Water enters a double pipe heat-exchanger at 60?C. The water flows on the inside through a copper tube 2.54 cm (1 in) ID at a velocity of 2 cm/s. Steam flows in the annulus and condenses on the outside of the copper tube at a temperature of 80?C. Calculate the outlet temperature of the water if the heat exchanger is 3m long.GIVENWater flow through a tube in a double pipe heat-exchangerWater entrance temperature (Tb,in) = 60?CInside tube diameter (D) = 2.54 cm = 0.0254 mWater velocity (V) = 2 cm/s = 0.02 m/sSteam condenses at (Ts) = 0.80?C on the outside of the pipeLength of heat exchanger (L) = 3 mASSUMPTIONSSteady stateThermal resistance of the copper pipe is negligiblePressure in the annulus is uniform therefore, Ts is uniformHeat transfer coefficient of the condensing steam is large (see Table 1.4) so its thermal resistance can be neglectedOutside surface of the heat exchanger isinsulated

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Steam T- 80°C Water Tan = 80°C Copper Pipe ID =2.54 cm L-3m