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Old   March 11, 2009, 05:55
Default y+ range
  #1
Adam Stuchlik
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if I use SST without transitonal turbulence is it possible that values are wrong calculated when my y+ ranges from ~0.15 up to ~40?? briefly have I to model a grid with 30 < y+ < 300 w/o tt and 1 < y+ < 5 with tt to avoid wrong calculations? best wishes adam
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Old   March 11, 2009, 22:24
Default Re: y+ range
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Glenn Horrocks
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Hi,

It is always possible to get wrong results. There are a lot of things to get right before you get an accurate simulation.

If your question does SST need 30<y+<30 without the transition model and 1<y+1<5 with it the answer is no and no. The normal SST model is good for pretty much any y+ and the transition model requires y+<1.

Regards, Glenn

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Old   March 12, 2009, 04:44
Default Re: y+ range
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Adam Stuchlik
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Yes, this was the question. Thanks.

But how to generate efficiently a y+<1 grid? start with one, looking in post for regions y+>1 and then refining them? Or is there a way to precalculate y+ for a given grid??
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Old   March 12, 2009, 17:20
Default Re: y+ range
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Glenn Horrocks
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Hi,

The manual discusses techniques for estimating necessary grid resolution.

Otherwise do a simulation, work out the y+ and refining/coarsening based on the result.

Glenn Horrocks
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