Natural Ventilation using FDS / OpenFOAM

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I'm interested in natural ventilation. Has anyone used NIST FDS or OpenFOAM
to successfully model natural ventilation?
Are there any open source programs out there capable of this?
Any recommendations for natural ventilation modeling references?


Shariq Ali EIT, LEED AP BD+C

Shariq_Ali at's picture
Joined: 2011-10-01
Reputation: 200


We have successfully used IES ( for bulk flow analysis in
naturally ventilated buildings. Maybe someone else is familiar with an
open-source package capable of modeling natural ventilation with
acceptable accuracy.

Some good sources to review are:

Natural Ventilation in Buildings

Natural Ventilation in the Urban Environment

Ventilation of Buildings

ASHRAE Fundamentals

Hope this is helpful.


Tim Reynolds's picture
Joined: 2011-10-02
Reputation: 0


We have used NIST to carry out evaluations of nat vent designs fairly
successfully. Obviously it goes without saying that boundary
conditions are very important here. We have open foam as well but
haven't carried out nat vent designs in it yet.

Similarly to IES the offering from Designbuilder is a good tool which
we have used a number of times for such buildings. It uses the
energyplus simulation engine and the results of your simulation can be
linked to the CFD model.

I am due to give a webinar on the 23 march on it's use for this
purpose and I would suggest it might be useful for you to register for
it. I believe further details are available on the designbuilder
website ( This software is very
competetively priced and has a very intuitive GUI & modelling process.

ESPr might offer another option but I can't offer any advice on it's
Cfd capabilities though I do believe it has them albeit fairly crude.
It's thermal modelling engine is open source and it has some advanced
modelling capabilities beyond many commercial tools. It's user
interface is in my own opinion quite hard to use. But if you are
happy with nist and openfoam my guess us that text based modelling
doesn't phase you.

Hope this is helpful.

Kind Regards

Dr Paul Carey

Paul Carey's picture
Joined: 2011-10-02
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