periodic box simulation tutorial

tutorials/cfdemSolverPimple/PeriodicBox/Allrun.sh

@@ -0,0 +1,31 @@
+#!/bin/bash
+#------------------------------------------------------------------------------
+# allrun script for periodic box test case
+# run periodic box
+# Behrad Esgandari - August 2023
+#------------------------------------------------------------------------------
+
+#- define variables
+casePath="$(dirname "$(readlink -f ${BASH_SOURCE[0]})")"
+
+#- include functions
+source $CFDEM_PROJECT_DIR/etc/functions.sh
+
+# check if mesh was built
+if [ -f "$casePath/CFD/constant/polyMesh/points" ]; then
+    echo "mesh was built before - using old mesh"
+else
+    echo "mesh needs to be built"
+    cd $casePath/CFD
+    blockMesh
+fi
+
+if [ -f "$casePath/DEM/post/restart/liggghts.restart" ];  then
+    echo "LIGGGHTS init was run before - using existing restart file"
+else
+    #- run serial DEM
+    $casePath/parDEMrun.sh
+fi
+
+#- run parallel CFD-DEM
+bash $casePath/parCFDDEMrun.sh

tutorials/cfdemSolverPimple/PeriodicBox/CFD/0/Ksl

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+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     | Website:  https://openfoam.org
+    \\  /    A nd           | Version:  6
+     \\/     M anipulation  |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    version     2.0;
+    format      ascii;
+    class       volScalarField;
+    object      Ksl;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+dimensions      [1 -3 -1 0 0 0 0];
+
+internalField   uniform 0;
+
+boundaryField
+{
+    bottom
+    {
+        type            cyclic;
+    }
+    
+    top
+    {
+        type            cyclic;
+    }
+    
+    lr1
+    {
+        type            cyclic;
+    }
+    
+    lr2
+    {
+        type            cyclic;
+    }
+    
+    vh1
+    {
+        type            cyclic;
+    }
+    
+    vh2
+    {
+        type            cyclic;
+    }
+}
+
+// ************************************************************************* //

tutorials/cfdemSolverPimple/PeriodicBox/CFD/0/T

@@ -0,0 +1,54 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+| =========                 |                                                 |
+| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
+|  \\    /   O peration     | Version:  1.6                                   |
+|   \\  /    A nd           | Web:      http://www.OpenFOAM.org               |
+|    \\/     M anipulation  |                                                 |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    version     2.0;
+    format      ascii;
+    class       volScalarField;
+    object      T;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+dimensions      [0 0 0 1 0 0 0];
+
+internalField   uniform 293;
+
+boundaryField
+{
+    bottom
+    {
+        type            cyclic;
+    }
+    
+    top
+    {
+        type            cyclic;
+    }
+    
+    lr1
+    {
+        type            cyclic;
+    }
+    
+    lr2
+    {
+        type            cyclic;
+    }
+    
+    vh1
+    {
+        type            cyclic;
+    }
+    
+    vh2
+    {
+        type            cyclic;
+    }
+}
+
+// ************************************************************************* //

tutorials/cfdemSolverPimple/PeriodicBox/CFD/0/U

@@ -0,0 +1,54 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     | Website:  https://openfoam.org
+    \\  /    A nd           | Version:  6
+     \\/     M anipulation  |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    version     2.0;
+    format      ascii;
+    class       volVectorField;
+    object      U;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+dimensions      [0 1 -1 0 0 0 0];
+
+internalField   uniform (0 0 0);
+
+boundaryField
+{
+    bottom
+    {
+        type            cyclic;
+    }
+    
+    top
+    {
+        type            cyclic;
+    }
+    
+    lr1
+    {
+        type            cyclic;
+    }
+    
+    lr2
+    {
+        type            cyclic;
+    }
+    
+    vh1
+    {
+        type            cyclic;
+    }
+    
+    vh2
+    {
+        type            cyclic;
+    }
+}
+
+// ************************************************************************* //

tutorials/cfdemSolverPimple/PeriodicBox/CFD/0/Us

@@ -0,0 +1,54 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     | Website:  https://openfoam.org
+    \\  /    A nd           | Version:  6
+     \\/     M anipulation  |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    version     2.0;
+    format      ascii;
+    class       volVectorField;
+    object      Us;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+dimensions      [0 1 -1 0 0 0 0];
+
+internalField   uniform (0 0 0);
+
+boundaryField
+{
+    bottom
+    {
+        type            cyclic;
+    }
+    
+    top
+    {
+        type            cyclic;
+    }
+    
+    lr1
+    {
+        type            cyclic;
+    }
+    
+    lr2
+    {
+        type            cyclic;
+    }
+    
+    vh1
+    {
+        type            cyclic;
+    }
+    
+    vh2
+    {
+        type            cyclic;
+    }
+}
+
+// ************************************************************************* //

tutorials/cfdemSolverPimple/PeriodicBox/CFD/0/p

@@ -0,0 +1,54 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     | Website:  https://openfoam.org
+    \\  /    A nd           | Version:  6
+     \\/     M anipulation  |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    version     2.0;
+    format      ascii;
+    class       volScalarField;
+    object      p;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+dimensions      [0 2 -2 0 0 0 0];
+
+internalField   uniform 1e5;
+
+boundaryField
+{
+    bottom
+    {
+        type            cyclic;
+    }
+    
+    top
+    {
+        type            cyclic;
+    }
+    
+    lr1
+    {
+        type            cyclic;
+    }
+    
+    lr2
+    {
+        type            cyclic;
+    }
+    
+    vh1
+    {
+        type            cyclic;
+    }
+    
+    vh2
+    {
+        type            cyclic;
+    }
+}
+
+// ************************************************************************* //

tutorials/cfdemSolverPimple/PeriodicBox/CFD/0/rho

@@ -0,0 +1,54 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     | Website:  https://openfoam.org
+    \\  /    A nd           | Version:  6
+     \\/     M anipulation  |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    version     2.0;
+    format      ascii;
+    class       volScalarField;
+    object      rho;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+dimensions      [1 -3 0 0 0 0 0];
+
+internalField   uniform 1.3;
+
+boundaryField
+{
+    bottom
+    {
+        type            cyclic;
+    }
+    
+    top
+    {
+        type            cyclic;
+    }
+    
+    lr1
+    {
+        type            cyclic;
+    }
+    
+    lr2
+    {
+        type            cyclic;
+    }
+    
+    vh1
+    {
+        type            cyclic;
+    }
+    
+    vh2
+    {
+        type            cyclic;
+    }
+}
+
+// ************************************************************************* //

tutorials/cfdemSolverPimple/PeriodicBox/CFD/0/sSmoothField

@@ -0,0 +1,56 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+| =========                 |                                                 |
+| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
+|  \\    /   O peration     | Version:  1.6                                   |
+|   \\  /    A nd           | Web:      www.OpenFOAM.org                      |
+|    \\/     M anipulation  |                                                 |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    version     2.0;
+    format      ascii;
+    class       volScalarField;
+    location    "0";
+    object      sSmoothField;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+dimensions      [0 0 0 0 0 0 0];
+
+internalField   uniform 1;
+
+boundaryField
+{
+    bottom
+    {
+        type            cyclic;
+    }
+    
+    top
+    {
+        type            cyclic;
+    }
+    
+    lr1
+    {
+        type            cyclic;
+    }
+    
+    lr2
+    {
+        type            cyclic;
+    }
+    
+    vh1
+    {
+        type            cyclic;
+    }
+    
+    vh2
+    {
+        type            cyclic;
+    }
+}
+
+
+// ************************************************************************* //

tutorials/cfdemSolverPimple/PeriodicBox/CFD/0/vSmoothField

@@ -0,0 +1,56 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+| =========                 |                                                 |
+| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
+|  \\    /   O peration     | Version:  1.6                                   |
+|   \\  /    A nd           | Web:      www.OpenFOAM.org                      |
+|    \\/     M anipulation  |                                                 |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    version     2.0;
+    format      ascii;
+    class       volVectorField;
+    location    "0";
+    object      vSmoothField;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+dimensions      [0 0 0 0 0 0 0];
+
+internalField   uniform (0 0 0);
+
+boundaryField
+{
+    bottom
+    {
+        type            cyclic;
+    }
+    
+    top
+    {
+        type            cyclic;
+    }
+    
+    lr1
+    {
+        type            cyclic;
+    }
+    
+    lr2
+    {
+        type            cyclic;
+    }
+    
+    vh1
+    {
+        type            cyclic;
+    }
+    
+    vh2
+    {
+        type            cyclic;
+    }
+}
+
+
+// ************************************************************************* //

tutorials/cfdemSolverPimple/PeriodicBox/CFD/0/voidfraction

@@ -0,0 +1,54 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     | Website:  https://openfoam.org
+    \\  /    A nd           | Version:  6
+     \\/     M anipulation  |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    version     2.0;
+    format      ascii;
+    class       volScalarField;
+    object      voidfraction;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+dimensions      [0 0 0 0 0 0 0];
+
+internalField   uniform 1;
+
+boundaryField
+{
+    bottom
+    {
+        type            cyclic;
+    }
+    
+    top
+    {
+        type            cyclic;
+    }
+    
+    lr1
+    {
+        type            cyclic;
+    }
+    
+    lr2
+    {
+        type            cyclic;
+    }
+    
+    vh1
+    {
+        type            cyclic;
+    }
+    
+    vh2
+    {
+        type            cyclic;
+    }
+}
+
+// ************************************************************************* //

tutorials/cfdemSolverPimple/PeriodicBox/CFD/constant/couplingProperties

@@ -0,0 +1,157 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     | Website:  https://openfoam.org
+    \\  /    A nd           | Version:  6
+     \\/     M anipulation  |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    version     2.0;
+    format      ascii;
+    class       dictionary;
+    location    "constant";
+    object      couplingProperties;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+// sub-models & settings
+
+syncMode false;
+
+modelType "A";
+
+couplingInterval 50;
+
+voidFractionModel centre;
+
+locateModel engine;
+//locateModel engineSearchMany2Many;
+
+meshMotionModel noMeshMotion;
+
+regionModel allRegion;
+
+IOModel off;
+
+probeModel off;
+
+dataExchangeModel twoWayMPI;
+//dataExchangeModel twoWayOne2One;
+
+averagingModel dense;
+
+clockModel off;
+
+smoothingModel constDiffSmoothing;
+
+forceModels
+(
+    BeetstraDrag
+    gradPForce
+    viscForce
+    staticPressure
+);
+
+otherForceModels
+(
+  gravityEff
+);
+
+momCoupleModels
+(
+    implicitCouple
+);
+
+turbulenceModelType "turbulenceProperties";
+
+
+// sub-model properties
+
+
+engineSearchMany2ManyProps
+{
+    engineProps
+    {
+        treeSearch true;
+    }
+}
+
+twoWayOne2OneProps
+{
+    liggghtsPath "../DEM/in.liggghts_run";
+    verbose true;
+}
+
+
+implicitCoupleProps
+{
+    velFieldName "U";
+    granVelFieldName "Us";
+    voidfractionFieldName "voidfraction";
+}
+
+
+gradPForceProps
+{
+    pFieldName "p";
+    voidfractionFieldName "voidfraction";
+    velocityFieldName "U";
+    interpolation true;
+}
+
+viscForceProps
+{
+    velocityFieldName "U";
+    interpolation true;
+}
+
+BeetstraDragProps
+{
+    velFieldName "U";
+    granVelFieldName "Us";
+    rhoParticle 1500.;
+    voidfractionFieldName "voidfraction";
+    interpolation true;
+}
+
+gravityEffProps
+{
+    voidfractionFieldName "voidfraction";
+    rhoPart 1500;
+}
+
+staticPressureProps
+{
+    rhoGas 1.3; // gas density
+    voidfractionFieldName "voidfraction";
+    rhoPart 1500; //particle density
+    DomainSolidVolumeFraction 0.05; // mass loading
+    g_DEM (0 0 -9.81); //gravity vector compatible with the gravity direction in "g"
+}
+
+constDiffSmoothingProps
+{
+    lowerLimit 0.01;
+    upperLimit 1.0;
+    smoothingLength 0.00025;
+}
+
+
+engineProps
+{
+    treeSearch true;
+}
+
+centreProps
+{
+    alphaMin 0.005;
+    scaleUpVol 1.0;
+}
+
+twoWayMPIProps
+{
+    liggghtsPath "../DEM/in.liggghts_run";
+}
+
+// ************************************************************************* //

tutorials/cfdemSolverPimple/PeriodicBox/CFD/constant/g

@@ -0,0 +1,22 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     | Website:  https://openfoam.org
+    \\  /    A nd           | Version:  6
+     \\/     M anipulation  |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    version     2.0;
+    format      ascii;
+    class       uniformDimensionedVectorField;
+    location    "constant";
+    object      g;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+dimensions      [0 1 -2 0 0 0 0];
+value           ( 0 0 -9.81 );
+
+
+// ************************************************************************* //

tutorials/cfdemSolverPimple/PeriodicBox/CFD/constant/liggghtsCommands

@@ -0,0 +1,31 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     | Website:  https://openfoam.org
+    \\  /    A nd           | Version:  6
+     \\/     M anipulation  |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    version     2.0;
+    format      ascii;
+    class       dictionary;
+    location    "constant";
+    object      liggghtsCommands;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+liggghtsCommandModels
+(
+    runLiggghts
+    writeLiggghts
+);
+
+writeLiggghtsProps
+{
+    writeLast off;
+    writeName "post/restart/liggghts.restartCFDEM";
+    overwrite on;
+}
+
+// ************************************************************************* //

tutorials/cfdemSolverPimple/PeriodicBox/CFD/constant/transportProperties

@@ -0,0 +1,23 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     | Website:  https://openfoam.org
+    \\  /    A nd           | Version:  6
+     \\/     M anipulation  |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    version     2.0;
+    format      ascii;
+    class       dictionary;
+    location    "constant";
+    object      transportProperties;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+transportModel  Newtonian;
+
+nu              [0 2 -1 0 0 0 0] 1.8e-5;
+
+
+// ************************************************************************* //

tutorials/cfdemSolverPimple/PeriodicBox/CFD/constant/turbulenceProperties

@@ -0,0 +1,20 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     | Website:  https://openfoam.org
+    \\  /    A nd           | Version:  6
+     \\/     M anipulation  |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    version     2.0;
+    format      ascii;
+    class       dictionary;
+    location    "constant";
+    object      turbulenceProperties;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+simulationType laminar;
+
+// ************************************************************************* //

tutorials/cfdemSolverPimple/PeriodicBox/CFD/system/blockMeshDict

@@ -0,0 +1,85 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+| =========                 |                                                 |
+| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
+|  \\    /   O peration     | Version:  dev                                   |
+|   \\  /    A nd           | Web:      www.OpenFOAM.org                      |
+|    \\/     M anipulation  |                                                 |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    version     2.0;
+    format      ascii;
+    class       dictionary;
+    object      blockMeshDict;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+convertToMeters 1.0;
+
+vertices 
+(
+    (-0.004 -0.004 -0.016)
+    ( 0.004 -0.004 -0.016)
+    ( 0.004  0.004 -0.016)
+    (-0.004  0.004 -0.016)
+    (-0.004 -0.004  0.016)
+    ( 0.004 -0.004  0.016)
+    ( 0.004  0.004  0.016)
+    (-0.004  0.004  0.016)
+);
+
+blocks
+(
+    hex (0 1 2 3 4 5 6 7) (32 32 128) 
+    simpleGrading (1 1 1)
+);
+
+edges
+(
+);
+
+boundary
+(
+    bottom
+    {
+	type cyclic;
+	neighbourPatch  top;
+        faces	((0 3 2 1));
+    }
+    top
+    {
+	type cyclic;
+	neighbourPatch  bottom;
+        faces	((4 5 6 7));
+    }
+    lr1
+    {
+	type cyclic;
+	neighbourPatch  lr2;
+        faces	((0 3 7 4));
+    }
+    lr2
+    {
+	type cyclic;
+	neighbourPatch  lr1;
+	faces ((1 5 6 2));
+    }
+    vh1
+    {
+	type cyclic;
+	neighbourPatch  vh2;
+        faces ((0 1 4 5));
+    }
+    vh2
+    {
+	type cyclic;
+	neighbourPatch  vh1;
+        faces ((2 6 7 3));
+    }
+);
+
+mergePatchPairs
+(
+);
+
+// ************************************************************************* //

tutorials/cfdemSolverPimple/PeriodicBox/CFD/system/controlDict

@@ -0,0 +1,57 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     | Website:  https://openfoam.org
+    \\  /    A nd           | Version:  6
+     \\/     M anipulation  |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    version     2.0;
+    format      ascii;
+    class       dictionary;
+    location    "system";
+    object      controlDict;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+application     pisoFoam;
+
+startFrom       startTime;
+
+startTime       0;
+
+stopAt          endTime;
+
+endTime         3;
+
+deltaT          0.00005;
+
+writeControl    adjustableRunTime;
+
+writeInterval   0.01;
+
+purgeWrite      0;
+
+writeFormat     ascii;
+
+writePrecision  6;
+
+writeCompression off;
+
+timeFormat      general;
+
+timePrecision   6;
+
+runTimeModifiable true;
+
+adjustTimeStep  no;
+
+maxCo 0.8;
+
+
+functions
+{
+
+}
+// ************************************************************************* //

tutorials/cfdemSolverPimple/PeriodicBox/CFD/system/decomposeParDict

@@ -0,0 +1,28 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     | Website:  https://openfoam.org
+    \\  /    A nd           | Version:  6
+     \\/     M anipulation  |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    version     2.0;
+    format      ascii;
+    class       dictionary;
+    location    "system";
+    object      decomposeParDict;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+numberOfSubdomains  32;
+
+method          simple;
+
+simpleCoeffs
+{
+    n           (8 4 1);
+    delta       0.001;
+}
+
+// ************************************************************************* //

tutorials/cfdemSolverPimple/PeriodicBox/CFD/system/fvSchemes

@@ -0,0 +1,60 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     | Website:  https://openfoam.org
+    \\  /    A nd           | Version:  6
+     \\/     M anipulation  |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    version     2.0;
+    format      ascii;
+    class       dictionary;
+    location    "system";
+    object      fvSchemes;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+ddtSchemes
+{
+    default         backward;//Euler;
+}
+
+gradSchemes
+{
+    default         Gauss linear;
+}
+
+divSchemes
+{
+    default         Gauss linear;
+    div(phi,U)      Gauss limitedLinearV 1;
+    div(phi,k)      Gauss limitedLinear 1;
+    div(phi,epsilon) Gauss limitedLinear 1;
+    div(phi,R)      Gauss limitedLinear 1;
+    div(phi,nuTilda) Gauss limitedLinear 1;
+}
+
+laplacianSchemes
+{
+    default         Gauss linear corrected;
+}
+
+interpolationSchemes
+{
+    default         linear;
+}
+
+snGradSchemes
+{
+    default         corrected;
+}
+
+fluxRequired
+{
+    default         no;
+    p               ;
+}
+
+
+// ************************************************************************* //

tutorials/cfdemSolverPimple/PeriodicBox/CFD/system/fvSolution

@@ -0,0 +1,83 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     | Website:  https://openfoam.org
+    \\  /    A nd           | Version:  6
+     \\/     M anipulation  |
+\*---------------------------------------------------------------------------*/
+FoamFile
+{
+    version     2.0;
+    format      ascii;
+    class       dictionary;
+    location    "system";
+    object      fvSolution;
+}
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+solvers
+{
+    "(p|rho)"
+    {
+        solver          PCG;
+        preconditioner  DIC;
+        tolerance       1e-06;
+        relTol          0.1;
+    }
+
+    "(p|rho)Final"
+    {
+        $p;
+        tolerance       1e-06;
+        relTol          0;
+    }
+
+    "(U|k|e|epsilon|R|nuTilda)"
+    {
+        solver          PBiCG;
+        preconditioner  DILU;
+        tolerance       1e-05;
+        relTol          0;
+    }
+    
+    "(U|e|k|nuTilda)Final"
+    {
+        $U;
+        relTol          0;
+    }
+
+    "(voidfraction|Ksl|UsNext|voidfractionNext|sSmoothField|vSmoothField|fSmooth)"
+    {
+        solver          PCG;
+        preconditioner  DIC;
+        tolerance       1e-05;
+        relTol          0;
+    }
+    
+}
+
+PIMPLE
+{
+    momentumPredictor yes;
+    nOuterCorrectors 6;
+    nCorrectors     2;
+    periodicBoxSwitch yes;
+    nNonOrthogonalCorrectors 0;
+    pRefCell        0;
+    pRefValue       0;
+}
+
+relaxationFactors
+{
+    fields
+    {
+      
+    }
+    equations
+    {
+        "p"  0.3;
+        "U"  0.6;
+    }
+}
+
+// ************************************************************************* //

tutorials/cfdemSolverPimple/PeriodicBox/DEM/in.liggghts_init

@@ -0,0 +1,109 @@
+################################################################################
+# brief: Periodic box - creating particle bed                        		#
+#                                                                              #
+# Periodic box simulations of Geldart A particles (d=0.075mm, rho=1500kg/m3)   #
+# Cf. Radl, S. and Sundaresan, S., A drag model for filtered Euler–Lagrange 	#
+#     simulations of clustered gas–particle suspensions. 			#
+#     Chemical engineering science, (2014).  					#
+# mass loading = 0.05                                                          #
+# authors: Behrad Esgandari                                                    #
+# date: Aug 2023                                                               #
+# copyright: 2023- JKU Linz                                                    #
+################################################################################
+
+echo both
+
+# define the attributes associated with the particles,
+# 'granular' (or 'sphere') style uses diameter, mass and angular velocity
+atom_style      granular
+
+# use an array to map particle IDs to local storage index,
+atom_modify     map array
+
+# set simulation domain to be periodic in x y z
+boundary        p p p
+
+# save communication by turning off Newton's 3rd law for pairwise interaction,
+# note: this setting only influences communication between procs, Newton's
+# 3rd law is still used for contact force calculations
+newton          off
+
+# use a single value for ghost particle cutoff distance and
+# enable velocity to be communicated with ghost particles
+communicate     single vel yes
+
+# set unit system to SI
+units           si
+
+processors      4 2 4
+
+# define the region used as simulation domain (min/max X, min/max Y, min/max Z)
+region          domain block -0.004 0.004 -0.004 0.004 -0.016 0.016 units box
+
+# create the simulation domain and 1 material types (with friction/frictionless)
+create_box      1 domain
+
+# specify the skin distance for neighbor list generation
+neighbor        0.000075 bin
+neigh_modify    delay 0
+
+
+# define the material properties required for granular pair styles
+# type 1 = particles with friction
+fix m1 all property/global youngsModulus peratomtype 1e6 
+fix m2 all property/global poissonsRatio peratomtype 0.42 
+fix m3 all property/global coefficientRestitution peratomtypepair 1 0.9  
+fix m4 all property/global coefficientFriction peratomtypepair 1 0.1 
+
+# specify contact model to use
+pair_style  gran model hertz tangential incremental_history limitForce on
+pair_coeff  * *
+
+# set the time step
+timestep    0.0000025
+
+# apply gravity
+fix gravity all gravity 9.81 vector 0.0 0.0 -1.0
+
+# define walls
+fix xwall1 all wall/gran model hertz tangential incremental_history primitive type 1 xplane -0.004
+fix xwall2 all wall/gran model hertz tangential incremental_history primitive type 1 xplane 0.004
+fix ywall1 all wall/gran model hertz tangential incremental_history primitive type 1 yplane -0.004
+fix ywall2 all wall/gran model hertz tangential incremental_history primitive type 1 yplane 0.004
+fix zwall1 all wall/gran model hertz tangential incremental_history primitive type 1 zplane 0.0000
+
+# particle distributions and insertion
+fix pts1 all particletemplate/sphere 367127 atom_type 1 volume_limit 1e-14 density constant 1500 radius constant 3.75e-5
+fix pdd1 all particledistribution/discrete 681573 1 pts1 1.0
+
+# inserting particles as a pack with mass loading of 0.05
+fix ins1 all insert/pack seed 4763687 distributiontemplate pdd1 vel constant 0.0 0.0 0.0 &
+    insert_every once overlapcheck yes all_in yes volumefraction_region 0.05 region domain
+
+# use constant NVE integration to update position, velocity and angular velocity
+fix integr all nve/sphere
+
+# output settings, include kinetic energy
+thermo_style    custom step atoms ke
+
+# set frequency of output
+thermo          1000
+
+# ignore particles leaving the simulation domain,
+# do not normalize thermodynamic output values by the number of atoms
+thermo_modify   lost ignore norm no
+compute_modify  thermo_temp dynamic yes
+
+# insert the first particles so that dump is not empty
+run 1
+
+# output particle properties
+dump dmp all custom/vtk 1000 post/liggghts_init_*.vtk id type x y z vx vy vz &
+     fx fy fz omegax omegay omegaz radius
+
+# run up to 1000 time steps
+run 1000 upto
+
+# write the restart file
+write_restart   post/restart/liggghts.restart
+

tutorials/cfdemSolverPimple/PeriodicBox/DEM/in.liggghts_run

@@ -0,0 +1,92 @@
+################################################################################
+# brief: Periodic box - run                       				#
+#                                                                              #
+# Periodic box simulations of Geldart A particles (d=0.075mm, rho=1500kg/m3)   #
+# Cf. Radl, S. and Sundaresan, S., A drag model for filtered Euler–Lagrange 	#
+#     simulations of clustered gas–particle suspensions. 			#
+#     Chemical engineering science, (2014).  					#
+# mass loading = 0.05                                                          #
+# authors: Behrad Esgandari                                                    #
+# date: Aug 2023                                                               #
+# copyright: 2023- JKU Linz                                                    #
+################################################################################
+
+log             ../DEM/log.liggghts
+thermo_log      ../DEM/post/thermo.txt
+
+# define the attributes associated with the particles,
+# 'granular' (or 'sphere') style uses diameter, mass and angular velocity
+atom_style      granular
+
+# use an array to map particle IDs to local storage index,
+atom_modify     map array
+
+# set simulation domain to be periodic in x y z
+boundary        p p p
+
+# save communication by turning off Newton's 3rd law for pairwise interaction,
+# note: this setting only influences communication between procs, Newton's
+# 3rd law is still used for contact force calculations
+newton          off
+
+# use a single value for ghost particle cutoff distance and
+# enable velocity to be communicated with ghost particles
+communicate     single vel yes
+
+# set unit system to SI
+units           si
+
+# specify domain decomposition for parallel execution
+processors      4 2 4
+
+# read the restart file
+read_restart    ../DEM/post/restart/liggghts.restart
+
+# specify the skin distance for neighbor list generation
+neighbor        0.000075 bin
+neigh_modify every 5 delay 0 check no
+
+# define the material properties required for granular pair styles
+# type 1 = particles with friction
+fix m1 all property/global youngsModulus peratomtype 1e6 
+fix m2 all property/global poissonsRatio peratomtype 0.42 
+fix m3 all property/global coefficientRestitution peratomtypepair 1 0.9  
+fix m4 all property/global coefficientFriction peratomtypepair 1 0.1 
+
+# specify contact model to use
+pair_style  gran model hertz tangential incremental_history limitForce on
+pair_coeff  * *
+
+# set the time step
+timestep    0.000001
+
+# apply gravity
+fix gravity all gravity 9.81 vector 0.0 0.0 -1.0
+
+# set up coupling to CFD simulation
+fix cfd  all couple/cfd couple_every 50 mpi
+fix cfd2 all couple/cfd/force/implicit
+
+# use constant NVE integration to update position, velocity and angular velocity
+fix         integr all nve/sphere
+
+# output settings, include kinetic energy
+thermo_style    custom step atoms ke
+
+# set frequency of output
+thermo          1000
+
+# ignore particles leaving the simulation domain,
+# do not normalize thermodynamic output values by the number of atoms
+thermo_modify   lost ignore norm no
+compute_modify  thermo_temp dynamic yes
+
+# output particle properties (same frequency as CFD output)
+dump dmp all custom/vtk 10000 ../DEM/post/liggghts_run_*.vtk id type x y z vx vy vz &
+     fx fy fz omegax omegay omegaz radius
+     
+dump dmp2 all custom 10000 ../DEM/post/liggghts_run_*.run id type x y z vx vy vz &
+     fx fy fz omegax omegay omegaz radius
+
+# run 1 time step to initialize all DEM systems
+run 1

tutorials/cfdemSolverPimple/PeriodicBox/parCFDDEMrun.sh

@@ -0,0 +1,44 @@
+#!/bin/bash
+#------------------------------------------------------------------------------
+# parCFDDEMrun script for periodic box test case
+# run periodic box CFD-DEM
+# Behrad Esgandari - August 2023
+#------------------------------------------------------------------------------
+
+#- source CFDEM env vars
+. ~/.bashrc
+
+#- include functions
+source $CFDEM_PROJECT_DIR/etc/functions.sh
+
+#------------------------------------------------------------------------------
+#- define variables
+casePath="$(dirname "$(readlink -f ${BASH_SOURCE[0]})")"
+logpath=$casePath
+headerText="run_periodic_box"
+logfileName="log_$headerText"
+solverName="cfdemSolverPimple"
+nrProcs="32"
+machineFileName="none"   # yourMachinefileName | none
+debugMode="off"          # on | off| strict
+runCleanUp="false"
+#------------------------------------------------------------------------------
+
+#- call function to run a parallel CFD-DEM case
+parCFDDEMrun $logpath $logfileName $casePath $headerText $solverName $nrProcs $machineFileName $debugMode
+
+if [ $runCleanUp == "true" ]
+    then
+        #- clean up case
+        echo "deleting data at: $casePath :\n"
+        source $WM_PROJECT_DIR/bin/tools/CleanFunctions
+        cd $casePath/CFD
+        cleanCase
+        rm $casePath/DEM/post/*.*
+        touch $casePath/DEM/post/.gitignore
+        rm $casePath/DEM/post/restart/*.*
+        touch $casePath/DEM/post/restart/.gitignore
+fi
+
+echo "done"
+

tutorials/cfdemSolverPimple/PeriodicBox/parDEMrun.sh

@@ -0,0 +1,30 @@
+#!/bin/bash
+
+#===================================================================#
+# DEM run script for periodic box testcase
+# init periodic box
+# Behrad Esgandari - August 2023
+#===================================================================#
+
+#- source CFDEM env vars
+. ~/.bashrc
+
+#- include functions
+source $CFDEM_PROJECT_DIR/etc/functions.sh
+
+echo "starting DEM run in parallel..."
+#--------------------------------------------------------------------------------#
+#- define variables
+casePath="$(dirname "$(readlink -f ${BASH_SOURCE[0]})")"
+logpath="$casePath"
+headerText="run_liggghts_init_DEM"
+logfileName="log_$headerText"
+solverName="in.liggghts_init"
+nrProcs=32
+machineFileName="none"
+debugMode="off"
+#--------------------------------------------------------------------------------#
+
+#- call function to run DEM case
+parDEMrun $logpath $logfileName $casePath $headerText $solverName $nrProcs $machineFileName $debugMode
+

tutorials/cfdemSolverPimple/PeriodicBox/prerun.sh

@@ -0,0 +1,13 @@
+#!/bin/bash
+
+#- define variables
+casePath="$(dirname "$(readlink -f ${BASH_SOURCE[0]})")"
+
+# check if mesh was built
+if [ -f "$casePath/CFD/constant/polyMesh/boundary" ]; then
+    echo "mesh was built before - using old mesh"
+else
+    echo "mesh needs to be built"
+    cd $casePath/CFD
+    blockMesh
+fi