At a rate of 5.43 gpm, water at 80?F enters a No. 18 BWG 5/8-in a condenser tube made of nickel chromium steel (k = 15 Btu/(h ft ?F)) . The tube is 10 ft long and its outside is heated by steam condensing at 120?F. Under these conditions, the average heat transfer coefficient on the water side is 1750 Btu/(h ft2 ?F), and the heat transfer coefficient on the steam side may be taken as 2000 Btu/(h ft2 ?F). On the interior of the tube, however, there is a scale having a thermal conductance equivalent to 1000 Btu/(h ft2 ?F).(a) Calculate the overall heat transfer coefficient U per square foot of exterior surface area.(b) Calculate the exit temperature of the water.GIVENA nickel chromium steel condenser tube with water inside and condensing steam outsideWater flow rate v = 5.43 gal/minWater inlet temperature (Tw,in) = 80?FTube: No. 18 BWG 5/8 inSteel thermal conductivity (kst) = 15 Btu/(h ft ?F)Tube length (L) = 10 ftSteam temperature (Ts) = 120?FAverage water- side transfer coefficient (hi) = 1750 Btu/(h ft2 ?F)Average steam transfer coefficient (ho) = 2000 Btu/(h ft2 ?F)Interior scaling conductance (1/Ri) = 1000 Btu/(h ft2?F)

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Condensing Steam T,= 120°F Water Tuh = 80°F v-543 gal/min