Forest Fire SimulationMathematical Models and Numerical Methods

Resumen

At present, there exists a wide range of fire behavior models and studies aiming to simulate fire. After a brief review of fire spread models we focus on physical models. Physical or combustion models describe the evolution of physical quantities inside the vegetation, considered as a porous medium, and as a consequence provide the evolution of the fire front. Between combustion models we can distinguish two groups: 1. Complex models, where general conservation laws are considered and several phases, solid phase and gas phase with different temperatures, two layers models, etc. 2. Simplified models, where in general an average media is considered with average magnitudes. Usually only one temperature is considered and only one phase (the other phase is parameterized). The simplified models are more realistic than models based on cellular automata, geometric models and other empirical models, but allow faster computations than complex models, providing computation times below real time and at the same time taking into account the main physical mechanisms concerning the fire propagation. This models takes into account three of the main mechanisms in fire spread, namely, Water content, Radiation qndWind and topography effects. We will discuss also some aspects concerning the numerical methods involved.