CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Visualization & Post-Processing Software > Tecplot

Tecplot 360 2013 Non Zero Velocity at the Wall with FLUENT data

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   July 24, 2014, 17:14
Default Tecplot 360 2013 Non Zero Velocity at the Wall with FLUENT data
  #1
New Member
 
Join Date: Oct 2013
Posts: 2
Rep Power: 0
LeDude is on a distinguished road
Hi Tecplot users!

This is my first post

Recently I decided to try and use Tecplot for post-processing Fluent data instead of the CFD Post Processor from Ansys.

However, when I load my Fluent .cas and .dat files using the Fluent data loader I get a non zero velocity at the walls of my domain. This is of course not physical due to the no slip condition. My guess is that Tecplot uses the data at the grid node adjacent to the wall.

If I plot the velocity at the wall using CFD Post from I get a zero velocity at the wall.

Has anyone else experienced this, and know of any solutions?

Kind Regards
LeDude is offline   Reply With Quote

Old   July 25, 2014, 19:39
Default
  #2
Senior Member
 
Scott Rumage
Join Date: May 2009
Location: Seattle, WA
Posts: 152
Rep Power: 17
scott_rumage is on a distinguished road
This is a known issue as Fluent data files store their information at the cell centers, and Tecplot 360 plots from nodal values. Tecplot 360 reads Fluent's cell-centered information and extrapolates to the nodal locations. This extrapolation process yields a non-zero velocity at a surface for Fluent data.

One can eliminate this issue if the export from Fluent is specified as nodal (not cell-centered). The specification of cell or nodal values can be made in Fluent’s CGNS data export. Information stored at the nodes will show will show a zero velocity at the wall in Tecplot 360.

Scott
scott_rumage is offline   Reply With Quote

Old   July 26, 2014, 14:49
Default
  #3
New Member
 
Join Date: Oct 2013
Posts: 2
Rep Power: 0
LeDude is on a distinguished road
Hi Scott,

Thank you for the answer.

I tried doing as you suggest, but when I import the CGNS file with the node centered data all variables have the value zero in the entire domain.

I also tried using "Specify Equation" in Tecplot to assign zero velocity to all the velocity components at the wall. Now if I make a contour plot of the velocity magnitue on the wall I get a value of zero everywhere.

However, if I make a vector plot of a slice plane, Tecplot still draw velocity vectors at the wall nodes.

Is there any way to circumvent this? I have attached an image to illustrate the situation.

Regards
Attached Images
File Type: jpg TecplotPic.jpg (55.8 KB, 37 views)
LeDude is offline   Reply With Quote

Old   July 28, 2014, 19:11
Default
  #4
Senior Member
 
Scott Rumage
Join Date: May 2009
Location: Seattle, WA
Posts: 152
Rep Power: 17
scott_rumage is on a distinguished road
Sorry that I wasn't of much help. I don't have any suggestions other than to double check that the CGNS export file from Fluent was specified as having the data at the nodes.

When I did this type of export, I did have zero velocity at the wall and the remaining domain data appear as expected.

Scott
scott_rumage is offline   Reply With Quote

Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
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 Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Tecplot with fluent Rafael FLUENT 7 February 9, 2018 01:57
[GAMBIT] periodic faces not matching Aadhavan ANSYS Meshing & Geometry 6 August 31, 2013 12:25
Wall function formulation in CFX and Fluent gravis ANSYS 0 May 4, 2010 12:03
Exporting data to Tecplot 360 Genesis FLUENT 2 June 6, 2007 18:53
fluent case n data files not exporting to tecplot krishna FLUENT 2 February 18, 2007 00:24


All times are GMT -4. The time now is 19:08.