An object of irregular shape has a characteristic length of L=1 m and is maintained at a uniformsurface temperature of Ts = 400 K. When placed in atmospheric air at a temperature of T∞ =300 K and moving with a velocity of u∞ = 100 m/s, the average heat flux from the surface tothe air is 20,000 W/m2. If a second object of the same shape but with a characteristic length ofL=5 m, is maintained at a surface temperature of T₂ = 400 K and is placed in atmospheric air atToo 300 K, what will the value of the average convection coefficient be if the air velocity isU=20 m/s? (Use the average temperature of Ts and T∞ to find air properties if necessary)

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Answered: An object of irregular shape has a…

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.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.67P

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