[giorgianig]

I am performing a pisoFoam simulation using the kOmega turbulence model. The simulation stops after the very first iteration without any error message, with very small residuals.

Here is the output:

/*---------------------------------------------------------------------------*\      
| =========                 |                                                 |                                                                                                                     | \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |                                                                                                                     |  \\    /   O peration     | Version:  2212                                  |                                                                                                                     |   \\  /    A nd           | Website:  www.openfoam.com                      |                                                                                                                                                              |    \\/     M anipulation  |        |                                                                           \*---------------------------------------------------------------------------*/                                                                                                                     Build  : _fd8c5e00-20221221 OPENFOAM=2212 version=2212                                                                                                                                              Arch   : "LSB;label=32;scalar=64"                                                                                                                                                                   Exec   : pisoFoam                                                                                                                                                                                   Date   : Mar 31 2023                                                                                                                                                                                Time   : 14:24:22                                                                                                                                                                                   Host   : L91031534                                                                                                                                                                                  PID    : 28339                                                                                                                                                                                      I/O    : uncollated                                                                                                                                                                                 Case   : /home/giorgio/OpenFOAM/2212/cfd/GrigliaPiramidi                                                                                                                                            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 

Create mesh for time = 0 

PISO: Operating solver in PISO mode   
Reading field p 
Reading field U     
Reading/calculating face flux field phi
Selecting incompressible transport model Newtonian
Selecting turbulence model type RAS
Selecting RAS turbulence model kOmega
RAS
{
     RASModel        kOmega; 
      turbulence      on;
      printCoeffs     on;
      betaStar        0.09;
      beta            0.072;
      gamma           0.52;
      alphaK          0.5;
      alphaOmega      0.5;
}
No MRF models present
No finite volume options present
Starting time loop
Time = 1e-05
Courant Number mean: 1.29184e-07 max: 9.69034e-06
smoothSolver:  Solving for Ux, Initial residual = 1, Final residual = 2.88595e-07, No Iterations 1
smoothSolver:  Solving for Uy, Initial residual = 1, Final residual = 4.20929e-07, No Iterations 1
smoothSolver:  Solving for Uz, Initial residual = 1, Final residual = 3.71605e-07, No Iterations 1
GAMG:  Solving for p, Initial residual = 1, Final residual = 0.0869702, No Iterations 14
GAMG:  Solving for p, Initial residual = 0.243386, Final residual = 0.0113372, No Iterations 1
time step continuity errors : sum local = 8.55951e-07, global = 1.08964e-09, cumulative = 1.08964e-09
GAMG:  Solving for p, Initial residual = 0.0356773, Final residual = 0.00255993, No Iterations 1 
GAMG:  Solving for p, Initial residual = 0.00842964, Final residual = 0.000497795, No Iterations 2 
time step continuity errors : sum local = 4.70351e-08, global = 1.57383e-09, cumulative = 2.66347e-09                                                                                               GAMG:  Solving for p, Initial residual = 0.00520673, Final residual = 0.000451653, No Iterations 1
GAMG:  Solving for p, Initial residual = 0.00504492, Final residual = 8.85867e-07, No Iterations 23 
time step continuity errors : sum local = 8.45234e-11, global = -2.13953e-12, cumulative = 2.66133e-09

The quality of the mesh is quite bad though. I am not sure the problem is that, in any case, the fact that stops without warnings and with small residuals is suspect.

Here is the output of checkMesh:

Mesh stats  
points:           4167670
faces:            36483185
internal faces:   35297638
cells:            17092207
faces per cell:   4.19962
boundary patches: 4
point zones:      0
face zones:       0
cell zones:       0

Overall number of cells of each type:
hexahedra:     0
prisms:        3392213 
wedges:        0
pyramids:      19782
tet wedges:    0
tetrahedra:    13680212
polyhedra:     0

Checking topology...
Boundary definition OK.
Cell to face addressing OK.
Point usage OK.
Upper triangular ordering OK.
Face vertices OK.
Number of regions: 1 (OK).

Checking patch topology for multiply connected surfaces...
Patch               Faces    Points   Surface topology
Inlet               954      526      ok (non-closed singly connected)
Outlet              910      504      ok (non-closed singly connected)
Lateral             66288    43790    ok (non-closed singly connected)
Wall                1117395  560117   ok (non-closed singly connected)

Checking faceZone topology for multiply connected surfaces...
No faceZones found.

Checking basic cellZone addressing...
No cellZones found.

Checking basic pointZone addressing...
No pointZones found.

Checking geometry...
Overall domain bounding box (0 -11 0) (2.117 4 7.23)
Mesh has 3 geometric (non-empty/wedge) directions (1 1 1)
Mesh has 3 solution (non-empty) directions (1 1 1)
Boundary openness (3.64032e-15 -1.89218e-16 2.24217e-16) OK.
***High aspect ratio cells found, Max aspect ratio: 1137.72, number of cells 1
<<Writing 1 cells with high aspect ratio to set highAspectRatioCells
Minimum face area = 1.9128e-08. Maximum face area = 0.054844.  Face area magnitudes OK.
Min volume = 1.11514e-12. Max volume = 0.0047743.  Total volume = 229.262.  Cell volumes OK.
Mesh non-orthogonality Max: 89.8501 average: 21.8076
*Number of severely non-orthogonal (> 70 degrees) faces: 28426.
Non-orthogonality check OK.
<<Writing 28426 non-orthogonal faces to set nonOrthoFaces
Face pyramids OK.
Max skewness = 3.78682 OK.
Coupled point location match (average 0) OK.
Failed 1 mesh checks.
End

Does anybody know what's going on?