Determine net radiation heat transfer per m2 for two infinite parallel plates held at temperature of 800 K and 500 K respectively. Emissivities of hot and cold plates are 0.6 and 0.4 respectively. Now it is intended to reduce the heat transfer to 40% of original value by placing a radiation shied between the plates. Calculate the emissivity of the shield and its equilibrium temperature.

Determine net radiation heat transfer per m2 for two infinite parallel plates held at temperature of 800 K and 500 K respectively. Emissivities of hot and cold plates are 0.6 and 0.4 respectively. Now it is intended to reduce the heat transfer to 40% of original value by placing a radiation shied between the plates. Calculate the emissivity of the shield and its equilibrium temperature.

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 1.24P: Two large parallel plates with surface conditions approximating those of a blackbody are maintained...

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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

Determine net radiation heat transfer per m2

for two infinite parallel plates

held at temperature of 800 K and 500 K respectively. Emissivities of hot

and cold plates are 0.6 and 0.4 respectively. Now it is intended to reduce

the heat transfer to 40% of original value by placing a radiation shied

between the plates. Calculate the emissivity of the shield and its

equilibrium temperature.

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