FDS-SMV 6.5.0 Minor Release

This minor release is meant to address reports of numerical instabilities in tunnel fire cases with the recently released FDS 6.4.0, which may be attributed to relaxing the VN stability constraint from 0.5 to 1 in order to speed up calculations.

The key change implemented in FDS 6.5.0 is to include the baroclinic term in the pressure iteration scheme.  This corrects a time lag between the hyrdodynamic pressure in the baroclinic term and the output from the pressure Poisson equation.

Other improvements implemented in this version include an optional iteration in the radiation solve for multi-mesh simulations and more accurate interpolation of particle force terms.  More information is given in the Release Notes.

Here is a link to our Downloads page.

FDS-SMV 6.4.0 Minor Release

A new minor release, FDS-SMV 6.4.0, has been posted.  This release fixes a couple of issues with the combustion model.  The first was a bug in the reaction divergence expression that led to below ambient temperatures in some instances.  The second was a problem with boundedness for multiple reactions, mainly affecting complex chemistry.

https://pages.nist.gov/fds-smv/downloads.html

In this release we have also fixed several issues with MPI scaling.  With a time grant on the Oak Ridge National Lab supercomputer, Titan, we were able to run FDS on up to roughly 10,000 processes.  Linear scaling was achieved to roughly 16^3 mesh size (4096 cells/mesh).

For further details on this release see the FDS Release Notes.