A body at 1100ºc in a black surrounding at 550ºc has emissivity of 0.4 at 1100ºc and emissivity 0.7 at 550ºc. calculate the rate of heat loss by radiation per unit surface area; i) when the body is assumed to be grey with emissivity 0.4 ii) when the body is not grey. (assume absorptivity is independent of the surface temperature)

A body at 1100ºc in a black surrounding at 550ºc has emissivity of 0.4 at 1100ºc and emissivity 0.7 at 550ºc. calculate the rate of heat loss by radiation per unit surface area; i) when the body is assumed to be grey with emissivity 0.4 ii) when the body is not grey. (assume absorptivity is independent of the surface 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.

Chapter11: Heat Transfer By Radiation

Section: Chapter Questions

Problem 11.34P

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