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Old   August 8, 2008, 07:04
Default Transient Case
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MAB
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I am getting around 6 million cells and it is a transient case. How long you think CFX will take to complete this simulation. the smallest cell is about 0.005m . any advice about time step. (coz it is crashing on first loop naming it a Fatal Over Flow). any advice please? thanks
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Old   August 8, 2008, 07:50
Default Re: Transient Case
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Rogerio Fernandes Brito
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Did you create any own material? (donīt forget the input the Cp, ro (density), and K).

You might have at least 8 GB of RAM!

Change the turbulence model (and the same for the scheme of convection)

Decrease the time step. (use 0.1 s)

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Old   August 11, 2008, 01:17
Default Re: Transient Case
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Glenn Horrocks
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Hi,

6M cells in a low Re simulation - easy, quick, but need a bit of memory. 6M cells in a multiphase, transonic, reacting flow with mesh motion - you will need a supercomputer.

Without more detail we cannot help.

Glenn Horrocks
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Old   August 11, 2008, 06:02
Default Re: Transient Case
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MAB
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Hi thanks I think it is low Re , multiphase flow( water waves) ...what do you think about it. do i still need a supercomputer???
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Old   August 11, 2008, 18:39
Default Re: Transient Case
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Glenn Horrocks
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Hi,

Modelling water waves is tricky and slow on CFX. Again it still depends on many things but you should be able to run on a machine with a good deal of RAM (or better still a cluster). If you are just modelling water waves you will probably find better software which will run much faster.

Glenn Horrocks
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Old   August 12, 2008, 04:56
Default Re: Transient Case
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MAB
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Thanks Glenn, Could you please suggest me anyother sofware for this pupose of modellling water waves. thanks MAB
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Old   August 12, 2008, 22:33
Default Re: Transient Case
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Glenn Horrocks
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Hi,

We have fluent and CFX and fluent does it much better. There are also myriads of other software for coast and ship design which are worth looking into.

Glenn Horrocks
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Old   August 13, 2008, 07:52
Default Re: Transient Case
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MAB
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does fluent has moving mesh or cut cell capability???
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