Influence of Radiative Heating on Wildfire Behavior—A Sensitivity Study

Wildfire behavior is driven by a number of physical factors, including topography, local atmospheric winds, temperature, and humidity, fuel loading, and radiative heating of the surrounding fuel. Our aim is to study the complex interactions of these forcings on the propagation of a wildfire in a series of sensitivity runs, with special attention given to the relative importance of radiative heating on the wildfire behavior.

We use the HIGRAD/FIRETEC CFD model to conduct these sensitivity runs. The model is a physics-based coupled-atmosphere/wildfire model that combines the atmospheric modeling capability of the LANL HIGRAD CFD code with the FIRTEC wildfire code. This package also includes a three dimensional diffusion-based radiation package to simulation the radiative heating due to a wildfire. The base simulation is modeled after a portion of the Calabasas fire that occurred in the Santa Monica Mountains in Los Angeles County in October, 1997.