A steel sphere (AISI 1010), 100 mm in diameter, is coated with a dielectric material layer of thickness 1.75 mm and thermalconductivity 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 bathfor which T = 100°C and h = 3000 W/m².K. Estimate the time, in h, 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 (pc)is small compared to that of thesteel sphere.t =h

A steel sphere of material (AISI 1010) Diameter Do =100 mm Dielectric material layer of thickness…

A steel sphere (AISI 1010), 100 mm in diameter, is coated with a dielectric material layer of thickness 1.75 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 larg for which T = 100°C and h = 3000 W/m².K. Estimate the time, in h, required for the coated sphere temperature to reach Hint: Neglect the effect of energy storage in the dielectric material, since its thermal capacitance (pcV)is small compared to steel sphere.

A steel sphere (AISI 1010), 100 mm in diameter, is coated with a dielectric material layer of thickness 1.75 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 larg for which T = 100°C and h = 3000 W/m².K. Estimate the time, in h, required for the coated sphere temperature to reach Hint: Neglect the effect of energy storage in the dielectric material, since its thermal capacitance (pcV)is small compared to 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.

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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