Simulation of forest fire spread using a two-way coupling algorithm and its application to a real wildfire

Abstract

The incident wind velocity in a forest fire is one of the main factors affecting fire spread. Although buoyancy due to the fire heat release modifies the wind field, the standard procedure for fire simulation takes the undisturbed wind field, computed in the absence of the fire thermal effects. The present work addresses this problem, by using a method to take into account the mutual interaction (two-way coupling) between fire and wind. This study is based on the FireStation system, a software package that combines a semi-empirical fire spread model with a Navier-Stokes solver for wind calculation, using a dynamic interchange between the fire spread model and the wind model. The present work describes the application of this model to a real wildfire case, the two-way coupling approach proving to be a better option, with predictions of fire size and shape in closer agreement with the observed ones.