[aliahmadi]

hi friends
i am a new user of openfoam and i need to simulate the heat transfer of water in a pipe whit the air out side.
can i use bouyantpimplefoam solver.
or i should use chtmultiregionfoam solver.

i create the geometry with wedge type boundry and toposet rule.


please help me

[nimasam]

You should use bouyantPimpleFoam solver

[nimasam]

You should use chtmultiRegionFoam solver, because in your problem, you have different zones

[aliahmadi]

thanks alot nimasam
but i think that in chtmultiregionfoam solver u should have a solid zone.
am i right???

thanks.

[alexeym]

Hi,

With the description of the problem you've provided, you can use almost any solver from solvers/heatTransfer folder. Do you need evolution of the flow field or steady state? Do you need to account for heat transfer outside the tube (not heat just loss through the pipe boundary but heat transfer in air)? Do you need gravity (if you just need to simulate heat transfer in water in the tube within certain assumptions you can even use pimpleFoam and scalarTransport function object)?

[aliahmadi]

thanks for your response.
yes i need the heat transfer outside the tube .and i can consider the problem steady state or transient..
and
i should say that i have two zones. on for water inside the tube. and other for air outside the tube.

[alexeym]

Then it's chtMultiRegionFoam as nimasam said in his last message, because buoyantPimpleFoam assumes single component medium.

Though, I'm trying to imagine tube, water inside, air outside, properties of the water, heat transfer capabilities of the air. And, well, surely I can imagine a desire to cool a pipe with air flow but it looks a little bit strange.

[aliahmadi]

[QUOTE=alexeym;521437]Then it's chtMultiRegionFoam as nimasam said in his last message, because buoyantPimpleFoam assumes single component medium.

Though, I'm trying to imagine tube, water inside, air outside, properties of the water, heat transfer capabilities of the air. And, well, surely I can imagine a desire to cool a pipe with air flow but it looks a little bit strange.[/QUO


why is strange??

[alexeym]

Well, I'd say it's a simulation for the sake of simulation (or you've omitted certain details). As with your current description you still can assume the air as boundary condition. Or if you're interested in the thermo-flow in air, you can assume water as boundary condition.