. . . . . . . . . . .
BFRL Software . Link to NIST .
.
Link to Home Link to Research Areas Link to BFRL Publications Link to BFRL Software Link to BFRL Staff Information Link to Contact Information Link to Ask the Experts Section .

Fire Growth and Smoke Transport Modeling with CFAST

The Consolidated Model of Fire and Smoke Transport, CFAST, is a computer program that fire investigators, safety officials, engineers, architects and builders can use to simulate the impact of past or potential fires and smoke in a specific building environment. CFAST is a two-zone fire model used to calculate the evolving distribution of smoke, fire gases and temperature throughout compartments of a building during a fire. These can range from very small containment vessels, on the order of 1 m3 to large spaces on the order of 1000 m3.

The latest version of the software, until now a DOS program, is designed to work with Windows and has been tested with Windows 2000 and XP. The CFAST package includes NIST’s Smokeview program, which visualizes with colored, three-dimensional animations the results of the CFAST simulation of a specific fire’s temperatures, various gas concentrations and growth and movement of smoke layers across multi-room structures.

Obtaining CFAST

The latest version of the software is version 6.1.1. The software and documentation is available for download.

  • Install CFAST 6.1.1 (6.08 MB) -  This software requires the Microsoft .NET framework.  More information on the Microsoft .NET framework is available here:  http://www.microsoft.com/downloads.
     
  • CFAST User's Guide - The User's Guide for CFAST describes how to install the model, verify its correct installation, create input data in an appropriate form, and analyze of the output of a simulation.

  • CFAST Technical Reference Manual - The Technical Reference Manual for CFAST presents the underlying physical principles, provides a comparison with other models and experimental data, and includes a description of the limitations of the model.
     
  • CFAST Software Development and Model Evaluation Guide – The Software Development and Model Evaluation Guide includes documentation of the software quality assurance processes used in the development of CFAST and a broad range of validation tests of the current version of the model.

  • Documentation for Smokeview - CFAST Version 6 includes NIST's Smokeview program for visualization.
     
  • Source Code – Source code for the latest development version of the model is available on the CFAST development site.
     
  • FAQs - Frequently asked questions for CFAST.

  • CFAST Examples - Some typical examples of commonly encountered scenarios.

  • Version History - A version history of CFAST is available.
     
  • Archive - Older versions of the model are also available.

Support Options

We are interested in hearing your comments and suggestions. Many of the improvements to date in both CFAST and Smokeview are a result of feedback we have already received from users of the software.

Please go to the Discussion Group, for general questions and/or to provide feedback related to your experience using CFAST, Smokeview, the documentation, the web sites, etc. Often this will resolve your issue without reporting a specific bug to the developers.

Report to the Support Issue Tracker specific bugs or problems that you encounter with either CFAST or Smokeview.

See the Support page for more options.

What's New in CFAST

The most recent version of CFAST is version 6.1.1.  New to this version:

  • Added a new species, labeled TS, to track flow through compartments. TS is a trace species produce during pyrolysis and is not affected by combustion. The assumption is that molecules are large enough to be filtered, but that mass is small compared to the overall pyrolysis. See NISTIR 7498 for an example of its use.
  • Added the ability to specify filtering for mechanical ventilation systems which applies to soot and the trace species. For the user, it is implemented with the EVENT,F command and available through the GUI. See the User’s Guide, NIST Special Publication 1041 (May 2008 Revision) for details.
  • Separated pyrolysis and combustion kinetics. The original purpose was to fix a bug related to pyrolysis products not being transported to the upper layer when a fire is only in the upper layer. The code was structured so that a consistent combustion model for a plume could be implemented. Species affected only by pyrolysis are hydrogren choloride, hydrogen cyanide, trace species and the concentration time product. Species affected only by kinetics are carbon-dioxide, carbon-monoxide, and soot. Species affected by both are oxygen and fuel. Nitrogen is inert and only transported.
  • Corrected error in mechanical ventilation that prevented flow from dropping off at high pressures like it was supposed too. An additional error caused DASSL to fail at times when the mechanical ventilation system shut off due to (the now corrected) high pressure cutoff.  The solution was to not totally close the vent (the vent is left open at an extremely small value, machine epsilson for double precision)  Corrected error in exe handle routine that caused model to fail with path names longer than 128 characters (windows limit is 255 characters for whole file name).  Corrected error in interpolation routines for opening and closing vents that did not smoothly transition from open to closed (Since the GUI did this over 1 s, the impact should not be noticeable for previously run cases).
  • Incorporated Heskestad plume model as an alternative to the McCaffrey plume model (type 2).  There is a small difference in the calculated results for a range of test cases (on the order of 2% to 4%).  The plan is to add plume temperature to the calculation as well.
  • Corrected error in the GUI that incorrectly outputs the mechanical ventilation specification for the CFAST model.  The fifth parameter on the line specifies a "system number" for each mechanical ventilation system.  In older versions, this began with 1 for each compartment rather than being numbered sequentially throughout.  The impact was that opening and closing of vents would not work when there were mechanical ventilation fans in more than one compartment.  Calculation was correct for fully-opened mechanical vents.

CFAST is developed by the National Institute of Standards and Technology (NIST) of the United States Department of Commerce. CFAST is free software developed through the National Institute of Standards and Technology (NIST) by employees of the Federal Government in the course of their official duties. Pursuant to Title 17, Section 105 of the United States Code, this work is not subject to copyright protection and is in the Public Domain.  

NIST assumes no responsibility whatsoever for use by other parties of its source code, documentation or compiled executables, and makes no guarantees, expressed or implied, about its quality, reliability, or any other characteristic. See the Disclaimer page for additional information.

 


Graphic Rule

Privacy Policy/Security Notice  |  Disclaimer  |  FOIA

NIST is an agency of the U.S. Department of Commerce

 BFRL Logo

Last updated:  4/7/2009