Numerical study on lateral movements of cellular flames

Abstract

The lateral movements of cellular premixed flames for the Lewis number unity or smaller are studied by means of numerical simulation. The numerical model includes compressibility, viscosity, heat conduction, molecular diffusion, body force, chemical reaction, and convection. We superimpose the disturbances with peculiar wavelengths on the plane flames and calculate the evolution of disturbed flames. When the hydrodynamic and body-force instabilities are dominant (the Lewis number is unity), stationary cellular flames are formed. When the diffusive-thermal instability has a great influence (the Lewis number is smaller than unity), laterally moving cellular flames are obtained. The numerical simulation shows that the Lewis number effect and the nonlinear effect of the flame front are the essential factors in the lateral movements of cellular flames.