CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > FLUENT

Size Functions in Gambit

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

Reply
 
LinkBack Thread Tools Display Modes
Old   December 8, 2003, 12:38
Default Size Functions in Gambit
  #1
chanchala
Guest
 
Posts: n/a
Hi,

For a curved geometry, I wanted to use Curvature Size Function. You are asked to specify: Angle, Growth rate, Distance and Size limit. I understand what Growth rate is but Gambit help files are pretty vague about the others. If anyone's used size functions please explain how I can make sense of these. I've had a few trials trying to mesh using the curvature size function but can't see any difference really.

thanks, Chanchi
  Reply With Quote

Old   December 9, 2003, 07:44
Default Re: Size Functions in Gambit
  #2
Rahul
Guest
 
Posts: n/a
Hi you have written as if you are compleing to Support group of Fluent. Anyway I have used Size function many times and found very usefull specially if you have many opening in a area and also area is iregular. Many time we can not get mesh without size funtion or we have to split areas. Size functions are good for free meshing only. Using Curvature Size Function may times you may not much difference with change in angle as Gambit will try to give better mesh by adjsting it. Actually we use shape function to get better controlled over mesh.

Size limit is max size of cell in that zone (area or edge) I hope I clarified your doubts.
  Reply With Quote

Old   December 9, 2003, 09:24
Default Re: Size Functions in Gambit
  #3
chanchala
Guest
 
Posts: n/a
Hi Rahul,

Sorry if it sounded as if I was complaining, after a whole afternoon playing with size functions I think I felt disheartened.

Thanks for your help. I hope maybe you can help me a bit more. I have to mesh a cylindrical pipe with tetrahedral mesh (for various reasons). I got a big difference in results when I compared results from a hex mesh to tet mesh so I asked fluent support why this may be. They said I should make sure that I use the right size function for the tet mesh. I thought perhaps curvature was the best one. Does the fact that applying this gives me no difference mean that there is no improvement necessary?

thanks again, chanchi
  Reply With Quote

Old   December 9, 2003, 09:50
Default Re: Size Functions in Gambit
  #4
Rahul
Guest
 
Posts: n/a
Usually you should use bit finer mesh when you go for tet. If you are having simple goemetry then you need not to go for size function. Even if you for size function go for fixed one instead of curved size function as it seems your geomery is not having so much curved faces. Best way to compare hex and tet resuts is compare grid-independent results. Rahul
  Reply With Quote

Reply

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
Gambit size function query Jon FLUENT 7 December 21, 2011 05:02
How could I add in 459 edges as the source of my face size function at once in GAMBIT sosososo1114 ANSYS Meshing & Geometry 1 September 30, 2011 00:47
How to modify geometry size in Gambit Axius ANSYS Meshing & Geometry 1 November 29, 2010 15:21
Phase locked average in run time panara OpenFOAM 2 February 20, 2008 15:37
Functions in Gambit Johnny FLUENT 0 March 27, 2004 03:49


All times are GMT -4. The time now is 14:43.