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Question 3.297E: Find the rate of conduction heat transfer through a 1.5 cm t...

Find the rate of conduction heat transfer through a 1.5 cm thick hardwood board, k = 0.09 Btu/h-ft-R, with a temperature difference between the two sides of 40 F.

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One dimensional heat transfer by conduction, we do not know the area so we can find the flux (heat transfer per unit area Btu/ft ^{2}h).

 

t =1.5   cm =0.59   in .=0.0492   ft

 

\dot{ q }=\dot{ Q } / A = k \frac{\Delta T }{\Delta x }=0.09 \frac{ Btu }{ h – ft – R } \times \frac{40}{0.0492} \frac{ R }{ ft }=73.2   Btu / ft ^{2}- h

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