Exploring the effect of inflow turbulence in coupled atmosphere-fire simulations using innovative subgrid fire front reconstruction
Résumé
This paper introduces the Blaze fire model based on a Eulerian level-set front-tracking method
and solved using high-order numerical schemes. Blaze includes an original and efficient subgridscale
burning area reconstruction to substantially reduce computational cost. Blaze can run at a
resolution that is ten times coarser than that of similar models like SFIRE for the same accuracy.
In this study, Blaze is coupled to the MesoNH atmospheric model to evaluate its performance
against the FireFlux I experimental data set. Results show good agreement between simulations
and measurements for both 25-m and 10-m atmospheric resolutions combined with a 5-m fire
resolution. A more realistic air temperature near the ground is obtained by considering heat
fluxes in the already burnt area and not only at the flaming front. Also, the significant impact
of inflow turbulence on both fire spread and fire-induced atmospheric flow is highlighted. This
study motivates the use of simulation ensembles rather than a single deterministic simulation to
account for environmental variability at the scale of a prescribed burn such as FireFlux I.