A counter-flow double-pipe heat exchanger is to heat water from 29ºC to 90ºC at a rate of 1.5 kg/s. The heating is to be accomplished by hot liquid available at 180ºC at a mass flow rate of 2.3 kg/s. The inner tube is thin-walled and has a diameter of 18 mm. If the overall heat transfer coefficient of the heat exchanger is 760 W/m2ºC, determine the length of the heat exchanger required to achieve the desired heating. The specific heats of water and hot fluid are 4.22 and 4.35 kJ/kg ºC, respectively.

A counter-flow double-pipe heat exchanger is to heat water from 29ºC to 90ºC at a rate of 1.5 kg/s. The heating is to be accomplished by hot liquid available at 180ºC at a mass flow rate of 2.3 kg/s. The inner tube is thin-walled and has a diameter of 18 mm. If the overall heat transfer coefficient of the heat exchanger is 760 W/m2ºC, determine the length of the heat exchanger required to achieve the desired heating. The specific heats of water and hot fluid are 4.22 and 4.35 kJ/kg ºC, respectively.

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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