In
mechanics
Mechanics () is the area of physics concerned with the relationships between force, matter, and motion among Physical object, physical objects. Forces applied to objects may result in Displacement (vector), displacements, which are changes of ...
and
aerodynamics
Aerodynamics () is the study of the motion of atmosphere of Earth, air, particularly when affected by a solid object, such as an airplane wing. It involves topics covered in the field of fluid dynamics and its subfield of gas dynamics, and is an ...
, the drag area of an object represents the effective size of the object as it is "seen" by the fluid flow around it.
The drag area is usually expressed as a product
where
is a representative area of the object, and
is the
drag coefficient, which represents what shape it has and how streamlined it is.
The drag coefficient plays a role in
Reynold's drag equation,
:
Here,
is the drag force,
the density of the fluid, and
the speed of the object relative to the fluid.
See also
*
Drag (physics)
In fluid dynamics, drag, sometimes referred to as fluid resistance, is a force acting opposite to the direction of motion of any object moving with respect to a surrounding fluid. This can exist between two fluid layers, two solid surfaces, or b ...
*
Automobile drag coefficient#Drag area
*
Zero-lift drag coefficient
In aerodynamics, the zero-lift drag coefficient C_ is a dimensionless parameter which relates an aircraft's zero-lift drag force to its size, speed, and flying altitude.
Mathematically, zero-lift drag coefficient is defined as C_ = C_D - C_, whe ...
References
Drag (physics)
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