9-24 A 0.5-m-long thin vertical copper plate is subjected to a uniform heat flux of 1000 W/m² on one side, while the other side is exposed to air at 5°C. Determine the plate midpoint temperature onosed to air at 5°C. Determine the plate midpoint temperature for (a) a highly polished surface and (b) a black oxidized surface. Hint: The plate midpoint temperature (T,2) has to be found itera- tively. Begin the calculations by using a film temperature of 30°C. Copper plate (highly polishe Copper plate (black oxidized) T surr Air Air 5°C 5°C TL2 (a) (b) We must consider radiation. Use ɛ = 0.02 for polished copper and ɛ = 0.73 for black oxide finish. Ans: a. 147.2°C b. 88.5°C. Show all steps and at least 1 iteration. 1000 W/m² 1000 W/m2

9-24 A 0.5-m-long thin vertical copper plate is subjected to a uniform heat flux of 1000 W/m² on one side, while the other side is exposed to air at 5°C. Determine the plate midpoint temperature onosed to air at 5°C. Determine the plate midpoint temperature for (a) a highly polished surface and (b) a black oxidized surface. Hint: The plate midpoint temperature (T,2) has to be found itera- tively. Begin the calculations by using a film temperature of 30°C. Copper plate (highly polishe Copper plate (black oxidized) T surr Air Air 5°C 5°C TL2 (a) (b) We must consider radiation. Use ɛ = 0.02 for polished copper and ɛ = 0.73 for black oxide finish. Ans: a. 147.2°C b. 88.5°C. Show all steps and at least 1 iteration. 1000 W/m² 1000 W/m2

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 1.48P: A horizontal, 3-mm-thick flat-copper plate, 1-m long and 0.5-m wide, is exposed in air at 27C to...

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A horizontal, 3-mm-thick flat-copper plate, 1-m long and 0.5-m wide, is exposed in air at 27C to radiation from the sun. If the total rate of solar radiation absorbed is 300 W and the combined radiation and convection heat transfer coefficients on the upper and lower surfaces are 20 and 15W/m2K, respectively, determine the equilibrium temperature of the plate.
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