18th-century British engineer John Smeaton established that the amount of pressure on the object depends on how fast the fluid moves over it. Following the Smeaton relationship, the air pressure on a wing depends on how fast the air is moving over the wing. When measuring pressure in a flow, the density of the fluid involved—air in this case—must be accounted for with a multiplying factor called a coefficient. A value for air of 0.005 was derived in the mid-18th century and named after Smeaton.
Image Number: WEB13530-2013
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