A spherical fuel element has a center temperature of 3600 F. The fuel element is covered by two layers of coating. The fuel ball is cooled by helium. Find the rate of heat transfer. Data: rfuel = 0.5 in, r1 = 0.7 in, r2 = 0.9 in. kfuel = 2 Btu/ft·h·F, kcoating = 7 Btu/ft·h·F, Tf = 700 F and h = 5000 Btu/ft·h·F. [Ans.: 4100 Btu/h].

A spherical fuel element has a center temperature of 3600 F. The fuel element is covered by two layers of coating. The fuel ball is cooled by helium. Find the rate of heat transfer. Data: rfuel = 0.5 in, r1 = 0.7 in, r2 = 0.9 in. kfuel = 2 Btu/ft·h·F, kcoating = 7 Btu/ft·h·F, Tf = 700 F and h = 5000 Btu/ft·h·F. [Ans.: 4100 Btu/h].

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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.3DP

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