Week 11 - Simulation of Flow through a pipe in OpenFoam

theory:

:-

in non ideal fluid dynamics, hagen-poiseullie equation is a physical law that gives pressure drop in an incompressible and newtonian fluid in a laminar flow through a long cylinder pipe of constent cross section

the below blockMeshDict.file is obtained by cpoying and editing the blockmeshdict file from cavity folder by incompressible file it is edited to a wedge angle 4 degree

bloclmeshDict file:-

[0:51 pm, 19/03/2022] Praju: /--------------------------------- C++ -----------------------------------\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Version:  9
     \\/     M anipulation  |
\---------------------------------------------------------------------------/
FoamFile
{
    format      ascii;
    class       dictionary;
    object      blockMeshDict;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

convertToMeters 1;

vertices
(
    (0 0 0 )
    (0 9.996573e-03 -2.617695e-04)
    (0 9.996573e-03 2.617695e-04)
    (2.820000e+00 0 0)
    (2.820000e+00 9.996573e-03 -2.617695e-04 )
    (2.820000e+00 9.996573e-03 2.617695e-04)
);

blocks
(
    hex (0 1 2 0 3 4 5 3) (50 1 200) simpleGrading (2.000000e-01 1 1)
);

edges
(
	arc 1 2 (0 1.000000e-02 0)
	arc 4 5 (2.820000e+00 1.000000e-02 0)
);

boundary
(
    axis
    {
        type empty;
        faces
        (
            (0 3 3 0)
        );
    }
    top
    {
        type wall;
        faces
        (
            (2 5 4 1)
        );
    }
    inlet
    {
        type patch;
        faces
        (
            (0 0 2 1)
        );
    }
     outlet
    {
        type patch;
        faces
        (
            (3 4 5 3)
        );
    }
    wedgeFront
    {
    	type wedge;
    	faces
    	(
    		(0 3 5 2)
    	);
    }
    wedgeBack
    {
    type wedge;
    faces 
    (
    	(0 1 4 3)
    );
    }
);

mergePatchPairs
(
);

// ************************* //

initial and boundray conditions are

pressure:-

/--------------------------------- C++ -----------------------------------\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Version:  9
     \\/     M anipulation  |
\---------------------------------------------------------------------------/
FoamFile
{
    format      ascii;
    class       volScalarField;
    object      p;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField   uniform 0;

boundaryField
{
    axis
    {
        type            empty;
    }

    inlet
    {
        type            zeroGradient;
    }

    outlet
    {
        type            fixedVlaue;
        value		uniform 0.018;
    }
     top
    {
        type            zeroGradient;
    }
     wedgeFront
    {
        type            wedge;
    }
     wedgeBack
    {
        type            wedge;
    }
}

// ************************* //

velocity:-

/--------------------------------- C++ -----------------------------------\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Version:  9
     \\/     M anipulation  |
\---------------------------------------------------------------------------/
FoamFile
{
    format      ascii;
    class       volVectorField;
    object      U;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField   uniform (0.0937312 0 0);

boundaryField
{
    axis 
    {
        type		empty;
    }

    inlet
    {
        type 		fixedvalue;
        value		unifrom (0.0937312 0 0);
    }
   outlet
    {
        type            zeroGradient;
    }
    top
    {
        type 		fixedvalue;
        value		uniform (0 0 0);
    }
    wedgeFront
    {
        type            wedge;
    }
    wedgeBack 
    {
    	type 		wedge;
    }
}

// ************************* //

transport properties:-

/--------------------------------- C++ -----------------------------------\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Version:  9
     \\/     M anipulation  |
\---------------------------------------------------------------------------/
FoamFile
{
    format      ascii;
    class       dictionary;
    location    "constant";
    object      transportProperties;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

nu              [0 2 -1 0 0 0 0] 1e-05;


// ************************* //

after the editing of blockmesh file and run by typeing blockmesh command in terminal window the required blockesh file is created and to check the correctness of the mesh droped in a command called checkMesh in termial window

for postprossesing the blockmesh we used paraFoam command in terminal window. below images showes the results of outputs

figure 1:- mesh created for an angle 4degree

figure2:- velocity magnitude over a mesh

velocity distribution over a mesh in x direction

velocity distribution over a mesh in y-direction

velocity ditributuion over a mesh in z-direction

pressure distribution over a mesh

pressure and velocity magnitude graph:-