Substantiating a fractal-based algebraic reaction closure of premixed turbulent combustion for high pressure and the Lewis number effects

A comprehensive set of nearly 100 atmospheric and high-pressure flame data of Kobayashi et al. are a good source for numerical analysis to address two main aspects in premixed turbulent combustion—high-pressure influence and effects of fuel type on the reaction rate. The present work deals with the lucid and realizable fractal-based reaction rate closure from Lindstedt and Váos (LV model) for premixed flames in the thin-flame limit. In this study, the reaction source term is customized on the eddy viscosity closure of turbulent transport, for practical reasons. Computed results from the LV model show the right qualitative trends with the experimental findings, as a function of turbulence. However, quantitative predictions of the original model are partly too low, and preclude the effects of pressure and fuel type on the reaction rate. With an extensive parametric study, based on numerical findings as well as on theoretical argumentation, the LV model is substantiated for these two effects. Results from the proposed tuned LV model are found to be in very good agreement with most of the measured data.