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buoyantPimpleFoam General Assumptions (thermophysical model, energy equation, etc) |
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#1 |
New Member
Join Date: Oct 2017
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I am trying to use buoyantPimpleFoam to simulate Rayleigh-Taylor instability of a gas (eventually a reacting simulation). I was looking through the source files and I had some general questions on the assumptions that the solver takes, and hope that someone can shed some light on it for me.
1. The energy equation is states as Code:
fvScalarMatrix EEqn ( fvm::ddt(rho, he) + fvm::div(phi, he) + fvc::ddt(rho, K) + fvc::div(phi, K) + ( he.name() == "e" ? fvc::div ( fvc::absolute(phi/fvc::interpolate(rho), U), p, "div(phiv,p)" ) : -dpdt ) - fvm::laplacian(turbulence->alphaEff(), he) == rho*(U&g) + radiation->Sh(thermo, he) + fvOptions(rho, he) ); ![]() But in the solver energy equation, this is simply states as ![]() 2. The divergence of gradients in OpenFoam (e.g. ![]() ![]() 3. The thermophysical properties for gases seem to me to be overdefined. For example, a sample thermophysical model could be: Code:
thermoType { type heRhoThermo; //Thermophysical Model Based on h/e and rho mixture pureMixture; // Passive Gas Mixtures transport const; // Constant transport properties (mu, Pr, etc.) thermo hConst; // Constant Cp and heat of fusion equationOfState perfectGas; // Ideal Gas Law specie specie; energy sensibleEnthalpy; // Solve Energy Eqn. In Terms of Enthalpy } 4. Why is ![]() Code:
#include "readGravitationalAcceleration.H" #include "readhRef.H" #include "gh.H" Info<< "Reading field p_rgh\n" << endl; volScalarField p_rgh ( IOobject ( "p_rgh", runTime.timeName(), mesh, IOobject::MUST_READ, IOobject::AUTO_WRITE ), mesh ); // Force p_rgh to be consistent with p p_rgh = p - rho*gh; Thank you in advance. |
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#2 |
Senior Member
Jianrui Zeng
Join Date: May 2018
Location: China
Posts: 157
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Hello,I am also confused about these questions above.
Have you found the answer of it? Any idea will be appreciated. |
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Tags |
assumptions, buoyantpimplefoam, consistency, laplacian operator |
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