USDA Forest Service

Fire and Environmental Research Applications Team


Fire and Environmental Research Applications Team
Pacific Wildland Fire Sciences Laboratory

400 N 34th Street, Suite 201
Seattle, WA 98103

(206) 732-7800

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United States Department of Agriculture Forest Service.

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Wildland-Urban Fire Dynamics Simulator (WFDS)

News! NIST, Forest Service Propose System to Help Communities Resist Wildfires (12/12/12)

Large fire smoke plume"The subject of WUI fire research falls between traditional studies of 'building fires' and 'forest fires'..."

Despite the increasing frequency and losses of structures(homes) in areas prone to wildfire, there has been relatively little research in how fires spread from the wildlands to the more urban lands, compared to fires within structures. This is due, in part, to the fact that the subject of WUI fire research falls between traditional studies of "building fires" and "forest fires", non-overlapping areas that in the past have been the responsibility of different branches of the government. To date, no study that measures the effectiveness of current risk mitigation practices, whether through wildland fuel treatments or modification of residential fuels, has been conducted.

"There has been very little research in how fires spread from the wildlands to the more urban lands."

Traditionally, passive and active fire protection measures in structures have been aimed at limiting the spread and damage from a fire initiating inside the home. A paradigm shift is needed for structures that resist ignitions from both the inside and outside. However, very little quantitative information is available on the actual exposure experienced by structures in WUI fire settings.

This extension of FDS is underway as part of a cooperative research program between the wildland-urban interface programs of the Pacific Wildland Fire Sciences Laboratory, and the National Institute of Standards and Technology.

Project Overview

The wfdscycle Field Data Collection Data Laboratory measurements Modeling wildland-urban interface fire dynamics simulator (WFDS) extends the fire dynamics simulator (FDS), which has been developed for structural fires, to account for the presence of terrain and/or vegetation and the spread of fires through vegetation.

WFDS uses computational fluid dynamics methods to solve the governing equations for buoyant flow, heat transfer, combustion, and the thermal degradation of vegetative fuels. The solution method makes use of large eddy simulation techniques to solve the gas-phase equations on computational grids that are too coarse to directly resolve the detailed physical phenomena.

WFDS is fully integrated in FDS. However, the most recent implementation of WFDS is always on this webpage. The version of WFDS on the FDS webpage may somewhat lag behind the version found here.

This page contains links to wildland-urban interface fire computer models and example input files. Validation of these models is ongoing but far from complete. Please keep this in mind when using the Wildland-Urban Fire Dynamics Simulator (WFDS) to solve for problems outside the current scope of validation. See below for information on the current state of validation.

Brief History




We acknowledge funding from the Joint Fire Science Program under Project 07-1-5-08 and 11-2-1-11


Team Lead: Ruddy Mell

U.S. Forest Service - PNW- FERA
Last Modified: Monday, 16 December 2013 at 14:18:38 CST

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