- Author
- Mell, W. E. | Jenkins, M. A. | Gould, J. | Cheney, P.
- Title
- Physics-Based Approach to Modeling Grassland Fires.
- Coporate
- National Institute of Standards and Technology, Gaithersburg, MD York University, Toronto, ON M3J 1P3, Canada Commonwealth Scientific and Industrial Research Organization, Melbourne, Australia Bushfire Cooperative Research Centre, East Melbourne, Vic. 3002, Australia
- Journal
- International Journal of Wildland Fire, Vol. 16, No. 1, 1-22, 2007
- Sponsor
- Department of Agriculture, Washington, DC
- Keywords
- grasslands | wildland fires | computational fluid dynamics | fire spread | fire models | equations | combustion | topography | solid fuels | thermophysical properties | simulation | experiments | fire behavior | heat release rate | wind effects | mass flus | wind velocity | fuels beds | computer simulation | surface fuels | ignition
- Identifiers
- physics-based wildland fire models; grassland fire expedriments; effect of wind on head fire spread; effect of fire head width on fire spread; residence time, mass flux and heat release rate; Wildland/Urban Interface (WUI) fires
- Abstract
- Physics-based coupled fire-atmosphere models are based on approximations to the governing equations of fluid dynamics, combustion, and the thermal degradation of solid fuel. They require significantly more computational resources than the most commonly used fire spread models, which are semi-empirical or empirical. However, there are a number of fire behaviour problems, of increasing relevance, that are outside the scope of empirical and semi-empirical models. Examples are wildland-urban interface fires, assessing how well fuel treatments work to reduce the intensity of wildland fires, and investigating the mechanisms and conditions underlying blow-up fires and fire spread through heterogeneous fuels. These problems are not amenable to repeatable full-scale field studies. Suitably validated coupled atmosphere-fire models are one way to address these problems. This paper describes the development of a three-dimensional, fully transient, physics-based computer simulation approach for modelling fire spread through surface fuels. Grassland fires were simulated and compared to findings from Australian experiments. Predictions of the head fire spread rate for a range of ambient wind speeds and ignition line-fire lengths compared favourably to experiments. In addition, two specific experimental cases were simulated in order to evaluate how well the model predicts the development of the entire fire perimeter.