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Ventilation simulations:should I go transient

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Old   May 14, 2008, 06:12
Default Ventilation simulations:should I go transient
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Tom
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I am running simulations (with a commercial CFD package) to determine the wind-driven natural ventilation of various building configurations under different wind indicences. My goal is to achieve steady state solutions.

I get a very good convergence, i.e. a reduction by 5 orders of magnitude for all varibles appart from turbulent dissipation which drops by 3 orders.

However, for some configurations I get a an unsteady regime developing in the room, with the main vortex moving from one sidewall to the other.

I know that I could run transient sims, then figure out the period of oscillation, then time average over that. However, my sims contain about 2 million cells, so to do that would take alot of time on my pentium4 32bit windows desktop.

So my question is can I accept the first steady state solution, given the good convergence?
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Old   May 22, 2008, 12:06
Default Re: Ventilation simulations:should I go transient
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Joel
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Hi Tom,

What CFD package are you using? We might be able to help with this depending on your answer.
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