2. Water flows through a thick-walled tube with an inner diameter of 12 mm and a length of 8 m. Thetube is immersed in a well-stirred, hot reaction tank that maintains the outer surface of the tube at85 °C. The conduction resistance of the tube wall (based on the inner surface area) is R = 0.002 m²-K/W. The inlet temperature of the water is Tmi = 20 °C, and the flow rate is 33 kg/h. Hint: seeEquation 8.45b. a. Estimate the outlet temperature of the water, Tmo. Assume, and then justify, fully developed flow and thermal conditions within the tube. b. Do you expect Tmo to increase or decrease if combined thermal and hydrodynamic entry conditions exist within the tube? Estimate the outlet temperature of the water for this condition.

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