A stainless steel ball (? = 8055 kg/m3 , CP = 480 J/Kg? K ) of...

A stainless steel ball (? = 8055 kg/m³ , C_P = 480 J/Kg? K ) of diameter D = 15cm is removed from the oven at a uniform temperature of 350 Degrees C. The ball is then subjected to the flow of air at 1 atm pressure and 30 degrees C with a velocity of 6m/s. The surface temperature of the ball eventually drops to 250 degrees 250 degrees C. Determine the average convection heat transfer coefficient during this cooling process and estimate how long this process has taken. The solution should be h = 25.12 W/m2 C and time = 1425 seconds according to the professor.

Expert Solution

samet mamat answered 3 years ago

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