Hot air at atmospheric pressure and 80°C enters an 8-m-long uninsulated square duet of cross 02 mx 0.2 m that passes through the attic of a house at a rate of 0.15 m/s. The duct is observed to be isothermal at 60°C. Determine Hydraulic diameter and Re. if the flow is Laminar or turbulent mine the length of the entry region and length of fully develop region. Explain how calculate the Nussul er on hot wall experimentally. Air Table :Properties for Air p(kg/m) C₂ (J/kg *C) k (W/m. C) 0.9994 1008 0.02953 Pr 0.7154 v (m²/s) 2.097x10

Hot air at atmospheric pressure and 80°C enters an 8-m-long uninsulated square duet of cross 02 mx 0.2 m that passes through the attic of a house at a rate of 0.15 m/s. The duct is observed to be isothermal at 60°C. Determine Hydraulic diameter and Re. if the flow is Laminar or turbulent mine the length of the entry region and length of fully develop region. Explain how calculate the Nussul er on hot wall experimentally. Air Table :Properties for Air p(kg/m) C₂ (J/kg *C) k (W/m. C) 0.9994 1008 0.02953 Pr 0.7154 v (m²/s) 2.097x10

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 7.34P

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