SPHERICALLY EXPANDING FLAMES.

A theoretical study of outwardly expanding flames originating from a point ignition source is presented. Spherically symmetric solutions are discussed and tested for stability. Flames which are stable to thermo-diffusive effects are found to become unstable after reaching a critical size. This instability which is hydrodynamic in nature is a result of the interaction of the flame with the hydrodynamic disturbances that it generates via thermal expansion. In this study, we present a linear stability analysis and determine the dependence of the critical radius on the relevant physicochemical parameters.