Effect of variable heat loss intensities on the dynamics of a premixed flame

The general character of the equation concerning premixed flame fronts in nonuniform and unsteady flows, which was developed by Clavin and Williams (1982) and Clavin and Joulin (1983), is questioned. In the Clavin et al. treatment, the effects of the front curvature and flow inhomogeneities appear through only one geometric scalar expressing the nondimensional flame stretch experienced by the curved fronts. In the present analysis, which examines the effects of volumetric heat losses in the presence of temperature-dependent diffusivities, it is shown that the contribution of the flame-front curvature is different from the contribution of flow inhomogeneities. It is argued that from the quantitative point of view the validity of the Clavin equation is limited. (I.S.)