January 20, 2025, 19:22
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Low Heat transfer rate in Immersion Quenching Simulation
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#1
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New Member
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Dear all,
I have an assignment, where I try to simulate an immersion quenching process of an aluminium slab. My guidelines were according to Srinivasan et al. paper, Numerical Simulation of immersion quench cooling process: Part I, but recreated in OpenFOAM. I selected the chtMultiRegionTwoPhaseEulerFoam solver, as that seems to closely match the model from the paper.
I modified the solidQuenching2D case, but after comparing to the experimental data, I have incredibly low heat transfer rate to the fluid. For example, in real life the cooling process mostly ended in 0.5 second, but in my calculation the surface barely cooled 3˚C. I tried tinkering with the model and physical properties without luck. (Weirdly, when turning on phaseChange in /constant/phaseProperties, the 14˚C water starts to boil on the surface). I also tried increasing the mesh resolution, but the heat transfer didn't change.
If someone would be kind to review my case, I would be deeply greatful!
Kind regards,
Endre
/constant/phaseProperties:
Code:
/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: v2406 |
| \\ / A nd | Website: www.openfoam.com |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class dictionary;
object phaseProperties;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
type thermalPhaseChangeTwoPhaseSystem;
phases (gas liquid);
// phase change in the bulk of the fluid.
phaseChange on;
//populationBalances (bubbles);
gas
{
type purePhaseModel;
diameterModel isothermal;
isothermalCoeffs
{
d0 5e-3;
p0 1e5;
}
Sc 0.7;
velocityGroupCoeffs
{
populationBalance bubbles;
formFactor 0.5235987756;
sizeGroups
(
f0 {d 0.5e-4; value 0 ;}
f1 {d 1.040e-3; value 0 ;}
f2 {d 1.640e-3; value 0 ;}
f3 {d 2.265e-3; value 0 ;}
f4 {d 2.889e-3; value 0 ;}
f5 {d 3.512e-3; value 0 ;}
f6 {d 4.141e-3; value 0 ;}
f7 {d 4.771e-3; value 1 ;}
f8 {d 5.402e-3; value 0 ;}
f9 {d 6.033e-3; value 0 ;}
f10 {d 6.665e-3; value 0 ;}
f11 {d 7.297e-3; value 0 ;}
f12 {d 7.929e-3; value 0 ;}
f13 {d 8.562e-3; value 0 ;}
f14 {d 9.194e-3; value 0 ;}
f15 {d 1.194e-2; value 0 ;}
f16 {d 2.400e-2; value 0 ;}
f17 {d 2.700e-2; value 0 ;}
f18 {d 3.000e-2; value 0 ;}
);
}
residualAlpha 1e-4;
}
liquid
{
type purePhaseModel;
diameterModel constant;
constantCoeffs
{
d 0.00045;
}
Sc 0.7;
residualAlpha 1e-4;
}
populationBalanceCoeffs
{
bubbles
{
continuousPhase liquid;
coalescenceModels
(
PrinceBlanch
{
C1 0.05;
h0 1e-4;
hf 1e-8;
turbulentCollisions true;
buoyantCollisions false;
laminarShearCollisions false;
}
);
binaryBreakupModels
();
breakupModels
(
LaakkonenAlopaeusAittamaa
{
C1 6;// Default: 6;
C2 0.04;
C3 0.01;
daughterSizeDistributionModel uniformBinary;
}
);
driftModels
(
phaseChange
{
pairNames (gasAndLiquid);
}
densityChange{}
);
nucleationModels
(
wallBoiling
{
velocityGroup gas;
}
);
}
}
blending
{
default
{
type linear;
minFullyContinuousAlpha.gas 0.7;
minPartlyContinuousAlpha.gas 0.3;
minFullyContinuousAlpha.liquid 0.7;
minPartlyContinuousAlpha.liquid 0.3;
}
drag
{
type linear;
minFullyContinuousAlpha.gas 0.7;
minPartlyContinuousAlpha.gas 0.3;
minFullyContinuousAlpha.liquid 0.7;
minPartlyContinuousAlpha.liquid 0.3;
}
heatTransfer
{
type linear;
minPartlyContinuousAlpha.gas 0;
minFullyContinuousAlpha.gas 1;
minPartlyContinuousAlpha.liquid 0;
minFullyContinuousAlpha.liquid 1;
}
massTransfer
{
type linear;
minPartlyContinuousAlpha.gas 0;
minFullyContinuousAlpha.gas 1;
minPartlyContinuousAlpha.liquid 0;
minFullyContinuousAlpha.liquid 1;
}
}
surfaceTension
(
(gas and liquid)
{
type constant;
sigma 0.07;
}
);
saturationModel
{
type function1;
function csvFile;
functionCoeffs
{
nHeaderLine 1;
refColumn 0;
componentColumns (1);
separator ",";
mergeSeparators no;
file "Tsat_water_1_2bar.csv";
outOfBounds clamp;
interpolationScheme linear;
};
};
aspectRatio
(
(gas in liquid)
{
type constant;
E0 1.0;
}
(liquid in gas)
{
type constant;
E0 1.0;
}
);
drag
(
(gas in liquid)
{
type IshiiZuber;
residualRe 1e-4;
swarmCorrection
{
type none;
}
}
(liquid in gas)
{
type IshiiZuber;
residualRe 1e-4;
swarmCorrection
{
type none;
}
}
);
virtualMass
(
(gas in liquid)
{
type constantCoefficient;
Cvm 0.5;
}
(liquid in gas)
{
type constantCoefficient;
Cvm 0.5;
}
);
heatTransfer.gas
(
(gas in liquid)
{
type spherical;
residualAlpha 1e-3;
}
(liquid in gas)
{
type RanzMarshall;
residualAlpha 1e-3;
}
);
heatTransfer.liquid
(
(gas in liquid)
{
type RanzMarshall;
residualAlpha 1e-3;
}
(liquid in gas)
{
type spherical;
residualAlpha 1e-3;
}
);
phaseTransfer
();
lift
(
(gas in liquid)
{
type Tomiyama;
}
);
wallLubrication
(
(gas in liquid)
{
type Antal;
Cw1 -0.01;
Cw2 0.05;
Cwc 10.0;
Cwd 6.8;
p 1.7;
}
);
turbulentDispersion
(
(gas in liquid)
{
type Burns;
sigma 0.7;
Ctd 1.0;
residualAlpha 1e-3;
}
);
// Minimum allowable pressure
pMin 10000;
// ************************************************************************* //
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