A Physics Based Approach to Modeling Grassland Fires

Published

January 30, 2007

Author(s)

William E. Mell, M A. Jenkins, J Gould, P Cheney

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 orempirical. However, there are a number of fire 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 severity of wildland fires, and investigating the mechanisms andconditions underlying blow-up fires. These problems are not amenable to repeatable full scale field studies. Suitablyvalidated 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 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 lengthscompared favorably 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.

Citation

International Journal of Wildland Fire

Volume

16

Pub Type

Journals

Download Paper

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Keywords

CFD, fire spread, pyrolysis, wildfire

Citation

Mell, W. , Jenkins, M. , Gould, J. and Cheney, P. (2007), A Physics Based Approach to Modeling Grassland Fires, International Journal of Wildland Fire, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=861373 (Accessed April 26, 2024)