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

[ICEM] Equal Spacing on all the edges

Register Blogs Community New Posts Updated Threads Search

Like Tree8Likes
  • 1 Post By Tarantino
  • 1 Post By stuart23
  • 2 Post By PSYMN
  • 1 Post By PSYMN
  • 3 Post By PSYMN

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   March 13, 2013, 15:54
Default Equal Spacing on all the edges
  #1
Member
 
Tarantino
Join Date: Feb 2013
Posts: 46
Rep Power: 13
Tarantino is on a distinguished road
Hi !

I work with the geometry which including so many blocks. I want to know how can I define an equal spacing for the whole edges, so ICEM decide how many nodes should assign to have the spacing?
For instance, I have two blocks with two difference edge length. for the first I should assign 20 nodes to achieve spacing 0.1 and for the next I should assign 10 node to have 0.1 spacing. Is it possible that I just assign 0.1 as spacing and not Number of nodes? or is it possible to equalized the spacing in different blocks?
In ICEM Pre-Mesh Parameters > Mesh Parameters ones can set number of the nodes and not spacing.
I try Match Edges, but it is not working for this purpose!
thanks
asal likes this.
Tarantino is offline   Reply With Quote

Old   March 13, 2013, 19:56
Default
  #2
Senior Member
 
Stuart Buckingham
Join Date: May 2010
Location: United Kingdom
Posts: 267
Rep Power: 25
stuart23 will become famous soon enoughstuart23 will become famous soon enough
Tarantino,

ICEM does not work like that. For instance, what spacing would you have if you had parallel edges on one block with different lengths?

If your geometry is purely orthogonal, then the method you described would work, however 99.99% of geometries do not contain purely orthogonal parts, and so specifying the number of nodes is the most reliable way.

Stu
asal likes this.
stuart23 is offline   Reply With Quote

Old   March 14, 2013, 08:15
Default
  #3
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
Actually, what I would do, at least to start, is specify 0.1 on the geometry (Mesh tab => Part size setup or something like that). Then when my blocking topology is mostly laid out, I go to blocking => Premesh Params => Update Sizes... This seeds my blocking based on the sizes. But you would end up with that size being a max size. So the count would be set on the shortest edge and would propagate to all the parallel edges...

Stu is right about that being the way things work...
asal and afnch like this.
__________________
-----------------------------------------
Please help guide development at ANSYS by filling in these surveys

Public ANSYS ICEM CFD Users Survey

This second one is more general (Gambit, TGrid and ANSYS Meshing users welcome)...

CFD Online Users Survey
PSYMN is offline   Reply With Quote

Old   March 15, 2013, 09:35
Default
  #4
Senior Member
 
Astio Lamar
Join Date: May 2012
Location: Pipe
Posts: 186
Rep Power: 13
asal is on a distinguished road
This is great. I have also the same issue, but it is work now!
Is it possible to define a default ratio and spacing 1, spacing 2 for the whole blocks also?

For instance the default ration is 2, but I want to assign 1.2 far all edges. Can I do that?

Also I want to know more about Space Relative, Copy absolute, Linked bunching
as well as Match Edge option. I try Match Edge, but I cannot work with it!

Thanks in advance for your reply.
asal is offline   Reply With Quote

Old   March 15, 2013, 09:47
Default
  #5
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
Sure, You can adjust the default bunching ratio.

Look under Settings => Meshing Options => Hexa Meshing Options.

You can't setup a default for the initial spacing because that is much more model sizing and edge length dependent.

As for Copying edge distributions, "relative" means relative to the edge length. Absolute means match the actual initial height measurement.

Linked bunching is tricky until you realize that you just need to select the lower end of each set... Turn on bunching and notice the arrows... For the linked bunching, you want to select the edges at the base of the arrow. This should be well explained in the help.

Matching the end spacing is pretty easy. You select the sorce edge and the target edge(s) and it takes the end spacing from the one and copies it to the others... If you use the automatic method, you can't pick which is the source, so there are some options in there to chose if you keep the smallest, average or largest end spacing...
asal likes this.
__________________
-----------------------------------------
Please help guide development at ANSYS by filling in these surveys

Public ANSYS ICEM CFD Users Survey

This second one is more general (Gambit, TGrid and ANSYS Meshing users welcome)...

CFD Online Users Survey
PSYMN is offline   Reply With Quote

Old   March 15, 2013, 12:00
Default
  #6
Senior Member
 
Astio Lamar
Join Date: May 2012
Location: Pipe
Posts: 186
Rep Power: 13
asal is on a distinguished road
thanks for your reply.
just one more question. Is it possible to know the number of elements before convert the unstruct mesh? after it we can see it in mesh info.
asal is offline   Reply With Quote

Old   March 15, 2013, 13:13
Default
  #7
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
Yes, right click on Pre-mesh in the blocking branch of the tree and select "pre-mesh info".
asal, FJSJ and afnch like this.
__________________
-----------------------------------------
Please help guide development at ANSYS by filling in these surveys

Public ANSYS ICEM CFD Users Survey

This second one is more general (Gambit, TGrid and ANSYS Meshing users welcome)...

CFD Online Users Survey
PSYMN is offline   Reply With Quote

Reply


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
[snappyHexMesh] SnappyHexMesh for internal Flow vishwa OpenFOAM Meshing & Mesh Conversion 24 June 27, 2016 08:54
[snappyHexMesh] No layers in a small gap bobburnquist OpenFOAM Meshing & Mesh Conversion 6 August 26, 2015 09:38
[snappyHexMesh] snappyHexMesh won't work - zeros everywhere! sc298 OpenFOAM Meshing & Mesh Conversion 2 March 27, 2011 21:11
[snappyHexMesh] snappyHexMesh aborting Tobi OpenFOAM Meshing & Mesh Conversion 0 November 10, 2010 03:23
[snappyHexMesh] external flow with snappyHexMesh chelvistero OpenFOAM Meshing & Mesh Conversion 11 January 15, 2010 19:43


All times are GMT -4. The time now is 12:48.