0.8 kg/s of water enters the tube from a type 2 shell-pass, 4 tube-pass heat exchanger at 17˚C and leaves the tube at 37˚C. This water is used to cool the air entering the shell at a temperature of 250˚C. U=432 W/m2.˚C. Define a. The temperature of the air coming out of the heat exchanger b. The area of the heat exchanger required. c. Heat exchanger effectiveness d. After using the heat exchanger for 5 years, it occurs causing an increase in the thermal resistance value of Rf = 0.0005 m2.˚C/W. Calculate what is the temperature of the air coming out of the heat exchanger now?

0.8 kg/s of water enters the tube from a type 2 shell-pass, 4 tube-pass heat exchanger at 17˚C and leaves the tube at 37˚C. This water is used to cool the air entering the shell at a temperature of 250˚C. U=432 W/m2.˚C. Define a. The temperature of the air coming out of the heat exchanger b. The area of the heat exchanger required. c. Heat exchanger effectiveness d. After using the heat exchanger for 5 years, it occurs causing an increase in the thermal resistance value of Rf = 0.0005 m2.˚C/W. Calculate what is the temperature of the air coming out of the heat exchanger now?

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.

Chapter10: Heat Exchangers

Section: Chapter Questions

Problem 10.13P

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