CFD Online Discussion Forums

CFD Online Discussion Forums (http://www.cfd-online.com/Forums/)
-   Main CFD Forum (http://www.cfd-online.com/Forums/main/)
-   -   first grid size for a given y-lus (http://www.cfd-online.com/Forums/main/84571-first-grid-size-given-y-lus.html)

morteza08 February 2, 2011 17:16

first grid size for a given y-lus
 
hi
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 18:03

http://geolab.larc.nasa.gov/APPS/YPlus/

morteza08 February 2, 2011 18:27

Quote:

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 12:05

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.


All times are GMT -4. The time now is 20:24.