[FloK]

Hi everyone, i am new to OpenFoam and Linux, and i have a quick question: Is there a way to calculate conductive heat transfer from a fluid to a solid, for example hot water flows through a pipe and cools down by loosing heat to the pipe. I found the chtMultiRegionFoam, but isn`t there an easier way by setting a boundary condition to a special temperature or anything like that? Because i am not interested in the solid part, i just want to know the temperature-field of the fluid... Thanks a lot, Flo

[chandramurthy]

If you are interested in solving fluid zone only, considering heat transfer to the solid walls,
1) chtMultiRegionFoam is not the correct choice
2) try to use simpleFoam or any other incompressible solver (for water) by applying convective heat transfer boundary condition at the fluid boundary(fluid solid interface)
3) to calculated heat transfer coefficient, use any standard empirical correlation from any heat transfer hand book
4) use timevaryingmappedfixedvalue, if your bc changes temporally as well as spatially

[FloK]

Hi,
thanks for the information.
Do you know the name of the Boundary Condition to set HeatFlux through the walls?
Greetings,

FloK

[herbert]

Hi FloK,

you can use the fixedGradient boundary condition. Just divide your heat flux by conductivity.

for example:

wall
{
type fixedGradient;
gradient uniform 1000;
value uniform 300;
}

[Thomas Baumann]

Hi FloK,
you can use the wallheatflux-boundary:
http://openfoamwiki.net/index.php/Contrib_wallHeatFlux

you can implement it by:

wall1
{
type wallHeatFlux;
heatFlux uniform 10000;
}

Regards Thomas

[chandramurthy]

hi fomers,
has anybody tried to apply a convective heat transfer boundary condition with the following constraints,
1) prescribe heat transfer coefficient(h) and free stream temperature (Tinf)
2) h & Tinf are functions of time, space and local wall temperature
3) local wall temperature of previous time step to be an argument for the present time step BC calculation

has anybody did this .....please help.....

thank you

[ronaldo]

could "chtMultiregionFoam" be use to simulate an Heat Exchanger (Solid and fluid region)?

[santoo_cfd]

Originally Posted by chandramurthy

hi fomers,
has anybody tried to apply a convective heat transfer boundary condition with the following constraints,
1) prescribe heat transfer coefficient(h) and free stream temperature (Tinf)
2) h & Tinf are functions of time, space and local wall temperature
3) local wall temperature of previous time step to be an argument for the present time step BC calculation

has anybody did this .....please help.....

thank you

Hi,

Can u be more specific like(any practical application) where do u come across such 3 restrictions for convective boundary condition, espection the 3rd one where previous time step's local temperature to be an argument for present time step BC calculation.

Santosh...

[dorekos]

Hello guys,

I would like to know if I can simulate in openfoam the conduction through solids.
For example the heat through the ground through the floor into a building...

thank you
dorekos