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Can we model k epsilon without wall function?

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Old   March 14, 2022, 21:50
Default Can we model k epsilon without wall function?
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parth
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I am modelling a dissimilar heated plate with a small 2D domain (200 mm x 200 mm). I wanted to compare different turbulent models for my problem. But for the k epsilon model, the first layer height (estimated from online y+ calculators) is coming around 0.06 m (for y+ of 30), which is too much coarse mesh for my domain. Is it possible to go with a fully resolved approach for k epsilon model? How we can do it in OpenFoam? I can resolve the mesh for y+ ~1, as the domain is small and 2D.
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Old   March 15, 2022, 11:48
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k-e is a high Reynold approach. Therefore it is easy holding y+ between 30 andd 300, as recommended.

If you have such a large y+, you don't have a high Reynold situation.

You don't need a wall function if you have y+ in the near of 1, because your simulation resolves the viscous sublayer..
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Old   March 15, 2022, 21:31
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Thank you..!!
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k-epsilon, low re k-e, wall functions, y plus

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