Consider two coaxial parallel circular disks of equal diameter D = 1 m spaced apart by 1 m, and two aligned parallel square plates (1 m * 1 m) are also spaced apart by 1 m. Determine the view factors F12 between the circular disks and the square plates. Which of the two geometries has the higher view factor value?

Consider two coaxial parallel circular disks of equal diameter D = 1 m spaced apart by 1 m, and two aligned parallel square plates (1 m * 1 m) are also spaced apart by 1 m. Determine the view factors F12 between the circular disks and the square plates. Which of the two geometries has the higher view factor value?

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 11.32P

See similar textbooks

Similar questions

11.31 A large slab of steel 0.1 m thick contains a 0.1 -m-di- ameter circular hole whose axis is normal to the surface. Considering the sides of the hole to be black, specify the rate of radiative heat loss from the hole. The plate is at 811 K, and the surroundings are at 300 K.
Two large parallel plates with surface conditions approximating those of a blackbody are maintained at 816C and 260C, respectively. Determine the rate of heat transfer by radiation between the plates in W/m2 and the radiative heat transfer coefficient in W/m2K.
Determine the total average hemispherical emissivity and the emissive power of a surface that has a spectral hemispherical emissivity of 0.8 at wavelengths less than 1.5m, 0.6 at wavelengths from 1.5to2.5m, and 0.4 at wavelengths longer than 2.5m. The surface temperature is 1111 K.
1.28 The sun has a radius of and approximates a blackbody with a surface temperature of about 5800 K. Calculate the total rate of radiation from the sun and the emitted radiation flux per square meter of surface area.
11.68 Two infinitely large, black, plane surfaces are 0.3 m apart, and the space between them is filled by an isothermal gas mixture at 811 K and atmospheric pressure. The gas mixture consists of by volume. If one of the surfaces is maintained at 278 K and the other at 1390 K, calculate (a) the effective emissivity of the gas at its temperature, (b) the effective absorptivity of the gas to radiation from the 1390 K surface, (c) the effective absorptivity of the gas to radiation from the 278 K surface, and (d) the net rate of heat transfer to the gas per square meter of surface area.
11.41 Determine the steady-state temperatures of two radiation shields placed in the evacuated space between two infinite planes at temperatures of 555 K and 278 K. The emissivity of all surfaces is 0.8.
Consider two coaxial parallel circular disks of equal diameter D that are spaced apart by a distance L. If the view factor is F12 = 0.1, without altering the diameter of the disks, determine a solution that would increase the view factor F12 by a factor of 5.
A circular cone of diameter D with a length L ispositioned on a common axis with a circular disk, also ofdiameter D, at a distance L. A cylindrical surfaceof diameter D with a length L and a circular disk, ofthe same diameter D, are oriented coaxially at a distance L Determine the view factors F12 for the two geometries. Which of the two geometries has the higher view factor value?
Consider two coaxial parallel circular disks of equal diameter D = 1.55 m spaced apart by 1.55 m, and two aligned parallel square plates (1.55 m × 1.55 m) are also spaced apart by 1.55 m. Determine the view factor F12 between the circular disks. (For coaxial parallel disks, i = 1 and j = 2.)
How can you determine the view factor F12 whenthe view factor F21 and the surface areas are available?