Stabilization of an edge-flame in a corner region

The problem under consideration is concerned with the mixing and combustion of two mutually perpendicular streams, one containing fuel and the other oxidizer. Combustion occurs in the corner in the form of an edge-flame which consists of one or two premixed segments and a trailing diffusion flame. The focus in this work is on flame stabilization, onset of oscillations and/or blowoff. At low flow rates the edge-flame is always stabilized near the corner. For sufficiently small Lewis numbers the flame is blown off when the flow rate exceeds a critical value, but for Lewis numbers that are sufficiently large increasing the flow rate leads to spontaneous oscillations. The oscillations do not always persist as the flow rate continues to increase; they are often amplified leading to blowoff, or damped leading to restabilization. To better understand the phenomenon of flame restabilization we have carried out a complete stability analysis of a similar yet simpler problem, namely a flat flame on a porous-plug burner, which also exhibits a similar behavior.