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. The sphere is allowed to remain in the flow for 450 seconds at which time it is returned to the convection furnace. After 900 seconds in the furnace, the temperature of the sphere is 240.5 °C. What is the convective heat transfer coefficient in the convection furnace? 5 O 7.8 W/(m² °C) 15.5 W/(m² °C)

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. The sphere is allowed to remain in the flow for 450 seconds at which time it is returned to the convection furnace. After 900 seconds in the furnace, the temperature of the sphere is 240.5 °C. What is the convective heat transfer coefficient in the convection furnace? 5 O 7.8 W/(m² °C) 15.5 W/(m² °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.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.54P

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