A 1.27-cm diameter copper (r = 8933 kg/m3, C = 385 J/(kg °C)) sphere is heated in a convection furnace for a very long time so that its temperature becomes equal to the temperature of the air in the furnace at 260 °C. Then, the sphere is removed from the furnace and is placed in a forced convection flow where the heat transfer coefficient h is 17 W/(m2 °C) and where the temperature is 38 °C. If the thermal conductivity of copper is 400 W/(m °C) , calculate the Biot number.

A 1.27-cm diameter copper (r = 8933 kg/m3, C = 385 J/(kg °C)) sphere is heated in a convection furnace for a very long time so that its temperature becomes equal to the temperature of the air in the furnace at 260 °C. Then, the sphere is removed from the furnace and is placed in a forced convection flow where the heat transfer coefficient h is 17 W/(m2 °C) and where the temperature is 38 °C. If the thermal conductivity of copper is 400 W/(m °C) , calculate the Biot number.

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 5.54P

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