International Journal of Wildland Fire International Journal of Wildland Fire Society
Journal of the International Association of Wildland Fire

A physics-based approach to modelling grassland fires

William Mell A E , Mary Ann Jenkins B , Jim Gould C D and Phil Cheney C

A Building and Fire Research Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899-8663, USA.

B Department of Earth and Space Science and Engineering, York University, Toronto, ON M3J 1P3, Canada.

C Ensis-Forest Biosecurity and Protection, CSIRO, Kingston, ACT 2604, Australia.

D Bushfire Cooperative Research Centre, East Melbourne, Vic. 3002, Australia.

E Corresponding author. Email:

International Journal of Wildland Fire 16(1) 1-22
Published: 20 February 2007


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.

Additional keywords: computational fluid dynamics, fire spread, numerical simulation, wildland fire.


Albini FA (1976) Estimating wildfire behavior and effects. USDA Forest Service, Intermountain Forest and Range Experiment Station General Technical Report INT-30. (Ogden, UT)

Albini FA1985A model for fire spread in wildland fuels by radiation.Combustion Science and Technology42229258

Albini FA (1993) Dynamics and modeling of vegetation fires: observations. In ‘Fire in the Environment: The Ecological, Atmospheric, and Climatic Importance of Vegetation Fires’. (Eds PJ Crutzen, JG Goldammer) pp. 39–52. (John Wiley and Sons: Chichester)

Anderson HE (1969) Heat transfer and fire spread. USDA Forest Service, Intermountain Forest and Range Experiment Station General Technical Report INT-69. (Ogden, UT)

Andrews PL (1986) BEHAVE: Fire behavior prediction and modeling system – BURN subsystem part 1. USDA Forest Service, Intermountain Forest and Range Experiment Station General Technical Report INT-194. (Ogden, UT)

Andrews PL, Bevins CD, Seli RC (2003) BehavePlus fire modeling system, version 2.0: User’s Guide. USDA Forest Service, Rocky Mountain Research Station General Technical Report RMRS-GTR-106WWW. (Ogden, UT)

Bankston CPZinn BTBrowner RFPowell EA1981Aspects of the mechanisms of smoke generation by burning materials.Combustion and Flame41273292

Beer T1991The interaction of wind and fire.Boundary-Layer Meteorology54287308doi:10.1007/BF00183958

Chandler C, Cheney P, Thomas L, Trabaud P, Williams D (1983) Chemistry and physics of ignition and combustion. In ‘Fire in Forestry’. pp. 1–30. (John Wiley & Sons: New York)

Cheney NPGould JS1995Fire growth in grassland fuels.International Journal of Wildland Fire5237247doi:10.1071/WF9950237

Cheney NPGould JSCatchpole WR1993The influence of fuel, weather and fire shape variables on fire spread in grasslands.International Journal of Wildland Fire33144doi:10.1071/WF9930031

Cheney NPGould JSCatchpole WR1998Prediction of fire spread in grasslands.International Journal of Wildland Fire8113doi:10.1071/WF9980001

Clark TLJenkins MACoen JPackham D1996A coupled atmospheric-fire model: Convective feedback on fire-line dynamics.Journal of Applied Meteorology35875901doi:10.1175/1520-0450(1996)035<0875:ACAMCF>2.0.CO;2

Clark TLGriffths MReeder MJLatham D2003Numerical simulations of grassland fire in the Northern Territory, Australia: A new subgrid-scale fire parameterization.Journal of Geophysical Research1084589doi:10.1029/2002JD003340

Clark TLCoen JLLatham D2004Description of a coupled atmosphere-fire model.International Journal of Wildland Fire134963doi:10.1071/WF03043

Coen J (2003) Simulation of wildfire incidents using coupled atmosphere–fire modeling. In ‘Second International Wildland Fire Ecology and Fire Management Congress and Fifth Symposium of Fire on Forest Meteorology’. Paper J2.4. (American Meteorological Society) Available at [Verified 18 October 2006]

Coen J2005Simulation of the Big Elk Fire using coupled atmosphere-fire modeling.International Journal of Wildland Fire144959doi:10.1071/WF04047

Colman JJ, Linn RR (2003) Non-local chemistry implementation in HIGRAD/FIRETEC. In ‘5th Symposium on Fire and Forest Meteorology’. Available at [Verified 18 October 2006]

Colman JJ, Linn RR (2005) Separating combustion from pyrolysis in HIGRAD/FIRETEC. In ‘6th Symposium on Fire and Forest Meteorology’. Available at [Verified 18 October 2006]

Costa AMPereira JCFSiqueira M1995Numerical prediction of fire spread over vegetation in arbitrary 3D terrain.Fire and Materials19265273doi:10.1002/FAM.810190605

Davis KP (1959) ‘Forest Fire: Control and Use.’ (McGraw-Hill: New York)

De Mestre NJCatchpole EAAnderson DHRothermel RC1989Uniform propagation of a planar fire front without wind.Combustion Science and Technology65231244

Dupuy JLMorvan D2005Numerical study of the a crown fire spreading toward a fuel break using a multiphase physical model.International Journal of Wildland Fire14141151

Finney MA (1998) FARSITE: Fire area simulator-model, development and evaluation. USDA Forest Service, Rocky Mountain Research Station Research Paper RMRS-RP-4. (Ogden, UT)

Fons WL1946Analysis of fire spread in light forest fuels.Journal of Agricultural Research7293121

Forney GP, McGrattan KB (2004) User’s guide for smokeview version 4: A tool for visualizing fire dynamics simulation data. Technical Report NISTIR, Special Publication 1017. (National Institute of Standards and Technology: Gaithersburg, MD) Available at [Verified 18 December 2006]

GAO (1999) Western national forests: A cohesive strategy is needed to address catastrophic wildfire threats. Technical Report GAO/RCED-99-65. (United States General Accounting Office: Washington, DC)

GAO (2005) Technology assessment: protecting structures and improving communications during wild-land fires. Technical Report GAO-05-380. (United States Government Accountability Office: Washington, DC)

Gould JS (1988) Validation of the Rothermel fire spread model and related fuel parameters in grasslands fuels. In ‘Proceedings of the Conference on Bushfire Modelling and Fire Danger Rating Systems’, 11–12 July 1988. (CSIRO: Canberra)

Grishin AM (1996) Mathematical modelling of forest fires. In ‘Fire in Ecosystems of Boreal Eurasia’. (Ed. V Furyaev) pp. 314–325. (Kluwer Academic Publishers: Dordrecht, the Netherlands)

Grishin AMGruzin ADZverev VD1985Study of the structure and limits of propagation of the front of an upstream forest fire.Combustion, Explosion, and Shock Waves21918

Hirsch KG (1996) Canadian forest fire behavior prediction (FBP) system: user’s guide. Special Report 7. Canadian Forest Service, Northwest Region, Northern Forestry Centre. (Edmonton, AB)

Hough WQ (1969) Caloric value of some forest fuels of the southern United States. USDA Forest Service, Southeastern Forest Experiment Station Research Note SE-120. (Asheville, NC) Available at [Verified 18 October 2006]

Incropera FP, Dewitt DP (1996) ‘Fundamentals of Heat and Mass Transfer.’ (John Wiley & Sons: New York)

Johnson EA, Miayanishi K (Eds) (2001) ‘Forest Fires: Behavior and Ecological Effects.’ (Academic Press: San Diego)

Larini MGiroud FPorterie BLoraud J-C1998A multiphase formulation for fire propagation in heterogeneous combustible media.International Journal of Heat and Mass Transfer41881897doi:10.1016/S0017-9310(97)00173-7

Linn RR (1997) A transport model for prediction of wildfire behavior. PhD thesis, New Mexico State University.

Linn RCunningham P2005Numerical simulations of grass fires using a coupled atmosphere–fire model: Basic fire behavior and dependence on wind speed.Journal of Geophysical Research110D13107doi:10.1029/2004JD005597

Linn RReisner JColman JJWinterkamp J2002Studying wildfire behavior using FIRETEC.International Journal of Wildland Fire11233246doi:10.1071/WF02007

Margerit JSero-Guillaume O2002Modelling forest fires: Part II: reduction to two-dimensional models and simulation of propagation.International Journal of Heat and Mass Transfer4517231737doi:10.1016/S0017-9310(01)00249-6

McGrattan KB (Ed.) (2004) Fire Dynamics Simulator Version 4: Technical Reference Guide. NISTIR, Special Publication 1018. (National Institute of Standards and Technology: Gaithersburg, MD) Available at [Verified 18 December 2006]

Mell WEMcGrattan KGBaum HR1996Numerical simulation of combustion in fire plumes.Proceedings of the Combustion Institute2615231530

Mell WE, Charney JJ, Jenkins MA, Cheney P, Gould J (2005) ‘Numerical simulations of grassland fire behavior from the LANL-FIRETEC and NIST-WFDS models.’ EastFIRE Conference, 11–13 May, George Mason University, Fairfax, VA.

Mell W, Maranghides A, Rehm R, Manzello S, Forney G, Jenkins MA, Sun R, Krueger S (2007) ‘Wildland–Urban Interface and Wildland Fires.’ Available at [Verified January 2007]

Morvan DDupuy JL2001Modeling fire spread through a forest fuel bed using a multiphase formulation.Combustion and Flame12719811984doi:10.1016/S0010-2180(01)00302-9

Morvan DDupuy JL2004Modeling the propagation of a wildfire through a Mediterrean shrub using a multiphase formulation.Combustion and Flame138199210doi:10.1016/J.COMBUSTFLAME.2004.05.001

Morvan D, Tauleigne V, Dupuy JL (2002a) ‘Flame Geometry and Surface to Crown Fire Transition During the Propagation of a Line Fire Through a Mediterranean Shrub.’ (Millpress: Rotterdam)

Morvan D, Tauleigne V, Dupuy JL (2002b) ‘Wind Effects on Wildfire Propagation Through a Mediterranean Shrub.’ (Millpress: Rotterdam)

Murphy PJ, Mudds JP, Stocks BJ, Kasischke ES, Barry D, Alexander ME, French NHF (2000) Historical fire records in the North American boreal forest. In ‘Ecological Studies, Vol. 138, Fire, Climate Change, and Carbon Cycling in the Boreal Forest’. (Eds ES Kasischke, BJ Stocks) pp. 274–288. (Springer-Verlag: New York)

Noble IRBary GAVGill AM1980McArthur’s fire-danger meters expressed as equations.Australian Journal of Ecology5201203doi:10.1111/J.1442-9993.1980.TB01243.X

Ohlemiller TCorley D1994Heat release rate and induced wind field in a large scale fire.Combustion Science and Technology97315330

Pagni PJPeterson TG1973Fire spread through pourous fuels.Proceedings of the Combustion Institute1410991107

Parker WJ (1989) Prediction of the heat release rate of douglas fir. In ‘Fire Safety Science – Proceedings of the 2nd International Symposium’, Tokyo, 13–17 June 1998. (Eds T Wakamatsu, Y Hasemi, A Sekizawa, PG Seeger, PJ Pagni, CE Grant) pp. 337–346. (Hemisphere Publishing: New York)

Pastor EZarate LPlanas EArnaldos J2003Mathematical models and calculations systems for the study of wildland fire behavior.Progress in Energy and Combustion Science29139153

Pitts WM1991Wind effects on fires.Progress in Energy and Combustion Science1783134doi:10.1016/0360-1285(91)90017-H

Porterie BMorvan DLarini MLoraud JC1998Wildfire propagation: a two-dimensional multiphase approach.Combustion, Explosion and Shock Waves34139150

Porterie BMorvan DLoraud JCLarini M2000Firespread through fuel beds: Modeling of wind-aided fires and induced hydrodynamics.Physics of Fluids1217621782

Quintiere JG (1997) ‘Principles of Fire Behavior.’ (Delmar Publishers: Albany)

Reisner JWynne SMargolin LLinn R2000Coupled atmosphere-fire modeling employing the method of averages.Monthly Weather Review12836833691

Rothermel RC (1972) A mathematical model for predicting fire spread in wildland fuels. USDA Forest Service, Intermountain Forest and Range Experiment Station General Technical Report INT-11. (Ogden, UT)

Sero-Guillaume OMargerit J2002Modelling forest fires: Part I: a complete set of equations derived by extended irreversible thermodynamics.International Journal of Heat and Mass Transfer4517051722doi:10.1016/S0017-9310(01)00248-4

Sneeuwjagt RJFrandsen WH1977Behavior of experimental grass fires vs. predictions based on Rothermel's fire model.Canadian Journal of Forest Research7357367

Stephens GL1984The parameterization of radiation for numerical weather prediction and climate models.Monthly Weather Review112826867

Stewart S, Radeloff V, Hammer R (2003) Characteristics and location of the wildland–urban interface in the United States. In ‘2nd International Wildland Fire Ecology and Fire Management Congress’, Orlando, FL, 19 November 2003. Available [Verified 18 December 2006]

Stock BJSimard AJ1993Forest fire management in Canada.Disaster Management52127

Susott RA1982Characterization of the thermal properties of forest fuels by combustible gas analysis.Forest Science2404420

UCSB (2005) ‘Southern California Wildfire Hazard Center.’ (University of Southern California: Santa Barbara) Available at [Verified 18 October 2006]

USDA Forest Service (2006) ‘Policy Implications of Large Fire Management.’ Available at [Verified 19 October 2006]

USFS BlueSky (2004) ‘Bluesky Modeling Framework to Predict Cumulative Impacts of Smoke From Agricultural, Forest, and Range Fires.’ Available at [Verified 18 October 2006]

Weber RO1991Modelling fire spread through fuel beds.Progress in Energy and Combustion Science176782doi:10.1016/0360-1285(91)90003-6

Westerling ALHidalgo HGCayan DRSwetnam TW2006Warming and earlier spring increases western US forest wildfire activity.Science313940943

Williams FA1982Urban and wildfire fire phenomenology.Progress in Energy and Combustion Science8317354doi:10.1016/0360-1285(82)90004-1

Zhou XYPereira JCF2000A multidimensional model for simulating vegetation fire spread using a porous media sub-model.Fire and Materials243743doi:10.1002/(SICI)1099-1018(200001/02)24:1<37::AID-FAM718>3.0.CO;2-Q

Zicherman J (2004) Fire at the urban wildland interface: Performance of California homes and buildings. California Department of Forestry and Fire Protection, Technical Report IFB no. 5CA334189, FCA no. 05-6369. (Fire Cause Analysis: Richmond, CA)

Supplementary MaterialSupplementary Material 533 KB Export Citation