Spoked flywheel

Flywheel from stationary engine. Note the castellated rim which was used to rotate the engine to the correct starting position by means of a lever.

A Landini tractor with massive flywheel

A flywheel is a rotating disk used as a storage device for kinetic energy. Flywheels resist changes in their rotational speed, which helps steady the rotation of the shaft when a fluctuating torque is exerted on it by its power source such as a piston-based (reciprocating) engine, or when the load placed on it is intermittent (such as a piston pump). Flywheels can be used to produce very high power pulses as needed for some experiments, where drawing the power from the public network would produce unacceptable spikes. A small motor can accelerate the flywheel between the pulses. Recently, flywheels have become the subject of extensive research as power storage devices for uses in vehicles; see flywheel energy storage. Flywheel drive is common in low-cost toys. Spoked flywheel http://www. ... Spoked flywheel http://www. ... Image File history File linksMetadata Size of this preview: 800 × 600 pixels Full resolution (1600 × 1200 pixel, file size: 522 KB, MIME type: image/jpeg) Author Gregorydavid 18:49, 19 December 2006 (UTC) Permission is granted to copy, distribute and/or modify this document under the terms of the GNU... Image File history File linksMetadata Size of this preview: 800 × 600 pixels Full resolution (1600 × 1200 pixel, file size: 522 KB, MIME type: image/jpeg) Author Gregorydavid 18:49, 19 December 2006 (UTC) Permission is granted to copy, distribute and/or modify this document under the terms of the GNU... A stationary engine is an engine that does not move. ... Image File history File links Size of this preview: 651 × 600 pixels Full resolution (1041 × 959 pixel, file size: 344 KB, MIME type: image/jpeg) Photographed by Späth Chr. ... Image File history File links Size of this preview: 651 × 600 pixels Full resolution (1041 × 959 pixel, file size: 344 KB, MIME type: image/jpeg) Photographed by Späth Chr. ... Landini VL30 Landini was founded by Giovanni Landini and had just started making tractors in 1925 when Giovanni Landini died preventing the completion of the first prototype Landini trator. ... Flywheel is an American drama film released in 2003. ... The kinetic energy of an object is the extra energy which it possesses due to its motion. ... Rotational speed (sometimes called speed of revolution) indicates for example how fast the motor is running. ... It has been suggested that this article or section be merged with Moment (physics). ... piston + connecting rod Components of a typical, four stroke cycle, DOHC piston engine. ... Components of a typical, four stroke cycle, DOHC piston engine. ... An engine is something that produces an effect from a given input. ... An electrically driven pump (electropump) for waterworks near the Hengsteysee, Germany. ... NASA G2 flywheel Flywheel Energy Storage (FES) works by accelerating a rotor to a very high speed and maintaining the energy in the system as inertial energy. ...

A momentum wheel is a type of flywheel useful in satellite pointing operations, in which the flywheels are used to point the satellite's instruments in the correct directions without the use of thrusters. Gyroscope of the International Space Station A momentum wheel or reaction wheel is a type of flywheel used primarily by spacecraft to change their angular momentum without using fuel for rockets or other reaction devices. ...

The kinetic energy of a rotating flywheel is The kinetic energy of an object is the extra energy which it possesses due to its motion. ...

where I is the moment of inertia of the mass about the center of rotation and ω (omega) is the angular velocity in radians per second. Note the similarity of the above formula to the kinetic energy formula , where linear velocity v is comparable to the rotational velocity, and the mass is comparable to the rotational inertia. A flywheel is more effective when its inertia is larger, as when its mass is located farther from the center of rotation either due to a more massive rim or due to a larger diameter. The moment of inertia of a uniform cylinder, for instance, is , where M is the mass and R is the radius. Moment of inertia, also called mass moment of inertia and, sometimes, the angular mass, (SI units kg m², Former British units slug ft2) quantifies the rotational inertia of a rigid body, i. ... Unsolved problems in physics: What causes anything to have mass? The U.S. National Prototype Kilogram, which currently serves as the primary standard for measuring mass in the U.S. Mass is the property of a physical object that quantifies the amount of matter and energy it is equivalent to. ... Look up Ω, ω in Wiktionary, the free dictionary. ... Angular velocity describes the speed of rotation and the orientation of the instantaneous axis about which the rotation occurs. ... In mathematics and physics, the radian is a unit of angle measure. ...

In application of flywheels in vehicles, the phenomenon of precession has to be considered. A rotating flywheel responds to any momentum that tends to change the direction of it's axis of rotation by a resulting precession rotation. A vehicle with a vertical-axis flywheel would experience a lateral momentum when passing the top of a hill or the bottom of a valley (roll momentum in response to a pitch change). Two counter-rotating flywheels may be needed to eliminate this effect. Precession of a gyroscope Precession refers to a change in the direction of the axis of a rotating object. ... Look up roll in Wiktionary, the free dictionary. ... Pitch may refer to: Look up Pitch in Wiktionary, the free dictionary. ...

The flywheel has been used since ancient times, the most common traditional example being the potter's wheel. In the Industrial Revolution, James Watt contributed to the development of the flywheel in the steam engine, and his contemporary James Pickard used a flywheel combined with a crank to transform reciprocating into rotary motion. Classic potters kick-wheel at Erfurt, Germany The potters wheel, also known as the potters lathe, is a machine used in the shaping of round ceramic wares. ... A Watt steam engine. ... James Watt James Watt (19 January 1736 – 19 August 1819) was a Scottish inventor and engineer whose improvements to the steam engine were fundamental to the changes wrought by the Industrial Revolution. ... // The term steam engine may also refer to an entire railroad steam locomotive. ... James Pickard was an English inventor. ... A crank is a bent portion of an axle, or shaft, or an arm keyed at right angles to the end of a shaft, by which motion is imparted to or received from it; also used to change circular into reciprocating motion, or reciprocating into circular motion. ...

Also, it shold be noted that flywheels can be used as weapons. For instance, on the show Robot Wars, heavy flywheels with attached claws or hammers can be used to rip the armor of other robots to shreds. Robot Wars was a British game show broadcast on BBC Two from 1997 until 2002, with a final series broadcast on Five in 2003. ...

In the world of venture capital, the term "flywheel" is used to represent the recurrent, margin-generating heart of a business. Image File history File links Leonardo-Flywheel. ...

History

Simple flywheel in motion. Constructed based on drawings by Leonardo da Vinci

The principle of the flywheel is already found in the Neolithic spindle and the potter's wheel.^[1] The flywheel as a general mechanical device for equalizing the speed of rotation is, according to the American medievalist Lynn White, first recorded in the De diversibus artibus (On various arts) of the German artisan Theophilus Presbyter (ca. 1070-1125) who records applying the device in several of his machines.^{[1] [2]} Image File history File links Leonardo-Flywheel-screenshot. ... Image File history File links Leonardo-Flywheel-screenshot. ... The Mona Lisa Leonardo di ser Piero da Vinci (April 15, 1452 – May 2, 1519) was an Italian polymath: scientist, mathematician, engineer, inventor, anatomist, painter, sculptor, architect, musician, and writer. ... The word spindle might (or might not) have several meanings: A spindle (shrub), a poisonous shrub or small tree of the genus Euonymus. ... Classic potters kick-wheel at Erfurt, Germany The potters wheel, also known as the potters lathe, is a machine used in the shaping of round ceramic wares. ... Lynn Townsend White, Jr. ... Theophilus Presbyter (approx. ...

See also

• List of energy topics
• Gyroscope
• Momentum wheel
• Regenerative braking
• Flywheel energy storage
• Inductor

This is a list of energy topics which identifies articles and categories that relate to energy. ... A gyroscope For other uses, see Gyroscope (disambiguation). ... Gyroscope of the International Space Station A momentum wheel or reaction wheel is a type of flywheel used primarily by spacecraft to change their angular momentum without using fuel for rockets or other reaction devices. ... Regenerative braking is any technology which allows a vehicle to recapture and store part of the kinetic energy that would otherwise be lost to heat when braking. ... NASA G2 flywheel Flywheel Energy Storage (FES) works by accelerating a rotor to a very high speed and maintaining the energy in the system as inertial energy. ... An inductor is a passive electrical device employed in electrical circuits for its property of inductance. ...

References