7. An oil heater heats 100 kg per minute of oil from 30°C to 100°C in a counter-flow heat exchanger. The average specific heat of the oil is 2.5 kJ/kg- C. Exhaust gases used for heating enter the heater with an average specific heat of 1 kJ/kg-°C, a mass flow rate of 200 kg/min and an initial temperature of 200°C. The overall heat transfer coefficient is 80 W/m² -°C. Determine the heating surface area in m².

7. An oil heater heats 100 kg per minute of oil from 30°C to 100°C in a counter-flow heat exchanger. The average specific heat of the oil is 2.5 kJ/kg- C. Exhaust gases used for heating enter the heater with an average specific heat of 1 kJ/kg-°C, a mass flow rate of 200 kg/min and an initial temperature of 200°C. The overall heat transfer coefficient is 80 W/m² -°C. Determine the heating surface area in 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.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.8P

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