A feed-water heater that supplies a boiler consists of a shell-and-tube heat exchanger with o1 shell pass and two tube passes. One hundred thin-walled tubes each have a diameter of 20 m and a length (per pass) of 2 m. Under normal operating conditions water enters the tubes at kg/s and 290 K and is heated by condensing saturated steam at 1 atm on the outer surface of tubes. The convection coefficient of the saturated steam is 10,000 W/m² ·K. Please use NTU method to determine the water outlet temperature. Hint: (1) please use the Dittus-Boelter correlation to determine the internal convection coeff hị; (2) Assuming thin wall tubes and ignore the conduction resistance of the tube walls; (3) F use Table A.6 to obtain all thermo-physical properties; (4) based on Table 11.3, choo: appropriate equation to obtain ɛ from NTU.

A feed-water heater that supplies a boiler consists of a shell-and-tube heat exchanger with o1 shell pass and two tube passes. One hundred thin-walled tubes each have a diameter of 20 m and a length (per pass) of 2 m. Under normal operating conditions water enters the tubes at kg/s and 290 K and is heated by condensing saturated steam at 1 atm on the outer surface of tubes. The convection coefficient of the saturated steam is 10,000 W/m² ·K. Please use NTU method to determine the water outlet temperature. Hint: (1) please use the Dittus-Boelter correlation to determine the internal convection coeff hị; (2) Assuming thin wall tubes and ignore the conduction resistance of the tube walls; (3) F use Table A.6 to obtain all thermo-physical properties; (4) based on Table 11.3, choo: appropriate equation to obtain ɛ from NTU.

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 10.32P

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