Centrifugale

Centrifugale is the Italian term used to describe things related to or producing a force that acts outward from the center of a rotating system. In physics, the outward effect is commonly referred to as the centrifugal force, a fictitious force that appears when analyzing motion from a rotating reference frame. In an inertial frame, the outward tendency of moving masses is explained by inertia requiring an inward centripetal force to keep them on a circular path.

The word derives from Latin centrum, meaning center, and fugere, meaning to flee. In everyday and engineering usage, the concept is applied to devices and processes that rely on rotation to separate, move, or stabilize materials.

Common applications include centrifuges, which use high rotational speeds to separate components of a mixture by density, such as in medical, research, and industrial settings. Centrifuges create large outward accelerations on sample contents, which, under the right conditions, cause denser components to settle differently than lighter ones. Other examples are centrifugal pumps and centrifugal fans, which move fluids or air by imparting outward velocity to a rotating impeller, and centrifugal brakes, which use rotating mass to generate resistive forces.

In technical texts, centrifugal effects are distinguished from centripetal effects: the centripetal force acts inward to keep an object on a curved path, while the centrifugal description refers to the outward appearance of motion within a rotating frame.

See also: centrifugal force, centripetal force, centrifuge.