A short brass cyclinder (denisty=8530 kg/m^3, cp=0.389 kJ/kgK, k=110 W/mK, and alpha=3.39*10^-5 m^2/s) of diameter 4 cm and height 20 cm is initially at uniform temperature of 150 degrees C. The cylinder is now placed in atmospheric air at 20 degrees C, where heat transfer takes place by convection with a heat transfer coefficent of 40 W/m^2K. Calculate (a) the center temp of the cylinder, (b) the center temp of the top surface of the cylinder, and (c) the total heat transfer from the cylinder 15 min after the start of the cooling. Solve this problem using the analytical one term approximation method. (Answer: (a) 45.7C, (b)45.3C, (c)87.2 kJ)

A short brass cyclinder (denisty=8530 kg/m^3, cp=0.389 kJ/kgK, k=110 W/mK, and alpha=3.39*10^-5 m^2/s) of diameter 4 cm and height 20 cm is initially at uniform temperature of 150 degrees C. The cylinder is now placed in atmospheric air at 20 degrees C, where heat transfer takes place by convection with a heat transfer coefficent of 40 W/m^2K. Calculate (a) the center temp of the cylinder, (b) the center temp of the top surface of the cylinder, and (c) the total heat transfer from the cylinder 15 min after the start of the cooling. Solve this problem using the analytical one term approximation method. (Answer: (a) 45.7C, (b)45.3C, (c)87.2 kJ)

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.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.31P

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