Problem. 13–88 Two coaxial cylinders of diameters D1 = 0.10 m and D2 = 0.50 m and emissivities ε1 = 0.7 and ε2 = 0.4 are maintained at uniform temperatures of T1 = 750 K and T2 = 500 K, respectively. Now a coaxial radiation shield of diameter D3 = 0.20 m and emissivity ε3 = 0.2 is placed between the two cylinders. Determine the net rate of radiation heat transfer between the two cylinders per unit length of the cylinders and compare the result with that without the shield.

Problem. 13–88 Two coaxial cylinders of diameters D1 = 0.10 m and D2 = 0.50 m and emissivities ε1 = 0.7 and ε2 = 0.4 are maintained at uniform temperatures of T1 = 750 K and T2 = 500 K, respectively. Now a coaxial radiation shield of diameter D3 = 0.20 m and emissivity ε3 = 0.2 is placed between the two cylinders. Determine the net rate of radiation heat transfer between the two cylinders per unit length of the cylinders and compare the result with that without the shield.

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 11.22P

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