Drag coefficient Definition and 90 Threads

In fluid dynamics, the drag coefficient (commonly denoted as:




c

d




{\displaystyle c_{d}}
,




c

x




{\displaystyle c_{x}}
or




c

w




{\displaystyle c_{w}}
) is a dimensionless quantity that is used to quantify the drag or resistance of an object in a fluid environment, such as air or water. It is used in the drag equation in which a lower drag coefficient indicates the object will have less aerodynamic or hydrodynamic drag. The drag coefficient is always associated with a particular surface area.The drag coefficient of any object comprises the effects of the two basic contributors to fluid dynamic drag: skin friction and form drag. The drag coefficient of a lifting airfoil or hydrofoil also includes the effects of lift-induced drag. The drag coefficient of a complete structure such as an aircraft also includes the effects of interference drag.

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