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morteza08 February 2, 2011 18:16

first grid size for a given y-lus
i am going to model a turbulent flow over a flat plate.
if i want to extract a given y-plus, how can i set the first grid size?
is there any formula to calculate the distance between wall and first grid in a given flow?

thank you in advance

f-w February 2, 2011 19:03

morteza08 February 2, 2011 19:27


Originally Posted by f-w (Post 293362)

thank you dear friend
another question.. i mentioned that i want to model a flat plate.. is this calculator can be used for flow over any arbitrary geometry or this is only for flat plate?

f-w February 3, 2011 13:05

At the top of the page:

"This page provides a worksheet for estimating the normal spacing to be used in a viscous CFD grid. Estimates are for a turbulent flat plate in free air and are based on the Sutherland formula for viscosity."

It's a good starting point for arbitrary geometry. Run your simulation (not necessarily until convergence) and plot y+; then adjust mesh accordingly.

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