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Fire-Front Propagation Using the Level Set Method



Ronald G. Rehm, Randall J. McDermott


Propagation of an outdoor fire front in wildland or in a combination of wildland and structural fuels (the so-called wildland-urban interface or WUI fire), can be modeled as an initial-value problem using either a Lagrangian or an Eulerian description. The equations associated with each description are presented, and the methods used to solve the equations are discussed. Some comparisons between the two methods are also made. The emphasis in this report is on the Eulerian equations and on the level-set numerical method. Earlier studies had presented the Lagrangian formulation, and a method-of-lines solution. Advantages of the Eulerian/level-set method are discussed, and several examples that illustrate these advantages are presented.
Technical Note (NIST TN) - 1611
Report Number


level set method, mathematical model, outdoor fire spread, physics-based fire model, wildland-urban-interface


Rehm, R. and McDermott, R. (2009), Fire-Front Propagation Using the Level Set Method, Technical Note (NIST TN), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed May 21, 2024)


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Created April 1, 2009, Updated June 2, 2021