A stream of ammonia is cooled from 100oC to 20oC at a rate of 180 kg/hr in the tube side of a double-pipe counter-flow heat exchanger. Water enters the heat exchanger at 10oC at a rate of 250 kg/hr. The outside diameter of the inner tube is 3 cm and the length of the pipe is 7m. Using the log-mean temperature difference, calculate the overall heat transfer coefficient (U) for the heat exchanger. Determine the log-mean temperature difference. Determine the heat transfer coefficient for the heat exchanger. Cp for ammonia is 5234J/kgK and cp for water is 4180J/kgK.

A stream of ammonia is cooled from 100oC to 20oC at a rate of 180 kg/hr in the tube side of a double-pipe counter-flow heat exchanger. Water enters the heat exchanger at 10oC at a rate of 250 kg/hr. The outside diameter of the inner tube is 3 cm and the length of the pipe is 7m. Using the log-mean temperature difference, calculate the overall heat transfer coefficient (U) for the heat exchanger. Determine the log-mean temperature difference. Determine the heat transfer coefficient for the heat exchanger. Cp for ammonia is 5234J/kgK and cp for water is 4180J/kgK.

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 10.46P

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