FDS Miscellaneous

[Kevin McGrattan <kevin.mcgrattan@nist.gov>]

All

I recently travelled to China for the IAFSS meeting, and was
happy to meet many FDS users for the first time. I saw
several nice papers involving FDS applications. This is very
beneficial for FDS development as it shows what is working
well and what is not. For those of you working with the FDS
source code, please keep in mind that improvement can only
be made if you first identify a problem with the current
version of FDS. Several papers I saw involved additions of
detailed turbulence subroutines to FDS that were not
well-motivated. LES is a trendy subject in CFD, and there
are many researchers who use very elaborate sub-grid
algorithms. I have yet to see any benefit to most of these
sub-models, but if you feel strongly that there is one,
demonstrate its effectiveness when compared to the current
version of FDS and to experiment. It is not enough to simply
implement the routine. You have to explain why it is better
than what is there now. Frankly, I think that the basic
hydrodynamic solver is the strongest element of FDS. If you
want to make improvements, look at things like heat flux,
under-ventilation, flame spread, pyrolysis, etc.

Glenn Forney posted an upgraded Smokeview and FDS recently.
Mostly minor bug fixes.

There is a mistake in the FDS Users Guide related to smoke
detectors. It is not yet possible in FDS to trigger an
action based on the activation of a smoke detector. Thus,
SMOD_CREATE, SMOD_REMOVE, etc. do not work. These will work
in the next major release next year.

VTT has contributed a useful tool for creating animation
from Smokeview output. Check out fire.nist.gov/fds --> Tools
for details.

Kevin


-- 
Kevin McGrattan
National Institute of Standards and Technology
100 Bureau Drive, Stop 8663
Gaithersburg MD 20899-8663

Telephone: (301) 975 2712
FAX:       (301) 975 4052