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Unstable results

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Old   December 1, 2014, 02:29
Default Unstable results
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Faizan
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Hi all,

I have problem in velocity plot on cfx. The steady state response in cfx solver stabilized the velocity curve at 1200m/s which is the maximum velocity but the cfx velocity plot is showing some crazy numbers like 1.177exp+004 which is equal to 11770 nealy 12 thousands which is crazy...plzzzzzzzz help...
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Old   December 1, 2014, 04:03
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Glenn Horrocks
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First of all - please do not post new questions on existing threads. For a new question start a new thread.

Your question describes a typical result when the simulation has numerical instability. Instabilities can lead to overflow errors, so this FAQ is relevant: http://www.cfd-online.com/Wiki/Ansys...do_about_it.3F

But not all instabilities result in divergence. Sometimes you get unphysical results which are numerically stable - an example would be the "wiggles" in pressure and velocity at shock waves.
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