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

sHM and cyclicGgi

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

Reply
 
LinkBack Thread Tools Display Modes
Old   November 8, 2010, 11:08
Default
  #21
Member
 
Join Date: May 2010
Posts: 33
Rep Power: 7
FabOr is on a distinguished road
Hi Thomas,

thanks. the result looks nice. thats exactly what ive want. i hope i can transfer the setting on a mesh made by shm (different number of faces on the opposite sides)...

what steps did you take?
1) blockMesh
2) faceSet
3) setsToZones -noFlipMap
4) change boundary-file

best regards
FabOr is offline   Reply With Quote

Old   November 8, 2010, 16:48
Default
  #22
Member
 
Thomas Wolfanger
Join Date: Mar 2009
Location: South West Germany
Posts: 60
Rep Power: 8
anger is on a distinguished road
Quote:
Originally Posted by FabOr View Post
Hi Thomas,

thanks. the result looks nice. thats exactly what ive want. i hope i can transfer the setting on a mesh made by shm (different number of faces on the opposite sides)...

what steps did you take?
1) blockMesh
2) faceSet
3) setsToZones -noFlipMap
4) change boundary-file

best regards

Hello FabOr,

for the second step, I used setSet -batch system/setSetBatch (just for the sake of completeness, faceSet should also work (I think ) ), all other steps are ok.

Best regards,
-Thomas
anger is offline   Reply With Quote

Old   November 9, 2010, 04:19
Default
  #23
Member
 
Join Date: May 2010
Posts: 33
Rep Power: 7
FabOr is on a distinguished road
Hi Thomas,

it works also with shm-meshes

Thank you very much!

Best regards
FabOr is offline   Reply With Quote

Old   November 10, 2010, 11:20
Default
  #24
New Member
 
kalyan
Join Date: Oct 2010
Posts: 19
Rep Power: 6
hardykalyan is on a distinguished road
Hi Thomas,

Thank you very much for the case file and it helped me to understand ggi well.

Can you suggest me an idea of using the non-matching grids(think-cyclicGgi) and a rotating solid(ggi) together in the same case?
hardykalyan is offline   Reply With Quote

Old   November 15, 2010, 16:36
Default further explanation needed
  #25
Member
 
Thomas Wolfanger
Join Date: Mar 2009
Location: South West Germany
Posts: 60
Rep Power: 8
anger is on a distinguished road
Quote:
Originally Posted by hardykalyan View Post
Hi Thomas,

Thank you very much for the case file and it helped me to understand ggi well.

Can you suggest me an idea of using the non-matching grids(think-cyclicGgi) and a rotating solid(ggi) together in the same case?
Hello hardykalyan,

sorry, I don't understand what you mean, can you explain it furhter and/or supply a sketch?

Best regards,
-Thomas
anger is offline   Reply With Quote

Old   February 25, 2011, 10:17
Default
  #26
Member
 
Claudio
Join Date: Mar 2010
Posts: 57
Rep Power: 7
claco is on a distinguished road
Quote:
Originally Posted by anger View Post
Hi FabOr,

The link I mentioned above is
http://www.tfd.chalmers.se/~hani/kurser/OS_CFD/case_study_2010_OP.pdf
where you can find informations on setting up a ggi boundary for either cyclic or translational cases.
I think ggi (not cyclicGgi!) will work for your case. You could start by taking the mesh of a tutorial case (like channel395), change it to your needs and then introduce the ggi instead of the standard cyclic bc to get an idea of the correct setup. Be aware that ggi only works in 1.5-dev.

Best regards,
-Thomas

Dear Thomas,

I am using OF 1.5-dev (the last version released). I am simulating a blade of a radial pump.

I am using cyclicGgi patch, with the bridgeOverlap=false option. But when I run the MRFSimpleFoam solver, the message "Found uncovered faces for GGI interface Per1/Per2 while the bridgeOverlap option is not set in the boundary file." appears.

I personally think that i would have to set this option true, because the cyclic patches do not overlap with themselves.

What can You kindly suggest me to this purpose?

Best regards,

Claudio



However, when I run
claco is offline   Reply With Quote

Old   February 26, 2011, 06:36
Default
  #27
Member
 
Thomas Wolfanger
Join Date: Mar 2009
Location: South West Germany
Posts: 60
Rep Power: 8
anger is on a distinguished road
Hi Claudio,

meanwhile there is OF-1.6-ext which is also capable of GGI interpolation and is the successor of 1.5-dev, so the things stated above are a little bit outdated.
Regarding your problem, if the patches do not geometrically match, then set bridgeOverlap to true. However, for a radial pump, I'm not sure why they shouldn't do so. If you created your mesh with sHM, than there might be problems because sHM edges are not following strictly the stl geometry, and if this was the case, you'd have to be clear about the effects of setting bridgeOverlap to true to get the simulation running.

Regards,
-Thomas
anger is offline   Reply With Quote

Old   February 8, 2012, 15:58
Default
  #28
Member
 
Aqua
Join Date: Oct 2011
Posts: 96
Rep Power: 5
aqua is on a distinguished road
Quote:
Originally Posted by anger View Post
Hi FabOr,

if the second file was your actual one, following things are strange:
- there is only one cyclicGgi entry; there should be two (for example "cyclicY")
- not all subentries are filled in; you have to define the correct shadow patch (if the above was correct, the shadow patch entry in "cyclicX" should be "cyclicY")
- your mesh has to have the corresponding face zones which you also have to define for example via faceSet
- take care of the rotation angle; fill in the correct value for your case.

I'll have a look whether I can find a very simple test case to demonstrate the setup. Meanwhile, you could search the net (I remember that I derived my setup from a presentation of a member of the turbomachinery SIG, but I don't remember the name...)

Regards,
-Thomas
Hello Thomas,
Does rotationAngle mean the angle between the two patches which are setted as cyclicGgi? How to decide the angle is positive or negative? Because in the 1.6-ext tutorial, the case "turboPassangeRotating", the rotationAngle is 30 degree for one patch and -30 degree for the couple patch..I don't know why...

Thank you so much!

Aqua
aqua is offline   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



All times are GMT -4. The time now is 00:43.