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

aspect ratio

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

Reply
 
LinkBack Thread Tools Display Modes
Old   February 26, 2004, 11:50
Default aspect ratio
  #1
Joe
Guest
 
Posts: n/a
Hi you all!

I have problems to solve my calculation. I figured out that my aspect ratio is way to high. The cfx guideline tells me that if I use a thetra mesh I should have a maximum ar of 100.

Could someone please explain to me how the aspect ratio is defined and maybe how to lower it.

Thanks a lot

Joe
  Reply With Quote

Old   February 26, 2004, 12:06
Default Re: aspect ratio
  #2
Dang
Guest
 
Posts: n/a
For rotating machine, increasing the number of element in the span direction will reduce the aspect ratio.
  Reply With Quote

Old   February 26, 2004, 12:17
Default Re: aspect ratio
  #3
Joe
Guest
 
Posts: n/a
Yep, that`s what I thougt. ICEM just finished the new mesh. Hopefully it works better now.

Thank`s a lot,

Joe
  Reply With Quote

Old   February 26, 2004, 17:13
Default Re: aspect ratio
  #4
Glenn Horrocks
Guest
 
Posts: n/a
Hi Joe,

More generally, for a rectangular hex element, aspect ratio is defined as the longest edge length over the shortest edge length. For other element types there are other definitions (see the CAD2Mesh documentation), but they have the same idea of the longest element length over the smallest.

Element aspect ratio is a function of the way you have meshed your geometry. You have ended up with flat, wide elements somewhere.

Also keep in mind that hex elements run much better than tet elements at thigh aspect ratio, especially if the flow is aligned with the hex elements.

Regards, Glenn
  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
High aspect ratio oort OpenFOAM 5 September 16, 2011 15:06
pressure eq. "converges" after few time steps maddalena OpenFOAM Running, Solving & CFD 69 July 21, 2011 08:42
[ICEM] Mesh along axis for a wedge gives elements with extreme aspect ratio sangrampp ANSYS Meshing & Geometry 0 November 17, 2010 07:57
aspect ratio vs. y+ hammam CFX 3 August 6, 2007 11:41
High Aspect Ratio elements Flavio CFX 2 November 24, 2006 13:01


All times are GMT -4. The time now is 08:23.