1. 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.

1. 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.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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