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Old   December 15, 2006, 14:17
Default wall function for low Re
M. Essuri
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we can not meet the y+ criteria (y+>30) for all the nodes for a low Re flow (Re= 500,000 )over an airfoil using Ke model with standard wall function treatment. Fluent was not responding to grid coarsening. Is it possible to meet the y+ criteria without jeoperdising the grid independence or we must go to enhanced wall treatment option? a reply is highly appreciated!!
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Old   December 15, 2006, 14:51
Default Re: wall function for low Re
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I have the same problem with the grid coarsening on the wall. I don't know why fluent doesn't respond to that.

I'm modeling an incompresible flow with Re=1x10^7 and I'm trying to get Y+ near 30 using k-e and standar wall treatment, but i have problem with the turbulent viscocity and the shear stress on the wall.

sorry, i can't help you because i have a similar problem if you find something, please tell me
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Old   December 18, 2006, 04:11
Default Re: wall function for low Re
Ralf Schmidt
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I have no sollution to your problem, but I think, I know, why fluent does not respont to mesh coarsening:

The difficulty in adapting yplus is, that fluent can only modify the cell size by spliting the cells in half or by removing nodes. So the yplus will be either half or about dubble the former value.

So, design your grid with the right yplus BEFOR exporting it into fluent.

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