An oil heater heats 60 kg per minute of oil from 28°C to 70°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 100 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.

An oil heater heats 60 kg per minute of oil from 28°C to 70°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 100 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.

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter44: Geothermal Heat Pumps

Section: Chapter Questions

Problem 16RQ: Explain why a waterless, earth-coupled, closed-loop geo-thermal heat pump system is more efficient...

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