A cubical glass furnace, 100cm x 100cm x 100cm is insulated with a refractory brick (k=1.4 W/m·K) of uniform insulation thickness 1cm (See the cross-section below). The inside temperature of the furnace is kept at 1000 °C. The outside air is at 25°C and has a convective heat fer coefficient of 20 W/m ² K. 

(a) Draw a thermal circuit for the furnace 

(b) Find the total thermal resistance 

(c) Find the overall heat transfer coefficient U based on the outer surface of the furnace 

(d) Compute the heat transfer rate.

Transcribed Image Text:

Te-25 "C h20 W/m.K Insulation T-1000 C 1e0 cm 102 cm 192 cm 10ΣΕπ 102 εm Te-25 "C h20 W/m.K Insulation T-1000 C 1e0 cm 102 cm 192 cm 10ΣΕπ 102 εm