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Wall-bounded Compressible Steady State & LES: Odd Results: Why?

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Old   August 16, 2021, 04:00
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Arthur
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It seems like the solution is to change the back flow specification from 'normal to boundary' to 'neighboring cells'. This way the back flow along the top face eventually dies back down to 0.1% or 0.0%, and the flow field looks normal again, converging to E-6.

It's still weird why it works for Mesh 3.9 but not 3.10...
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Old   August 16, 2021, 06:25
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Quote:
Originally Posted by artkingjw View Post
It seems like the solution is to change the back flow specification from 'normal to boundary' to 'neighboring cells'. This way the back flow along the top face eventually dies back down to 0.1% or 0.0%, and the flow field looks normal again, converging to E-6.

It's still weird why it works for Mesh 3.9 but not 3.10...
The alternative is to make the domain absolutely huge. I tried a new mesh that's twice the height of Mesh 3.10 (which is already ~ 40-50 deltas), and that mesh does not report reverse flow issues.
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Old   August 17, 2021, 04:34
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Lorenzo Galieti
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I am a bit puzzled by it as well, because when I looked at the size of your domain, it seemed large enough
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