12.47 A diffuse, opaque surface at 700 K has spectral emis- sivities of ε = 0 for 0 ≤3 μm, ε = 0.5 for 3 μm <≤10 μm, and ε = 0.9 for 10 μm << ∞. A radiant flux of 1000 W/m², which is uniformly dis- tributed between 1 and 6 μm, is incident on the sur- face at an angle of 30° relative to the surface normal. q" = 1000 W/m² 30% L= 1 m (wri.w/M), b 200 1 6 λ (μη) Calculate the total radiant power from a 10-4 m² area of the surface that reaches a radiation detector posi- tioned along the normal to the area. The aperture of the detector is 105 m², and its distance from the sur- face is 1 m.

12.47 A diffuse, opaque surface at 700 K has spectral emis- sivities of ε = 0 for 0 ≤3 μm, ε = 0.5 for 3 μm <≤10 μm, and ε = 0.9 for 10 μm << ∞. A radiant flux of 1000 W/m², which is uniformly dis- tributed between 1 and 6 μm, is incident on the sur- face at an angle of 30° relative to the surface normal. q" = 1000 W/m² 30% L= 1 m (wri.w/M), b 200 1 6 λ (μη) Calculate the total radiant power from a 10-4 m² area of the surface that reaches a radiation detector posi- tioned along the normal to the area. The aperture of the detector is 105 m², and its distance from the sur- face is 1 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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.26P: 1.26 Repeat Problem 1.25 but assume that the surface of the storage vessel has an absorbance (equal...

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Heat Transfer Question is image
The last portion asks you for "net radiant heat flux to the surface", meaning that positive net radiative heat flux means in and negative net radiative heat flux means out. This is opposite the typical sign convention - be aware of this
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