CCM+ Mesh Conversion
 

Hello Foamers,

does any one know, how can I convert a Starccm+ file (.sim) to openFoam, so that OpenFOAM can read the converted mesh of ccm+?

for any help I will be grateful,

greetings,

Mizo

Greetings Mizo,

You'll need two things:

1. To export just the mesh in ".ccm" format.
2. Then to build and use ccm26ToFoam: http://openfoamwiki.net/index.php/Ccm26ToFoam

Best regards,
Bruno

Thank u Bruno :)

Hi Bruno,

am trying to solve a case (unsteady -PISO) but i cant get the convergence.
delta T : 0.0001
my mesh is 120 mil. cells
do u have a solution of the (unconverged function walls) with a very very big courant number? like his:

Time = 0.0281
Courant Number mean: 200.98646479 max: 483002494258
smoothSolver: Solving for nuTilda, Initial residual = 0.776899796969, Final residual = 9.35320630902e-07, No Iterations 204
bounding nuTilda, min: -148081.560032 max: 2627072.04411 average: 8.44973042553
6059 faces with unconverged wall functions on patch Boden
189 faces with unconverged wall functions on patch belt
925 faces with unconverged wall functions on patch Rad_VL
30 faces with unconverged wall functions on patch Rad_VR
16 faces with unconverged wall functions on patch Rad_HL
19 faces with unconverged wall functions on patch Rad_HR
73866 faces with unconverged wall functions on patch Underbody
16040 faces with unconverged wall functions on patch Front_Tires
1390 faces with unconverged wall functions on patch Rear_Tires
2934 faces with unconverged wall functions on patch Bohr_VA
525 faces with unconverged wall functions on patch Suspension
9608 faces with unconverged wall functions on patch Power
81840 faces with unconverged wall functions on patch Wrapp Exterior10
20109 faces with unconverged wall functions on patch Package
884 faces with unconverged wall functions on patch System
146 faces with unconverged wall functions on patch Fine_Exterior
5457 faces with unconverged wall functions on patch Exterior
3923 faces with unconverged wall functions on patch Wand_922
4 faces with unconverged wall functions on patch Wrapped_Surface_C218_Komplett_Gap_Closure_Faces
smoothSolver: Solving for Ux, Initial residual = 0.531876492884, Final residual = 9.08285502316e-07, No Iterations 64
smoothSolver: Solving for Uy, Initial residual = 0.497932997079, Final residual = 9.22073404821e-07, No Iterations 59
smoothSolver: Solving for Uz, Initial residual = 0.333758685155, Final residual = 9.08170020727e-07, No Iterations 46
GAMG: Solving for p, Initial residual = 6.15720458897e-09, Final residual = 3.66424545854e+22, No Iterations 1000
GAMG: Solving for p, Initial residual = 4.59788012312e-05, Final residual = 2.88958539135e+28, No Iterations 1000
GAMG: Solving for p, Initial residual = 4.59784422852e-05, Final residual = 2.88958622398e+28, No Iterations 1000
time step continuity errors : sum local = 3.42521516445e+96, global = 6.51568390001e+91, cumulative = 6.51568390001e+91
GAMG: Solving for p, Initial residual = 5.43773101144e-05, Final residual = 2.2335068526e+28, No Iterations 1000
[192] #0 Foam::error::printStack(Foam::Ostream&)--------------------------------------------------------------------------
An MPI process has executed an operation involving a call to the
"fork()" system call to create a child process. Open MPI is currently
operating in a condition that could result in memory corruption or
other system errors; your MPI job may hang, crash, or produce silent
data corruption. The use of fork() (or system() or other calls that
create child processes) is strongly discouraged.
The process that invoked fork was:
Local host: aero9134 (PID 12855)
MPI_COMM_WORLD rank: 192
If you are *absolutely sure* that your application will successfully
and correctly survive a call to fork(), you may disable this warning
by setting the mpi_warn_on_fork MCA parameter to 0.
--------------------------------------------------------------------------
addr2line failed
[192] #1 Foam::sigFpe::sigFpeHandler(int) addr2line failed
[192] #2 Uninterpreted: /lib64/libc.so.6 addr2line failed
[192] #3 Foam::GAMGSolver::scalingFactor(Foam::Field<double >&, Foam::Field<double> const&, Foam::Field<double> const&, Foam::Field<double> const&) const addr2line failed
[192] #4 Foam::GAMGSolver::Vcycle(Foam::PtrList<Foam::lduMa trix::smoother> const&, Foam::Field<double>&, Foam::Field<double> const&, Foam::Field<double>&, Foam::Field<double>&, Foam::Field<double>&, Foam::PtrList<Foam::Field<double> >&, Foam::PtrList<Foam::Field<double> >&, unsigned char) const addr2line failed
[192] #5 Foam::GAMGSolver::solve(Foam::Field<double>&, Foam::Field<double> const&, unsigned char) const addr2line failed
[192] #6 Foam::fvMatrix<double>::solve(Foam::dictionary const&) addr2line failed
[192] #7 Uninterpreted: pisoFoam
[192] #8 __libc_start_main addr2line failed
[192] #9 Foam::regIOobject::writeObject(Foam::IOstream::str eamFormat, Foam::IOstream::versionNumber, Foam::IOstream::compressionType) const
[134:12855] *** Process received signal ***
[134:12855] Signal: Floating point exception (8)
[134:12855] Signal code: (-6)
[134:12855] Failing at address: 0xc6af00003237
[134:12855] [ 0] /lib64/libc.so.6 [0x2b5365441300]
[134:12855] [ 1] /lib64/libc.so.6(gsignal+0x35) [0x2b5365441295]
[134:12855] [ 2] /lib64/libc.so.6 [0x2b5365441300]
2.1.2/lib/linux64GccDPOpt/libFOAM.so(_ZNK4Foam10GAMGSolver13scalingFactorERN S_5FieldIdEERKS2_S5_S5_+0x12b) [0x2b536459c43b]
(_ZNK4Foam10GAMGSolver6VcycleERKNS_7PtrListINS_9ld uMatrix8smootherEEERNS_5FieldIdEERKS8_S9_S9_S9_RNS 1_IS8_EESD_h+0x137f) [0x2b536459f32f]
(_ZNK4Foam10GAMGSolver5solveERNS_5FieldIdEERKS2_h+ 0x4bf) [0x2b536459ffaf]
2.1.2/lib/linux64GccDPOpt/libfiniteVolume.so(_ZN4Foam8fvMatrixIdE5solveERKNS _10dictionaryE+0x140) [0x2b536351b450]
[134:12855] [ 7] oodles [0x4215ef]
[134:12855] [ 8] /lib64/libc.so.6(__libc_start_main+0xf4) [0x2b536542e9c4]
[134:12855] [ 9] oodles(_ZNK4Foam11regIOobject11writeObjectENS_8IOs tream12streamFormatENS1_13versionNumberENS1_15comp ressionTypeE+0xd1) [0x41cd29]
[134:12855] *** End of error message ***
--------------------------------------------------------------------------

thank u in advance

Mizo

What checkMesh say??

Hell Tuominen,

The Mesh is Ok, but only the Skewness is not good (***Max Skewness=17)
I actually had a Case with (***Max Skew =22) and the solution was fine converged but the cells number was bretty smaller than now

.csv file format to import in Open foam for meshing
 

Hai OF friends,

I am David,My interest is flapping & flexible wing MAV.

Generally for meshing we need cad files in .stl /.obj format for import. For my problem instead of having .stl/.obj format I have matlab m file format. I don't know how to import m file in open foam for meshing. kindly give your suggestions & feedback.


Many Thanks,
david

Hi David,

I think you have to convert it to Nastran file at first (maybe with catia) then import the file into ANSA program and then output as STL file.

best regards

Thanks for reply Mizo,

Its not like geometry, I mark the points on my wing by using camera to capture the wing movement and extract the xyz coordinates of my flapping flexible wing by using DLVT5 matlab code.The output i got is .csv format, from that I plot the data in matlab for seeing the replication of my wing. please see my post Title:Mosquito Analysis in Open Foam for your reference.

If its one frame, what ever you are telling OK, because each frame its gives geometry from that to make STL format, but I don't want that one, basically its quasi steady analysis. I want to do unsteady.

Here is totally 10 frame if i plot the data in matlab to make loop and its continuous flapping like insect.

I have only matlab file I don't how to incorporate with open foam for meshing?

please give me your suggestions about my queries.


Many thanks,
david

Hi David,

as I know, it's only possible for STL/Nastran fils to be simulated with OF.
U have o convert your matlab file .csv to one of these formats.
as workaround you can convert your file to Binary then import it to ansa to get stl/ nastran in (ASCII)

Thanks Mizo for your quick reply and kind information,

I try my best.


Many thanks,
David

Hi Bruno,

Could you please tell me how can I convert the Whole FOAM Case (with MRF and porourse Media) to fluent, I used the utility (foamMeshToFluent) but the MRF & porouse were not between the BC of the new Fluent mesh

thanx alot in advance

best regards

Mizo

Hi Mizo, may I ask you if you're using a polyhedral or a trimmer mesh from star? My transient Piso-simulations always chrash with a trimmer-mesh. After looking in the comments of the source code of ccm226ToFoam I came to the conclusion, that only Polyhedral meshes are supported. Am I right, pls someone correct me if not :)?

Best regards,
Za-ck

Hi Za-Ck :)

thank you for your reply, I will tell you the problem, which I had:
The problem was that I specified the first layer thickniss of the boundary layer with too small value
and I can tell you now (very sure) that the solution will be absolutly not converged if you have very small cells (in the region of the boundary layer )

Mizo

Greetings to all!

@Mizo:
When converting between mesh types, it's very likely to not be able to convert every feature of the original mesh. In this case, foamMeshToFluent was not designed to export "cellZones" that OpenFOAM uses, which is why they aren't available in the resulting file.

There was one vague possible hack, where the field "cellToRegion" could be converted to a field as fluent data (foamDataToFluent needs a dictionary: https://github.com/OpenFOAM/OpenFOAM...taToFluentDict ), but the problem would then be how you would convert this field into the porous zone in the target CFD application.

Best regards,
Bruno

many thanks Bruno,

you are the Master of CFD :)
I will try and tell you the results :)

best regards

Mizo

Hi All!

I am a new member in this forum. Nice to read all the post which is very helpful.

I have a problem, now I am generating a mesh from a stl file, but I do not know how to put the boundary condition. I tried to use Star CCM+ and named some boundary condition there, but when I tried to convert it to OpenFoaam using ccm26toFoam, it only detected one boundary, which is the wall, while the other patches were not detected. Do you have any idea to solve this? or can you suggest me on how to put the boundary condition from a stl data? Thanks and have a nice day.

Best regards,
Abiel

Greetings Abiel and welcome to the forum!

There are two possible answers to your question:

1. Check the file "constant/polyMesh/boundary" to confirm if there is really only one boundary condition. I say this because you might be confusing the boundary conditions on the fields, versus the ones on the mesh. In other words, ccm26ToFoam only generates the BCs for the mesh, not for the fields.
2. The other possibility is that you did not select the patches in the export list, while exporting in Star-CCM+ to ".ccm".

Best regards,
Bruno