A heat exchanger wall consists of a copper plate 3/8 in. thick. The heat transfer coefficients on the two sides of the plate are 480 and 1250 Btu/(h ft2 ?F), corresponding to fluid temperatures of 200 and 90?F, respectively. Assuming that the thermal conductivity of the wall is 220 Btu/(h ft ?F),(a) Compute the surface temperatures in ?F, and(b) Calculate the heat flux in Btu/(h ft2).GIVENHeat exchanger wall, thickness (L) = 3/8 in = 0.03125 ftHeat transfer coefficientshc1 = 480 Btu/(h ft2 ?F)hc2 = 1250 Btu/(h ft2 ?F)Fluid temperaturesTf1 = 200?FTf2 = 90?FThermal conductivity of the wall (k) = 220 Btu/(h ft ?F)ASSUMPTIONSOne dimensional heat transfer prevailsThe system has reached steady stateRadiative heat transfer isnegligible

Transcribed Image Text:

Twn. -Tw2 Tr2 = 90°F TH= 200°F