Consider a heat exchanger consisting of 12.5 mm outside diameter copper tubes in a staggered arrangement with transverse spacing 25 mm, longitudinal spacing 30 mm, and 9 tubes in the longitudinal direction. Condensing steam at 150?C flows inside the tubes. The heat exchanger is used to heat a stream of air flowing at 5 m/s from 20?C to 32?C. What is the average heat transfer coefficient and pressure drop for the tube bank?GIVENStaggered copper tube bank with condensing steam inside tubes and air flowing over the outsideTube outside diameter (D) = 12.5 mm = 0.0125 mTransverse spacing (ST) = 25 mm = 0.025 mLongitudinal spacing (SL) = 30 mm = 0.03 mNumber of rows of tubes (N) = 9Steam temperature (Ts) = 150?CAir velocity (Us) = 5 m/sAir temperature: Ta,in = 20?C Ta,out = 32?CASSUMPTIONSSteady stateThermal resistance of the condensing steam and the copper tube is negligible. Therefore, the tube surface temperature =Ts

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Alr Sr- 25 mm 0 +, Tan= 20°c +, T. 150°C U,-5 m/s +. D= 12.5 mm