C A fused-quartz sphere has a thermal diffusivity of 9.5 x 10-' m²/s, a diameter of 2.5 cm, and a thermal conductivity of 1.52 W/m · °C. The sphere is initially at a uniform temperature of 25°C and is suddenly subjected to a convection environment at 200°C. The convection heat-transfer coefficient is 110 W/m2 .°C. Calculate the temperatures at the center and at a radius of 6.4 mm after a time of 3 min.

C A fused-quartz sphere has a thermal diffusivity of 9.5 x 10-' m²/s, a diameter of 2.5 cm, and a thermal conductivity of 1.52 W/m · °C. The sphere is initially at a uniform temperature of 25°C and is suddenly subjected to a convection environment at 200°C. The convection heat-transfer coefficient is 110 W/m2 .°C. Calculate the temperatures at the center and at a radius of 6.4 mm after a time of 3 min.

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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