A 25-cm-diameter stainless steel ball (p = 8055 kg/m³, Cp =480 J/kg °C) is removed from the oven at a uniform temperature of 300°C (Fig.). The ball is then subjected to the flow of air at 1 atm pressure and 25°C with a velocity of 3 m/s. The surface temperature of the ball eventually drops to 200°C. Determine the average convection heat transfer coefficient during this cooling process and estimate how long the process will take. T₁=25°C V = 3 m/s Air Steel ball 300°C

A 25-cm-diameter stainless steel ball (p = 8055 kg/m³, Cp =480 J/kg °C) is removed from the oven at a uniform temperature of 300°C (Fig.). The ball is then subjected to the flow of air at 1 atm pressure and 25°C with a velocity of 3 m/s. The surface temperature of the ball eventually drops to 200°C. Determine the average convection heat transfer coefficient during this cooling process and estimate how long the process will take. T₁=25°C V = 3 m/s Air Steel ball 300°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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.22P

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