A 20ft x 20ft metal building has a steel roof that reaches a temperature of 140o...

A 20ft x 20ft metal building has a steel roof that reaches a temperature of 140^o F on a hot day. A cool front then moves in such that air at 60^oF sweeps horizontally across the roof at a velocity of 10 ft/s. Assuming the roof temperature remains at a constant 140^oF for a time, determine:

a) the point at which the flow becomes turbulent (in feet)

b) the average heat transfer coefficient for the roof (in BTU/hr*ft^2*F)

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Expert Solution

samet mamat answered 1 year ago

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