Two large parallel surfaces (surface 1 and surface 2) kept at constant surface temperature of T= 300 °C and T2= 100 °C. The two surfaces have emissivity of ɛ1= 0.8 and E2= 0.5 respectively. The top surface (surface 2) is cooled by convective heat transfer with surrounding air temperature of 20 °C. The bottom surface (surface 1) is well insulated at the backside. Assume the surfaces are diffuse and gray, and the space between the surfaces is vacuum. a. Calculate the radiation heat transfer between the surfaces per unit area [W/m?].

Two large parallel surfaces (surface 1 and surface 2) kept at constant surface temperature of T= 300 °C and T2= 100 °C. The two surfaces have emissivity of ɛ1= 0.8 and E2= 0.5 respectively. The top surface (surface 2) is cooled by convective heat transfer with surrounding air temperature of 20 °C. The bottom surface (surface 1) is well insulated at the backside. Assume the surfaces are diffuse and gray, and the space between the surfaces is vacuum. a. Calculate the radiation heat transfer between the surfaces per unit area [W/m?].

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 11.65P

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