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.