Analysis of the Reaction-Advection-Diffusion Spectrum of Laminar Premixed Flames

The dynamics of one-dimensional laminar premixed combustion in reactive mixtures described by a 1) simple one-species model, 2) simple two-species model, and 3) detailed chemical kinetics model with multicomponent transport in hydrogen–air is investigated. For each model 1) spatially homogeneous results are first obtained, followed by 2) timeindependent, spatially inhomogeneous results, and ended by 3) a generalized eigenvalue analysis to calculate the spatially discretized systems’ time scale spectrum. The results reveal that for spatially resolved structures, the systems’ short wavelength modes are dominated by diffusion-based time scales, coarse wavelength modes are dominated by reactionbased time scales, and modes near a cross-over wavelength have time scales dictated by a combination of reaction and diffusion effects.