[NKever]

Hi Everyone,

I am approaching with what should be a pretty straight forward question, I think.

I want to make a geometry with a long and thin inlet area entering a rectangular area and then exiting into a long and thin outlet, as shown in geom.png.

This is how I went about it:

For the purposes of getting a structured mesh that could be refined in the center, I created two separate solids (whole geometry and central rectangular area) and partitioned them.

After creating my groups, I meshed and obtained something I was happy with testing. However, when I tried to convert it using ideasUnvToFoam, I got the following error:

/*---------------------------------------------------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  2112                                  |
|   \\  /    A nd           | Website:  www.openfoam.com                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
Build  : _d44c8318-20220111 OPENFOAM=2112 version=2112
Arch   : "LSB;label=32;scalar=64"
Exec   : ideasUnvToFoam sbend3Step.unv
Date   : Mar 16 2022
Time   : 14:15:05
Host   : nadeem-VirtualBox
PID    : 26974
I/O    : uncollated
Case   : /home/nadeem/openfoamOpenCFD/run/sbendCases/sbend3Step
nProcs : 1
trapFpe: Floating point exception trapping enabled (FOAM_SIGFPE).
fileModificationChecking : Monitoring run-time modified files using timeStampMaster (fileModificationSkew 5, maxFileModificationPolls 20)
allowSystemOperations : Allowing user-supplied system call operations

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

Processing tag:164
Starting reading units at line 3.
l:1
units:"  SI: Meter (newton)"
unitType:2
Unit factors:
    Length scale       : 1
    Force scale        : 1
    Temperature scale  : 1
    Temperature offset : 273.15


Processing tag:2420
Skipping tag 2420 on line 9
Skipping section at line 9.

Processing tag:2411
Starting reading points at line 20.
Read 6048 points.

Processing tag:2412
Starting reading cells at line 12119.
First occurrence of element type 11 for cell 1 at line 12120
First occurrence of element type 44 for cell 711 at line 14250
First occurrence of element type 115 for cell 6789 at line 26406
Read 2864 cells and 6078 boundary faces.

Processing tag:2467
Starting reading patches at line 32136.
For group 11 named frontAndBack trying to read 5760 patch face indices.
For group 12 named inlet trying to read 16 patch face indices.
For group 13 named outlet trying to read 16 patch face indices.
For group 14 named walls trying to read 318 patch face indices.

Of 6078 so-called boundary faces 32 belong to two cells and are therefore internal
Sorting boundary faces according to group (patch)
0: frontAndBack is faceZone
1: inlet is patch
2: outlet is patch
3: walls is faceZone

Constructing mesh with non-default patches of size:
    inlet	16
    outlet	16

--> FOAM Warning : 
    From Foam::polyMesh::polyMesh(const Foam::IOobject&, Foam::pointField&&, const cellShapeList&, const faceListList&, const wordList&, const wordList&, const Foam::word&, const Foam::word&, const wordList&, bool)
    in file meshes/polyMesh/polyMeshFromShapeMesh.C at line 646
    Found 6014 undefined faces in mesh; adding to default patch defaultFaces
Adding cell and face zones
 Face Zone walls 	318
ideasUnvToFoam: ideasUnvToFoam.C:1265: int main(int, char**): Assertion `noveau > -1' failed.
Aborted (core dumped)

I think the issue may be how salome treats the faces where the solids meet when I run the partition function. I found the following relevant post, but hopefully there's an easier solution than having to patch my ideasUnvToFoam file (which I tried and did not succeed in doing).

Post: ideasUnvToFoam with inner parts

I am open to any suggestions, all I would like is to have this be a structured mesh and ideally have a way for the central rectangular area be refined. I'm still a beginner at this stuff, so it's entirely possible I'm missing something obvious.

I have also included my study for reference at the following link:
https://easyupload.io/rtrw8b

This is meant to be a 2D case for openFoam.

Thanks for your help!