An exterior wall of a house made in three layers (brick (layer 1) + loosely packed...
An exterior wall of a house made in three layers (brick (layer 1) + loosely packed rock (layer 2) + gypsum plaster (layer 3)) may be approximated by a L1=10 cm layer of common brick k1=0.7 W/m℃ and a L3=4 cm layer of gypsum plaster k3=1.07 W/m℃. The total wall surface A=55 m2.
The thickness L2 of loosely packed rock-wool insulation k2=0.65 W/m℃.
The outlet temperature To=45℃, the inner temperature Ti=22℃,
The internal wall temperature T1=27℃ .
The heat transfer coefficients ho=25 W/m2℃ and hi=10 W/m2℃
1.Determine the heat flow rate q .
2.Determine the temperature T4.
3.Determine the thickness for the insulation layer L2.
4.Determine the overall heat transfer coefficient U.
Homework Answers
- At staedy state the heat flow between diffrent points will be equal
- Please let me know if any clarrifications needed
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