CFD Online Discussion Forums - k-omega SST blew up after first few iterations

I am trying to model the external flow over a bike, in order to obtain the CdA. I borrowed the case from motorBike tutorial. I slightly modified the initial conditions as follows:

flowVelocity (0 0 15);
pressure 0;
turbulentKE 0.00135;
turbulentOmega 900;

The initial values I used in k and omega were based on some researches, which used turbulence intensity level = 2% and eddy viscosity ratio = 0.1.

Here is what I got from the log.simpleFoam:

Code:

Create time



Create mesh for time = 0



[AdminPC:02105] 5 more processes have sent help message help-btl-vader.txt / cma-permission-denied

[AdminPC:02105] Set MCA parameter "orte_base_help_aggregate" to 0 to see all help / error messages



SIMPLE: Convergence criteria found

        U: tolerance 0.0001

        p: tolerance 0.0001

        "(k|omega)": tolerance 0.0001



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 kOmegaSST

Selecting patchDistMethod meshWave

RAS

{

    RASModel        kOmegaSST;

    turbulence      on;

    printCoeffs     on;

    alphaK1         0.85;

    alphaK2         1;

    alphaOmega1     0.5;

    alphaOmega2     0.856;

    gamma1          0.555556;

    gamma2          0.44;

    beta1           0.075;

    beta2           0.0828;

    betaStar        0.09;

    a1              0.31;

    b1              1;

    c1              10;

    F3              false;

}



No MRF models present



No finite volume options present



Starting time loop



streamLine streamLines:

    automatic track length specified through number of sub cycles : 5



Reading surface description:

    yNormal



forces forceCoeffs1:

    Not including porosity effects

forceCoeffs forceCoeffs1:

    Not including porosity effects

Time = 1



smoothSolver:  Solving for Ux, Initial residual = 0.176082, Final residual = 0.0175161, No Iterations 8

smoothSolver:  Solving for Uy, Initial residual = 0.0854752, Final residual = 0.0078422, No Iterations 6

smoothSolver:  Solving for Uz, Initial residual = 0.0535574, Final residual = 0.00446781, No Iterations 9

GAMG:  Solving for p, Initial residual = 1, Final residual = 0.00968802, No Iterations 15

time step continuity errors : sum local = 9.19838e-08, global = 1.35003e-09, cumulative = 1.35003e-09

smoothSolver:  Solving for omega, Initial residual = 0.999998, Final residual = 2.29698e-05, No Iterations 1

smoothSolver:  Solving for k, Initial residual = 1, Final residual = 6.96747e-05, No Iterations 1

ExecutionTime = 252.73 s  ClockTime = 563 s



forceCoeffs forceCoeffs1 write:

    Cm    = 0.404453

    Cd    = 0.754425

    Cl    = -0.0101646

    Cl(f) = 0.399371

    Cl(r) = -0.409535



Time = 2



smoothSolver:  Solving for Ux, Initial residual = 0.114146, Final residual = 0.00945059, No Iterations 8

smoothSolver:  Solving for Uy, Initial residual = 0.03572, Final residual = 0.0033767, No Iterations 7

smoothSolver:  Solving for Uz, Initial residual = 0.268761, Final residual = 0.023381, No Iterations 8

GAMG:  Solving for p, Initial residual = 0.00423399, Final residual = 3.88164e-05, No Iterations 14

time step continuity errors : sum local = 7.09901e-08, global = 1.05225e-09, cumulative = 2.40228e-09

smoothSolver:  Solving for omega, Initial residual = 0.786768, Final residual = 6.02541e-05, No Iterations 1

smoothSolver:  Solving for k, Initial residual = 0.347618, Final residual = 8.09935e-05, No Iterations 1

ExecutionTime = 358.52 s  ClockTime = 941 s



forceCoeffs forceCoeffs1 write:

    Cm    = 0.372383

    Cd    = 0.710432

    Cl    = -0.0032843

    Cl(f) = 0.370741

    Cl(r) = -0.374025



Time = 3



smoothSolver:  Solving for Ux, Initial residual = 0.134328, Final residual = 0.0118087, No Iterations 8

smoothSolver:  Solving for Uy, Initial residual = 0.116996, Final residual = 0.0105707, No Iterations 7

smoothSolver:  Solving for Uz, Initial residual = 0.0580452, Final residual = 0.00576293, No Iterations 7

GAMG:  Solving for p, Initial residual = 0.00317963, Final residual = 3.03476e-05, No Iterations 18

time step continuity errors : sum local = 7.20084e-08, global = 7.35963e-10, cumulative = 3.13824e-09

smoothSolver:  Solving for omega, Initial residual = 0.373588, Final residual = 9.57613e-05, No Iterations 1

smoothSolver:  Solving for k, Initial residual = 0.103448, Final residual = 8.1809e-05, No Iterations 1

ExecutionTime = 509.1 s  ClockTime = 1274 s



forceCoeffs forceCoeffs1 write:

    Cm    = 0.28686

    Cd    = 0.550375

    Cl    = 0.0178247

    Cl(f) = 0.295772

    Cl(r) = -0.277947



Time = 4



smoothSolver:  Solving for Ux, Initial residual = 0.581453, Final residual = 0.0506933, No Iterations 7

smoothSolver:  Solving for Uy, Initial residual = 0.438063, Final residual = 0.0375534, No Iterations 14

smoothSolver:  Solving for Uz, Initial residual = 0.28364, Final residual = 0.0228554, No Iterations 19

GAMG:  Solving for p, Initial residual = 0.100663, Final residual = 0.000964993, No Iterations 24

time step continuity errors : sum local = 2.71584e-06, global = -6.86095e-08, cumulative = -6.54713e-08

smoothSolver:  Solving for omega, Initial residual = 0.156237, Final residual = 0.000151387, No Iterations 1

smoothSolver:  Solving for k, Initial residual = 0.0248487, Final residual = 9.03384e-05, No Iterations 1

ExecutionTime = 625.86 s  ClockTime = 1558 s



forceCoeffs forceCoeffs1 write:

    Cm    = -2.36372

    Cd    = 5.23947

    Cl    = -45.4406

    Cl(f) = -25.084

    Cl(r) = -20.3566



Time = 5



smoothSolver:  Solving for Ux, Initial residual = 0.748694, Final residual = 0.0654467, No Iterations 6

smoothSolver:  Solving for Uy, Initial residual = 0.707975, Final residual = 0.0671149, No Iterations 10

smoothSolver:  Solving for Uz, Initial residual = 0.645301, Final residual = 0.0580618, No Iterations 11

GAMG:  Solving for p, Initial residual = 0.331992, Final residual = 0.00325251, No Iterations 29

time step continuity errors : sum local = 4.57856e-05, global = 1.35323e-06, cumulative = 1.28776e-06

smoothSolver:  Solving for omega, Initial residual = 0.0619606, Final residual = 0.000791318, No Iterations 1

smoothSolver:  Solving for k, Initial residual = 0.00576973, Final residual = 0.000313824, No Iterations 2

ExecutionTime = 753.75 s  ClockTime = 1825 s



forceCoeffs forceCoeffs1 write:

    Cm    = 48393.6

    Cd    = 355643

    Cl    = -193536

    Cl(f) = -48374.2

    Cl(r) = -145161



Time = 6



smoothSolver:  Solving for Ux, Initial residual = 0.77583, Final residual = 0.0469625, No Iterations 11

smoothSolver:  Solving for Uy, Initial residual = 0.647136, Final residual = 0.0587523, No Iterations 9

smoothSolver:  Solving for Uz, Initial residual = 0.801675, Final residual = 0.0450629, No Iterations 11

GAMG:  Solving for p, Initial residual = 2.42318e-05, Final residual = 2.34325e-07, No Iterations 43

time step continuity errors : sum local = 0.000116095, global = 5.64454e-06, cumulative = 6.9323e-06

smoothSolver:  Solving for omega, Initial residual = 0.0295412, Final residual = 0.00216916, No Iterations 2

smoothSolver:  Solving for k, Initial residual = 0.00243104, Final residual = 0.000230323, No Iterations 3

ExecutionTime = 908.36 s  ClockTime = 2133 s



forceCoeffs forceCoeffs1 write:

    Cm    = -735398

    Cd    = -1.66962e+06

    Cl    = -1.74826e+07

    Cl(f) = -9.47672e+06

    Cl(r) = -8.00593e+06



Time = 7



smoothSolver:  Solving for Ux, Initial residual = 0.577761, Final residual = 0.0517967, No Iterations 47

smoothSolver:  Solving for Uy, Initial residual = 0.570563, Final residual = 0.0531017, No Iterations 47

smoothSolver:  Solving for Uz, Initial residual = 0.546372, Final residual = 0.0538754, No Iterations 36

GAMG:  Solving for p, Initial residual = 0.0134, Final residual = 0.0431707, No Iterations 1000

time step continuity errors : sum local = 500.302, global = -256.052, cumulative = -256.052

smoothSolver:  Solving for omega, Initial residual = 0.726855, Final residual = 0.0688681, No Iterations 4

smoothSolver:  Solving for k, Initial residual = 0.053017, Final residual = 0.00485332, No Iterations 4

ExecutionTime = 2723 s  ClockTime = 4119 s



forceCoeffs forceCoeffs1 write:

    Cm    = 1.42517e+06

    Cd    = 7.85747e+06

    Cl    = -2.46218e+07

    Cl(f) = -1.08857e+07

    Cl(r) = -1.37361e+07



Time = 8



smoothSolver:  Solving for Ux, Initial residual = 0.612081, Final residual = 0.0499664, No Iterations 29

smoothSolver:  Solving for Uy, Initial residual = 0.562296, Final residual = 0.0483684, No Iterations 28

smoothSolver:  Solving for Uz, Initial residual = 0.628358, Final residual = 0.0614706, No Iterations 14

GAMG:  Solving for p, Initial residual = 0.999964, Final residual = 0.0500564, No Iterations 1000

time step continuity errors : sum local = 1.61271e+08, global = -40286.8, cumulative = -40542.9

smoothSolver:  Solving for omega, Initial residual = 0.00412419, Final residual = 0.000290188, No Iterations 4

smoothSolver:  Solving for k, Initial residual = 0.00274375, Final residual = 0.000233623, No Iterations 5

ExecutionTime = 4529.61 s  ClockTime = 6088 s



forceCoeffs forceCoeffs1 write:

    Cm    = -6.60893e+13

    Cd    = -5.13466e+14

    Cl    = 1.211e+14

    Cl(f) = -5.53934e+12

    Cl(r) = 1.26639e+14



Time = 9



smoothSolver:  Solving for Ux, Initial residual = 0.804576, Final residual = 13.5575, No Iterations 1000

smoothSolver:  Solving for Uy, Initial residual = 0.785135, Final residual = 82.7634, No Iterations 1000

smoothSolver:  Solving for Uz, Initial residual = 0.874744, Final residual = 9.53614, No Iterations 1000

-------------------------------------------------------

Primary job  terminated normally, but 1 process returned

a non-zero exit code.. Per user-direction, the job has been aborted.

-------------------------------------------------------

--------------------------------------------------------------------------

mpirun detected that one or more processes exited with non-zero status, thus causing

the job to be terminated. The first process to do so was:



  Process name: [[12118,1],0]

  Exit code:    145

--------------------------------------------------------------------------

The results blew up started from 4th iteration. Does anyone know how to fix it? Below I will put my snappyHexMeshDict, fvSchemes and fvSolution.

snappyHexMeshDict:

Code:

castellatedMesh true;

snap            true;

addLayers       true;



{

    figure

    {

        type triSurfaceMesh;

        file "figure.stl";

    }



    refinementBox

    {

        type searchableBox;

        min ( -750 0 -1000);

        max ( 1830 2685 2640);

    }

    

};



castellatedMeshControls

{

    maxLocalCells 1000000;

    maxGlobalCells 30000000;

    minRefinementCells 15;

    maxLoadUnbalance 0.15;

    nCellsBetweenLevels 3;

    features

    (

        {

            file "figure.eMesh";

            level 7;

        }

    );

    refinementSurfaces

    {

        figure

        {

            level (7 7);

            patchInfo

            {

                type wall;

                inGroups (figureGroup);

            }

        }

    }

    resolveFeatureAngle 20;

    refinementRegions

    {

        refinementBox

        {

            mode inside;

            levels ((1E15 4));

        }



        figure

        {

                mode distance;

                levels 

                (

                        (2 8)

                        (10 6)                                        

                );

        }

    }

    locationInMesh (402.1 1802 1002.7) ;

    allowFreeStandingZoneFaces true;

}



snapControls

{

    nSmoothPatch 5;

    tolerance 2.25;

    nSolveIter 30;

    nRelaxIter 5;

        nFeatureSnapIter 10;

        implicitFeatureSnap false;

        explicitFeatureSnap true;

        multiRegionFeatureSnap false;

}



addLayersControls

{

    relativeSizes true;

    layers

    {

        "(lowerWall|figure).*"

        {

            nSurfaceLayers 10;

        }

    }

    expansionRatio 1.2;

    thickness 0.8;

    minThickness 0.0001;

    nGrow 0;

    featureAngle 180;

    slipFeatureAngle 30;

    nRelaxIter 5;

    nSmoothSurfaceNormals 1;

    nSmoothNormals 3;

    nSmoothThickness 10;

    maxFaceThicknessRatio 0.6;

    maxThicknessToMedialRatio 0.3;

    minMedianAxisAngle 90;

    nBufferCellsNoExtrude 0;

    nLayerIter 15;

}



meshQualityControls

{

    #include "meshQualityDict"

}



writeFlags

(

    scalarLevels

    layerSets

    layerFields

);



mergeTolerance 1e-6;

fvSchemes:

Code:

ddtSchemes

{

    default         steadyState;

}



gradSchemes

{

    default         Gauss linear;

    grad(U)         cellLimited Gauss linear 1;

}



divSchemes

{

    default         none;

    div(phi,U)      bounded Gauss linearUpwindV grad(U);

    div(phi,k)      bounded Gauss upwind;

    div(phi,omega)  bounded Gauss upwind;

    div((nuEff*dev2(T(grad(U))))) Gauss linear;

}



laplacianSchemes

{

    default         Gauss linear corrected;

}



interpolationSchemes

{

    default         linear;

}



snGradSchemes

{

    default         corrected;

}



wallDist

{

    method meshWave;

}

fvSolution:

Code:

solvers

{

    p

    {

        solver          GAMG;

        smoother        GaussSeidel;

        tolerance       1e-7;

        relTol          0.01;

    }



    Phi

    {

        $p;

    }



    U

    {

        solver          smoothSolver;

        smoother        GaussSeidel;

        tolerance       1e-8;

        relTol          0.1;

        nSweeps         1;

    }



    k

    {

        solver          smoothSolver;

        smoother        GaussSeidel;

        tolerance       1e-8;

        relTol          0.1;

        nSweeps         1;

    }



    omega

    {

        solver          smoothSolver;

        smoother        GaussSeidel;

        tolerance       1e-8;

        relTol          0.1;

        nSweeps         1;

    }

}



SIMPLE

{

    nNonOrthogonalCorrectors 0;

    consistent yes;

    residualControl

    {

        U                1e-4;

        p                1e-4;

        "(k|omega)"        1e-4;

    }

}



potentialFlow

{

    nNonOrthogonalCorrectors 10;

}



relaxationFactors

{

    equations

    {

        U               0.9;

        k               0.7;

        omega           0.7;

    }

}



cache

{

    grad(U);

}

Please see if any other information is required. Thanks a lot.

Quote:

Originally Posted by hxaxtma (Post 733349)

I guess this is a highly non Orthogonal mesh - can be found in checkMesh log File

I recommend following settings:

nNonOrthogonalCorrectors 3;

Pressure equation is diverging, therefore set:

relaxationFactors of pressure p 0.3,
U 0.7 and turbulence variables 0.3

Set consistent to no in the Simple Dict

If this is not running and your mesh is OK something is wrong with your BCs

Thanks for your suggestions. I followed your guide and ran again, but the results were still diverging. Below is the log.simpleFoam(I cut it at iteration 9 because I know it wont do good):

Code:

Create mesh for time = 0



[AdminPC:07679] 5 more processes have sent help message help-btl-vader.txt / cma-permission-denied

[AdminPC:07679] Set MCA parameter "orte_base_help_aggregate" to 0 to see all help / error messages



SIMPLE: Convergence criteria found

        U: tolerance 0.0001

        p: tolerance 0.0001

        "(k|omega)": tolerance 0.0001



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 kOmegaSST

Selecting patchDistMethod meshWave

RAS

{

    RASModel        kOmegaSST;

    turbulence      on;

    printCoeffs     on;

    alphaK1         0.85;

    alphaK2         1;

    alphaOmega1     0.5;

    alphaOmega2     0.856;

    gamma1          0.555556;

    gamma2          0.44;

    beta1           0.075;

    beta2           0.0828;

    betaStar        0.09;

    a1              0.31;

    b1              1;

    c1              10;

    F3              false;

}



No MRF models present



No finite volume options present



Starting time loop



streamLine streamLines:

    automatic track length specified through number of sub cycles : 5



Reading surface description:

    yNormal



forces forceCoeffs1:

    Not including porosity effects

forceCoeffs forceCoeffs1:

    Not including porosity effects

Time = 1



smoothSolver:  Solving for Ux, Initial residual = 0.0456653, Final residual = 0.00423798, No Iterations 3

smoothSolver:  Solving for Uy, Initial residual = 0.0288288, Final residual = 0.00174395, No Iterations 3

smoothSolver:  Solving for Uz, Initial residual = 0.015543, Final residual = 0.000777086, No Iterations 4

GAMG:  Solving for p, Initial residual = 1, Final residual = 0.00897626, No Iterations 12

GAMG:  Solving for p, Initial residual = 0.00258742, Final residual = 2.44815e-05, No Iterations 9

GAMG:  Solving for p, Initial residual = 0.000234184, Final residual = 2.20371e-06, No Iterations 28

GAMG:  Solving for p, Initial residual = 3.7742e-05, Final residual = 3.56882e-07, No Iterations 28

time step continuity errors : sum local = 2.33207e-10, global = 1.31804e-11, cumulative = 1.31804e-11

smoothSolver:  Solving for omega, Initial residual = 0.0432445, Final residual = 6.84685e-05, No Iterations 1

smoothSolver:  Solving for k, Initial residual = 1, Final residual = 0.00190103, No Iterations 1

ExecutionTime = 303.55 s  ClockTime = 544 s



forceCoeffs forceCoeffs1 write:

    Cm    = 0.795466

    Cd    = 1.52038

    Cl    = -0.00376598

    Cl(f) = 0.793583

    Cl(r) = -0.797349



Time = 2



smoothSolver:  Solving for Ux, Initial residual = 0.0616887, Final residual = 0.00374667, No Iterations 4

smoothSolver:  Solving for Uy, Initial residual = 0.0243984, Final residual = 0.00133365, No Iterations 4

smoothSolver:  Solving for Uz, Initial residual = 0.028181, Final residual = 0.00171954, No Iterations 4

GAMG:  Solving for p, Initial residual = 0.0119031, Final residual = 0.000116838, No Iterations 12

GAMG:  Solving for p, Initial residual = 0.00487985, Final residual = 4.76482e-05, No Iterations 9

GAMG:  Solving for p, Initial residual = 0.000448644, Final residual = 4.26444e-06, No Iterations 26

GAMG:  Solving for p, Initial residual = 7.1785e-05, Final residual = 6.86387e-07, No Iterations 27

time step continuity errors : sum local = 4.649e-10, global = -3.29865e-11, cumulative = -1.98061e-11

smoothSolver:  Solving for omega, Initial residual = 0.0232035, Final residual = 5.38076e-05, No Iterations 1

smoothSolver:  Solving for k, Initial residual = 0.24792, Final residual = 0.000678387, No Iterations 1

ExecutionTime = 505.78 s  ClockTime = 863 s



forceCoeffs forceCoeffs1 write:

    Cm    = -2.58056

    Cd    = -4.90158

    Cl    = 0.0861271

    Cl(f) = -2.5375

    Cl(r) = 2.62362



Time = 3



smoothSolver:  Solving for Ux, Initial residual = 0.125752, Final residual = 0.00786615, No Iterations 4

smoothSolver:  Solving for Uy, Initial residual = 0.040605, Final residual = 0.00248977, No Iterations 4

smoothSolver:  Solving for Uz, Initial residual = 0.0650774, Final residual = 0.00419616, No Iterations 4

GAMG:  Solving for p, Initial residual = 0.0235075, Final residual = 0.000216227, No Iterations 12

GAMG:  Solving for p, Initial residual = 0.00310908, Final residual = 2.99842e-05, No Iterations 9

GAMG:  Solving for p, Initial residual = 0.000296906, Final residual = 2.87985e-06, No Iterations 24

GAMG:  Solving for p, Initial residual = 4.76489e-05, Final residual = 4.60334e-07, No Iterations 26

time step continuity errors : sum local = 9.14815e-10, global = 7.63309e-11, cumulative = 5.65248e-11

smoothSolver:  Solving for omega, Initial residual = 0.0130879, Final residual = 4.40088e-05, No Iterations 1

smoothSolver:  Solving for k, Initial residual = 0.115244, Final residual = 0.000442352, No Iterations 1

ExecutionTime = 711.59 s  ClockTime = 1235 s



forceCoeffs forceCoeffs1 write:

    Cm    = 7.08031

    Cd    = 13.1402

    Cl    = -0.259661

    Cl(f) = 6.95048

    Cl(r) = -7.21014



Time = 4



smoothSolver:  Solving for Ux, Initial residual = 0.214588, Final residual = 0.0133585, No Iterations 4

smoothSolver:  Solving for Uy, Initial residual = 0.0770733, Final residual = 0.00473664, No Iterations 4

smoothSolver:  Solving for Uz, Initial residual = 0.195012, Final residual = 0.0124302, No Iterations 4

GAMG:  Solving for p, Initial residual = 0.0177483, Final residual = 0.000176726, No Iterations 11

GAMG:  Solving for p, Initial residual = 0.00386416, Final residual = 3.5565e-05, No Iterations 10

GAMG:  Solving for p, Initial residual = 0.000371768, Final residual = 3.54374e-06, No Iterations 23

GAMG:  Solving for p, Initial residual = 5.95072e-05, Final residual = 5.70419e-07, No Iterations 25

time step continuity errors : sum local = 1.84151e-09, global = -1.82247e-10, cumulative = -1.25722e-10

smoothSolver:  Solving for omega, Initial residual = 0.00788961, Final residual = 3.74303e-05, No Iterations 1

smoothSolver:  Solving for k, Initial residual = 0.0656286, Final residual = 0.000343864, No Iterations 1

ExecutionTime = 914.35 s  ClockTime = 1576 s



forceCoeffs forceCoeffs1 write:

    Cm    = -16.2509

    Cd    = -29.4589

    Cl    = 0.694666

    Cl(f) = -15.9036

    Cl(r) = 16.5982



Time = 5



smoothSolver:  Solving for Ux, Initial residual = 0.420152, Final residual = 0.025847, No Iterations 4

smoothSolver:  Solving for Uy, Initial residual = 0.151328, Final residual = 0.00917183, No Iterations 4

smoothSolver:  Solving for Uz, Initial residual = 0.724336, Final residual = 0.0454167, No Iterations 4

GAMG:  Solving for p, Initial residual = 0.0234195, Final residual = 0.000228815, No Iterations 11

GAMG:  Solving for p, Initial residual = 0.00359141, Final residual = 3.28205e-05, No Iterations 10

GAMG:  Solving for p, Initial residual = 0.000347374, Final residual = 3.42699e-06, No Iterations 22

GAMG:  Solving for p, Initial residual = 5.55193e-05, Final residual = 5.18951e-07, No Iterations 25

time step continuity errors : sum local = 3.52172e-09, global = 2.49334e-10, cumulative = 1.23612e-10

smoothSolver:  Solving for omega, Initial residual = 0.00504652, Final residual = 3.29567e-05, No Iterations 1

smoothSolver:  Solving for k, Initial residual = 0.0413384, Final residual = 0.000287633, No Iterations 1

ExecutionTime = 1117.53 s  ClockTime = 1934 s



forceCoeffs forceCoeffs1 write:

    Cm    = 35.4112

    Cd    = 62.5706

    Cl    = -1.46642

    Cl(f) = 34.678

    Cl(r) = -36.1444



Time = 6



smoothSolver:  Solving for Ux, Initial residual = 0.540335, Final residual = 0.0328771, No Iterations 4

smoothSolver:  Solving for Uy, Initial residual = 0.256176, Final residual = 0.0151566, No Iterations 4

smoothSolver:  Solving for Uz, Initial residual = 0.749173, Final residual = 0.0459364, No Iterations 4

GAMG:  Solving for p, Initial residual = 0.0232613, Final residual = 0.000211777, No Iterations 11

GAMG:  Solving for p, Initial residual = 0.00378945, Final residual = 3.54794e-05, No Iterations 10

GAMG:  Solving for p, Initial residual = 0.00036875, Final residual = 3.59724e-06, No Iterations 22

GAMG:  Solving for p, Initial residual = 5.9962e-05, Final residual = 5.69627e-07, No Iterations 24

time step continuity errors : sum local = 6.98985e-09, global = -4.32232e-10, cumulative = -3.08621e-10

smoothSolver:  Solving for omega, Initial residual = 0.00338321, Final residual = 3.0473e-05, No Iterations 1

smoothSolver:  Solving for k, Initial residual = 0.0277725, Final residual = 0.000250897, No Iterations 1

ExecutionTime = 1308.15 s  ClockTime = 2280 s



forceCoeffs forceCoeffs1 write:

    Cm    = -73.1295

    Cd    = -126.245

    Cl    = 2.56818

    Cl(f) = -71.8454

    Cl(r) = 74.4136



Time = 7



smoothSolver:  Solving for Ux, Initial residual = 0.752046, Final residual = 0.0448627, No Iterations 4

smoothSolver:  Solving for Uy, Initial residual = 0.430047, Final residual = 0.0249392, No Iterations 4

smoothSolver:  Solving for Uz, Initial residual = 0.551617, Final residual = 0.0336876, No Iterations 4

GAMG:  Solving for p, Initial residual = 0.0269677, Final residual = 0.000232386, No Iterations 11

GAMG:  Solving for p, Initial residual = 0.00380056, Final residual = 3.53977e-05, No Iterations 10

GAMG:  Solving for p, Initial residual = 0.00037507, Final residual = 3.55969e-06, No Iterations 22

GAMG:  Solving for p, Initial residual = 6.14032e-05, Final residual = 5.99133e-07, No Iterations 23

time step continuity errors : sum local = 1.41695e-08, global = 6.52369e-10, cumulative = 3.43748e-10

smoothSolver:  Solving for omega, Initial residual = 0.00234028, Final residual = 3.02726e-05, No Iterations 1

smoothSolver:  Solving for k, Initial residual = 0.0194432, Final residual = 0.000227259, No Iterations 1

ExecutionTime = 1491.96 s  ClockTime = 2579 s



forceCoeffs forceCoeffs1 write:

    Cm    = 146.466

    Cd    = 247.633

    Cl    = -3.05498

    Cl(f) = 144.938

    Cl(r) = -147.993



Time = 8



smoothSolver:  Solving for Ux, Initial residual = 0.776731, Final residual = 0.0455646, No Iterations 4

smoothSolver:  Solving for Uy, Initial residual = 0.558656, Final residual = 0.031481, No Iterations 4

smoothSolver:  Solving for Uz, Initial residual = 0.653407, Final residual = 0.0383689, No Iterations 4

GAMG:  Solving for p, Initial residual = 0.0259683, Final residual = 0.000237545, No Iterations 11

GAMG:  Solving for p, Initial residual = 0.00340573, Final residual = 3.29827e-05, No Iterations 11

GAMG:  Solving for p, Initial residual = 0.000344274, Final residual = 3.43903e-06, No Iterations 22

GAMG:  Solving for p, Initial residual = 5.87626e-05, Final residual = 5.69208e-07, No Iterations 23

time step continuity errors : sum local = 2.49218e-08, global = 6.18566e-10, cumulative = 9.62314e-10

smoothSolver:  Solving for omega, Initial residual = 0.00167082, Final residual = 3.52362e-05, No Iterations 1

smoothSolver:  Solving for k, Initial residual = 0.0139952, Final residual = 0.00021044, No Iterations 1

ExecutionTime = 1673.7 s  ClockTime = 2865 s



forceCoeffs forceCoeffs1 write:

    Cm    = -287.239

    Cd    = -477.46

    Cl    = 2.13309

    Cl(f) = -286.173

    Cl(r) = 288.306



Time = 9



smoothSolver:  Solving for Ux, Initial residual = 0.846681, Final residual = 0.0493988, No Iterations 4

smoothSolver:  Solving for Uy, Initial residual = 0.717908, Final residual = 0.0404963, No Iterations 4

smoothSolver:  Solving for Uz, Initial residual = 0.793609, Final residual = 0.0459932, No Iterations 4

GAMG:  Solving for p, Initial residual = 0.0262227, Final residual = 0.000249765, No Iterations 11

GAMG:  Solving for p, Initial residual = 0.00303599, Final residual = 3.00778e-05, No Iterations 12

GAMG:  Solving for p, Initial residual = 0.000305505, Final residual = 2.83807e-06, No Iterations 25

GAMG:  Solving for p, Initial residual = 5.17231e-05, Final residual = 5.14271e-07, No Iterations 24

time step continuity errors : sum local = 4.23329e-08, global = -4.095e-09, cumulative = -3.13269e-09

smoothSolver:  Solving for omega, Initial residual = 0.00125448, Final residual = 4.59583e-05, No Iterations 1

smoothSolver:  Solving for k, Initial residual = 0.0103348, Final residual = 0.000213194, No Iterations 1

ExecutionTime = 1859.81 s  ClockTime = 3174 s



regIOobject::readIfModified() : 

    Re-reading object controlDict from file "/home/taeioum/OpenFOAM/taeioum-dev/run/pos/pos11/system/controlDict"

forceCoeffs forceCoeffs1 write:

    Cm    = 547.583

    Cd    = 900.165

    Cl    = 2.90921

    Cl(f) = 549.038

    Cl(r) = -546.129



End



Finalising parallel run

I also did the checkMesh utility and it gave:

Code:

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

    frontAndBack        4300     4524     ok (non-closed singly connected)

    inlet               750      806      ok (non-closed singly connected)

    outlet              750      806      ok (non-closed singly connected)

    lowerWall           2580     2697     ok (non-closed singly connected)

    upperWall           2580     2697     ok (non-closed singly connected)



Checking geometry...

    Overall domain bounding box (-5535 -7.4607e-14 -8190) (6615 10100 26216)

    Mesh has 3 geometric (non-empty/wedge) directions (1 1 1)

    Mesh has 3 solution (non-empty) directions (1 1 1)

    Boundary openness (1.50014e-15 1.26354e-14 -9.2466e-17) OK.

    Max cell openness = 2.17924e-15 OK.

    Max aspect ratio = 108.81 OK.

    Minimum face area = 0.00157481. Maximum face area = 173726.  Face area magnitudes OK.

    Min volume = 0.0160548. Max volume = 6.74569e+07.  Total volume = 4.22204e+12.  Cell volumes OK.

    Mesh non-orthogonality Max: 64.9971 average: 8.1902

    Non-orthogonality check OK.

    Face pyramids OK.

 ***Max skewness = 5.20766, 1 highly skew faces detected which may impair the quality of the results

  <<Writing 1 skew faces to set skewFaces

    Coupled point location match (average 0) OK.



Failed 1 mesh checks.

So is the problem relevant to the BC? Thanks a lot.