9. Consider the three-surface enclosure shown. The lower plate (A1) is a black disk of 200- mm diameter and is supplied with a heat rate of 10,000 W. The upper plate (A2), a disk coaxial to A₁, is a diffuse, gray surface with 2 = 0.8 and is maintained at T₂ = 473 K. The diffuse, gray sides between the plates are perfectly insulated. Assume convection heat transfer is negligible. (40 points) (a) Determine the operating temperature of the lower plate, T₁. (b) Determine the temperature of the insulated side, T3. D= 0.2 m - A2, T₂ = 473 K, &₂ = 0.8 L = 0.2 m A3, T3, insulated P = 10,000 W A₁, T₁, black surface

9. Consider the three-surface enclosure shown. The lower plate (A1) is a black disk of 200- mm diameter and is supplied with a heat rate of 10,000 W. The upper plate (A2), a disk coaxial to A₁, is a diffuse, gray surface with 2 = 0.8 and is maintained at T₂ = 473 K. The diffuse, gray sides between the plates are perfectly insulated. Assume convection heat transfer is negligible. (40 points) (a) Determine the operating temperature of the lower plate, T₁. (b) Determine the temperature of the insulated side, T3. D= 0.2 m - A2, T₂ = 473 K, &₂ = 0.8 L = 0.2 m A3, T3, insulated P = 10,000 W A₁, T₁, black surface

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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