Two thermal reservoirs are connected by a solid copper bar. The bar is 2 m long, and the temperatures of the reservoirs are 80.0∘C and 20.0∘C. a) Suppose that the bar has a constant rectangular cross section, 10 cm on a side. What is the rate of heat flow through the bar? b) Suppose the bar has a rectangular cross section that gradually widens from the colder reservoir to the warmer reservoir. The area A is determined by A=(0.01m^2)[1.0+x/2.0m] , where x is the distance along the bar from the colder reservoir to the warmer one. Find the rate of heat flow and the rate of change of temperature with distance at the colder end, at the warmer end, and at the middle of the bar.

Two thermal reservoirs are connected by a solid copper bar. The bar is 2 m long, and the temperatures of the reservoirs are 80.0∘C and 20.0∘C. a) Suppose that the bar has a constant rectangular cross section, 10 cm on a side. What is the rate of heat flow through the bar? b) Suppose the bar has a rectangular cross section that gradually widens from the colder reservoir to the warmer reservoir. The area A is determined by A=(0.01m^2)[1.0+x/2.0m] , where x is the distance along the bar from the colder reservoir to the warmer one. Find the rate of heat flow and the rate of change of temperature with distance at the colder end, at the warmer end, and at the middle of the bar.

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 2.21P

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