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arXiv · 2110.03364

A general model for wildfire propagation with wind and slope

Miguel Ángel Javaloyes·Enrique Pendás-Recondo·Miguel Sánchez
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Abstract

A geometric model for the computation of the firefront of a forest wildfire which takes into account several effects (possibly time-dependent wind, anisotropies and slope of the ground) is introduced. It relies on a general theoretical framework, which reduces the hyperbolic PDE system of any wave to an ODE in a Lorentz-Finsler framework. The wind induces a sort of double semi-elliptical fire growth, while the influence of the slope is modeled by means of a term which comes from the Matsumoto metric (i.e., the standard non-reversible Finsler metric that measures the time when going up and down a hill). These contributions make a significant difference from previous models because, now, the infinitesimal wavefronts are not restricted to be elliptical. Even though this is a technical complication, the wavefronts remain computable in real time. Some simulations of evolution are shown, paying special attention to possible crossovers of the fire.

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Miguel Ángel Javaloyes, Enrique Pendás-Recondo, Miguel Sánchez. 2021-10-07. A general model for wildfire propagation with wind and slope. https://doi.org/10.1137/22m1477866

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