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problem with total enthalpy solved by rhoporousmrfsimplefoam |
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#1 | |
New Member
Join Date: Oct 2011
Posts: 4
Rep Power: 15 ![]() |
Hi all!
I'm solving a compressor with rhoporousmrfsimplefoam and my problem is,that my real total enthalpy is below the isentrope one at the outlet. So i have an efficieny factor above 1(what a nice factor ![]() These are the files of the pipe-case: Quote:
Regards, Eric |
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#2 |
New Member
Join Date: Oct 2011
Posts: 4
Rep Power: 15 ![]() |
edit: In the case with the simple pipe the total temperature at the outlet is lower than the total temperature at the inlet, but it should be the same, because its adiabatic. I think my BC's are correct, aren't they? So is there a problem with the h-equation or something else?
Thank you in advance! Regards, Eric |
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#3 |
New Member
Martin
Join Date: Feb 2012
Location: Germany
Posts: 13
Rep Power: 0 ![]() |
I encountered a similar issue. I was simulating a compressor wheel with rhoPorousMRFSimpleFoam using OpenFOAM 2.1.x. Despite compression, the temperature decreased by about 30K. Previous simulations with openFOAM 2.0.x resulted in an increase of about 30K.
So I took a closer look at the hEqn.H of the solver: OpenFOAM 2.1.x Code:
fvScalarMatrix hEqn ( fvm::div(phi, h) - fvm::Sp(fvc::div(phi), h) - fvm::laplacian(turbulence->alphaEff(), h) == - fvc::div(phi, 0.5*magSqr(U), "div(phi,K)") ); Code:
fvScalarMatrix hEqn ( fvm::div(phi, h) - fvm::Sp(fvc::div(phi), h) - fvm::laplacian(turbulence->alphaEff(), h) == fvc::div(phi/fvc::interpolate(rho), rho/psi, "div(U,p)") - (rho/psi)*fvc::div(phi/fvc::interpolate(rho)) ); |
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#4 |
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prasant
Join Date: Jan 2013
Posts: 33
Rep Power: 14 ![]() |
Hello All,
Did you get any information regarding correction in hEqn If so, please share the information with me. I tried to modified the hEqn as per Eric comments. But still outlet temperature is decreasing. Regards Prasant. |
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