Hot air at atmospheric pressure and 80°C enters an 8-m-long uninsulated square duct of cross- section 0.2-mx0.2-m that passes through the attic of a house at a rate of 0.15 m³/s (see figure). The duct is observed to be nearly isothermal at 60° C. Determine the convection heat transfer coefficient (in W/m²-K) inside the duct. For air at 80°C:

Hot air at atmospheric pressure and 80°C enters an 8-m-long uninsulated square duct of cross- section 0.2-mx0.2-m that passes through the attic of a house at a rate of 0.15 m³/s (see figure). The duct is observed to be nearly isothermal at 60° C. Determine the convection heat transfer coefficient (in W/m²-K) inside the duct. For air at 80°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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.32P

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