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…

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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You can neglect radiation at the bottom of the plate; the bottom side of the plate has water flowing underneath it. Often, when dealing with liquids (rather than gases), one can neglect radiation because heat transfer due to convection is so much larger (liquids tend to have higher convection coefficient values than gases).
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An object of irregular shape has a characteristic length of L = 1 m and is maintained at a uniform surface temperature of Ts = 375 K. When placed in atmospheric air at a temperature of T = 300 K and moving with a velocity of V = 100 m/s, the average heat flux from the surface to the air is 20,000 W/m². If a second object of the same shape, but with a characteristic length of L = 5 m, is maintained at a surface temperature of Ts 375 K and is placed in atmospheric air at T = 300 K, what will the value of the average convection coefficient be if the air velocity is V = 20 m/s? = h₂ = = || i W/m².K
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