A steel sphere (AISI 1010), 100 mm in diameter, is coated with a dielectric material layer of thickness 2 mm and thermal conductivity 0.04 W/m • K. The coated sphere is initially at a uniform temperature of 500°C and is suddenly quenched in a large oil bath for which To = 100°C and h = 3000 W/m • K. Estimate the time required for the coated sphere temperature to reach 150°C. Hint: Neglect the effect of energy storage in the dielectric material, since its thermal capacitance (pcV) is small compared to that of the steel sphere

A steel sphere (AISI 1010), 100 mm in diameter, is coated with a dielectric material layer of thickness 2 mm and thermal conductivity 0.04 W/m • K. The coated sphere is initially at a uniform temperature of 500°C and is suddenly quenched in a large oil bath for which To = 100°C and h = 3000 W/m • K. Estimate the time required for the coated sphere temperature to reach 150°C. Hint: Neglect the effect of energy storage in the dielectric material, since its thermal capacitance (pcV) is small compared to that of the steel sphere

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.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.26P

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