FDS is a Computational Fluid Dynamics (CFD) model of fire-driven fluid flow. The model solves numerically
a form of the Navier-Stokes equations appropriate for low-speed, thermally-driven flow with an
emphasis on smoke and heat transport from fires. The partial derivatives of the conservation equations of
mass, momentum and energy are approximated as finite differences, and the solution is updated in time
on a three-dimensional, rectilinear grid. Thermal radiation is computed using a finite volume technique
on the same grid as the flow solver. Lagrangian particles are used to simulate smoke movement, sprinkler
discharge, and fuel sprays.
Smokeview is a companion program to FDS that produces images and animations of the results. In
recent years, its developer, Glenn Forney, has added to Smokeview the ability to visualize fire and smoke in
a fairly realistic way. In a sense, Smokeview now is, via its three-dimensional renderings, an integral part of
the physical model, as it allows one to assess the visibility within a fire compartment in ways that ordinary
scientific visualization software cannot.
Although not part of the FDS/Smokeview suite maintained at NIST, there are several third-party and
proprietary “add-ons” to FDS either available commercially or privately maintained by individual users.
Most notably, there are several Graphical User Interfaces (GUIs) that can be used to create the input file
containing all the necessary information needed to perform a simulation.