Water (cp=4180 J/kg K) is to be heated by hot air (cp= 1010 J/kg K) in a double pipe counter flow heat exchanger. Air enters the heat exchanger at 70 °C at a rate of 0.5 kg/s, while water enters at 18 °C at a rate of 0.02 kg/s. The overall heat transfer coefficient is 60 W/m² K and the overall heat transfer area is 0.5 m². (a) Determine the outlet temperature of the water. (b) Determine the outlet temperature of the air. (Ans: 33.4 °C kg/s; 67.5 °C)

Water (cp=4180 J/kg K) is to be heated by hot air (cp= 1010 J/kg K) in a double pipe counter flow heat exchanger. Air enters the heat exchanger at 70 °C at a rate of 0.5 kg/s, while water enters at 18 °C at a rate of 0.02 kg/s. The overall heat transfer coefficient is 60 W/m² K and the overall heat transfer area is 0.5 m². (a) Determine the outlet temperature of the water. (b) Determine the outlet temperature of the air. (Ans: 33.4 °C kg/s; 67.5 °C)

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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