A double-pipe heat exchanger is used to condense steam at a rate of 120 kg/hr at 45°C. Cooling water (seawater) enters t

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A Double Pipe Heat Exchanger Is Used To Condense Steam At A Rate Of 120 Kg Hr At 45 C Cooling Water Seawater Enters T 1 (83.25 KiB) Viewed 13 times

A double-pipe heat exchanger is used to condense steam at a rate of 120 kg/hr at 45°C. Cooling water (seawater) enters through the inner tube at a rate of 1.2 kg/sec at 15°C. The tube with 25.4 mm outer and 21.44 mm inner diameter is made of steel, k=45W/mK. The heat transfer coefficient the steam side, h, is 7000 W/m²K. For the given problem: a. Draw the diagram of the heat exchanger and label the states of fluid entering and exiting the heat exchanger. b. Calculate the exit temperature of the water, in °C. c. Use an empirical correlation to calculate the convection coefficient (h) inside the tube, in W/m²K. (HINT: The flow is turbulent!) c. Calculate the overall heat transfer coefficient for the clean tube and the length of the heat exchanger. d. The plain tube is replaced by finned tubes. Fins have 100% efficiency and increase the available tube outer surface area by a factor of 2.9. Calculate the new overall heat transfer coefficient and the length.