| J.H.59 |
October 11, 2018 04:41 |
Acoustic radiation force on rigid sphere
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:
Code:
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:
Code:
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:
Code:
dimensions [0 0 0 1 0 0 0];
internalField uniform 293.15;
boundaryField
{
".*"
{
type zeroGradient;
}
The thermophysicalProperties:
Code:
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 |
