2. Consider steady heat transfer between two large parallel plates at constant temperatures of T1 = 295 K and T2 = 155 K that are L = 2 cm apart. Assuming the surfaces to be black, determine the rate of heat transfer between the plates per unit surface area assuming the gap between the plates is (a) filled with atmospheric air,(k = 0.01979 W/m- o C) (b) evacuated,(c) filled with superinsulation having an apparent thermal conductivity of 0.00015 W/m · °C.

2. Consider steady heat transfer between two large parallel plates at constant temperatures of T1 = 295 K and T2 = 155 K that are L = 2 cm apart. Assuming the surfaces to be black, determine the rate of heat transfer between the plates per unit surface area assuming the gap between the plates is (a) filled with atmospheric air,(k = 0.01979 W/m- o C) (b) evacuated,(c) filled with superinsulation having an apparent thermal conductivity of 0.00015 W/m · °C.

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.

Chapter11: Heat Transfer By Radiation

Section: Chapter Questions

Problem 11.32P

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