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Heat flux across the wall, thermal bridge

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Hallo my dear friends!
I am a student of architectural university, I need for a one project to use Heat Transfer und solve this problem.
I think for you, experts, it is not a problem and you can help me easily and with great pleasure ;)
Like finally result I need to know a quantity of heat transfer and to see a one 3D Picture how the heat crosses the wall. For example like this.
I have these dates :
- Text. Temperature of outdoor air -38° C or (235.15 K) Russian cold winter ;)
- Tint. Temperature of indoor air +21° C or (294.15 K)
- ϕint. Relative humidity indoor 55%
- Td. Dewpoint 11,62°C or (284.77 K)
- αext. Heat transfer coefficient of the outer wall surface 23 Watt/ (m2 xC°)
- αint. Heat transfer coefficient of the outer wall surface 8,7 Watt/ (m2 xC°)
- R req. Thermal resistance of external walls 3,62 (m2 x C°/Watt)
For calculation of a quantity of heat transfer, i think i need this Formula:
Q= (Tint.- Text.)* K*F*n*(1+β)

The wall consists of three elements:
1 Brick with density ρ=1300 kg/m3 and thermal conductivity λ=0,4 Watt/mx°C 12cm
2 Thermal Isolation with density ρ=160 kg/m3 and thermal conductivity λ=0,042 Watt/mx°C 15cm
3 Concrete with density ρ=2200 kg/m3 and thermal conductivity λ=1,92 Watt/mx°C 20cm

From what have I start?
I can not find the right field, where I can write my Formula.
I can also leave here my e-mail Adress. mariaiv1980@mail.ru
Please, help me!!!


0 Replies Last Post 11 févr. 2014, 15:49 UTC−5
COMSOL Moderator

Hello maria ivanova

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