# Problem with airflow pathlines in Fluent

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

December 18, 2011, 13:40
Problem with airflow pathlines in Fluent
#1
New Member

Evgeny Cherniakov
Join Date: Dec 2011
Location: Hong Kong
Posts: 4
Rep Power: 5
hello,

I've made an empty room's model in which airflow moves from ceiling to bottom/floor. There are 2D and 3D models. The top horizontal face (top horizontal edge for 2D model) was chosen as VELOCITY INLET. The bottom horizontal face (bottom horizontal edge for 2D model) was chosen as OUTFLOW.
The air velocity is constant and equals x=0; y=0; z=-0.5 m/s.
The feature of this model is that the volume of the room consists of 5 volumes with different mesh accuracy for 3D model and 4 areas for 2D model. (pictures 1 and 2)
As I know from Fluent or Gambit guide: all undetermined boundary conditions for faces (3D) or edges (2D) will be determined as a WALL. For that reason,I have determined all internal faces or edges as INTERIOR (picture 3 for 3D).
For calculation I have used standard k-epsilon turbulence model.
But after calculation, I saw strange picture . For 2D model it was O.K. - I have seen unidirectional downward pathlines. (picture 4)
But for 3D I have got strange whirl inside room model. (picture 5)
I used absolutely same parameters and data for both cases (i can give all data, if it will be necessary). I can not understand what is wrong with 3D model. (Mesh check did not show any problems).
Maybe, somebody have had same problem?
Attached Images
 pic_1 - 2D model mesh.png (24.5 KB, 12 views) pic_2 3D model mesh.png (64.5 KB, 8 views) pic_3 - 3D model interior faces.png (21.0 KB, 10 views) pic_4 - 2D model pathlines.png (11.7 KB, 9 views) pic_5 - 3D model pathlines from inlet.jpg (80.5 KB, 14 views)

 Tags 3 d modeling, airflow, k-epsilon model, mesh, pathlines

 Thread Tools Display Modes Linear Mode

 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 OffTrackbacks are On Pingbacks are On Refbacks are On Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post dunga82 FLUENT 8 April 19, 2012 20:23 kalyangoparaju ANSYS Meshing & Geometry 0 October 31, 2011 00:40 csvirume FLUENT 2 September 9, 2009 01:08 bobo FLUENT 2 July 3, 2009 06:28 brothershuai Main CFD Forum 0 July 1, 2009 15:41

All times are GMT -4. The time now is 13:55.