A counter-flow heat exchanger is used to cool 2200 kg/hr of oil (cp=2.5 kJ/kgK), from 100°C to 35°C by the use of water entering at 17°C. If the overall heat transfer coefficient is expected to be 1.5 kW/m²k, make calculations for the water flow rate, the surface area required, and the effectiveness of the heat exchanger. Presume that the exit temperature of the water is not to exceed 85°C. Use the NTU-effectiveness approach.

A counter-flow heat exchanger is used to cool 2200 kg/hr of oil (cp=2.5 kJ/kgK), from 100°C to 35°C by the use of water entering at 17°C. If the overall heat transfer coefficient is expected to be 1.5 kW/m²k, make calculations for the water flow rate, the surface area required, and the effectiveness of the heat exchanger. Presume that the exit temperature of the water is not to exceed 85°C. Use the NTU-effectiveness approach.

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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