[J.H.59]

Hi there

I'm trying to simulate a rigid sphere in an acoustic field in water to calculate the acoustic radiation force on it and then compare the solution with the analytic one.

The simulation geometry is a sphere in a box and on one site a sinus pressure wave is entering the box. On the other sides of the box there should be non-reflecting BC's. The temperature is hold constant at 293.15K with fixedTemperatureConstraint in fvOptions.
The sphere has the radius 1mm and the size of the box is 0.1m.

My BC's are:


p:

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

internalField   uniform 101325;

boundaryField
{
    inlet
    {            
        type                uniformFixedValue;
        uniformValue        sine;
        uniformValueCoeffs
        {
            t0                  0;
            amplitude           constant 100;
            frequency           constant 10000;
            scale               constant 1;
            level               constant 101325;
        }
        value                uniform 101325;

    }

    sphere
    {
        type            zeroGradient;
    }

    ".*"
    {
        type           waveTransmissive;
        value          uniform 101325;
        field          p;
        phi            phi;
        rho            rho;
        psi            thermo:psi;
        gamma          1.01;
        fieldInf       101325;
        lInf           8e-2;
    }
}

U:

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

internalField   uniform (0 0 0);

boundaryField
{
    inlet
    {
        type        pressureInletOutletVelocity;
        value       uniform (0 0 0);

    }

    sphere
    {
        type            noSlip;
    }

    ".*"
    {
        type       waveTransmissive;
        value      uniform (0 0 0);
        field      U;
        phi        phi;
        rho        rho;
        psi        thermo:psi;
        gamma      1.01;
        fieldInf   (0 0 0);
        lInf       8e-2;
    }
}

T:

dimensions      [0 0 0 1 0 0 0];

internalField   uniform 293.15;

boundaryField
{
    ".*"
    {
        type            zeroGradient;
    }

The thermophysicalProperties:

thermoType
{
    type            heRhoThermo;
    mixture         pureMixture;
    transport       const;
    thermo          hConst;
    equationOfState perfectFluid;
    specie          specie;
    energy          sensibleInternalEnergy;
}

mixture
{
    specie
    {
        molWeight   18.015268;
    }
    equationOfState
    {
        R           461.4;//in J * kg^-1 * K^-1
        rho0        996.2896401;
    }
    thermodynamics
    {
        Cp          4189.683866;
        Hf          333550; //J/kg
    }
    transport
    {
        mu          0.001;
        nu          2.87e-3;
        Pr          6.99;
    }
}

So far I'm just able to run a simulation with rhoPimpleFoam. But the force is not even close to the analytic one.
Is there something wrong with my BC's, the termophysicalProperties or something else?


Thanks in advance