5. An air-to-air recovery unit uses a cross-flow heat exchange with both fluids unmixed and an air flow rate of 0.75 kg/s on both sides. The hot air enters at 400 C while the cool air enters at 20 C. Calculate the exit temperatures of (a) the hot air and (b) the cool air for U = 45 W/m2-K and a total heat exchanger area of 25 m2. *

5. An air-to-air recovery unit uses a cross-flow heat exchange with both fluids unmixed and an air flow rate of 0.75 kg/s on both sides. The hot air enters at 400 C while the cool air enters at 20 C. Calculate the exit temperatures of (a) the hot air and (b) the cool air for U = 45 W/m2-K and a total heat exchanger area of 25 m2. *

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 10.50P

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