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Problem with phase change - Relating to TEMPERATURE

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Old   August 5, 2019, 01:12
Default Problem with phase change - Relating to TEMPERATURE
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Kumaresh
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Hello Foamers, In my phase change problem, I want to set the liquid evaporation equal to interfacial temperature (saturation temperature).
My conditions at the interface (boiling plane) are as follows:
Quote:
T= 100 (saturation temperature when phase change occurs)
@T=100 --> [w(moisture content)->at high (-) temperature side =0]

Based on it, mass and heat balances are calculated at interface as,
Mass balance (r) = rho * alpha * (dx/dt) [kg/m2.s] (calculated at -> low (+) temperature side)
Heat balance (-K dT/dx) = (r) * latent heat [W/m2]
TEqn.H
Quote:
forAll(mesh.cells(), celli) {
if (alpha[celli] <= scalar(0.1)) //10% of moisture
{
T[celli] = 373.0; //Tsat = 100deg - T[celli] = Tsat.value();
alpha[celli]= scalar(0); //Moisture content = 0
}
}
volScalarField VX = V.component(vector::X);
// Compute mass source field (mass balance) (rho*alpha1*interface_VELOCITY)
volScalarField mDot = -(rho*alpha*VX);
// Compute energy source field using enthalpy of evaporation (energy balance)
//hDot = -evapEnthalpy*mDot;
{ fvScalarMatrix TEqn
(
fvm::ddt(rho*cp, T) // fvm::ddt(cp, T)
- mDot * cp * gradTx
- fvm::laplacian(K, T) // - fvm::laplacian(lambda/rho, T)
);
TEqn.relax();
TEqn.solve();
}
Hereby, attaching the solver. and attached figure gives the equations and explanations about boiling and convection.
ENERGY EQU: rho*Cp*(delT/delt) = del/delx[K*delT/delx ] + r*cp*delT/delx + rho*delQ/delT (W/m3)
REF - Clear details here in this MANUSCRIPT ~ http://sci-hub.tw/https://doi.org/10...361(83)90225-9 I

I have partially set the condition of boiling in the solver, However, compilation is success - but there found no changes in results of alpha and temperature.
Some assistance will be highly helpful. Thank you
Attached Images
File Type: jpg ATTACHMENT_1_Boiling.jpg (110.9 KB, 13 views)
File Type: png ATTACHMENT_2_Convection.png (153.7 KB, 10 views)
Attached Files
File Type: gz myboilingFoam_solver.tar.gz (112.8 KB, 8 views)
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