Exhaust gases from a power plant are used to preheat air in a cross- flow heat exchanger. The exhaust gases enter the heat exchanger at 450°C and leave at 200°C. The air enters the heat exchanger at 70°C, leaves at 250°C, and has a mass flow rate of 10 kg/s. Assume the properties of the exhaust gases can be approximated by those of air. The overall heat transfer coefficient of the heat exchanger is 154 W/m²K. Calculate the heat exchanger surface area required if the air is unmixed and the exhaust gases are mixed Cpair= 1030 J/kg k Power plant Exhaust in, 450°C Exhmest gases Heat exchanger Air in, 70°C Air intak

Exhaust gases from a power plant are used to preheat air in a cross- flow heat exchanger. The exhaust gases enter the heat exchanger at 450°C and leave at 200°C. The air enters the heat exchanger at 70°C, leaves at 250°C, and has a mass flow rate of 10 kg/s. Assume the properties of the exhaust gases can be approximated by those of air. The overall heat transfer coefficient of the heat exchanger is 154 W/m²K. Calculate the heat exchanger surface area required if the air is unmixed and the exhaust gases are mixed Cpair= 1030 J/kg k Power plant Exhaust in, 450°C Exhmest gases Heat exchanger Air in, 70°C Air intak

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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Concept explainers

Heat Exchangers

Heat exchangers are the types of equipment that are primarily employed to transfer the thermal energy from one fluid to another, provided that one of the fluids should be at a higher thermal energy content than the other fluid.

Heat Exchanger

The heat exchanger is a combination of two words ''Heat'' and ''Exchanger''. It is a mechanical device that is used to exchange heat energy between two fluids.

Question

Exhaust gases from a power plant are used to preheat air in a cross-
flow heat exchanger. The exhaust gases enter the heat exchanger at
450°C and leave at 200°C. The air enters the heat exchanger at
70°C, leaves at 250°C, and has a mass flow rate of 10 kg/s. Assume
the properties of the exhaust gases can be approximated by those of
air. The overall heat transfer coefficient of the heat exchanger is
154 W/m²K. Calculate the heat exchanger surface area required if
the air is unmixed and the exhaust gases are mixed
.CPair = 1030 J/kg k
Power plant
Exhaust
in, 450°C
Exhaust gases
Heat exchanger
Air in, 70°C
Air out, 250 ℃
Air intakes
E
Out

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