[piprus]

Hi,

Yesterday, I faced a problem while using fluent3DMeshToFoam conversion tool. I believe the problem comes from its size, i.e. it's made of almost 120M pure hexahedral elements.

Just for clarity sake it's very simple 3D domain. It's a smooth pipe where a short inner cylidrical blunt body is coaxially located. What's important here is that, I have one inlet, one outlet and two walls, i.e. "wall_pls" - the one that creates the channel/pipe and the other one - "wall_plc" - that covers hollow space (the obstacle shape).

When I run fluent3DMeshToFoam, I get an error:

$ fluent3DMeshToFoam LES_r05_19.msh 
/*---------------------------------------------------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  5.0                                   |
|   \\  /    A nd           | Web:      www.OpenFOAM.org                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
Build  : 5.0
Exec   : fluent3DMeshToFoam LES_r05_19.msh
Date   : Apr 27 2021
Time   : 00:24:00
Host   : "workstation001"
PID    : 294780
I/O    : uncollated
Case   : /mnt/home/pprusinski/OF_cases/Conversion
nProcs : 1
fileModificationChecking : Monitoring run-time modified files using timeStampMaster (fileModificationSkew 10)
allowSystemOperations : Allowing user-supplied system call operations

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
Create time

Overriding OptimisationSwitches according to controlDict
    fileModificationSkew 0;

    maxMasterFileBufferSize 1e+09;

    maxThreadFileBufferSize 1e+09;

Dimension of grid: 3
Number of points: 119124502
Number of faces: 355043200
Number of cells: 117960000
PointGroup: 2 start: 0 end: 116798097.  Reading points...done.
PointGroup: 3 start: 116798098 end: 119124501.  Reading points...done.
FaceGroup: 1 start: 0 end: 352716799.  Reading uniform faces...done.
FaceGroup: 5 start: 352716800 end: 352777999.  Reading uniform faces...done.
FaceGroup: 6 start: 352778000 end: 352839199.  Reading uniform faces...done.
FaceGroup: 7 start: 352839200 end: 354159199.  Reading uniform faces...done.
FaceGroup: 8 start: 354159200 end: 355043199.  Reading uniform faces...done.
CellGroup: 4 start: 0 end: 117959999 type: 1
Zone: 1 name: interior-domain type: interior.  Reading zone data...done.
Zone: 4 name: domain type: fluid.  Reading zone data...done.
Zone: 5 name: inlet type: velocity-inlet.  Reading zone data...done.
Zone: 6 name: outlet type: pressure-outlet.  Reading zone data...done.
Zone: 7 name: wall_pls type: wall.  Reading zone data...done.
Zone: 8 name: wall_plc type: wall.  Reading zone data...done.

FINISHED LEXING

Creating patch 0 for zone: 5 name: inlet type: velocity-inlet
Creating patch 1 for zone: 6 name: outlet type: pressure-outlet
Creating patch 2 for zone: 7 name: wall_pls type: wall
Creating patch 3 for zone: 8 name: wall_plc type: wall
Creating cellZone 0 name: domain type: fluid
Creating faceZone 0 name: interior-domain type: interior
faceZone from Fluent indices: 0 to: 352716799 type: interior
patch 0 from Fluent indices: 352716800 to: 352777999 type: velocity-inlet
patch 1 from Fluent indices: 352778000 to: 352839199 type: pressure-outlet
patch 2 from Fluent indices: 352839200 to: 354159199 type: wall
patch 3 from Fluent indices: 354159200 to: 355043199 type: wall
new cannot satisfy memory request.
This does not necessarily mean you have run out of virtual memory.
It could be due to a stack violation caused by e.g. bad use of pointers or an out of date shared library
Aborted (core dumped)

As the memory is not a problem for sure, i.e. I did measure RAM consumption while performing procedure (BTW. my workstation has more than 750 GB RAM). I tried to use walk-around given here https://bugs.openfoam.org/view.php?id=1465, i.e. applying flag -ignoreFaceGroups. But again no luck:

$ fluent3DMeshToFoam -ignoreFaceGroups wall_plc LES_r05_19.msh 
/*---------------------------------------------------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  5.0                                   |
|   \\  /    A nd           | Web:      www.OpenFOAM.org                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
Build  : 5.0
Exec   : fluent3DMeshToFoam -ignoreFaceGroups wall_plc LES_r05_19.msh
Date   : Apr 27 2021
Time   : 12:19:15
Host   : "workstation001"
PID    : 305178
I/O    : uncollated
Case   : /mnt/home/pprusinski/OF_cases/Conversion
nProcs : 1
fileModificationChecking : Monitoring run-time modified files using timeStampMaster (fileModificationSkew 10)
allowSystemOperations : Allowing user-supplied system call operations

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //


--> FOAM FATAL IO ERROR: 
incorrect first token, expected <int> or '(', found on line 0 the word 'wall_plc'

file: IStringStream.sourceFile at line 0.

    From function Foam::Istream& Foam::operator>>(Foam::Istream&, Foam::HashTable<T, Key, Hash>&) [with T = Foam::nil; Key = Foam::word; Hash = Foam::string::hash]
    in file /mnt/opt/apps/slc6/openfoam/5.0-x86_64-gcc483/OpenFOAM-5.0/src/OpenFOAM/lnInclude/HashTableIO.C at line 203.

FOAM exiting

Does anybody know what am I doing wrong? What's wrong with this syntax:
fluent3DMeshToFoam -ignoreFaceGroups wall_plc LES_r05_19.msh

---------------------
Some extra mesh details based on statistics generated in Fluent:

117960000 hexahedral cells, zone  4, binary.
117960000 cell partition ids, zone  4, 2000 partitions, binary.
352716800 quadrilateral interior faces, zone  1, binary.
   61200 quadrilateral velocity-inlet faces, zone  5, binary.
   61200 quadrilateral pressure-outlet faces, zone  6, binary.
 1320000 quadrilateral wall faces, zone  7, binary.
  884000 quadrilateral wall faces, zone  8, binary.
119124502 nodes, binary.
119124502 node flags, binary.

*binary, as the Fluent setup is based on a compressed files... the setup for OF is made in ASCII mode yet.

[piprus]

As usually, posted question, found answers by myself.

When calling for FaceGroups one should refer to a list, even if it just one item. For these reason, one has to use parenthesis, another thing is that quotes are needed for the shell to not think that this was a sub-shell request. So to make it work it should look like this:

fluent3DMeshToFoam -ignoreFaceGroups '(wall_plc)' LES_r05_19.msh

For very big meshes (100M+), it is also recommended to switch writeFormat to ascii (controlDict) in order to avoid some further problems with structure of polyMesh/faces file, i.e. another parenthesis issue.