CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > ANSYS > ANSYS Meshing & Geometry

Patch Independent Method, Problematic Geometry

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   July 15, 2010, 04:49
Unhappy Patch Independent Method, Problematic Geometry
  #1
New Member
 
Okan Isik
Join Date: Jul 2010
Location: Istanbul-Turkey
Posts: 2
Rep Power: 0
okan is on a distinguished road
Hi,

I am new in cfd, and this forum. I am using Ansys Fluent 12.01

I have a centrifugal pump impeller's fluid zone, I want to mesh it with using "patch independent method". But the "Named Selections" cause "problematic geometry" and it is always occurs on "named selections". if the "named selections" are deleted, there are no errors observed. When I delete "Named selections" I cant create required boundarys. How can I handle it?

If "Patch Indepentdent method" is wrong selection, which method is better for me?

My Fluid Zone is like that:


Okan
okan is offline   Reply With Quote

Old   July 19, 2010, 09:21
Default Refine the mesh to properly capture the Named Selection Boundaries
  #2
Senior Member
 
PSYMN's Avatar
 
Simon Pereira
Join Date: Mar 2009
Location: Ann Arbor, MI
Posts: 2,663
Blog Entries: 1
Rep Power: 47
PSYMN has a spectacular aura aboutPSYMN has a spectacular aura about
I remembered something about this, so I sent Ben Klinkhammer the link. He wrote back that...

Named selections force the PI mesh method to respect all the boundaries of the named selections. If there is not a named selection on a face, the PI mesh method will generally capture the faces, but could skip some of the edge boundaries. Putting a smaller size on the named selection faces will generally do the trick as then the mesher has an easier time capturing the boundaries. Reducing the sizes globally can also do the trick.

Unlike Patch Independent, Patch conforming mesh method meshes the edges first, then the faces, then the volume (PI meshes the volumes, then cuts out the faces, edges, etc.). So Patch conforming will generally not have the problem of capturing the edges, but you may get lower quality mesh as a result. (so you may still need to refine as necessary)

Generally when you run into this type of problem it is a result of a local mesh size being too large to get a good quality mesh that also captures the boundaries.

Hope this helps,
Ben
PSYMN is offline   Reply With Quote

Old   July 20, 2010, 10:57
Default
  #3
New Member
 
Okan Isik
Join Date: Jul 2010
Location: Istanbul-Turkey
Posts: 2
Rep Power: 0
okan is on a distinguished road
Thanks for your answer. I am followed the information you given me. It is working but the skewness is a little higher.

Thanks very much...

Okan
okan is offline   Reply With Quote

Reply

Tags
ansys 12, patch independent, problematic geometry

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
Problematic geometry reported smillerhh FLUENT 1 December 7, 2006 11:42
[Gmsh] Import gmsh msh to Foam adorean OpenFOAM Meshing & Mesh Conversion 24 April 27, 2005 08:19
comments on FDM, FEM, FVM, SM, SEM, DSEM, BEM kenn Main CFD Forum 2 July 18, 2004 18:28
Adaptive optimization of geometry Jan Rusås CFX 1 September 16, 2000 02:38
Virtual/Real geometry. Jack Keays FLUENT 9 June 15, 2000 23:39


All times are GMT -4. The time now is 21:09.