3. Consider a 3 m high rectangular enclosure consisting of two surfaces separated by a 0.1 m air gap at 1 atm. If the surface temperatures across the air gap are 30 °C and -10 °C, determine the ratio of the heat transfer rate for the horizontal orientation (with hotter surface at the bottom) to that for vertical orientation. [1.66] 0.1 m 3 m Air -10 -10°C 30°C

3. Consider a 3 m high rectangular enclosure consisting of two surfaces separated by a 0.1 m air gap at 1 atm. If the surface temperatures across the air gap are 30 °C and -10 °C, determine the ratio of the heat transfer rate for the horizontal orientation (with hotter surface at the bottom) to that for vertical orientation. [1.66] 0.1 m 3 m Air -10 -10°C 30°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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.13P

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