Water at the rate of 4.0 kg/s is heated from 40.0 to 60.0 °C in a shell-and-tube heat exchanger. On the shell side one pass is used with water as the heating fluid, 2.0 kg/s, entering the exchanger at 94.0 °C. The overall heat-transfer coefficient is 1420 W/m².°C, and the average water velocity in the 2.0-cm diameter tubes is 0.4 m/s. a) Calculate the heat transfer area Aş using LMTD method and &-NTU method, compare and comment on the two results. b) Because of space limitations, the tube length must not be longer than 3.0 m. Calculate the number of tube passes, the number of tubes per pass, and the length of the tubes, consistent with this restriction.

Water at the rate of 4.0 kg/s is heated from 40.0 to 60.0 °C in a shell-and-tube heat exchanger. On the shell side one pass is used with water as the heating fluid, 2.0 kg/s, entering the exchanger at 94.0 °C. The overall heat-transfer coefficient is 1420 W/m².°C, and the average water velocity in the 2.0-cm diameter tubes is 0.4 m/s. a) Calculate the heat transfer area Aş using LMTD method and &-NTU method, compare and comment on the two results. b) Because of space limitations, the tube length must not be longer than 3.0 m. Calculate the number of tube passes, the number of tubes per pass, and the length of the tubes, consistent with this restriction.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.54P

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