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Investigate the drag forces produced at the turbulent boundary layers in a moving aircraft
methods for reducing drag
See the technological advancement in redesigning the bicycle wheel
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drag

fluid mechanics
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Also known as: drag force
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Investigate the drag forces produced at the turbulent boundary layers in a moving aircraft
Investigate the drag forces produced at the turbulent boundary layers in a moving aircraftLearn how a wind tunnel is used to investigate the drag forces that are produced at turbulent boundary layers.
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drag, force exerted by a fluid stream on any obstacle in its path or felt by an object moving through a fluid. Its magnitude and how it may be reduced are important to designers of moving vehicles, ships, suspension bridges, cooling towers, and other structures. Drag forces are conventionally described by a drag coefficient, defined irrespective of the shape of the body. Dimensional analysis reveals that the drag coefficient depends on the Reynolds number; the precise dependence must be elucidated experimentally and can be used to predict the drag forces experienced by other bodies in other fluids at other velocities. Engineers use this principle of dynamic similarity when they apply results obtained with a model structure to predict the behaviour of other structures. See also friction; streamline.

This article was most recently revised and updated by Robert Lewis.