Hot air at atmospheric pressure and 85°C enters a 10-m-long uninsulated square duct of cross section 0.12 m x 0.12 m that passes through the attic of a house at a rate of 0.11 m3/s. The duct is observed to be nearly isothermal at 70°C. Determine the exit temperature of the air. (Properties of air ρ= 0.9994 kg/m3, υ = 2.097 x10-5 kg/m.s, k= 0.02953 W/m.K, Pr= 0.7154, Cp: 1008 J/kg.oC)

Hot air at atmospheric pressure and 85°C enters a 10-m-long uninsulated square duct of cross section 0.12 m x 0.12 m that passes through the attic of a house at a rate of 0.11 m3/s. The duct is observed to be nearly isothermal at 70°C. Determine the exit temperature of the air. (Properties of air ρ= 0.9994 kg/m3, υ = 2.097 x10-5 kg/m.s, k= 0.02953 W/m.K, Pr= 0.7154, Cp: 1008 J/kg.oC)

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.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.65P

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