A metallic ball of radius ro = 5 mm, is initially in equilibrium at 400 C in a furnace. It is suddenly dropped to water at 20 C ( hw = 11003 W/m^2). The properties of the sphere are density= 3000 kg/m3, k = 20 W/m_ K, c = 1000 J/kg K, and α= 6.66E-6 m2/s. Calculate the time required for the center of the sphere to cool to 50 C.

A metallic ball of radius ro = 5 mm, is initially in equilibrium at 400 C in a furnace. It is suddenly dropped to water at 20 C ( hw = 11003 W/m^2). The properties of the sphere are density= 3000 kg/m3, k = 20 W/m_ K, c = 1000 J/kg K, and α= 6.66E-6 m2/s. Calculate the time required for the center of the sphere to cool to 50 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.

Chapter3: Transient Heat Conduction

Section: Chapter Questions

Problem 3.10P: 3.10 A spherical shell satellite (3-m-OD, 1.25-cm-thick stainless steel walls) re-enters the...

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