A multi-layered wall with the dimensions shown in the figure has temperatures of 200°C and 50°C over the left and right surfaces, respectively. If the thermal conductivities of the wall materials A and C are k-60 W/m-K, k 24 W/m-K. If total rate of heat transfer through the wall is 175 W, what is the thermal conductivity of material B? T- 200°C soc 6 cm 2 cm 25 om 4 cm

A multi-layered wall with the dimensions shown in the figure has temperatures of 200°C and 50°C over the left and right surfaces, respectively. If the thermal conductivities of the wall materials A and C are k-60 W/m-K, k 24 W/m-K. If total rate of heat transfer through the wall is 175 W, what is the thermal conductivity of material B? T- 200°C soc 6 cm 2 cm 25 om 4 cm

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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.34P: A section of a composite wall with the dimensions shown below has uniform temperatures of 200C and...

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1.10 A heat flux meter at the outer (cold) wall of a concrete building indicates that the heat loss through a wall of 10-cm thickness is . If a thermocouple at the inner surface of the wall indicates a temperature of 22°C while another at the outer surface shows 6°C, calculate the thermal conductivity of the concrete and compare your result with the value in Appendix 2, Table 11.
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1.1 On a cold winter day, the outer surface of a 0.2-m-thick concrete wall of a warehouse is exposed to temperature of –5°C, while the inner surface is kept at 20°C. The thermal conductivity of the concrete is 1.2 W/m K. Determine the heat loss through the wall, which is 10-m long and 3-m high. Problem 1.1
One end of a 0.3-m-long steel rod is connected to a wall at 204C. The other end is connected to a wall that is maintained at 93C. Air is blown across the rod so that a heat transfer coefficient of 17W/m2 K is maintained over the entire surface. If the diameter of the rod is 5 cm and the temperature of the air is 38C, what is the net rate of heat loss to the air?
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