CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > OpenFOAM > OpenFOAM Running, Solving & CFD

conflict between boundary and blockMeshDict?

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   January 22, 2013, 02:23
Default conflict between boundary and blockMeshDict?
  #1
Senior Member
 
immortality's Avatar
 
Ehsan
Join Date: Oct 2012
Location: Iran
Posts: 2,208
Rep Power: 27
immortality is on a distinguished road
a question!if i set a face to patch in boundary file.then at blockMeshDict i set its U to a value and p and T to zeroGradient(like a moving wall as in cavity)
Does it produce any conflict?then OF assumes it patch(fluid)or wall(solid)?
How about reciprocal of it.mean wall in boundary but patch in blockMeshDict?
Thanks.
immortality is offline   Reply With Quote

Old   January 22, 2013, 05:24
Default
  #2
ngj
Senior Member
 
Niels Gjoel Jacobsen
Join Date: Mar 2009
Location: Copenhagen, Denmark
Posts: 1,903
Rep Power: 37
ngj will become famous soon enoughngj will become famous soon enough
Hi Ehsan,

I believe you are a bit confused about the procedure. You create a blockMeshDict, which in turn writes in the file "boundary". You do not specify the actual boundary conditions for e.g. U, T or p in either of these. All you specify in blockMeshDict is whether the patch is a "patch", "wall", "cyclic", "empty", etc.

Furthermore, the boundary file is product of running blockMesh (acting on blockMeshDict), so the definitions in blockMeshDict and boundary should match.

To my knowledge the "wall" definition is used in e.g. wall functions for turbulence models, where it is only those boundary patches, which are defined as "wall", where the turbulent quantities are altered.

Kind regards

Niels
ngj is offline   Reply With Quote

Old   January 22, 2013, 07:50
Default
  #3
Senior Member
 
immortality's Avatar
 
Ehsan
Join Date: Oct 2012
Location: Iran
Posts: 2,208
Rep Power: 27
immortality is on a distinguished road
thanks.i remembered the procedure.now i correct my written :in blockMeshDict I set a face to patch but this face is changing from fluid inflow/outflow to wall and vice versa whan I use groovyBC for that.it shows an printstack error when its at the middle of wall duration.when i used it with laminar(without wall function)this error occured again.
is it pssible that patch and wall are different at their instinct basically?and when i use patch expression in blockMeshDict it assumes a fluid flow at the face and is permeable although we want wall?
are there some parts at compressible code that distinguish between wall and patch inherently?
someone at this forum told me to use createPatch utility.can I use that by groovyBC?if yes how it works?!
thanks alot for reading and attention.
immortality is offline   Reply With Quote

Old   January 22, 2013, 08:06
Default
  #4
ngj
Senior Member
 
Niels Gjoel Jacobsen
Join Date: Mar 2009
Location: Copenhagen, Denmark
Posts: 1,903
Rep Power: 37
ngj will become famous soon enoughngj will become famous soon enough
I do not have any knowledge about those part of the code.

Good luck,

Niels
ngj is offline   Reply With Quote

Old   January 22, 2013, 08:11
Default
  #5
Senior Member
 
immortality's Avatar
 
Ehsan
Join Date: Oct 2012
Location: Iran
Posts: 2,208
Rep Power: 27
immortality is on a distinguished road
can it cause an error in your opinion?
immortality 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
ribbed channel / simpleFoam / boundary conditions beeo OpenFOAM Pre-Processing 20 July 17, 2013 09:39
precedence of boundary file over blockMeshDict bfiedler OpenFOAM 2 January 22, 2013 11:52
BlockMeshDict for a Pipe sen.1986 OpenFOAM 1 March 19, 2012 16:41
[blockMesh] BlockMesh number internal faces and boundary ynos OpenFOAM Meshing & Mesh Conversion 6 December 13, 2011 06:36
Boundary Conditions for internal faces in 3D interFoam unikrsn OpenFOAM 9 September 27, 2011 13:09


All times are GMT -4. The time now is 22:47.