The linear-Eddy model

Abstract

Regime-independent modeling is important for accurate simulation of the complex combustor designs needed to meet increasingly stringent performance requirements. One strategy for achieving robust yet affordable predictive capability is to resolve, in space and time, the relevant advection-diffusion-reaction couplings using a low-dimensional representation of turbulent advection. In the linear-eddy model (LEM), this is accomplished in one spatial dimension by introducing an instantaneous map, the 'triplet map,' that emulates the effect of an eddy turnover on property profiles along a notional line of sight. The map preserves the continuity of these profiles and obeys applicable conservation laws. Details and representative applications of the model are presented for passive and reactive scalar mixing, with emphasis on its use as a mixing-reaction closure for large-eddy simulation (LES) based on the embedding of an LEM domain in each LES control volume. © Springer Science+Business Media B.V. 2011.