[skuznet]

Hello!

I would like to apply fixed heat flux to my solid boundary in a conjugate heat transfer problem. Is there a BC allowing to prescribe heat flux q directly or do I have to use fixedGradient for the temperature grad T=-q/kappa?

Thank you!

[zfaraday]

Hi Sergey,

do you really need another boundary condition than fixedGradient for that? It's the most simple for this purpose, if not the only one...

Regards,

Alex

[skuznet]

It would be just more convenient to prescribe flux directly. If i change, for example, material properties, i would need to change my kappa in BC to keep same flux, which makes more space for mistakes.

[zfaraday]

Maybe it's a bit late or maybe you have already found it, but I think that what you need is externalWallHeatFluxTemperature

Regards,

alex

[Barbara]

I have used this:

type compressible::turbulentHeatFluxTemperature;
heatSource power;
q uniform 15000;
kappa solidThermo;
kappaName none;
value uniform 700;

but it seems it doesn't work because when I check heat fluxes with wallHeatFlux utility the result is the following:

Time = 8100
Selecting thermodynamics package
{
type heSolidThermo;
mixture pureMixture;
transport constIso;
thermo hConst;
equationOfState rhoConst;
specie specie;
energy sensibleEnthalpy;
}


Wall heat fluxes [W]
defaultFaces 0
chapa_to_pedestalinf 0
chapa_to_air 0
chapa_to_pedestalsup 0

I was wondering if anybody has used a succesful wall heat flux boundary condition over a solid or if anybody

[Barbara]

anybody knows what could be the mistake.


Thanks you in advance,

Bárbara

[jherb]

Have you tried with the correct kappaName? Depending on the OpenFOAM version you use this might be kappaEff or alphaEff.

[Barbara]

I am working with OF 2.2.2
Actually I have tested the same boundary condition adding another line:

type compressible::turbulentHeatFluxTemperature;
heatSource power;
q uniform 15000;
alphaEff alphaEff;
kappa solidThermo;
kappaName none;
value uniform 700;

but the result is the same. Also I've tried the externallWallHeatFlux boundary condition and the results are the same.

[zfaraday]

Barbara, take a look at this thread http://www.cfd-online.com/Forums/sho...d.php?t=136031. Maybe it's something related to it. Sorry for the format, I write from my mobile.