Composite walls with no heat generation may also be characterized by series-parallelconfigurations, as shown in the following figure. Although the heat flow is nowmultidimensional, it is often reasonable to assume one-dimensional conditions. Subject to thisassumption, two different thermal circuits may be used. For case (a), it is presumed thatsurfaces normal to the x-direction are isothermal, while for case (b), it is assumed that surfacesparallel to the x-direction are adiabatic. Different results are obtained for the total thermalresistance for conduction. Here important geometrical information and thermal conductivityinformation are as follows.Length: LE-LF-LG=LH=L=1 mArea perpendicular to x-axis: A for sections E and H, 4/2 for sections F and G where A=1 m²Thermal conductivity: ke-ke-ku-k and ke-a-k where k-50 W/(mK) and a-10.1-1) What is the total thermal resistance between T₁ and T2 for case (a), Rtota. The answershould be given in the unit of K/W.1-2)What is the total thermal resistance between Ti and 72 for case (b), Rtot,b. The answershould be given in the unit of K/W.1-3)If a is infinitely large, what is the ratio between the total thermal resistances for cases(a) and (b), Rtot,a/Rtot,b?1455-4 = 46°Area, AT₁-Lake42OTI LECA/25wwGFL(2)kg (4/2)(a)k(A/2)4(1/2)H44444k(A/2)44(472)/2

Let us denote LKA by the symbol R R = LkA= 150=0.02

1-1) What is the total thermal resistance between T₁ and 72 for case (a), Ruota. The answer should be given in the unit of K/W. 1-2) What is the total thermal resistance between Ti and 72 for case (b), Rtot,b. The answer should be given in the unit of K/W.

1-1) What is the total thermal resistance between T₁ and 72 for case (a), Ruota. The answer should be given in the unit of K/W. 1-2) What is the total thermal resistance between Ti and 72 for case (b), Rtot,b. The answer should be given in the unit of K/W.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.37P

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A section of a composite wall with the dimensions shown below has uniform temperatures of 200C and 50C over the left and right surfaces, respectively. If the thermal conductivities of the wall materials are: kA=70W/mK,kB=60W/mK, kC=40W/mK, and kP=20W/mK, determine the rate of heat transfer through this section of the wall and the temperatures at the interfaces. Repeat Problem 1.34, including a contact resistance of 0.1 K/W at each of the interfaces.
A section of a composite wall with the dimensions shown below has uniform temperatures of 200C and 50C over the left and right surfaces, respectively. If the thermal conductivities of the wall materials are: kA=70W/mK,kB=60W/mK, kC=40W/mK, and kD=20W/mK, determine the rate of heat transfer through this section of the wall and the temperatures at the interfaces.
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