Stainless steel ball bearings (p=8085 kg/m², k=15.1 W/m°C, and C=0.480 kJ/kg.°C) having diameter of 1.2 cm are to be quenched in water. The ball leaving the oven at a uniform temperature of 900°C and is exposed to air at 30°C and with a convection coefficient of 125W/m².°C. Determine the time necessary to reach its surface to 850°C.

Stainless steel ball bearings (p=8085 kg/m², k=15.1 W/m°C, and C=0.480 kJ/kg.°C) having diameter of 1.2 cm are to be quenched in water. The ball leaving the oven at a uniform temperature of 900°C and is exposed to air at 30°C and with a convection coefficient of 125W/m².°C. Determine the time necessary to reach its surface to 850°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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