CFD Online Logo CFD Online URL
Home > Forums > FLUENT

wall function for low Re

Register Blogs Members List Search Today's Posts Mark Forums Read

LinkBack Thread Tools Display Modes
Old   December 15, 2006, 14:17
Default wall function for low Re
M. Essuri
Posts: n/a
we can not meet the y+ criteria (y+>30) for all the nodes for a low Re flow (Re= 500,000 )over an airfoil using Ke model with standard wall function treatment. Fluent was not responding to grid coarsening. Is it possible to meet the y+ criteria without jeoperdising the grid independence or we must go to enhanced wall treatment option? a reply is highly appreciated!!
  Reply With Quote

Old   December 15, 2006, 14:51
Default Re: wall function for low Re
Posts: n/a
I have the same problem with the grid coarsening on the wall. I don't know why fluent doesn't respond to that.

I'm modeling an incompresible flow with Re=1x10^7 and I'm trying to get Y+ near 30 using k-e and standar wall treatment, but i have problem with the turbulent viscocity and the shear stress on the wall.

sorry, i can't help you because i have a similar problem if you find something, please tell me
  Reply With Quote

Old   December 18, 2006, 04:11
Default Re: wall function for low Re
Ralf Schmidt
Posts: n/a

I have no sollution to your problem, but I think, I know, why fluent does not respont to mesh coarsening:

The difficulty in adapting yplus is, that fluent can only modify the cell size by spliting the cells in half or by removing nodes. So the yplus will be either half or about dubble the former value.

So, design your grid with the right yplus BEFOR exporting it into fluent.

  Reply With Quote


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
wall function and flow separation O.D.Y. FLUENT 1 October 3, 2011 16:27
latest OpenFOAM-1.6.x from git failed to compile phsieh2005 OpenFOAM Bugs 25 February 9, 2010 05:37
Two-phase air water flow problems by activating Wall Lubrication Force challenger85 CFX 5 November 5, 2009 06:44
Influece of wall velocity in the main flow marvin CFX 0 March 22, 2008 03:05
X-Y plot of Yplus in Fluent 5.3 Luo FLUENT 24 April 11, 2000 06:07

All times are GMT -4. The time now is 21:54.