Q) An apple has been put into a freezer at (-18°C) to be cooled. Initially, the apple is at a uniform temperature of 17°C. The convection heat transfer coefficient on its surface is 6 W/m2°C. Assuming the apple as a sphere having a diameter of 10-cm and taking its properties as p = 750 kg/m3, c, = 2850 J/kg-c, and k = 0.450 W/mC, determine; (a) the center temperature of the apple in 45 minutes, (b) the actual amount of heat transfer from the apple, and (c) the final equilibrium temperature of the apple.

Q) An apple has been put into a freezer at (-18°C) to be cooled. Initially, the apple is at a uniform temperature of 17°C. The convection heat transfer coefficient on its surface is 6 W/m2°C. Assuming the apple as a sphere having a diameter of 10-cm and taking its properties as p = 750 kg/m3, c, = 2850 J/kg-c, and k = 0.450 W/mC, determine; (a) the center temperature of the apple in 45 minutes, (b) the actual amount of heat transfer from the apple, and (c) the final equilibrium temperature of the apple.

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.

Chapter4: Numerical Analysis Of Heat Conduction

Section: Chapter Questions

Problem 4.46P

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