A thin-walled double-pipe heat exchanger is to be used to cool oil (cp= 2500 J/kg-K) from 80°C to 50°C at a rate of 5 kg/s by water (cp= 4200 J/kg-K) that enters at 20°C at a rate of 2 kg/s. The diameter and length of the tube considered for the heat exchanger is 2.5 cm and 2 meters. The convective heat transfer coefficients for the oil and water are assumed to be ho = 400; and W m²c hw=600- respectively. W m² a. Determine if a parallel or counter flow heat exchanger should be used in this case (tell reason and show calculation) b. Using LMTD method, determine the number of pipes required for the heat exchanger

A thin-walled double-pipe heat exchanger is to be used to cool oil (cp= 2500 J/kg-K) from 80°C to 50°C at a rate of 5 kg/s by water (cp= 4200 J/kg-K) that enters at 20°C at a rate of 2 kg/s. The diameter and length of the tube considered for the heat exchanger is 2.5 cm and 2 meters. The convective heat transfer coefficients for the oil and water are assumed to be ho = 400; and W m²c hw=600- respectively. W m² a. Determine if a parallel or counter flow heat exchanger should be used in this case (tell reason and show calculation) b. Using LMTD method, determine the number of pipes required for the heat exchanger

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 7.46P

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