Fire simulations with FDS

The Fire Dynamics Simulator (FDS) is a CFD-Code (Computational Fluid Dynamics) that serves to simulate fire. FDS simulates, inter alia, three-dimensional flows on the basis of the Navier-Stokes- equations; the underlying fire process; the spread of fire and fire smoke; thermal radiation. The program Smokeview visualizes the results. Temperature gradations, gas concentration and visibility can be displayed in the form of tables and diagrams.

The following issues can be treated with the help of FDS:

• combustion
• spread of smoke
• building unit temperatures

If applied for large volumes, high computer capacitance and time-consuming calculations (days, weeks) may be required.

Simulations with the zones model MRFC
The program package MRFC (Multi-Room-Fire-Code) is based on a multi-room- several-zones model. Linking randomly assigned rooms with several zones each, MRFC can calculate the determining parameters of conflagration, e.g. gas temperatures, building unit temperatures, pressure distribution and the resulting mass flows. With the Two-Zone model, the two layers inspected in the room consist of air and smoke gases for which a homogenuous distribution of temperature is assumed. Tables and diagrams show the results of temperature gradations, visibility, and gas concentrations.

MRFC can be implemented to examine:

• smoke (height of smoke layer, gas concentrations, etc)
• distribution of temperature
• determination of evacuation span (ASET)