The steady-state temperature distribution in a one-dimensional slab of thermal conductivity 50 * w/(mK) and thickness 50 mm is found to be T = a + b * x ^ 2 , where a = 2000C , b=-20000 c/ m^ 2 , T is n^ C and x in meters. (a) What is the heat generation rate in the slab? (b) Determine the heat fluxes at the two wall faces

The steady-state temperature distribution in a one-dimensional slab of thermal conductivity 50 * w/(mK) and thickness 50 mm is found to be T = a + b * x ^ 2 , where a = 2000C , b=-20000 c/ m^ 2 , T is n^ C and x in meters. (a) What is the heat generation rate in the slab? (b) Determine the heat fluxes at the two wall faces

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 1.35P: A section of a composite wall with the dimensions shown below has uniform temperatures of 200C and...

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3.14 A thin-wall cylindrical vessel (1 m in diameter) is filled to a depth of 1.2 m with water at an initial temperature of 15°C. The water is well stirred by a mechanical agitator. Estimate the time required to heat the water to 50°C if the tank is suddenly immersed in oil at 105°C. The overall heat transfer coefficient between the oil and the water is , and the effective heat transfer surface is .
3.10 A spherical shell satellite (3-m-OD, 1.25-cm-thick stainless steel walls) re-enters the atmosphere from outer space. If its original temperature is 38°C, the effective average temperature of the atmosphere is 1093°C, and the effective heat transfer coefficient is , estimate the temperature of the shell after reentry, assuming the time of reentry is 10 min and the interior of the shell is evacuated.
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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.
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