Steel balls (diameter = 21 mm, p = 7833 kg/m, k = 54 W/m:°C, Cp = 0.465 kJ/kg-°C, and a = 1.474x10 m /s) are annealed by heating them first to 870°C in a furnace and then allowing them to cool slowly to 85°C in ambient air at 27°C. What is the total rate of heat transfer from the balls to the ambient air, when 2372 balls are to be annealed per hour (kW)? %3D %3D %3D

Steel balls (diameter = 21 mm, p = 7833 kg/m, k = 54 W/m:°C, Cp = 0.465 kJ/kg-°C, and a = 1.474x10 m /s) are annealed by heating them first to 870°C in a furnace and then allowing them to cool slowly to 85°C in ambient air at 27°C. What is the total rate of heat transfer from the balls to the ambient air, when 2372 balls are to be annealed per hour (kW)? %3D %3D %3D

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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