1.7 Calculate the net rate of energy exchange by thermal radiation in a systemconsisting of two large parallel plane surfaces 1 and 2 with a surface areaof A = 4 m? each, temperatures T, of 550 K and T, of 430 K, and emissivi-ties & of 0.3 and E, of 0.8. Assume that the distance between the two planesurfaces is small compared to their dimensions.

Given data T1 = 550K T2= 430K Required Heat exchange

Answered: plane surfaces 1 and 2 - I, of 550 K…

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plane surfaces 1 and 2 - I, of 550 K and T, of 43 me that the distance betw eir dimensions.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.47P: 1.47 A flat roof is modeled as a flat plate insulated on the bottom and placed in the sunlight. If...

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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

1.7 Calculate the net rate of energy exchange by thermal radiation in a system
consisting of two large parallel plane surfaces 1 and 2 with a surface area
of A = 4 m? each, temperatures T, of 550 K and T, of 430 K, and emissivi-
ties & of 0.3 and E, of 0.8. Assume that the distance between the two plane
surfaces is small compared to their dimensions.

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