[slayengine]

Hi Community,
I'm new to this forum and didn't want to ask for your help, cause there are so many threads having almost similar issues.
But this one is special, so now it's definitely time to ask.



Introduction
My main goal is to simulate a laminar, incompressible flow of resin through a very little cell (20x15mm).
Pic1


Within the cell (cavity) there are rovings. These are consideres as walls with zero porosity.
Pic2



Structure
I'm having the following structure in Hypermesh before export to OpenFoam.
-----------------------
inlet (type face, pic 1: green face)
outlet (type face, pic 1: bright green face)
walls (type face, in pic 1+2: red cavity + colored rovings)

fluid (type solid)
-----------------------
First of all, is this structure correct? The fluid of type solids fills out the holes (empty space) btw. the rovings in the internal field.
Hypermesh doesn't complain about that setting. No error at all!



Setting
-simpleFoam algorithm
-laminar, incompressible
-Boundaries: Inlet 2bar, Outlet 0bar; velocities not given - zeroGradient



Error
checkMesh -allTopology log

/*---------------------------------------------------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  4.x                                   |
|   \\  /    A nd           | Web:      www.OpenFOAM.org                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
Build  : 4.x-acc2a7707ea6
Exec   : checkMesh -allTopology
Time   : 22:20:46
Host   : "uc1n262.localdomain"
PID    : 29287
nProcs : 1
sigFpe : Enabling floating point exception trapping (FOAM_SIGFPE).
fileModificationChecking : Monitoring run-time modified files using timeStampMaster
allowSystemOperations : Allowing user-supplied system call operations

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

Create polyMesh for time = 0

Enabling all (cell, face, edge, point) topology checks.

Time = 0

Mesh stats
    points:           2522342
    faces:            6630654
    internal faces:   5684580
    cells:            2052539
    faces per cell:   6
    boundary patches: 3
    point zones:      0
    face zones:       1
    cell zones:       1

Overall number of cells of each type:
    hexahedra:     2052539
    prisms:        0
    wedges:        0
    pyramids:      0
    tet wedges:    0
    tetrahedra:    0
    polyhedra:     0

Checking topology...
    Boundary definition OK.
    Cell to face addressing OK.
    Point usage OK.
    Upper triangular ordering OK.
    Face vertices OK.
    Topological cell zip-up check OK.
    Face-face connectivity OK.
  <<Writing 9737 cells with zero or one non-boundary face to set oneInternalFaceCells
  <<Writing 25090 cells with two non-boundary faces to set twoInternalFacesCells
   *Number of regions: 2670
    The mesh has multiple regions which are not connected by any face.
  <<Writing region information to "0/cellToRegion"
  <<Writing region 0 (point connected) with 2047241 cells to cellSet region0
  <<Writing region 1 (point connected) with 3 cells to cellSet region1
  <<Writing region 2 (point connected) with 2 cells to cellSet region2
  <<Writing region 3 (point connected) with 11 cells to cellSet region3
  <<Writing region 4 (point connected) with 1 cells to cellSet region4
  <<Writing region 5 (fully disconnected) with 2 cells to cellSet region5
  <<Writing region 6 (fully disconnected) with 2 cells to cellSet region6
[...] till last region:
  <<Writing region 2669 (point connected) with 27 cells to cellSet region2669

Checking patch topology for multiply connected surfaces...
    Patch               Faces    Points   Surface topology                  
    inlet               8991     9390     ok (non-closed singly connected)  
    outlet              9923     11912    ok (non-closed singly connected)  
    walls               927160   893087   multiply connected (shared edge)  
  <<Writing 41975 conflicting points to set nonManifoldPoints

Checking geometry...
    Overall domain bounding box (-0.0041 -0.0025 -5e-05) (0.01555 0.01395 0.0011)
    Mesh has 3 geometric (non-empty/wedge) directions (1 1 1)
    Mesh has 3 solution (non-empty) directions (1 1 1)
    Boundary openness (1.86932e-19 2.16764e-18 -2.07891e-16) OK.
    Max cell openness = 1.65436e-16 OK.
    Max aspect ratio = 1 OK.
    Minimum face area = 2.5e-09. Maximum face area = 2.5e-09.  Face area magnitudes OK.
    Min volume = 1.25e-13. Max volume = 1.25e-13.  Total volume = 2.56567e-07.  Cell volumes OK.
    Mesh non-orthogonality Max: 0 average: 0
    Non-orthogonality check OK.
    Face pyramids OK.
    Max skewness = 3.71396e-13 OK.
    Coupled point location match (average 0) OK.

Mesh OK.

End

simpleFoam log

[...]
Create time

Create mesh for time = 0


SIMPLE: convergence criteria
    field p	 tolerance 0.001
    field U	 tolerance 0.0001

Reading field p

Reading field U

Reading/calculating face flux field phi

Selecting incompressible transport model Newtonian
Selecting turbulence model type laminar
No MRF models present

No finite volume options present


Starting time loop

Time = 1

smoothSolver:  Solving for Ux, Initial residual = 1, Final residual = 0.0899429, No Iterations 1
smoothSolver:  Solving for Uy, Initial residual = 1, Final residual = 0.0466972, No Iterations 1
smoothSolver:  Solving for Uz, Initial residual = 1, Final residual = 0.054899, No Iterations 1
[5] #0  [0] #0  [1] #0  [2] #0  [3] #0  [4] #0  Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)Foam::error::printStack(Foam::Ostream&)--------------------------------------------------------------------------
A 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 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:          [[43444,1],0] (PID 29304)

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.
--------------------------------------------------------------------------
 at ??:?
 at ??:?
 at ??:?
[4] #1  Foam::sigFpe::sigHandler(int) at ??:?
[5] #1  Foam::sigFpe::sigHandler(int)[1] #1  Foam::sigFpe::sigHandler(int)[0] #1  Foam::sigFpe::sigHandler(int) at ??:?
 at ??:?
[3] #1  Foam::sigFpe::sigHandler(int)[2] #1  Foam::sigFpe::sigHandler(int) at ??:?
[0] #2  ? at ??:?
[5] #2  ? at ??:?
[4] #2  ? at ??:?
[1] #2  ? at ??:?
[2] #2  ? at ??:?
[3] #2  ? in "/usr/lib64/libc.so.6"
 in "/usr/lib64/libc.so.6"
[0] #3  Foam::DICPreconditioner::calcReciprocalD(Foam::Field<double>&, Foam::lduMatrix const&)[5] #3  Foam::DICPreconditioner::calcReciprocalD(Foam::Field<double>&, Foam::lduMatrix const&) in "/usr/lib64/libc.so.6"
 in "/usr/lib64/libc.so.6"
[...]

My thoughts
Summarized: Mesh is not fine (but: no complaints by Hypermesh while exporting, checkMesh okay), solver is exploding while calculating pressure. Second cluster gives same error msg:

Time = 1

smoothSolver:  Solving for Ux, Initial residual = 1, Final residual = 0.0208945, No Iterations 2
smoothSolver:  Solving for Uy, Initial residual = 1, Final residual = 0.0523874, No Iterations 1
smoothSolver:  Solving for Uz, Initial residual = 1, Final residual = 0.0648027, No Iterations 1
GAMG:  Solving for p, Initial residual = 1, Final residual = nan, No Iterations 1000
time step continuity errors : sum local = nan, global = -nan, cumulative = -nan
ExecutionTime = 54.97 s  ClockTime = 55 s

--------------------------------------------------------------------------
MPI_ABORT was invoked on rank 2 in communicator MPI_COMM_WORLD 
with errorcode 1.
[...]

But what is the problem here? Anything to complain about "non-manifold-points" or "regions not connected by any face"

I've tested many configurations. This case scenario works with a very simple (and therefore different) mesh (only cavity) on two independent clusters.

Would be that nice, if somebody could give support. Working on this case since 3 weeks, without helpful outcome.


Greetings,
Matthias