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mateusz.mironiuk
Posts: 2
Registered: ‎05-14-2014

Heat Transfer Simulation through the walls - surface resistance

519 Views, 3 Replies
05-21-2014 05:14 PM

Hi,

 

I'm trying to simulate heat transfer among indoor and outdoor the house.

 

I've set up constant temperature on both sides of the wall as a boundary condition, but my problem is with surface resistance (Rsi, Rse). There's nothing like that in the boundary conditions menu. 

 

Nothing happens when I'm adding the film coefficient on external and internal surfaces (with the value equals of inversed Rsi/Rse value to substitute Rsi/Rse). I guess that it doesn't cooperate when I've set up those BC on the same surface (constant temp. and film coefficient)

 

What should I do to make it work? Should I add an extra layer to the wall or add the air volume with constant temperature instead of wall's surface constant temperature?

 

Thanks in advance for help and sorry for my english :smileywink:

Matthew

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Employee
derrek.cooper
Posts: 65
Registered: ‎04-06-2011

Re: Heat Transfer Simulation through the walls - surface resistance

05-21-2014 05:21 PM in reply to: mateusz.mironiuk
You can add a thermal resistance in the materials section where it adds a thermal resistance. Don?t have the dialog box in front of me at the moment, but select a surface, add materials.. You should see it there?
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New Member
mateusz.mironiuk
Posts: 2
Registered: ‎05-14-2014

Re: Heat Transfer Simulation through the walls - surface resistance

05-21-2014 05:43 PM in reply to: derrek.cooper

I'm looking for the thermal resistance of a layer of material [m^2 * K / W ] which occur between ambiend air and surfaces etc.

 

I actually don't want to change thermal resistance of material (what I've done) but only....well, surface resistance.

 

I clicked right mouse button on particular indoor surface (with "surface" mode) , then chose "Edit...", then "Materials" window showed up. I can choose there "type" among "Solid", "Resistance" and "Contact Resistance" but can't change the walue of contact resistance in materials section.

 

Well, actually contact resistance makes some sense, unit fits as well, but there's only one value available. 3 * 10^-5 m^2 * K / W

I also don't know if it will work when I add constant temperature on the same surface as I add this contact resistance.

 

Although I'm still looking for help, thanks sir :smileywink:

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Valued Contributor
marco.mueller
Posts: 94
Registered: ‎05-16-2012

Re: Heat Transfer Simulation through the walls - surface resistance

05-22-2014 03:54 AM in reply to: mateusz.mironiuk
You should have a look in the help system, at the topic about changing materials, the process would be here the same for you.
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