section. There are no fins attached to the tubes. Cold water enters the tubes at 20°C with an average velocity%3Dof 0.2 m/s, while hot air enters the channel at 140°C at an average velocity of 12 m/s.The longitudinal and transverse pitch of the rod bundles is 0.15 m each. Evaluate the fluid properties at their inlet temperatures and assume surface temperature of the tubes as 100°C. Determine (a) the overall heat transfer coefficient of the heat exchanger (b) the rate of heat transfer using E-NTU method, ( (c) and the outlet temperatures of both fluids. (d) Explain assumptions made during the solution. Also, propose at least three solutions in order to increase the heat transfer through the heat exchanger. State your reasons clearly. (10 Points)
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