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ashghan June 11, 2014 09:50
filling a tank with water
 
1 Attachment(s)
Hello,

I am trying to fill a tank with water as shown in the figure. The red line indicates the water inlet at t=0 and the green line indicates the air exit. The picture was taken at 46 secs with the timestep being 0.0001. I have been running the case for over two weeks and the water level stopped to be filled in as in the screenshot. I am using the following initial conditions.

alpha.water
Code:
dimensions      [0 0 0 0 0 0 0];

internalField  uniform 0;

boundaryField
{
    inlet
    {
        type            inletOutlet;
        inletValue      uniform 1;
        value          uniform 1;
    }
    outlet
    {
        type            zeroGradient;
    }
    walls
    {
        type            zeroGradient;
    }
}
p_rgh
Code:
dimensions      [1 -1 -2 0 0 0 0];

internalField  uniform 0;

boundaryField
{
    inlet
    {
        type            fixedFluxPressure;
        value          uniform 0;
    }

    outlet
    {
        type            outletInlet;
        outletValue        uniform 0;
            value                uniform 0;
    }

    walls
    {
        type            totalPressure;
        p0              uniform 0;
        U              U;
        phi            phi;
        rho            rho;
        psi            none;
        gamma          1;
        value          uniform 0;
    }

   
}
U
Code:
dimensions      [0 1 -1 0 0 0 0];

internalField  uniform (0 0 0);

boundaryField
{
    inlet
    {
        type          fixedValue;
        value          uniform (2 0 0);
    }

    outlet
    {
        type            pressureInletOutletVelocity;
        value          uniform (0 0 0);
    }

    walls
    {
        type            fixedValue;
        value          uniform (0 0 0);
    }

   
}
Can somebody indicate me where I am going wrong or tell me how to speed up the calculation.

Regards
Ashwin

wouter June 11, 2014 18:11
2 Attachment(s)
hello ashghan,
The problem is the pressure definition. The number of variables is not equal to the number of freedom. Your system needs a point where the pressure is known.
If you look at the angledDuct turorial and remove the viscosity things (in 0 dir two boundaries, in fvOptions remove all you have a working case. I did this with a simple form of your fueltank? It ran for less than 4 hours.
I enclosed my case, but I had to remove the mesh because of the size restrictions.

Hope this helps
Wouter

ashghan June 18, 2014 08:28
Hey,

Yeah it works. Thanks :)


Quote:
Originally Posted by wouter (Post 496674)
hello ashghan,
The problem is the pressure definition. The number of variables is not equal to the number of freedom. Your system needs a point where the pressure is known.
If you look at the angledDuct turorial and remove the viscosity things (in 0 dir two boundaries, in fvOptions remove all you have a working case. I did this with a simple form of your fueltank? It ran for less than 4 hours.
I enclosed my case, but I had to remove the mesh because of the size restrictions.

Hope this helps
Wouter

me12p1006 August 21, 2017 07:15
Help
 
1 Attachment(s)
Hi,

I am trying to solve water filling bottle tutorial from long back (http://www.tfd.chalmers.se/~hani/kur...Hemida_VOF.pdf). I am not getting reasonable results.

I used inlet velocity as 0.1 m/sec. I am attaching my FOAM files. Please kindly let me know what mistake I am doing.


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