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

pimpleDyMfoam simulation keeps blowing up

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

Like Tree14Likes

Reply
 
LinkBack Thread Tools Display Modes
Old   June 6, 2013, 03:56
Default
  #61
Member
 
Andrew Glassby
Join Date: Sep 2009
Posts: 65
Rep Power: 7
ADGlassby is on a distinguished road
Thanks for that! I have executed that command and noted that I have two regions in my constant/polyMesh/cellZones file.

With AMI I have noticed that the dynamicMeshdict requires a faceZone. I tried to create this using setSet with the following sequence:

faceSet innerFace new patchToFace AMIMoving <that's my moving zone's face>
faceZoneSet innerFace new setsToFaceZone innerFace region1 <I think this is my inner region>

Out of interest is there a way of finding out which region relates to which of my two merged meshes? I did try region0 too!!

rerunning pimpleDymFOAM, now, just reproduces the rotation of the whole model that I have been fighting with for so long.

Any other suggestions? I can zip up my model if that might help? It's a bit convoluted though since I am running snappyHexMesh(Castellated) / flattehMesh / Extrude / snappyHexMesh(Snap) on each mesh before merging them.

Kindest Regards

Andrew
ADGlassby is offline   Reply With Quote

Old   June 6, 2013, 06:17
Default
  #62
Senior Member
 
linnemann's Avatar
 
Niels Nielsen
Join Date: Mar 2009
Location: NJ - Denmark
Posts: 445
Rep Power: 14
linnemann will become famous soon enough
Cant you just zip the final case where it rotates the whole mesh.

Use dropbox, Gdrive or something else if its too big for CFD-online
__________________
Linnemann

PS. I do not do personal support, so please post in the forums.
linnemann is offline   Reply With Quote

Old   June 6, 2013, 08:05
Default
  #63
Member
 
Andrew Glassby
Join Date: Sep 2009
Posts: 65
Rep Power: 7
ADGlassby is on a distinguished road
Hi.... Here is the dropbox link. I've tried to tidy up the directory structure a bit and put notes in the shell script files.
https://dl.dropboxusercontent.com/u/...eTestAMI2D.zip

Best Regards
Andrew
ADGlassby is offline   Reply With Quote

Old   June 6, 2013, 09:11
Default
  #64
Senior Member
 
linnemann's Avatar
 
Niels Nielsen
Join Date: Mar 2009
Location: NJ - Denmark
Posts: 445
Rep Power: 14
linnemann will become famous soon enough
Hi cant we just get the final case.

The shell scripts does not work properly.

Best
__________________
Linnemann

PS. I do not do personal support, so please post in the forums.
linnemann is offline   Reply With Quote

Old   June 6, 2013, 10:40
Default
  #65
Member
 
Andrew Glassby
Join Date: Sep 2009
Posts: 65
Rep Power: 7
ADGlassby is on a distinguished road
Duh, sorry, didn't read your last entry fully..... this link gives the model at the last step after the merge and splitMeshRegions.

https://dl.dropboxusercontent.com/u/...innemanAMI.zip

The Master directory is AMI

Regards

Andrew
ADGlassby is offline   Reply With Quote

Old   June 6, 2013, 10:58
Default
  #66
Member
 
Andrew Glassby
Join Date: Sep 2009
Posts: 65
Rep Power: 7
ADGlassby is on a distinguished road
Oh... The shell scripts probably didn't work right because I'm running OF on Mac OS X.... I think the grep statements are formed differently to linux.

Andrew
ADGlassby is offline   Reply With Quote

Old   June 7, 2013, 05:16
Default
  #67
Senior Member
 
linnemann's Avatar
 
Niels Nielsen
Join Date: Mar 2009
Location: NJ - Denmark
Posts: 445
Rep Power: 14
linnemann will become famous soon enough
Hi

Just change this in the dynamicMeshDict

Code:
solidBodyMotionFvMeshCoeffs
{
    cellZone        region0;

    solidBodyMotionFunction  rotatingMotion;
    rotatingMotionCoeffs
    {
        CofG        (0 0 0);
        radialVelocity (0 0 360); // deg/s
    }
}
Everything works fine

https://docs.google.com/file/d/0Bxal...it?usp=sharing
__________________
Linnemann

PS. I do not do personal support, so please post in the forums.
linnemann is offline   Reply With Quote

Old   June 7, 2013, 05:38
Default
  #68
Member
 
Andrew Glassby
Join Date: Sep 2009
Posts: 65
Rep Power: 7
ADGlassby is on a distinguished road
Thank you so much for your help....... although it does make me feel incredibly thick! I think I got fixated on the faceZone entry in dynamicMeshDict and didn't look into what the possibilities were!

Out of interest though why was my faceZone method not working? In my setSet step (not in the model I shared late yesterday but in the setBatch file in the original share) I thought I was making a faceZone which incorporated the cellZone region0 and the AMIMoving face.... obviously this was wrong but I'd like to try to understand what was wrong about it? Is this something you could advise me on?

Once again, thanks you so much for your help and patience!

Kindest Regards

Andrew
ADGlassby is offline   Reply With Quote

Old   June 18, 2013, 06:25
Default
  #69
Member
 
Andrew Glassby
Join Date: Sep 2009
Posts: 65
Rep Power: 7
ADGlassby is on a distinguished road
I'm trying to take a slightly different track with my model now and I'm wondering how best to achieve the result. I've been experimenting with a basic mesh (essentially cavity) and creating an inner and outer mesh using setSet. I have been able to create cellSets for the inner and outer regions but if I want to rotate the inner cellset what would be the best way to do this?

The basic mesh has NO internal feature, like in the cavity tutorial, so I am building internal features like the cellSets. I'm trying to rotate the cells in an AMI / dynamicMesh fashion like my last experimentation so I need to create two patches for the AMI faces. should this be based on createBaffles / mergeOrSplitMeshes -split or it there a more appropriate method like splitMeshRegions?

I'm doing this in order to reduce the amount of time spent meshing for future models since sHM/flatten/extrude/sHM for each region then merging and splitting the mesh seems quite involved if I can sHM/flatten/Extrude/sHM once and then introduce the internal AMI features I require. Also I don't seem to be able to get the much closer distances between the two meshes that I would like using the merge method.

I have tried creating a faceZone based on the inner cellSet then creating baffles but this doesn't seem to work, if I try to use moveDynamicMesh it just fails with a segFault (I'm using MacOSX so it's perhaps not as well manner as in Linux!)

I would welcome anyone's suggestions and guidance on this.

regards

Andrew
ADGlassby is offline   Reply With Quote

Old   December 11, 2013, 11:01
Default
  #70
Senior Member
 
sivakumar selvaraju
Join Date: Mar 2009
Location: Cape Town - South Africa
Posts: 186
Rep Power: 8
sivakumar is on a distinguished road
Send a message via Skype™ to sivakumar
Hi all,
I have a basic problem to setup a case for pimpleDyMFoam solver,
I got some idea from this post, still I am not clear.

In my case I have 3 domain Inlet Volume, fan Volume, outlet volume.
you can imagine the case is just a pipe, sub divided in to 3 volume (see attached Fig).
The middle one is suppose to rotate. So far I am using MRF its going fine.

Now I want to use pimpleDyMFoam, I dont know how to treat the in between faces.
This is going to be my first try please help and correct me,

steps what I understood from the previous post is,

1) I need to split the domain in to three.
As long as i am going to use sliding mesh, so the mesh no need to be conformal I think.

2) Then I will have three .msh files

I have few questions,

before exporting the mesh, while giving BC in Gambit what BC, should I use for the faces (interface? internal?)

where I need to place this three .msh file? all in one folder? or separately?

after converting this mesh, there will be three constant folder.

Do I need to edit anything before merging this mesh? if so where and what I need to edit.

Please help me to go further.

Thanks,
Sivakumar
Attached Files
File Type: pdf fig.pdf (22.3 KB, 15 views)
sivakumar is offline   Reply With Quote

Old   December 11, 2013, 15:23
Default
  #71
Senior Member
 
calim_cfd's Avatar
 
mauricio
Join Date: Jun 2011
Posts: 136
Rep Power: 8
calim_cfd is on a distinguished road
Quote:
Originally Posted by sivakumar View Post
Hi all,
I have a basic problem to setup a case for pimpleDyMFoam solver,
I got some idea from this post, still I am not clear.

In my case I have 3 domain Inlet Volume, fan Volume, outlet volume.
you can imagine the case is just a pipe, sub divided in to 3 volume (see attached Fig).
The middle one is suppose to rotate. So far I am using MRF its going fine.

Now I want to use pimpleDyMFoam, I dont know how to treat the in between faces.
This is going to be my first try please help and correct me,

steps what I understood from the previous post is,

1) I need to split the domain in to three.
As long as i am going to use sliding mesh, so the mesh no need to be conformal I think.

2) Then I will have three .msh files

I have few questions,

before exporting the mesh, while giving BC in Gambit what BC, should I use for the faces (interface? internal?)

where I need to place this three .msh file? all in one folder? or separately?

after converting this mesh, there will be three constant folder.

Do I need to edit anything before merging this mesh? if so where and what I need to edit.

Please help me to go further.

Thanks,
Sivakumar
hi
first of all MRF is usually used in steadystate cases. Pimpledymfoam is for transient cases, or at least transient solution cases. For the dynamic case where the domain does indeed rotate, you have to set the region(s) which rotates. the interfaces you should set as AMI so that the solver can handle non-conformal patches that happen in rotating regions.

but if u have a steadystate case with a cyclic domain with a mrf region then you should use other solvers, like the MRFsth.

try to figure out what u need first, is your case transient or ss? and then u go from there..

gl
__________________
Best Regards
/calim

"Elune will grant us the strength"
calim_cfd is offline   Reply With Quote

Old   December 11, 2013, 15:47
Default
  #72
Senior Member
 
sivakumar selvaraju
Join Date: Mar 2009
Location: Cape Town - South Africa
Posts: 186
Rep Power: 8
sivakumar is on a distinguished road
Send a message via Skype™ to sivakumar
Hi Calim , thanks for your reply, I don't know which question is forced you to answer like this.
  • After checking all my needs and possibilities, I have decided to use that solves.

Siva

Last edited by sivakumar; December 12, 2013 at 03:40.
sivakumar is offline   Reply With Quote

Old   December 12, 2013, 04:07
Default
  #73
Senior Member
 
sivakumar selvaraju
Join Date: Mar 2009
Location: Cape Town - South Africa
Posts: 186
Rep Power: 8
sivakumar is on a distinguished road
Send a message via Skype™ to sivakumar
Hi There,
I tried and followed the steps mentioned in this thread, I dont know which step I am missing.

Please help me to sort out the problem.

Here is the step which I followed,

1) I have divided my domain in to 3 volume, each volume has its unique faces, then non conformal has been generated. (4 interface are defined AMI_1, AMI_2 ......)

2) fluent3DMeshToFoam

3) I have modified the AMI boundaries under case/constant/boundary ( as jiejie explained in his post)

I am not sure what are the steps I need to perform more.

While executing checkMesh I am getting the following error,

Code:
Create time

Create polyMesh for time = 0

Time = 0

Mesh stats
    points:           2959944
    faces:            8672812
    internal faces:   8468870
    cells:            2856947
    boundary patches: 20
    point zones:      0
    face zones:       1
    cell zones:       2

Overall number of cells of each type:
    hexahedra:     2856947
    prisms:        0
    wedges:        0
    pyramids:      0
    tet wedges:    0
    tetrahedra:    0
    polyhedra:     0

Checking topology...
 ****Problem with boundary patch 3 named top0 of type wall. The patch should start on face no 8547530 and the patch specifies 8554881.
Possibly consecutive patches have this same problem. Suppressing future warnings.
 ***Boundary definition is in error.
    Cell to face addressing OK.
    Point usage OK.
    Upper triangular ordering OK.
    Face vertices OK.
   *Number of regions: 3
    The mesh has multiple regions which are not connected by any face.
  <<Writing region information to "0/cellToRegion"

Checking patch topology for multiply connected surfaces ...
    Patch               Faces    Points   Surface topology                  
    top2                37088    37653    ok (non-closed singly connected)  
    outlet              4484     4620     ok (non-closed singly connected)  
    center1             37088    37653    ok (non-closed singly connected)  
    top0                3965     4092     ok (non-closed singly connected)  
    center0             3965     4092     ok (non-closed singly connected)  
    inlet               2867     2976     ok (non-closed singly connected)  
    top1                8040     8268     ok (non-closed singly connected)  
    fan                 15720    15948    ok (non-closed singly connected)  
    ILR0                3055     3168     ok (non-closed singly connected)  
    ILR1                3055     3168     ok (non-closed singly connected)  
    OLR0                28792    29340    ok (non-closed singly connected)  
    OLR1                28792    29340    ok (non-closed singly connected)  
    CLR0                1800     1891     ok (non-closed singly connected)  
    CLR1                1800     1891     ok (non-closed singly connected)  
    FCLR0               1800     1891     ok (non-closed singly connected)  
    FCLR1               1800     1891     ok (non-closed singly connected)  
    AMI_1               2867     2976     ok (non-closed singly connected)  
    AMI_2               6000     6161     ok (non-closed singly connected)  
    AMI_3               6480     6649     ok (non-closed singly connected)  
    AMI_4               4484     4620     ok (non-closed singly connected)  

Checking geometry...
    Overall domain bounding box (0.239348 -0.371369 -0.75) (0.771515 0.354013 4)
    Mesh (non-empty, non-wedge) directions (1 1 1)
    Mesh (non-empty) directions (1 1 1)
    Boundary openness (3.92584e-14 6.56918e-14 -3.07888e-17) OK.
    Max cell openness = 3.36913e-16 OK.
    Max aspect ratio = 26.3734 OK.
    Minumum face area = 4.20635e-07. Maximum face area = 0.000104506.  Face area magnitudes OK.
    Min volume = 3.36453e-09. Max volume = 1.02511e-06.  Total volume = 0.931774.  Cell volumes OK.
    Mesh non-orthogonality Max: 59.4945 average: 11.6305
    Non-orthogonality check OK.
    Face pyramids OK.
    Max skewness = 1.5012 OK.
    Coupled point location match (average 5.3341e-12) OK.

Mesh OK.

End
Please give me some suggestions.

Thanks,
Siva

Last edited by wyldckat; December 30, 2013 at 11:03. Reason: Added [CODE][/CODE]
sivakumar is offline   Reply With Quote

Old   December 30, 2013, 11:20
Default
  #74
Super Moderator
 
Bruno Santos
Join Date: Mar 2009
Location: Lisbon, Portugal
Posts: 8,258
Blog Entries: 34
Rep Power: 84
wyldckat is just really nicewyldckat is just really nicewyldckat is just really nicewyldckat is just really nice
Greetings to all!

@Siva: I see that you have gotten some answers to your questions here: pimpleDyMFoam diverging

So I have no idea if you still are having problems with this.
If you are still having problems with this, I suggest that you create a simplified version of a case conceptually similar to yours, so that you can share it with us. That way it'll be easier to help you.

Because from the error message given by checkMesh, all I can figure out is that something went wrong in your editing of the file "boundary".

Best regards,
Bruno
wyldckat 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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Solar Radiation in OpenFOAM plainstyle OpenFOAM Running, Solving & CFD 15 July 8, 2014 04:43
Simulation of a complex wing in solidworks flow simulation niels1900 FloEFD, FloWorks & FloTHERM 6 April 20, 2011 10:44
pimpleDyMFoam stability problems cnsidero OpenFOAM Running, Solving & CFD 3 January 29, 2011 13:36
Continuous vs interrupted simulation sega OpenFOAM Running, Solving & CFD 4 November 3, 2008 15:29
strange simulation error Ralf Schmidt FLUENT 2 May 4, 2007 13:02


All times are GMT -4. The time now is 11:45.