Concept explainers
A plane wall, 7.5 cm thick, generates heat internally at the rate of 105 W/m3. One side of the wall is insulated, and the other side is exposed to an environment at 90°C. The convection heat transfer coefficient between the wall and the environment is 500 W/m2 K. If the thermal conductivity of the wall is 12 W/m K, calculate the maximum temperature in the wall.
The maximum temperature in the wall
Answer to Problem 2.1P
Maximum temperature in the wall is 128.430C at it occurs at x = 0.
Explanation of Solution
Given Information:
Thickness of the wall L = 7.5 cm = 0.075 m
Rate of internal heat generation qg = 105 W/m3
Temperature of environment = 900C
Convective heat transfer coefficient between the wall and the environment h = 500 W/m2K
Thermal conductivity of the wall k = 12W/mK
Assumptions:
One dimensional steady state heat transfer.
Properties of the wall and convective heat transfer coefficient remains constant.
Explanation: For one dimensional heat transfer with internal heat generation we have:
Conclusion:
Maximum temperature in the wall occurs at x = 0 and it is 128.43 0C .
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Chapter 2 Solutions
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