Near-wall treatment for k-omega models
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Both k- omega models (std and sst) are available as low-Reynolds-number models as well as high-Reynolds-number models. <br> | Both k- omega models (std and sst) are available as low-Reynolds-number models as well as high-Reynolds-number models. <br> | ||
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If '''Transitional Flows option is not active''', then the mesh guidelines should be the same as for the wall functions.<br> | If '''Transitional Flows option is not active''', then the mesh guidelines should be the same as for the wall functions.<br> | ||
''(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 desirabl.)'' | ||
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| + | FLUENT 6.2 Documentation, 2006 <br> | ||
Revision as of 10:28, 18 May 2006
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 desirabl.)
Reference:
FLUENT 6.2 Documentation, 2006
