Dynamics of Ignition and Extinction Fronts on Diffusion Flame Sheets

Northwestern University, Evanston IL

Investigators

Abstract

This is a study of the propagation of ignition and extinction fronts (edge flames) on diffusion-flame sheets using a combination of analytical methods and numerical simulations. The scope and utility of the previously articulated parabolic flame path assumption (PFPA) and its incorporation into the activation-energy asymptotics framework are tested. Systems examined include extinction fronts, colliding triple flames, and circular ignition fronts. The work has implications for describing a member of important practical phenomena including lift-off and blow-out of jet flames, autoignition in diesel engines, flame spread over fuel beds, and local extinction in turbulent nonpremixed combustion.