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Using rhoSimpleFoam for simulating steady state flow in a CD nozzle

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Old   January 14, 2020, 08:14
Default Using rhoSimpleFoam for simulating steady state flow in a CD nozzle
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Vignesh
Join Date: Nov 2019
Location: Dresden, Germany
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Hello everyone,


I'm trying to simulate a steady state CFD simulation in a CD nozzle using the solver rhoSimpleFoam. I'm facing some issues and I'm not able to validate my results.

I have attached all my files below.


I've created a very simple mesh in blockMesh, and have introduced mesh grading to refine the areas near the boundary. I attach my checkMesh results below

Code:

Build  : v1906 OPENFOAM=1906
Arch   : "LSB;label=32;scalar=64"
Exec   : checkMesh

Create time

Create mesh for time = 0

Time = 0

Mesh stats
    points:           121402
    internal points:  0
    faces:            240700
    internal faces:   119300
    cells:            60000
    faces per cell:   6
    boundary patches: 5
    point zones:      0
    face zones:       0
    cell zones:       0

Overall number of cells of each type:
    hexahedra:     60000
    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.
    Number of regions: 1 (OK).

Checking patch topology for multiply connected surfaces...
    Patch               Faces    Points   Surface topology                  
    inlet               100      202      ok (non-closed singly connected)  
    outlet              100      202      ok (non-closed singly connected)  
    upperWall           600      1202     ok (non-closed singly connected)  
    lowerWall           600      1202     ok (non-closed singly connected)  
    frontAndBack        120000   121402   ok (non-closed singly connected)  

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

Checking basic cellZone addressing...
    No cellZones found.

Checking geometry...
    Overall domain bounding box (0 0 -0.0005) (0.007 0.00065 0.0005)
    Mesh has 2 geometric (non-empty/wedge) directions (1 1 0)
    Mesh has 2 solution (non-empty) directions (1 1 0)
    All edges aligned with or perpendicular to non-empty directions.
    Boundary openness (-9.4603783e-18 -2.5693272e-15 -9.6253206e-16) OK.
    Max cell openness = 3.1682644e-16 OK.
    Max aspect ratio = 4.1564656 OK.
    Minimum face area = 2.6926964e-11. Maximum face area = 1.1995734e-08.  Face area magnitudes OK.
    Min volume = 2.6926964e-14. Max volume = 1.3989641e-13.  Total volume = 4.025e-09.  Cell volumes OK.
    Mesh non-orthogonality Max: 2.4483775 average: 1.6573628
    Non-orthogonality check OK.
    Face pyramids OK.
    Max skewness = 0.1068957 OK.
    Coupled point location match (average 0) OK.

Mesh OK.

End

For my boundary conditions, I specify that it is a pressure driven flow, with totalPressure BC at the inlet and fixedValue at the outlet.
For velocity, I specify zeroGradient at both inlet and outlet, with noSlip at the top wall
For temperature, I specify fixedValue at the inlet and zeroGradient at the outlet.
I also use symmetryPlane BC for the lower wall.


I have attached my boundary conditions below.


Code:
/*--------------------------------*- C++ -*----------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  v1906                                 |
|   \\  /    A nd           | Web:      www.OpenFOAM.com                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       volScalarField;
    location    "0";
    object      p;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions      [1 -1 -2 0 0 0 0];


internalField   uniform 101325;

boundaryField
{
    inlet
    {
        type            totalPressure;
        p0              uniform 200000;
        U               U;
        phi             phi;
        rho             rho;
        psi             none;
        gamma           1.4;   
    }
    outlet
    {
        type            fixedValue;
        value           uniform 101325;
        U               U;
        phi             phi;
        rho             rho;
        psi             none;
        gamma           1.4;
    }
    upperWall
    {
        type            zeroGradient;
    }
    lowerWall
    {
        type            symmetryPlane;
    }
    frontAndBack
    {
        type            empty;
    }
    defaultFaces
    {
    type         empty;
    }
}

Code:
/*--------------------------------*- C++ -*----------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  v1906                                 |
|   \\  /    A nd           | Web:      www.OpenFOAM.com                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       volVectorField;
    location    "0";
    object      U;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions      [0 1 -1 0 0 0 0];

internalField   uniform (0 0 0);

boundaryField
{
    inlet
    {
        type            zeroGradient;
    }
    outlet
    {
        type            zeroGradient;
    }
    upperWall
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    lowerWall
    {
        type            symmetryPlane;
    }
    frontAndBack
    {
        type            empty;
    }
}

Code:

/*--------------------------------*- C++ -*----------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  v1906                                 |
|   \\  /    A nd           | Web:      www.OpenFOAM.com                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       volScalarField;
    location    "0";
    object      T;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions      [0 0 0 1 0 0 0];


internalField   uniform 298;

boundaryField
{
    inlet
    {
        type            totalTemperature;
        T0              uniform 298;
        gamma           1.4;
    }
    outlet
    {
        type            zeroGradient;
    }
    upperWall
    {
        type            zeroGradient;
    }
    lowerWall
    {
        type            symmetryPlane;
    }
    frontAndBack
    {
        type            empty;
    }
}

I have read many posts in this forum, and people have recommended using the above boundary conditions for this case, so I'm not sure if there is a problem with this.


I'm attaching my fvSchemes, fvOptions and fvSolution files below. I'm not particularly sure as to which solver to use for this case, so I've just gone with the ones used in the tutorials.


Code:

/*--------------------------------*- C++ -*----------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  v1906                                 |
|   \\  /    A nd           | Web:      www.OpenFOAM.com                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       dictionary;
    object      fvSchemes;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

ddtSchemes
{
    default         steadyState;
}

gradSchemes
{
    default         Gauss linear;
}

divSchemes
{
    default             none;

    div(phi,U)          bounded Gauss upwind;
    div(((rho*nuEff)*dev2(T(grad(U)))))      Gauss linear;
    div(phi,e)          bounded Gauss upwind;
    div(phi,epsilon)    bounded Gauss upwind;
    div(phi,k)          bounded Gauss upwind;

    div(phid,p)         Gauss upwind;
    div(phi,Ekp)        bounded Gauss upwind;
    div((phi|interpolate(rho)),p)  Gauss upwind;
}

laplacianSchemes
{
    default         Gauss linear corrected;
}

interpolationSchemes
{
    default         linear;
}

gradSchemes
{
    default         faceMDLimited Gauss linear 0.5;
}

Code:

/*--------------------------------*- C++ -*----------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  v1906                                 |
|   \\  /    A nd           | Web:      www.OpenFOAM.com                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       dictionary;
    object      fvSolution;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

solvers
{
    p
    {
        solver          GAMG;
        smoother        GaussSeidel;
        tolerance       1e-6;
        relTol          0.01;
    }

    "(U|k|omega|e)"
    {
        solver          PBiCGStab;
        preconditioner  DILU;
        tolerance       1e-6;
        relTol          0.01;
    }
}

SIMPLE
{
    residualControl
    {
        p               1e-4;
        U               1e-4;
        "(k|omega|e)"   1e-4;
    }

    nNonOrthogonalCorrectors 0;
    pMinFactor      0.1;
    pMaxFactor      2;
}

relaxationFactors
{
    fields
    {
        p               0.7;
        rho             0.01;
    }
    equations
    {
        U               0.3;
        e               0.7;
        "(k|omega)"     0.7;
    }
}

Code:

/*--------------------------------*- C++ -*----------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  v1906                                 |
|   \\  /    A nd           | Web:      www.OpenFOAM.com                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       dictionary;
    object      fvOptions;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

limitT
{
    type       limitTemperature;
    min        101;
    max        1000;
    selectionMode all;
}

I'm getting some pretty weird results, and I'm not able to validate my pressure and velocity plots with the literature.

Code:

# Solver information
# Time              U_solver            Ux_initial          Ux_final            Ux_iters            Uy_initial          Uy_final            Uy_iters            U_converged         p_solver            p_initial           p_final             p_iters             p_converged     
1                   DILUPBiCGStab    1.00000000e+00    5.63145200e-03    1    1.00000000e+00    1.18017460e-03    1    false    GAMG    1.00000000e+00    3.08416040e-03    1    true
2                   DILUPBiCGStab    5.45963700e-01    1.69905430e-03    1    3.80739180e-01    1.41675240e-03    1    false    GAMG    2.26367420e-01    1.35376850e-03    3    true
3                   DILUPBiCGStab    4.30959060e-01    1.18852260e-03    1    2.92858160e-01    9.58617740e-04    1    false    GAMG    5.43492460e-02    3.31423630e-04    5    true
4                   DILUPBiCGStab    3.20779760e-01    8.65311860e-04    1    3.13826670e-01    9.23813840e-04    1    false    GAMG    1.69414160e-02    1.34136910e-04    5    true
5                   DILUPBiCGStab    2.56209780e-01    6.71257920e-04    1    1.71144620e-01    1.22977570e-03    1    false    GAMG    1.21129840e-02    1.03227820e-04    7    true
6                   DILUPBiCGStab    2.17978780e-01    6.08204110e-04    1    9.04764450e-02    7.59603610e-04    1    false    GAMG    6.80493660e-03    3.89629250e-05    9    true
7                   DILUPBiCGStab    1.88510680e-01    5.48296570e-04    1    5.44852170e-02    5.07802030e-04    1    false    GAMG    3.11672060e-03    1.45205410e-05    8    true
8                   DILUPBiCGStab    1.65910160e-01    5.03121960e-04    1    5.41494690e-02    2.58120990e-04    1    false    GAMG    1.78527080e-03    1.27787290e-05    10    true
9                   DILUPBiCGStab    1.48527580e-01    4.63248670e-04    1    5.09946720e-02    1.67642980e-04    1    false    GAMG    1.64403040e-03    1.33992420e-05    7    true
10                  DILUPBiCGStab    1.35567040e-01    4.37185820e-04    1    4.29566890e-02    1.33335920e-04    1    false    GAMG    1.14007820e-03    5.09410220e-06    9    true
11                  DILUPBiCGStab    1.25101200e-01    4.15358040e-04    1    3.67467390e-02    1.16270810e-04    1    false    GAMG    6.55856160e-04    5.55730280e-06    10    true
12                  DILUPBiCGStab    1.16331370e-01    3.94785310e-04    1    3.33904360e-02    1.14179040e-04    1    false    GAMG    4.08227720e-04    2.61137050e-06    10    true
13                  DILUPBiCGStab    1.08920730e-01    3.77537340e-04    1    3.04151770e-02    1.00107160e-04    1    false    GAMG    3.19891450e-04    1.40731650e-06    10    true
14                  DILUPBiCGStab    1.02434070e-01    3.60374460e-04    1    2.76140780e-02    8.70842780e-05    1    false    GAMG    3.38320430e-04    2.80018250e-06    8    true
15                  DILUPBiCGStab    9.68027690e-02    3.45042220e-04    1    2.51560640e-02    7.97026030e-05    1    false    GAMG    2.95921630e-04    2.04757530e-06    10    true
16                  DILUPBiCGStab    9.18175200e-02    3.30619640e-04    1    2.31945540e-02    7.53207720e-05    1    false    GAMG    2.78887010e-04    2.13555550e-06    10    true
17                  DILUPBiCGStab    8.73560160e-02    3.17040200e-04    1    2.14896960e-02    7.10223110e-05    1    false    GAMG    2.61539370e-04    1.78062630e-06    10    true
18                  DILUPBiCGStab    8.33385690e-02    3.04377940e-04    1    2.00176410e-02    6.69856460e-05    1    false    GAMG    2.39387170e-04    1.52502490e-06    10    true
19                  DILUPBiCGStab    7.96829250e-02    2.92397810e-04    1    1.87329790e-02    6.35358290e-05    1    false    GAMG    2.24885040e-04    1.49790800e-06    10    true
20                  DILUPBiCGStab    7.63413040e-02    2.81126890e-04    1    1.75887980e-02    6.02910410e-05    1    false    GAMG    2.10218520e-04    1.53493880e-06    10    true
21                  DILUPBiCGStab    7.32650410e-02    2.70438530e-04    1    1.65726370e-02    5.73083060e-05    1    false    GAMG    1.91872990e-04    1.52267420e-06    10    true
22                  DILUPBiCGStab    7.04232370e-02    2.60365690e-04    1    1.56758180e-02    5.46103790e-05    1    false    GAMG    1.81844850e-04    1.50381060e-06    10    true
23                  DILUPBiCGStab    6.77782630e-02    2.50757110e-04    1    1.48653250e-02    5.21972350e-05    1    false    GAMG    1.72173430e-04    1.45175550e-06    10    true
24                  DILUPBiCGStab    6.53140050e-02    2.41670020e-04    1    1.41437450e-02    4.99757360e-05    1    false    GAMG    1.73370400e-04    1.46278090e-06    10    true
25                  DILUPBiCGStab    6.30025590e-02    2.32989500e-04    1    1.34863160e-02    4.79381780e-05    1    false    GAMG    1.71632110e-04    1.44063250e-06    10    true
26                  DILUPBiCGStab    6.08374200e-02    2.24776930e-04    1    1.28970280e-02    4.60580520e-05    1    false    GAMG    1.79620720e-04    1.48070940e-06    10    true
27                  DILUPBiCGStab    5.87925880e-02    2.16906900e-04    1    1.23541050e-02    4.43544230e-05    1    false    GAMG    1.78122980e-04    1.47343430e-06    10    true
28                  DILUPBiCGStab    5.68701380e-02    2.09467830e-04    1    1.18693010e-02    4.27715320e-05    1    false    GAMG    1.92241980e-04    1.55318520e-06    10    true
29                  DILUPBiCGStab    5.50387110e-02    2.02284800e-04    1    1.14108410e-02    4.13368420e-05    1    false    GAMG    1.83502800e-04    1.52036720e-06    10    true
30                  DILUPBiCGStab    5.33225160e-02    1.95563590e-04    1    1.10138510e-02    3.99818580e-05    1    false    GAMG    2.19881880e-04    1.69307790e-06    10    true
31                  DILUPBiCGStab    5.16611490e-02    1.88944310e-04    1    1.06115980e-02    3.87271670e-05    1    false    GAMG    1.94226080e-04    1.05166710e-06    9    true
32                  DILUPBiCGStab    5.01307010e-02    1.82932710e-04    1    1.03014500e-02    3.75655170e-05    1    false    GAMG    2.83234270e-04    2.64408350e-06    9    true
33                  DILUPBiCGStab    4.85968080e-02    1.76766330e-04    1    9.92182590e-03    3.64379860e-05    1    false    GAMG    2.07138410e-04    1.01193740e-06    11    true
34                  DILUPBiCGStab    4.72464770e-02    1.71468870e-04    1    9.69155610e-03    3.55057620e-05    1    false    GAMG    3.93283910e-04    3.05400540e-06    9    true
35                  DILUPBiCGStab    4.58148180e-02    1.65662860e-04    1    9.31109310e-03    3.43954260e-05    1    false    GAMG    2.28560780e-04    1.92363650e-06    11    true
36                  DILUPBiCGStab    4.45977370e-02    1.60842140e-04    1    9.16470370e-03    3.39266820e-05    1    false    GAMG    4.28370440e-04    3.43084120e-06    9    true
37                  DILUPBiCGStab    4.32852850e-02    1.55414630e-04    1    8.82190370e-03    3.25834400e-05    1    false    GAMG    2.43366240e-04    1.66772150e-06    11    true
38                  DILUPBiCGStab    4.21815780e-02    1.51078060e-04    1    8.64352460e-03    3.19734930e-05    1    false    GAMG    4.77693940e-04    3.41435100e-06    9    true
39                  DILUPBiCGStab    4.09662000e-02    1.46093860e-04    1    8.34459010e-03    3.09677080e-05    1    false    GAMG    2.72134740e-04    2.10972370e-06    11    true
40                  DILUPBiCGStab    3.99430810e-02    1.42052270e-04    1    8.22838910e-03    3.06635910e-05    1    false    GAMG    4.75725740e-04    3.50940940e-06    9    true

I've attached my residuals log for the first 40 iterations. I notice that U_converged is always false, all the way, while p_converged is showing true.

I don't know if it's a problem with my boundary conditions, mesh or system properties. I've been breaking my head with this for a while. Can someone please help me out? I'd really appreciate it.
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Old   February 3, 2020, 10:57
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Petros Ampatzidis
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Hi Vignesh,

I am faced with a similar issue. I am running simpleFoam and although SIMPLE solution seems to converge before reaching the dedicated number of iterations, U_converged is always False in the residuals file.

Have you found any solution to your problem?

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Old   July 7, 2020, 20:43
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Daniel
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Did anyone face a similar problem and found a solution? Or know about a similar (solved) thread?



Quote:
Originally Posted by vignesh_sr View Post
Hello everyone,

I notice that U_converged is always false, all the way, while p_converged is showing true.
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Old   July 18, 2020, 08:21
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Quote:
Originally Posted by vignesh_sr View Post
I'm getting some pretty weird results, and I'm not able to validate my pressure and velocity plots with the literature.

Code:

# Solver information
# Time              U_solver            Ux_initial          Ux_final            Ux_iters            Uy_initial          Uy_final            Uy_iters            U_converged         p_solver            p_initial           p_final             p_iters             p_converged     
1                   DILUPBiCGStab    1.00000000e+00    5.63145200e-03    1    1.00000000e+00    1.18017460e-03    1    false    GAMG    1.00000000e+00    3.08416040e-03    1    true
2                   DILUPBiCGStab    5.45963700e-01    1.69905430e-03    1    3.80739180e-01    1.41675240e-03    1    false    GAMG    2.26367420e-01    1.35376850e-03    3    true
3                   DILUPBiCGStab    4.30959060e-01    1.18852260e-03    1    2.92858160e-01    9.58617740e-04    1    false    GAMG    5.43492460e-02    3.31423630e-04    5    true
4                   DILUPBiCGStab    3.20779760e-01    8.65311860e-04    1    3.13826670e-01    9.23813840e-04    1    false    GAMG    1.69414160e-02    1.34136910e-04    5    true
5                   DILUPBiCGStab    2.56209780e-01    6.71257920e-04    1    1.71144620e-01    1.22977570e-03    1    false    GAMG    1.21129840e-02    1.03227820e-04    7    true
6                   DILUPBiCGStab    2.17978780e-01    6.08204110e-04    1    9.04764450e-02    7.59603610e-04    1    false    GAMG    6.80493660e-03    3.89629250e-05    9    true
7                   DILUPBiCGStab    1.88510680e-01    5.48296570e-04    1    5.44852170e-02    5.07802030e-04    1    false    GAMG    3.11672060e-03    1.45205410e-05    8    true
8                   DILUPBiCGStab    1.65910160e-01    5.03121960e-04    1    5.41494690e-02    2.58120990e-04    1    false    GAMG    1.78527080e-03    1.27787290e-05    10    true
9                   DILUPBiCGStab    1.48527580e-01    4.63248670e-04    1    5.09946720e-02    1.67642980e-04    1    false    GAMG    1.64403040e-03    1.33992420e-05    7    true
10                  DILUPBiCGStab    1.35567040e-01    4.37185820e-04    1    4.29566890e-02    1.33335920e-04    1    false    GAMG    1.14007820e-03    5.09410220e-06    9    true
11                  DILUPBiCGStab    1.25101200e-01    4.15358040e-04    1    3.67467390e-02    1.16270810e-04    1    false    GAMG    6.55856160e-04    5.55730280e-06    10    true
12                  DILUPBiCGStab    1.16331370e-01    3.94785310e-04    1    3.33904360e-02    1.14179040e-04    1    false    GAMG    4.08227720e-04    2.61137050e-06    10    true
13                  DILUPBiCGStab    1.08920730e-01    3.77537340e-04    1    3.04151770e-02    1.00107160e-04    1    false    GAMG    3.19891450e-04    1.40731650e-06    10    true
14                  DILUPBiCGStab    1.02434070e-01    3.60374460e-04    1    2.76140780e-02    8.70842780e-05    1    false    GAMG    3.38320430e-04    2.80018250e-06    8    true
15                  DILUPBiCGStab    9.68027690e-02    3.45042220e-04    1    2.51560640e-02    7.97026030e-05    1    false    GAMG    2.95921630e-04    2.04757530e-06    10    true
16                  DILUPBiCGStab    9.18175200e-02    3.30619640e-04    1    2.31945540e-02    7.53207720e-05    1    false    GAMG    2.78887010e-04    2.13555550e-06    10    true
17                  DILUPBiCGStab    8.73560160e-02    3.17040200e-04    1    2.14896960e-02    7.10223110e-05    1    false    GAMG    2.61539370e-04    1.78062630e-06    10    true
18                  DILUPBiCGStab    8.33385690e-02    3.04377940e-04    1    2.00176410e-02    6.69856460e-05    1    false    GAMG    2.39387170e-04    1.52502490e-06    10    true
19                  DILUPBiCGStab    7.96829250e-02    2.92397810e-04    1    1.87329790e-02    6.35358290e-05    1    false    GAMG    2.24885040e-04    1.49790800e-06    10    true
20                  DILUPBiCGStab    7.63413040e-02    2.81126890e-04    1    1.75887980e-02    6.02910410e-05    1    false    GAMG    2.10218520e-04    1.53493880e-06    10    true
21                  DILUPBiCGStab    7.32650410e-02    2.70438530e-04    1    1.65726370e-02    5.73083060e-05    1    false    GAMG    1.91872990e-04    1.52267420e-06    10    true
22                  DILUPBiCGStab    7.04232370e-02    2.60365690e-04    1    1.56758180e-02    5.46103790e-05    1    false    GAMG    1.81844850e-04    1.50381060e-06    10    true
23                  DILUPBiCGStab    6.77782630e-02    2.50757110e-04    1    1.48653250e-02    5.21972350e-05    1    false    GAMG    1.72173430e-04    1.45175550e-06    10    true
24                  DILUPBiCGStab    6.53140050e-02    2.41670020e-04    1    1.41437450e-02    4.99757360e-05    1    false    GAMG    1.73370400e-04    1.46278090e-06    10    true
25                  DILUPBiCGStab    6.30025590e-02    2.32989500e-04    1    1.34863160e-02    4.79381780e-05    1    false    GAMG    1.71632110e-04    1.44063250e-06    10    true
26                  DILUPBiCGStab    6.08374200e-02    2.24776930e-04    1    1.28970280e-02    4.60580520e-05    1    false    GAMG    1.79620720e-04    1.48070940e-06    10    true
27                  DILUPBiCGStab    5.87925880e-02    2.16906900e-04    1    1.23541050e-02    4.43544230e-05    1    false    GAMG    1.78122980e-04    1.47343430e-06    10    true
28                  DILUPBiCGStab    5.68701380e-02    2.09467830e-04    1    1.18693010e-02    4.27715320e-05    1    false    GAMG    1.92241980e-04    1.55318520e-06    10    true
29                  DILUPBiCGStab    5.50387110e-02    2.02284800e-04    1    1.14108410e-02    4.13368420e-05    1    false    GAMG    1.83502800e-04    1.52036720e-06    10    true
30                  DILUPBiCGStab    5.33225160e-02    1.95563590e-04    1    1.10138510e-02    3.99818580e-05    1    false    GAMG    2.19881880e-04    1.69307790e-06    10    true
31                  DILUPBiCGStab    5.16611490e-02    1.88944310e-04    1    1.06115980e-02    3.87271670e-05    1    false    GAMG    1.94226080e-04    1.05166710e-06    9    true
32                  DILUPBiCGStab    5.01307010e-02    1.82932710e-04    1    1.03014500e-02    3.75655170e-05    1    false    GAMG    2.83234270e-04    2.64408350e-06    9    true
33                  DILUPBiCGStab    4.85968080e-02    1.76766330e-04    1    9.92182590e-03    3.64379860e-05    1    false    GAMG    2.07138410e-04    1.01193740e-06    11    true
34                  DILUPBiCGStab    4.72464770e-02    1.71468870e-04    1    9.69155610e-03    3.55057620e-05    1    false    GAMG    3.93283910e-04    3.05400540e-06    9    true
35                  DILUPBiCGStab    4.58148180e-02    1.65662860e-04    1    9.31109310e-03    3.43954260e-05    1    false    GAMG    2.28560780e-04    1.92363650e-06    11    true
36                  DILUPBiCGStab    4.45977370e-02    1.60842140e-04    1    9.16470370e-03    3.39266820e-05    1    false    GAMG    4.28370440e-04    3.43084120e-06    9    true
37                  DILUPBiCGStab    4.32852850e-02    1.55414630e-04    1    8.82190370e-03    3.25834400e-05    1    false    GAMG    2.43366240e-04    1.66772150e-06    11    true
38                  DILUPBiCGStab    4.21815780e-02    1.51078060e-04    1    8.64352460e-03    3.19734930e-05    1    false    GAMG    4.77693940e-04    3.41435100e-06    9    true
39                  DILUPBiCGStab    4.09662000e-02    1.46093860e-04    1    8.34459010e-03    3.09677080e-05    1    false    GAMG    2.72134740e-04    2.10972370e-06    11    true
40                  DILUPBiCGStab    3.99430810e-02    1.42052270e-04    1    8.22838910e-03    3.06635910e-05    1    false    GAMG    4.75725740e-04    3.50940940e-06    9    true

I am not sure why you ask this and I believe it is the reason that you mis-understand things here. All your quantities for Ux, Uy and Uz are larger than 1e-4.

Code:
Ux = 3.99e-2
Uy = 8.22e-3
Uz = empty
It is not important to have the »final« guy on a extreme minimum level as we do have explicit parts which has to be converged too. Regarding your »p« field, this seems to be wired, yes. How did you get the boolean operations that you show? A test-case is always much better than some text
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Old   February 10, 2021, 15:14
Default U_converged = false
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Benjamin Norris
Join Date: Oct 2020
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Hi Tobi et al.,

Apologies to hijack this thread, but I am having the same issue with my interFoam model. The model simulates a wave train across a rough bottom. My model uses the k-epsilon turbulence closure scheme and I have set the fvSolutions to what I think are tight tolerances for pressure, velocity, and turbulence.

When I check the residuals, I am also seeing U_converged = false for all timesteps, while the other parameters (p_rgh, k, epsilon) = true. The initial values for Ux and Uz are O(10^-4) and final values O(10^-10). I think (?) these values are appropriate, but I am still an OpenFOAM beginner and have much to learn.

I have attached my case as a zip file, and a subset of the residuals (between timesteps 74 and 74.25 s) are below. Please note my case does not include the mesh because it is too large to upload to this forum. I do not think my issue is related to the mesh as checkMesh returns "ok" for all fields.

Thank you.

Ben

Code:
# Solver information
# Time        	U_solver      	Ux_initial    	Ux_final      	Ux_iters      	Uz_initial    	Uz_final      	Uz_iters      	U_converged   	k_solver      	k_initial     	k_final       	k_iters       	k_converged   	p_rgh_solver  	p_rgh_initial 	p_rgh_final   	p_rgh_iters   	p_rgh_converged	epsilon_solver	epsilon_initial	epsilon_final 	epsilon_iters 	epsilon_converged
74            	DILUPBiCGStab	4.006390e-04	1.671520e-09	1	1.256120e-03	4.949610e-09	1	false	DILUPBiCGStab	1.073630e-03	2.223450e-09	1	true	DICPCG	2.547670e-03	9.928240e-07	97	true	DILUPBiCGStab	1.509320e-03	2.957190e-09	1	true
74.0078       	DILUPBiCGStab	3.675810e-04	1.131180e-09	1	1.186660e-03	3.313750e-09	1	false	DILUPBiCGStab	9.478730e-04	1.447630e-09	1	true	DICPCG	2.815580e-03	9.289800e-07	99	true	DILUPBiCGStab	1.335080e-03	1.985770e-09	1	true
74.0156       	DILUPBiCGStab	3.668450e-04	1.132490e-09	1	1.180980e-03	3.317960e-09	1	false	DILUPBiCGStab	9.483030e-04	1.464180e-09	1	true	DICPCG	2.830190e-03	9.412030e-07	99	true	DILUPBiCGStab	1.340930e-03	1.957330e-09	1	true
74.0234       	DILUPBiCGStab	3.665610e-04	1.135770e-09	1	1.179020e-03	3.361480e-09	1	false	DILUPBiCGStab	9.490000e-04	1.468220e-09	1	true	DICPCG	2.845550e-03	9.390510e-07	99	true	DILUPBiCGStab	1.347280e-03	1.982700e-09	1	true
74.0312       	DILUPBiCGStab	3.660440e-04	1.141450e-09	1	1.178930e-03	3.456610e-09	1	false	DILUPBiCGStab	9.497780e-04	1.478040e-09	1	true	DICPCG	2.860480e-03	9.420370e-07	99	true	DILUPBiCGStab	1.353560e-03	2.001070e-09	1	true
74.0391       	DILUPBiCGStab	3.659540e-04	1.142890e-09	1	1.178020e-03	3.431430e-09	1	false	DILUPBiCGStab	9.509160e-04	1.490620e-09	1	true	DICPCG	2.876190e-03	9.454020e-07	99	true	DILUPBiCGStab	1.359840e-03	1.989490e-09	1	true
74.0469       	DILUPBiCGStab	3.659140e-04	1.144960e-09	1	1.175950e-03	3.434170e-09	1	false	DILUPBiCGStab	9.512020e-04	1.507280e-09	1	true	DICPCG	2.892380e-03	9.479810e-07	99	true	DILUPBiCGStab	1.365800e-03	1.982210e-09	1	true
74.0547       	DILUPBiCGStab	3.653190e-04	1.144550e-09	1	1.176260e-03	3.372510e-09	1	false	DILUPBiCGStab	9.518550e-04	1.529590e-09	1	true	DICPCG	2.908370e-03	9.511380e-07	99	true	DILUPBiCGStab	1.371740e-03	1.971270e-09	1	true
74.0625       	DILUPBiCGStab	3.653970e-04	1.144830e-09	1	1.171660e-03	3.349070e-09	1	false	DILUPBiCGStab	9.527360e-04	1.544620e-09	1	true	DICPCG	2.926000e-03	9.579410e-07	99	true	DILUPBiCGStab	1.377870e-03	1.947170e-09	1	true
74.0703       	DILUPBiCGStab	3.649560e-04	1.148800e-09	1	1.172070e-03	3.391810e-09	1	false	DILUPBiCGStab	9.533970e-04	1.564550e-09	1	true	DICPCG	2.943060e-03	9.605520e-07	99	true	DILUPBiCGStab	1.384170e-03	1.929200e-09	1	true
74.0771       	DILUPBiCGStab	3.347940e-04	7.702510e-10	1	1.111930e-03	2.289350e-09	1	false	DILUPBiCGStab	8.366920e-04	9.786550e-10	1	true	DICPCG	3.296090e-03	9.393230e-07	101	true	DILUPBiCGStab	1.216480e-03	1.284080e-09	1	true
74.084        	DILUPBiCGStab	3.340760e-04	7.755790e-10	1	1.106820e-03	2.312830e-09	1	false	DILUPBiCGStab	8.373840e-04	9.887800e-10	1	true	DICPCG	3.312030e-03	9.217870e-07	101	true	DILUPBiCGStab	1.220410e-03	1.272920e-09	1	true
74.0908       	DILUPBiCGStab	3.336870e-04	7.737800e-10	1	1.106140e-03	2.216780e-09	1	false	DILUPBiCGStab	8.378130e-04	1.002850e-09	1	true	DICPCG	3.327590e-03	9.159130e-07	101	true	DILUPBiCGStab	1.224260e-03	1.264000e-09	1	true
74.0977       	DILUPBiCGStab	3.332820e-04	7.764860e-10	1	1.103290e-03	2.220500e-09	1	false	DILUPBiCGStab	8.383610e-04	1.011400e-09	1	true	DICPCG	3.343770e-03	9.146800e-07	101	true	DILUPBiCGStab	1.228140e-03	1.251800e-09	1	true
74.1045       	DILUPBiCGStab	3.328540e-04	7.782340e-10	1	1.103420e-03	2.223400e-09	1	false	DILUPBiCGStab	8.385670e-04	1.027800e-09	1	true	DICPCG	3.360250e-03	9.172290e-07	101	true	DILUPBiCGStab	1.231930e-03	1.244180e-09	1	true
74.1113       	DILUPBiCGStab	3.327080e-04	7.779960e-10	1	1.101150e-03	2.195090e-09	1	false	DILUPBiCGStab	8.389420e-04	1.045750e-09	1	true	DICPCG	3.377620e-03	9.121430e-07	101	true	DILUPBiCGStab	1.235520e-03	1.239760e-09	1	true
74.1182       	DILUPBiCGStab	3.322000e-04	7.798310e-10	1	1.100970e-03	2.194550e-09	1	false	DILUPBiCGStab	8.392080e-04	1.055850e-09	1	true	DICPCG	3.394440e-03	8.984390e-07	101	true	DILUPBiCGStab	1.239010e-03	1.228510e-09	1	true
74.125        	DILUPBiCGStab	3.320890e-04	7.820510e-10	1	1.100670e-03	2.186770e-09	1	false	DILUPBiCGStab	8.397360e-04	1.066090e-09	1	true	DICPCG	3.413100e-03	9.991530e-07	100	true	DILUPBiCGStab	1.242330e-03	1.218330e-09	1	true
74.1319       	DILUPBiCGStab	3.353430e-04	8.229510e-10	1	1.104640e-03	2.288990e-09	1	false	DILUPBiCGStab	8.531190e-04	1.142360e-09	1	true	DICPCG	3.387290e-03	9.689490e-07	100	true	DILUPBiCGStab	1.265160e-03	1.266340e-09	1	true
74.1389       	DILUPBiCGStab	3.350330e-04	8.278180e-10	1	1.104040e-03	2.298910e-09	1	false	DILUPBiCGStab	8.532030e-04	1.155770e-09	1	true	DICPCG	3.406550e-03	9.633850e-07	100	true	DILUPBiCGStab	1.268200e-03	1.253300e-09	1	true
74.1458       	DILUPBiCGStab	3.349180e-04	8.313580e-10	1	1.101420e-03	2.297410e-09	1	false	DILUPBiCGStab	8.532190e-04	1.172850e-09	1	true	DICPCG	3.427010e-03	9.628180e-07	100	true	DILUPBiCGStab	1.270850e-03	1.240410e-09	1	true
74.1528       	DILUPBiCGStab	3.345940e-04	8.339030e-10	1	1.100810e-03	2.319730e-09	1	false	DILUPBiCGStab	8.536660e-04	1.192870e-09	1	true	DICPCG	3.446500e-03	9.684660e-07	100	true	DILUPBiCGStab	1.273410e-03	1.228900e-09	1	true
74.1593       	DILUPBiCGStab	3.203330e-04	6.804190e-10	1	1.070920e-03	1.891990e-09	1	false	DILUPBiCGStab	7.976560e-04	9.301900e-10	1	true	DICPCG	3.673590e-03	9.381040e-07	101	true	DILUPBiCGStab	1.191260e-03	9.862140e-10	1	true
74.1657       	DILUPBiCGStab	3.204180e-04	6.821850e-10	1	1.067000e-03	1.885890e-09	1	false	DILUPBiCGStab	7.984470e-04	9.402180e-10	1	true	DICPCG	3.692980e-03	9.364430e-07	101	true	DILUPBiCGStab	1.194080e-03	9.694410e-10	1	true
74.1722       	DILUPBiCGStab	3.197700e-04	6.841930e-10	1	1.066180e-03	1.883800e-09	1	false	DILUPBiCGStab	7.984390e-04	9.475690e-10	1	true	DICPCG	3.711180e-03	9.510730e-07	101	true	DILUPBiCGStab	1.195660e-03	9.586410e-10	1	true
74.1787       	DILUPBiCGStab	3.199420e-04	6.867710e-10	1	1.064600e-03	1.904370e-09	1	false	DILUPBiCGStab	7.995010e-04	9.493260e-10	1	true	DICPCG	3.731820e-03	9.656830e-07	101	true	DILUPBiCGStab	1.198060e-03	9.466950e-10	1	true
74.1852       	DILUPBiCGStab	3.194780e-04	6.895830e-10	1	1.063310e-03	1.921970e-09	1	false	DILUPBiCGStab	8.002090e-04	9.330530e-10	1	true	DICPCG	3.750980e-03	9.899740e-07	101	true	DILUPBiCGStab	1.199810e-03	9.310270e-10	1	true
74.1917       	DILUPBiCGStab	3.194320e-04	6.921130e-10	1	1.063340e-03	1.931700e-09	1	false	DILUPBiCGStab	8.002920e-04	9.400920e-10	1	true	DICPCG	3.771640e-03	9.938730e-07	101	true	DILUPBiCGStab	1.200870e-03	9.139940e-10	1	true
74.1981       	DILUPBiCGStab	3.194180e-04	6.953000e-10	1	1.060560e-03	1.938390e-09	1	false	DILUPBiCGStab	8.009430e-04	9.412560e-10	1	true	DICPCG	3.792370e-03	9.927820e-07	101	true	DILUPBiCGStab	1.202940e-03	9.092870e-10	1	true
74.2046       	DILUPBiCGStab	3.189950e-04	6.971790e-10	1	1.061010e-03	1.937030e-09	1	false	DILUPBiCGStab	8.016590e-04	9.425830e-10	1	true	DICPCG	3.813560e-03	9.747890e-07	101	true	DILUPBiCGStab	1.205390e-03	8.899870e-10	1	true
74.2111       	DILUPBiCGStab	3.190290e-04	6.997840e-10	1	1.058620e-03	1.941140e-09	1	false	DILUPBiCGStab	8.024820e-04	9.443380e-10	1	true	DICPCG	3.834910e-03	9.552270e-07	101	true	DILUPBiCGStab	1.207820e-03	8.702000e-10	1	true
74.2176       	DILUPBiCGStab	3.186930e-04	7.014400e-10	1	1.060100e-03	1.941760e-09	1	false	DILUPBiCGStab	8.029270e-04	9.444550e-10	1	true	DICPCG	3.856600e-03	9.510220e-07	101	true	DILUPBiCGStab	1.210220e-03	8.509680e-10	1	true
74.2241       	DILUPBiCGStab	3.184910e-04	7.031740e-10	1	1.059660e-03	1.942760e-09	1	false	DILUPBiCGStab	8.033520e-04	9.453160e-10	1	true	DICPCG	3.879160e-03	9.501790e-07	101	true	DILUPBiCGStab	1.212510e-03	8.418080e-10	1	true
74.2306       	DILUPBiCGStab	3.186290e-04	7.052020e-10	1	1.056830e-03	1.943750e-09	1	false	DILUPBiCGStab	8.042540e-04	9.453210e-10	1	true	DICPCG	3.902040e-03	9.557760e-07	101	true	DILUPBiCGStab	1.215020e-03	8.363900e-10	1	true
74.237        	DILUPBiCGStab	3.180920e-04	7.070520e-10	1	1.058550e-03	1.945430e-09	1	false	DILUPBiCGStab	8.052120e-04	9.448860e-10	1	true	DICPCG	3.925490e-03	9.498730e-07	101	true	DILUPBiCGStab	1.217810e-03	8.338450e-10	1	true
74.2435       	DILUPBiCGStab	2.231170e-04	4.982210e-10	1	7.489500e-04	1.303840e-09	1	false	DILUPBiCGStab	8.064960e-04	9.430960e-10	1	true	DICPCG	3.861300e-03	9.689160e-07	100	true	DILUPBiCGStab	1.220680e-03	8.260530e-10	1	true
74.25         	DILUPBiCGStab	2.233570e-04	5.020770e-10	1	7.468910e-04	1.309890e-09	1	false	DILUPBiCGStab	8.075350e-04	9.421010e-10	1	true	DICPCG	3.885940e-03	9.699520e-07	100	true	DILUPBiCGStab	1.223710e-03	8.177950e-10	1	true
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Old   March 6, 2024, 03:09
Default U_converged is all false
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Zhang Xuan
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I also have the same problem.
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Old   June 30, 2024, 01:46
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Hello everyone,


It seems this thread is still open and not resolved. I am facing the same issue. I implemented the below snippet in the function object in OpenFOAM ESI version.

solverInfo
{
type solverInfo;
libs ("libutilityFunctionObjects.so");
fields (U p k epsilon);
writeResidualFields no;
executeControl timeStep;
executeInterval 10;
}

Here is my output, where "U_converged" results in "FALSE", where p, k, and epsilon shows convergence.

#Time U_solver Ux_initial Ux_final Ux_iters Uy_initial Uy_final Uy_iters Uz_initial Uz_final Uz_iters U_converged k_solver k_initial k_final k_iters k_converged p_solver p_initial p_final p_iters p_converged epsilon_solver epsilon_initial epsilon_final epsilon_iters epsilon_converged
1.20E-08 smoothSolver 3.70E-05 4.68E-17 15 3.71E-05 4.72E-17 15 1.62E-06 2.49E-17 15 FALSE smoothSolver 1.00E+00 3.57E-12 15 TRUE GAMG 1.00E+00 8.07E-04 13 TRUE smoothSolver 9.84E-06 8.04E-19 15 TRUE
2.64E-08 smoothSolver 1.86E-03 5.01E-17 15 1.85E-03 5.04E-17 15 8.22E-05 2.37E-17 15 FALSE smoothSolver 6.46E-03 1.61E-14 15 TRUE GAMG 1.81E-01 1.62E-04 13 TRUE smoothSolver 7.43E-06 4.49E-19 15 TRUE

I tried checking parameters in fvOptions for solution convergence, but no success.
Can someone help me out here ? Thank you
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