The outer facing of a room is constructed from 25 cm thick brick, 2.5 cm of mortar, 10 cm of limestone (k = 0.186 W/m-K) and 1.2 cm of plaster (k = 0.096 W/m-K). Thermal conductivities of mortar and brick are both 0.52 W/m-K. Assume that the heat transfer coefficients on the inside (plaster side) and the outside (brick side) surfaces of the wall to be 6 and 12 W/sq. m, respectively. Calculate the rate of heat transfer per 10 sq. m of the wall surface from the room at 18 C to the outside air at 36 C.

The outer facing of a room is constructed from 25 cm thick brick, 2.5 cm of mortar, 10 cm of limestone (k = 0.186 W/m-K) and 1.2 cm of plaster (k = 0.096 W/m-K). Thermal conductivities of mortar and brick are both 0.52 W/m-K. Assume that the heat transfer coefficients on the inside (plaster side) and the outside (brick side) surfaces of the wall to be 6 and 12 W/sq. m, respectively. Calculate the rate of heat transfer per 10 sq. m of the wall surface from the room at 18 C to the outside air at 36 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.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.38P: 2.38 The addition of aluminum fins has been suggested to increase the rate of heat dissipation from...

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