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Too low flow velocity results for a natural convection problem

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Old   January 16, 2020, 12:14
Default Too low flow velocity results for a natural convection problem
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Alex
Join Date: May 2019
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I am simulating a heat exchange problem of natural convection, there is a hot plate on the central part of the right side, the left is set to slip condition and zeroGradient. Air temperature 300K and plate temperature 360K. After 100s of simulation, from paraview I can see that the velocity of the fluid is of the order of 10^-5 which I think is very very low, considering that in the blockMeshDict file I set "convertToMeters 0.01;" .

Where do you think a mistake could be?

I post the relevant bc and some pictures to make you understand better my problem.

Code:
FoamFile
{
    version     2.0;
    format      ascii;
    class       volVectorField;
    object      U;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField   uniform (0 0 0);

boundaryField
{
    sideWallheated
    {
        type            noSlip;
    }

    rightsideWallsNotheated
    {
        type            noSlip;
    }
    leftsideWallsNotheated
    {
        type            slip;
    }

    inlet
    {
        type pressureInletVelocity;
        value uniform (0 0 0);
    }


    outlet
    {
        type            inletOutlet;
        inletValue      uniform (0 0 0);
        value           uniform (0 0 0);
    }



    #includeEtc "caseDicts/setConstraintTypes"
}
Code:
FoamFile
{
    version     2.0;
    format      ascii;
    class       volScalarField;
    object      T;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions      [0 0 0 1 0 0 0];

internalField   uniform 300;

boundaryField
{
    sideWallheated
    {
        type            fixedValue;
        value           uniform 360;
    }
    
    leftsideWallsNotheated
    {
        type            zeroGradient;
    }

    rightsideWallsNotheated
    {
        type            zeroGradient;
    }
    inlet
    {
        type            inletOutlet;
        inletValue      uniform 300;
        value           uniform 300;
    }

    outlet
    { 
        type            inletOutlet;
        inletValue      uniform 300;
        value           uniform 300;
    }

    #includeEtc "caseDicts/setConstraintTypes"
}
Code:
FoamFile
{
    version     2.0;
    format      ascii;
    class       volScalarField;
    object      p_rgh;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField   uniform 0;

boundaryField
{
    sideWallheated
    {
        type            zeroGradient;    
    }

    leftsideWallsNotheated
    {
        type            fixedFluxPressure;       
    }


    rightsideWallsNotheated
    {
        type            zeroGradient;     
    }


    inlet
    {
        type            totalPressure;
        p0              uniform 0;     
    }

    outlet
    {
        type            fixedFluxPressure;        
    }

    #includeEtc "caseDicts/setConstraintTypes"
}
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File Type: png Screenshot from 2020-01-16 18-02-50.png (50.7 KB, 2 views)
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