b) The fuselage of an aeroplane consists of the following three layers: the outer layer made from aluminium alloy of a thickness 20 mm, the middle layer having convection heat transfer coefficient, h of 10 W/m2°C and an inner layer of plastic of a thickness 40 mm. If the temperature outside the aeroplane is -60 degrees centigrade at a high altitude and the inside of the fuselage is to be maintained at +20 degrees centigrade, find: i) The heat loss per unit area (Note: Area = 1 m²) ii) The temperature at the common surfaces. Thermal conductivity, k values are: Aluminium alloy = 4 W/m °C Plastic layer = 0.5 W/m °C

b) The fuselage of an aeroplane consists of the following three layers: the outer layer made from aluminium alloy of a thickness 20 mm, the middle layer having convection heat transfer coefficient, h of 10 W/m2°C and an inner layer of plastic of a thickness 40 mm. If the temperature outside the aeroplane is -60 degrees centigrade at a high altitude and the inside of the fuselage is to be maintained at +20 degrees centigrade, find: i) The heat loss per unit area (Note: Area = 1 m²) ii) The temperature at the common surfaces. Thermal conductivity, k values are: Aluminium alloy = 4 W/m °C Plastic layer = 0.5 W/m °C

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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Question

b) The fuselage of an aeroplane consists of the following three layers: the outer layer made from aluminium alloy of a
thickness 20 mm, the middle layer having convection heat transfer coefficient, h of 10 W/m2°C and an inner layer of
plastic of a thickness 40 mm. If the temperature outside the aeroplane is -60 degrees centigrade at a high altitude and
the inside of the fuselage is to be maintained at +20 degrees centigrade, find:
i)
The heat loss per unit area (Note: Area = 1 m²)
ii)
The temperature at the common surfaces.
Thermal conductivity, k values are:
Aluminium alloy
= 4 W/m °C
Plastic layer
= 0.5 W/m °C

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