|
Flywheels
A flywheel is a mechanical device that uses the conservation of angular momentum to store rotational energy, a form of kinetic energy proportional to the product of its moment of inertia and the square of its rotational speed. In particular, assuming the flywheel's moment of inertia is constant (i.e., a flywheel with fixed mass and second moment of area revolving about some fixed axis) then the stored (rotational) energy is directly associated with the square of its rotational speed. Since a flywheel serves to store mechanical energy for later use, it is natural to consider it as a kinetic energy analogue of an electrical Inductor. Once suitably abstracted, this shared principle of energy storage is described in the generalized concept of an accumulator. As with other types of accumulators, a flywheel inherently smooths sufficiently small deviations in the power output of a system, thereby effectively playing the role of a low-pass filter with respect to the mechanical velocity ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flywheel Energy Storage
Flywheel energy storage (FES) works by accelerating a rotor (flywheel) to a very high speed and maintaining the energy in the system as rotational energy. When energy is extracted from the system, the flywheel's rotational speed is reduced as a consequence of the principle of conservation of energy; adding energy to the system correspondingly results in an increase in the speed of the flywheel. Most FES systems use electricity to accelerate and decelerate the flywheel, but devices that directly use mechanical energy are being developed.Torotrak Toroidal variable drive CVT , retrieved June 7, 2007. Advanced FES systems have rotors made of high strength carbon-fiber composites, suspended by magnetic bearings, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Bearing
A magnetic bearing is a type of bearing that supports a load using magnetic levitation. Magnetic bearings support moving parts without physical contact. For instance, they are able to levitate a rotating shaft and permit relative motion with very low friction and no mechanical wear. Magnetic bearings support the highest speeds of any kind of bearing and have no maximum relative speed. Active bearings have several advantages: they do not suffer from wear, have low friction, and can often accommodate irregularities in the mass distribution automatically, allowing rotors to spin around their center of mass with very low vibration. Passive magnetic bearings use permanent magnets and, therefore, do not require any input power but are difficult to design due to the limitations described by Earnshaw's theorem. Techniques using diamagnetic materials are relatively undeveloped and strongly depend on material characteristics. As a result, most magnetic bearings are active magnetic bear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gyroscope
A gyroscope (from Ancient Greek γῦρος ''gŷros'', "round" and σκοπέω ''skopéō'', "to look") is a device used for measuring or maintaining Orientation (geometry), orientation and angular velocity. It is a spinning wheel or disc in which the axis of rotation (spin axis) is free to assume any orientation by itself. When rotating, the orientation of this axis is unaffected by tilting or rotation of the mounting, due to the angular momentum#Conservation of angular momentum, conservation of angular momentum. Gyroscopes based on other operating principles also exist, such as the microchip-packaged Vibrating structure gyroscope#MEMS gyroscopes, MEMS gyroscopes found in electronic devices (sometimes called gyrometers), solid-state ring laser gyroscope, ring lasers, fibre optic gyroscopes, and the extremely sensitive quantum gyroscope. Applications of gyroscopes include inertial navigation systems, such as in the Hubble Space Telescope, or inside the steel hull of a submer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reciprocating Engine
A reciprocating engine, more often known as a piston engine, is a heat engine that uses one or more reciprocating pistons to convert high temperature and high pressure into a rotating motion. This article describes the common features of all types. The main types are: the internal combustion engine, used extensively in motor vehicles; the steam engine, the mainstay of the Industrial Revolution; and the Stirling engine for niche applications. Internal combustion engines are further classified in two ways: either a spark-ignition (SI) engine, where the spark plug initiates the combustion; or a compression-ignition (CI) engine, where the air within the cylinder is compressed, thus heating it, so that the heated air ignites fuel that is injected then or earlier.''Thermodynamics: An Engineering Approach'' by Yunus A. Cengal and Michael A. Boles Common features in all types There may be one or more pistons. Each piston is inside a cylinder, into which a gas is introduced, e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thinktank Birmingham - Trevithick Locomotive(1)
A think tank, or public policy institute, is a research institute that performs research and advocacy concerning topics such as social policy, political strategy, economics, military, technology, and culture. Most think tanks are non-governmental organizations, but some are semi-autonomous agencies within a government, and some are associated with particular political parties, businesses, or the military. Think tanks are often funded by individual donations, with many also accepting government grants. Think tanks publish articles and studies, and sometimes draft legislation on particular matters of policy or society. This information is then used by governments, businesses, media organizations, social movements, or other interest groups. Think tanks range from those associated with highly academic or scholarly activities to those that are overtly ideological and pushing for particular policies, with a wide range among them in terms of the quality of their research. Later gener ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lynn White
Lynn Townsend White Jr. (April 29, 1907 – March 30, 1987) was an American historian of technology and college president. He was an instructor in medieval history at Princeton University from 1933 to 1937, a professor at Stanford University from 1937 to 1943, president of Mills College, Oakland, California, from 1943 to 1958, and a professor at the University of California, Los Angeles from 1958 until 1987. He is best known for the controversial book ''Medieval Technology and Social Change'' (1962) and for controversial articles on religion, technology, and ecology such as "Dynamo and Virgin Reconsidered" ('' The American Scholar'', 1958) and "The Historical Roots of Our Ecologic Crisis" (''Science'', 1967). White helped to found the Society for the History of Technology and was its president from 1960 to 1962. He won the 1963 Pfizer Award for ''Medieval Technology and Social Change'' and the Leonardo da Vinci Medal in 1964. Early life and education White was born April 29 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saqiyah
A sāqiyah or saqiya (), also spelled sakia or saqia) is a mechanical water lifting device. It is also called a Persian wheel, tablia, rehat, and in Latin tympanum. It is similar in function to a scoop wheel, which uses buckets, jars, or scoops fastened either directly to a vertical wheel, or to an endless belt activated by such a wheel. The vertical wheel is itself attached by a drive shaft to a horizontal wheel, which is traditionally set in motion by animal power (oxen, donkeys, etc.) Because it is not using hydropower, the power of flowing water, the sāqiyah is different from a noria and any other type of water wheel. The sāqiyah is still used in India, Egypt and other parts of the Middle East, and in the Iberian Peninsula and the Balearic Islands. It may have been invented in Ptolemaic Kingdom of Egypt, Iran, Kingdom of Kush, Kush or India. The sāqiyah was mainly used for irrigation, but not exclusively, as the example of Qusayr 'Amra shows, where it was used at least in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Academic Press
Academic Press (AP) is an academic book publisher founded in 1941. It launched a British division in the 1950s. Academic Press was acquired by Harcourt, Brace & World in 1969. Reed Elsevier said in 2000 it would buy Harcourt, a deal completed the next year, after a regulatory review. Thus, Academic Press is now an imprint of Elsevier. Academic Press publishes reference books, serials and online products in the subject areas of: * Communications engineering * Economics * Environmental science * Finance * Food science and nutrition * Geophysics * Life sciences * Mathematics and statistics * Neuroscience * Physical sciences * Psychology Psychology is the scientific study of mind and behavior. Its subject matter includes the behavior of humans and nonhumans, both consciousness, conscious and Unconscious mind, unconscious phenomena, and mental processes such as thoughts, feel ... Well-known products include the '' Methods in Enzymology'' series and encyclopedias such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theophilus Presbyter
Theophilus Presbyter (fl. c. 1070–1125) is the pseudonymous author or compiler of a Latin text containing detailed descriptions of various medieval arts, a text commonly known as the ''Schedula diversarum artium'' ("List of various arts") or ''De diversis artibus'' ("On various arts"), probably first compiled between 1100 and 1120. Work The oldest manuscript copies of ''De diversis artibus'' are found in Vienna (Austrian National Library, Codex 2527) and in Wolfenbüttel (Herzog-August-Bibliothek, Cod. Guelf. Gud. Lat. 69 2°). Gotthold Ephraim Lessing rediscovered the document when he worked as librarian in Wolfenbüttel, and published excerpts in 1774. The work contains perhaps the earliest reference to oil paint, which aroused great interest as the mention disproved Vasari's myth of Jan van Eyck developing the technique of oil painting in the early 15th century, about which antiquaries had already become suspicious. It also contains what seems to be the earliest textual evi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ibn Bassal
Ibn Bassal () was an 11th-century Andalusian Arab botanist and agronomist in Toledo and Seville, Spain who wrote about horticulture and arboriculture. He is best known for his book on agronomy, the ''Dīwān al-filāha'' (An Anthology of Husbandry). Life and work Ibn Bassal worked at the Abbasid court of Al-Mutamid, for whom he created the ''Hā’īṭ al-Sulṭān'' botanical garden in Seville. Originally from Toledo, Ibn Bassal moved to Seville after Alfonso VI conquered Toledo in 1085. He travelled (on pilgrimage) to the Hejaz, visiting Egypt, Sicily, Syria, and seemingly also countries from Abyssinia and Yemen to Iraq, Persia, and India. He returned with knowledge of the cultivation of cotton, and he may well have brought seeds and plants with him for the Toledo botanical garden. His book, Kitāb al-Kasd wa 'l-bayān' is primarily'' about horticulture. He is best known for his book on agronomy, the ''Dīwān al-filāha''. He also wrote the treatise ''The Classificat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Industrial Revolution
The Industrial Revolution, sometimes divided into the First Industrial Revolution and Second Industrial Revolution, was a transitional period of the global economy toward more widespread, efficient and stable manufacturing processes, succeeding the Second Agricultural Revolution. Beginning in Kingdom of Great Britain, Great Britain around 1760, the Industrial Revolution had spread to continental Europe and the United States by about 1840. This transition included going from craft production, hand production methods to machines; new Chemical industry, chemical manufacturing and Puddling (metallurgy), iron production processes; the increasing use of Hydropower, water power and Steam engine, steam power; the development of machine tools; and rise of the mechanisation, mechanised factory system. Output greatly increased, and the result was an unprecedented rise in population and population growth. The textile industry was the first to use modern production methods, and textiles b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Watt
James Watt (; 30 January 1736 (19 January 1736 OS) – 25 August 1819) was a Scottish inventor, mechanical engineer, and chemist who improved on Thomas Newcomen's 1712 Newcomen steam engine with his Watt steam engine in 1776, which was fundamental to the changes brought by the Industrial Revolution in both his native Great Britain and the rest of the world. While working as an instrument maker at the University of Glasgow, Watt became interested in the technology of steam engines. At the time engineers such as John Smeaton were aware of the inefficiencies of Newcomen's engine and aimed to improve it. Watt's insight was to realise that contemporary engine designs wasted a great deal of energy by repeatedly cooling and reheating the cylinder. Watt introduced a design enhancement, the separate condenser, which avoided this waste of energy and radically improved the power, efficiency, and cost-effectiveness of steam engines. Eventually, he adapted his engine to produce rot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
