A closed room containing hot air is used to cool down slabs of a solid with a conductivity of 160 W/m*K, density of 2950 kg/m3 ), and a heat capacity of 920 J/kg*K). Each solid slab is 2 cm thick. Air circulates withing the room at 15 °C with a convection heat transfer coefficient of 200 W/m2*K. Do not assume steady heat transfer. (a) What is the final temperature of slabs upon leaving the room, if the temperature of slabs before entering the room is 70 °C. (b) How much more time is needed for the temperature of the solid slabs to decrease by an additional 20 °C

A closed room containing hot air is used to cool down slabs of a solid with a conductivity of 160 W/mK, density of 2950 kg/m3 ), and a heat capacity of 920 J/kgK). Each solid slab is 2 cm thick. Air circulates withing the room at 15 °C with a convection heat transfer coefficient of 200 W/m2*K. Do not assume steady heat transfer. (a) What is the final temperature of slabs upon leaving the room, if the temperature of slabs before entering the room is 70 °C. (b) How much more time is needed for the temperature of the solid slabs to decrease by an additional 20 °C

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 5.36P

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