[cfdsolver1]

My Problem:





My question:

Hello everyone. I am working on convective heat transfer problem. I want to solve temperature both for fluid and solid regions. As I know, I can model this using multiRegionSolver of OpenFOAM. I want to generate heat inside solid block and analyze effect of solid thermal conductivity on heat transfer.

I think I can do this by adding source term to energy equation for solid region. I am beginner at OpenFOAM and I could not find a way to add heat generation as a source term into my solid region energy equation. Is it possible to do this with using OpenFOAM default solvers or do I need to write my own solver?

Thank you very much.

[Bloerb]

This is implemented inside the fvOptions. You can simply add that to your chtmultiregion calculation without modifying the solver.

[Aaron_L]

Hi,cfdsolver1

just use swak4foam to add source term, the source term expression like this

expressions
(
Q1
{
field Q;
expression "exp(pos().x)";
condition "(mag(pos().x)<=1) && (mag(pos().y)<=1)";
}

);

the pos().x represent the position of x coordinate

I also do a research in mixed convection using openfoam and fluent, I use openfoam for one year and new to fluent, maybe we can communicate with each other.

best wishes,
Aaron

[cfdsolver1]

Originally Posted by Bloerb

This is implemented inside the fvOptions. You can simply add that to your chtmultiregion calculation without modifying the solver.

Bloerb, thank you very much for your help. Do you have any example or tutorial about using fvOptions for heat transfer problems? Actually, I have come up with fvOptions suggestion before posting my problem here but most implementations were related to momentum equation. I did not understand well how I can include fvOptions into energy equation so any help appreciated.

Originally Posted by Aaron_L

Hi,cfdsolver1

just use swak4foam to add source term, the source term expression like this

the pos().x represent the position of x coordinate

I also do a research in mixed convection using openfoam and fluent, I use openfoam for one year and new to fluent, maybe we can communicate with each other.

best wishes,
Aaron

Dear Aaron, thank you for your reply. Is it possible to define source term using swak4foam for a region/surface? Or pos().x will handle it directly for me? I did not know swak4foam and I am confused little bit. I have a solid region and I want to apply heat generation directly to that region without dealing with its coordinates.

Also, Vice versa here, I have 6 years experience in modeling mixed convection using Fluent and I am totally new in OpenFOAM. Any help is really appreciated. You can also find me whenever you need help in Fluent.

[Aaron_L]

hi,cfdsolver1, swak4foam can easily help you deal with nonuniform source term field, As far as I know, use fvOptions can only deal with it uniform field/region/patch.

firstly, you can define a source term field Q

volScalarField Q
(
IOobject
(
"Q",
runTime.timeName(),
mesh,
IOobject::MUST_READ,
IOobject::AUTO_WRITE
),
mesh
);

the add source term Q in TEqn in solid region

fvScalarMatrix TEqn
(
fvm::ddt(rho*cp,T)
- fvm::laplacian(K, T)
- Q
);
TEqn().solve();

then, if you are uniform field,you need to define Q interalField and boundaryField like this

dimensions [ 1 -1 -3 0 0 0 0 ];

internalField uniform 0;

boundaryField
{
yourpatch
{
type fixedValue;
value uniform 0;
}
}

if you are nonuniform field, you can use swak4foam.

[akidess]

Originally Posted by Aaron_L

As far as I know, use fvOptions can only deal with it uniform field/region/patch.

Pretty sure this is false. The cellZones can be arbitrary.

[Mohammad Jam]

Hi Dear foamers

Do you have any experience in implementing mixed derivative term ddt{d2dx2} in chtMultiRegionFoam solver?

Regards,
Jam

[cfdsolver1]

Thank you for your comment akidess. I have no idea about swak4foam yet, so I think fvOptions might be more easier for me, I guess.

Originally Posted by akidess

Pretty sure this is false. The cellZones can be arbitrary.

Originally Posted by Aaron_L

hi,cfdsolver1, swak4foam can easily help you deal with nonuniform source term field, As far as I know, use fvOptions can only deal with it uniform field/region/patch.

firstly, you can define a source term field Q

the add source term Q in TEqn in solid region

then, if you are uniform field,you need to define Q interalField and boundaryField like this


if you are nonuniform field, you can use swak4foam.

I will definitely check swak4foam too, thank you so much!

[jeanpinto24|]

Dear all, by adding a new source term to the energy equation, which in my case is the energy delivered by people in a classroom. I must suppose that by adding this term to the energy equation, I must regard it as a positive heat that is gained by the fluid. Now I have the question of how to create Q internalFiel and boundaryFiel

[gouravjee]

Hello everyone,
i want to know about how to write expression in openfoam
for the term which i have attached below



dist.png
thanks in advance