclined wall can significantly alter the flow dynamics of a buoyancy-driven turbulent flame. Although flame structure on an inclined wall has been widely investigated, fluid flow has not. A large eddy simulation is performed to study the effect of inclination on the flow dynamics of a flame. Results show that, at the initial stage of combustion, a vortex forms at the left side of the flame due to its expansion and the adverse pressure gradient downward. The vortex expands and lifts with the combustion flow, splitting the flame by stretching its left edge. During the continuous combustion stage, the flame is inclined on the inclined wall. Air entrainment on the left side of the flame flows parallel to the inclined wall, while air entrainment on the right side is significantly reduced due to the upward movement of the combustion flow. The flame inclination angle increases with increasing inclination angle and attaches the inclined wall when the inclination angle is 30{degree sign}, leading to a higher mean temperature and velocity near the inclined wall.