Two disks are oriented on parallel planes separated by a distance of 10 inches and directly opposed (see Figure). The disk to the right (blue) is 4 inches in dimeter and at a temperature of 500 °F. The disk to the left (orange) has an inner ring cut out such as it has a hole of 2.5 inches. The outside disk is still 4 inches. The entire geometry to the left is an annular geometry. The surface temperature of the disk to the left is 210 °F. Consider the two disks to 4 in 2 210 °F 2.5 in 4 in 500°F 10 inches be black bodies and assume that the areas of disks are similar to these of circles, answer the following: 1. What is the view factor from left disk (surfaces 2+3) to right disk (surface 1)? Hint: Use Figure 17.2-7. Call that F(2+3)-1 2. What is the view factor from right disk to left disk? F1-(2+3) 3. What is the view factor between hole (surface 3) and disk 1? F31 4. What is the view factor from disk 1 to the hole? F13 5. What is the view factor from disk 1 to the solid part of disk 2+3? F12 6. Find the heat exchange between the two disks. The Stefan Boltzmann constant o is btu 0.1714 × 10-8 and °R=°F+459.67 hr.ft2.R4

Two disks are oriented on parallel planes separated by a distance of 10 inches and directly opposed (see Figure). The disk to the right (blue) is 4 inches in dimeter and at a temperature of 500 °F. The disk to the left (orange) has an inner ring cut out such as it has a hole of 2.5 inches. The outside disk is still 4 inches. The entire geometry to the left is an annular geometry. The surface temperature of the disk to the left is 210 °F. Consider the two disks to 4 in 2 210 °F 2.5 in 4 in 500°F 10 inches be black bodies and assume that the areas of disks are similar to these of circles, answer the following: 1. What is the view factor from left disk (surfaces 2+3) to right disk (surface 1)? Hint: Use Figure 17.2-7. Call that F(2+3)-1 2. What is the view factor from right disk to left disk? F1-(2+3) 3. What is the view factor between hole (surface 3) and disk 1? F31 4. What is the view factor from disk 1 to the hole? F13 5. What is the view factor from disk 1 to the solid part of disk 2+3? F12 6. Find the heat exchange between the two disks. The Stefan Boltzmann constant o is btu 0.1714 × 10-8 and °R=°F+459.67 hr.ft2.R4

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 1.31P: A spherical communications satellite, 2 m in diameter, is placed in orbit around the earth. The...

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