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-   -   k-omega SST blew up after first few iterations (https://www.cfd-online.com/Forums/openfoam/217409-k-omega-sst-blew-up-after-first-few-iterations.html)

Jinjolee May 11, 2019 07:36

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.

hxaxtma May 11, 2019 16:23

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

Jinjolee May 12, 2019 03:40

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.

hxaxtma May 12, 2019 10:38

Can you somewhere upload your case...I could have a quick look

Jinjolee May 12, 2019 12:51

Quote:

Originally Posted by hxaxtma (Post 733383)
Can you somewhere upload your case...I could have a quick look

Sure. I will put it in google drive:
https://drive.google.com/file/d/1m-V...ew?usp=sharing

Thank you very much.


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