In the design of a cold-storage warehouse, the specifications call for a maximum heat transfer through the warehouse walls of 30,000 joules per hour per square meter of wall when there is a 30°C temperature difference between the inside surface and the outside surface of the insulation. The two insulation materials being considered are as follows: Conductivity (J-m/m²-°C-hr) Cost per Cubic Meter $12.50 Insulation Material Rock wool 140 Foamed insulation 14.00 110 The basic equation for heat conduction through a wall is: K(AT) where Q=heat transfer, in J/hr/m2 of wall K=conductivity in J-m/m²-°C-hr AT =difference in temperature between the two surfaces, in °C L=thickness of insulating material, in meters %3D %3D Which insulation material should be selected?

In the design of a cold-storage warehouse, the specifications call for a maximum heat transfer through the warehouse walls of 30,000 joules per hour per square meter of wall when there is a 30°C temperature difference between the inside surface and the outside surface of the insulation. The two insulation materials being considered are as follows: Conductivity (J-m/m²-°C-hr) Cost per Cubic Meter $12.50 Insulation Material Rock wool 140 Foamed insulation 14.00 110 The basic equation for heat conduction through a wall is: K(AT) where Q=heat transfer, in J/hr/m2 of wall K=conductivity in J-m/m²-°C-hr AT =difference in temperature between the two surfaces, in °C L=thickness of insulating material, in meters %3D %3D Which insulation material should be selected?

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

In the design of a cold-storage warehouse, the specifications call for a maximum heat transfer
through the warehouse walls of 30,000 joules per hour per square meter of wall when there is a
30°C temperature difference between the inside surface and the outside surface of the insulation.
The two insulation materials being considered are as follows:
Conductivity
(J-m/m²-°C-hr)
Cost per Cubic Meter
$12.50
14.00
Insulation Material
140
Rock wool
Foamed insulation
110
The basic equation for heat conduction through a wall is:
K(AT)
Q =
Q=heat transfer, in J/hr/m² of wall
K=conductivity in J-m/m2-°C-hr
AT =difference in temperature between the two surfaces, in °C
L=thickness of insulating material, in meters
where
Which insulation material should be selected?

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