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Author Topic: Numerical Instability Errors with Cinema Fire - FDS Code  (Read 267 times)


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Numerical Instability Errors with Cinema Fire - FDS Code
« on: July 18, 2020, 04:45:21 am »

Hi All,

I am having some issues with modelling a cinema fire coupled with a HVAC system in FDS. I have attached the code below and any help / suggestions with this would be great. To give a bit more background, the simulation runtime is set at 600 seconds and it seems to run fine for the first ~490 seconds, before crashing and giving the numerical error. Looking at some of the pressure slice files (also attached), the pressure changes dramatically around the extract ductwork between around 480 and 490 seconds (temperature also changes in this manner), and I believe that the extract ductwork is the problematic area.

Please let me know your thoughts when you get a chance and if you require any further information.

Many thanks for your help,