# Near-wall treatment for k-omega models

(Difference between revisions)
 Revision as of 18:05, 19 December 2008 (view source)Peter (Talk | contribs)m (Reverted edits by AcletOlaer (Talk) to last version by Jola)← Older edit Revision as of 05:09, 29 July 2009 (view source)Baldy (Talk | contribs) m (spelling)Newer edit → Line 14: Line 14: If '''Transitional Flows option is not active''', then the mesh guidelines should be the same as for the wall functions.
If '''Transitional Flows option is not active''', then the mesh guidelines should be the same as for the wall functions.
- ''(For [...] wall functions, each wall-adjacent cell's centroid should be located within the log-law layer,  30 < y+ < 300. A y+ value close to the lower bound '''y+ = 30''' is most desirabl.)'' + ''(For [...] wall functions, each wall-adjacent cell's centroid should be located within the log-law layer,  30 < y+ < 300. A y+ value close to the lower bound '''y+ = 30''' is most desirable.)''

## Revision as of 05:09, 29 July 2009

Both k- omega models (std and sst) are available as low-Reynolds-number models as well as high-Reynolds-number models.

The wall boundary conditions for the k equation in the k- omega models are treated in the same way as the k equation is treated when enhanced wall treatments are used with the k- epsilon models.

This means that all boundary conditions for
- wall-function meshes will correspond to the wall function approach, while for the
- fine meshes, the appropriate low-Reynolds-number boundary conditions will be applied.

that means:

If the Transitional Flows option is enabled in the Viscous Model panel, low-Reynolds-number variants will be used, and, in that case, mesh guidelines should be the same as for the enhanced wall treatment
(y+ at the wall-adjacent cell should be on the order of y+ = 1. However, a higher y+ is acceptable as long as it is well inside the viscous sublayer (y+ < 4 to 5).)

If Transitional Flows option is not active, then the mesh guidelines should be the same as for the wall functions.
(For [...] wall functions, each wall-adjacent cell's centroid should be located within the log-law layer, 30 < y+ < 300. A y+ value close to the lower bound y+ = 30 is most desirable.)

Reference: FLUENT 6.2 Documentation, 2006