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

[ICEM] A question about model an architechture about vetilation

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   May 20, 2009, 05:18
Default A question about model an architechture about vetilation
  #1
New Member
 
sunny
Join Date: May 2009
Posts: 2
Rep Power: 0
sunnyonly is on a distinguished road
hi,everyone ,i am using icemcfd to model many architechtures and a outflowfield to simulate the ventilation.My problem is that ,i want to use tetra type about architechtures and hexa about outflow field ,what steps i can do to make it come true without errors.Thanks for any your honored answer.
sunnyonly is offline   Reply With Quote

Old   May 20, 2009, 05:20
Default
  #2
New Member
 
sunny
Join Date: May 2009
Posts: 2
Rep Power: 0
sunnyonly is on a distinguished road
it is only one body ,but how can i seperate many parts to do this mesh method?
sunnyonly is offline   Reply With Quote

Old   May 20, 2009, 19:50
Default
  #3
Member
 
Jules Bell
Join Date: May 2009
Posts: 32
Rep Power: 16
Jules is on a distinguished road
If you create your mesh from surface mesh, you can choose the mesh method individually for each surface patch.
"all quad" combined with "mapped" will give you a structured quadrilateral mesh (if number of nodes is equal on opposing edges), and a volume bounded by such surfaces should have structured hexa mesh.
"all tri" will lead to triangular surface mesh and tetrahedral volume mesh.
Jules is offline   Reply With Quote

Old   May 22, 2009, 14:08
Default Merge tet and hex mesh
  #4
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
Hello,

I have a ppt I could send you but it is 2MB. I can email it to you if you privately send me your email address…

In the mean time…

I am assuming that you have some building or group of buildings that are complicated and you don’t want to hexa mesh them, but you have a large far field that you want to hexa mesh…

You start by creating an interface between these regions… In ICEM CFD, you can use a Create Surfaces => primitive to create a box or sphere around your buildings. Then use the create intersection curve to intersect this primitive with the terrain. You can delete the part of the primitive outside of the domain (under ground) but it is not usually necessary. Name that interface geometry as “INTERFACE” or something like that. Put a material point inside the INTERFACE volume, if you want two materials, you could also put the other one outside (in the far field), but that is not needed.

I recommend saving the model as two geometry files. Save one copy as “Hexa_portion” and one as “Tetra portion”.

Then load the Hexa portion and generate the blocking for the region outside of the interface. Save this blocking and mesh. Close that project.

Open the Tetra portion and, if possible, delete the geometry outside of the interface. This will result in a smaller far field which will mesh more quickly with OCTREE. Setup and Mesh the tetra portion. Save.

Take care that the hexa mesh size at the interface is similar to the Tetra mesh size… Go back and adjust the hexa blocking if necessary. On the hexa side, also check the mesh size normal to the boundary, you want that to have similar volume elements to the tetra side. This usually means the hexa mesh size is a bit smaller than the tetra size…

Anyway, then go back and load the Hexa Portion (this is the full geometry). Load the hexa mesh and tetra mesh… When asked if you should replace or merge, choose merge. This actually just concatenates the meshes into the same file.

Once in ICEM CFD, go to mesh editing => Merge meshes. Select the INTERFACE part as the interface… It should work very easily… It is a very robust operation… It asks if you want to freeze anything, but you can leave that blank…

Afterward, you can convert tets to hexas, run prisms thru or whatever.

If you have any questions, Tech support at techsupp@ansys.com should be able to help.
Attached Images
File Type: jpg TetHexMerge.jpg (104.6 KB, 34 views)
PSYMN is offline   Reply With Quote

Old   September 23, 2010, 12:33
Default
  #5
New Member
 
VLKOH
Join Date: Mar 2009
Location: Malaysia
Posts: 20
Rep Power: 17
lalula2 is on a distinguished road
Hi PSYMN, currently I am using ICEM to model building and simulate the ventilation around the building as well. Can you send me the ppt you mentioned in your previous post? Thanks. Regards.
lalula2 is offline   Reply With Quote

Reply

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
Reynolds Stress model in CFX vs Fluent Tim CFX 1 October 7, 2009 07:19
FluentToFoam model thickness paka OpenFOAM Post-Processing 0 August 9, 2007 21:20
simulation results for k-w model and SST model Li CFX 7 June 29, 2007 05:19
Multiphase flow. Dispersed and free surface model Luis CFX 8 May 29, 2007 19:13
algebraic slip model with stirred suspension? Manuel Krause CFX 0 April 15, 2005 10:10


All times are GMT -4. The time now is 06:28.