2. Two large plates parallel plates having emissivities of 0.4 and 0.6 are maintained at temperatures of 900 K and 300 K, respectively. A radiation shield having an emissivity of 0.06 on both sides is placed between the two plates. Calculate (a) the heat transfer rate per unit area if the shield was not present; (b) the heat transfer rate per unit area with the shield present; (c) the percent decrease in heat transfer if the shield is in place.

2. Two large plates parallel plates having emissivities of 0.4 and 0.6 are maintained at temperatures of 900 K and 300 K, respectively. A radiation shield having an emissivity of 0.06 on both sides is placed between the two plates. Calculate (a) the heat transfer rate per unit area if the shield was not present; (b) the heat transfer rate per unit area with the shield present; (c) the percent decrease in heat transfer if the shield is in place.

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

Radiation

Radiation can be described as the energy in the form of a particular matter or electromagnetic waves traveling in the air and can be in the form of light, sound, and heat. Radiation can be detected through special instruments like X-rays. The radiation from a cooler object is less intense as compared to the radiation from hot objects.

Question

2. Two large plates parallel plates
having emissivities of 0.4 and 0.6
are maintained at temperatures of
900 K and 300 K, respectively. A
radiation shield having an
emissivity of 0.06 on both sides is
placed between the two plates.
Calculate (a) the heat transfer
rate per unit area if the shield was
not present; (b) the heat transfer
rate per unit area with the shield
present; (c) the percent decrease
in heat transfer if the shield is in
place.

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