Mercury is to be evaporated at 605?F in a furnace. The mercury flows through a 1-in. BWG No. 18 gauge 304 stainless-steel tube, which is placed in the center of the furnace whose cross section, perpendicular to the tube axis, is a square 8 by 8 in. The furnace is made of brick having an emissivity of 0.85, with the walls maintained uniformly at 1800?F. If the convective heat transfer coefficient on the inside of the tube is 500 Btu/(h ft2 ?F) and the emittance of the outer surface of the tube is 0.60, calculate the rate of heat transfer per foot of tube, neglecting convection within the furnace.GIVENMercury flow through a tube in the center of a furnaceMercury temperature (Tm) = 605?F = 1065 RTube specification: 1 in BWG no 18 gauge stainless steelFurnace cross section is 8 in x 8 in = 0.75 ft x 0.75 ftFurnace emissivity (ε2) = 0.85Furnace wall temperature (T2) = 1800?F = 2260 RTube interior heat transfer coefficient (hci) = 500 Btu/(h ft2 ?F)Tube exterior emissivity (ε1) = 0.60ASSUMPTIONSSteady stateConvection within the furnace isnegligible

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-8 In Fumace Wall, A2 T2 = 2260 R -0.85 8 In Tube, A1 e =0.60