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Scramjets
A scramjet (supersonic combustion ramjet) is a variant of a ramjet airbreathing jet engine in which combustion takes place in supersonic airflow. As in ramjets, a scramjet relies on high vehicle speed to compress the incoming air forcefully before combustion (hence ''ram''jet), but whereas a ramjet decelerates the air to subsonic velocities before combustion using shock cones, a scramjet has no shock cone and slows the airflow using shockwaves produced by its ignition source in place of a shock cone. This allows the scramjet to operate efficiently at extremely high speeds. History Before 2000 The Bell X-1 attained supersonic flight in 1947 and, by the early 1960s, rapid progress toward faster aircraft suggested that operational aircraft would be flying at "hypersonic" speeds within a few years. Except for specialized rocket research vehicles like the North American X-15 and other rocket-powered spacecraft, aircraft top speeds have remained level, generally in the range of Ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scramjet Operation En
A scramjet (supersonic combustion ramjet) is a variant of a ramjet airbreathing jet engine in which combustion takes place in supersonic airflow. As in ramjets, a scramjet relies on high vehicle speed to compress the incoming air forcefully before combustion (hence ''ram''jet), but whereas a ramjet decelerates the air to subsonic velocities before combustion using shock cones, a scramjet has no shock cone and slows the airflow using shockwaves produced by its ignition source in place of a shock cone. This allows the scramjet to operate efficiently at extremely high speeds. History Before 2000 The Bell X-1 attained supersonic flight in 1947 and, by the early 1960s, rapid progress toward faster aircraft suggested that operational aircraft would be flying at "hypersonic" speeds within a few years. Except for specialized rocket research vehicles like the North American X-15 and other rocket-powered spacecraft, aircraft top speeds have remained level, generally in the range of M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Airbreathing Jet Engine
An airbreathing jet engine (or ''ducted jet engine'') is a jet engine that ejects a propelling (reaction) jet of hot exhaust gases after first taking in atmospheric air, followed by compression, heating and expansion back to atmospheric pressure through a nozzle. Alternatively the reaction jet may include a cold jet of ducted bypass air which has been compressed by a fan before returning to atmospheric pressure through an additional nozzle. These engines are gas turbine engines. Engines using only ram for the compression process, and no turbomachinery, are the ramjet and pulsejet. All practical airbreathing jet engines heat the air by burning fuel. Alternatively a heat exchanger may be used ( nuclear-powered jet engine). Most modern jet engines are turbofans. They replaced turbojets as they use less fuel. Background The original air-breathing gas turbine jet engine was the turbojet. It was a concept brought to life by two engineers, Frank Whittle in England UK and Hans von Oha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ramjet
A ramjet, or athodyd (aero thermodynamic duct), is a form of airbreathing jet engine that uses the forward motion of the engine to produce thrust. Since it produces no thrust when stationary (no ram air) ramjet-powered vehicles require an assisted take-off like a rocket assist to accelerate it to a speed where it begins to produce thrust. Ramjets work most efficiently at supersonic speeds around and can operate up to speeds of . Ramjets can be particularly useful in applications requiring a small and simple mechanism for high-speed use, such as missiles. The US, Canada, and UK had widespread ramjet powered missile defenses during the 1960s onward, such as the CIM-10 Bomarc and Bloodhound. Weapon designers are looking to use ramjet technology in artillery shells to give added range; a 120 mm mortar shell, if assisted by a ramjet, is thought to be able to attain a range of . They have also been used successfully, though not efficiently, as tip jets on the ends of helicopt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NASA X-43
The NASA X-43 was an experimental unmanned hypersonic aircraft with multiple planned scale variations meant to test various aspects of hypersonic flight. It was part of the X-plane series and specifically of NASA's Hyper-X program. It set several airspeed records for jet aircraft. The X-43 is the fastest jet-powered aircraft on record at approximately Mach 9.6.Thompson, Elvia, Keith Henry and Leslie Williams"Faster Than a Speeding Bullet: Guinness Recognizes NASA Scramjet."''NASA.'' Retrieved: August 1, 2011. A winged booster rocket with the X-43 placed on top, called a "stack", was drop launched from a Boeing B-52 Stratofortress. After the booster rocket (a modified first stage of the Pegasus rocket) brought the stack to the target speed and altitude, it was discarded, and the X-43 flew free using its own engine, a scramjet. The first plane in the series, the X-43A, was a single-use vehicle, of which three were built. The first X-43A was destroyed after malfunctioning in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyper-X
The NASA X-43 was an experimental unmanned hypersonic aircraft with multiple planned scale variations meant to test various aspects of hypersonic flight. It was part of the X-plane series and specifically of NASA's Hyper-X program. It set several airspeed records for jet aircraft. The X-43 is the fastest jet-powered aircraft on record at approximately Mach 9.6.Thompson, Elvia, Keith Henry and Leslie Williams"Faster Than a Speeding Bullet: Guinness Recognizes NASA Scramjet."''NASA.'' Retrieved: August 1, 2011. A winged booster rocket with the X-43 placed on top, called a "stack", was drop launched from a Boeing B-52 Stratofortress. After the booster rocket (a modified first stage of the Pegasus rocket) brought the stack to the target speed and altitude, it was discarded, and the X-43 flew free using its own engine, a scramjet. The first plane in the series, the X-43A, was a single-use vehicle, of which three were built. The first X-43A was destroyed after malfunctioning in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reed Business Information
RELX plc (pronounced "Rel-ex") is a British multinational information and analytics company headquartered in London, England. Its businesses provide scientific, technical and medical information and analytics; legal information and analytics; decision-making tools; and organise exhibitions. It operates in 40 countries and serves customers in over 180 nations. It was previously known as Reed Elsevier, and came into being in 1993 as a result of the merger of Reed International, a British trade book and magazine publisher, and Elsevier, a Netherlands-based scientific publisher. The company is publicly listed, with shares traded on the London Stock Exchange, Amsterdam Stock Exchange and New York Stock Exchange (ticker symbols: London: REL, Amsterdam: REN, New York: RELX). The company is one of the constituents of the FTSE 100 Index, Financial Times Global 500 and Euronext 100 Index. History The company, which was previously known as Reed Elsevier, came into being in 1993, as a r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Scientist
''New Scientist'' is a magazine covering all aspects of science and technology. Based in London, it publishes weekly English-language editions in the United Kingdom, the United States and Australia. An editorially separate organisation publishes a monthly Dutch-language edition. First published on 22 November 1956, ''New Scientist'' has been available in online form since 1996. Sold in retail outlets (paper edition) and on subscription (paper and/or online), the magazine covers news, features, reviews and commentary on science, technology and their implications. ''New Scientist'' also publishes speculative articles, ranging from the technical to the philosophical. ''New Scientist'' was acquired by Daily Mail and General Trust (DMGT) in March 2021. History Ownership The magazine was founded in 1956 by Tom Margerison, Max Raison and Nicholas Harrison as ''The New Scientist'', with Issue 1 on 22 November 1956, priced at one shilling (a twentieth of a pound in pre-decimal UK cu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DARPA
The Defense Advanced Research Projects Agency (DARPA) is a research and development agency of the United States Department of Defense responsible for the development of emerging technologies for use by the military. Originally known as the Advanced Research Projects Agency (ARPA), the agency was created on February 7, 1958, by President Dwight D. Eisenhower in response to the Soviet Union, Soviet launching of Sputnik 1 in 1957. By collaborating with academia, industry, and government partners, DARPA formulates and executes research and development projects to expand the frontiers of technology and science, often beyond immediate U.S. military requirements.Dwight D. Eisenhower and Science & Technology, (2008). Dwight D. Eisenhower Memorial CommissionSource ''The Economist'' has called DARPA the agency "that shaped the modern world," and pointed out that "Moderna COVID-19 vaccine, Moderna's COVID-19 vaccine sits alongside weather satellites, Global Positioning System, GPS, Unmann ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Capua
Capua ( , ) is a city and ''comune'' in the province of Caserta, in the region of Campania, southern Italy, situated north of Naples, on the northeastern edge of the Campanian plain. History Ancient era The name of Capua comes from the Etruscan ''Capeva''. The meaning is 'City of Marshes'. Its foundation is attributed by Cato the Elder to the Etruscans, and the date given as about 260 years before it was "taken" by Rome. If this is true it refers not to its capture in the Second Punic War (211 BC) but to its submission to Rome in 338 BC, placing the date of foundation at about 600 BC, while Etruscan power was at its highest. In the area several settlements of the Villanovian civilization were present in prehistoric times, and these were probably enlarged by the Oscans and subsequently by the Etruscans. Etruscan supremacy in Campania came to an end with the Samnite invasion in the latter half of the 5th century BC. About 424 BC it was captured by the Samnites and in 343 BC be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cassell Illustrated
Cassell & Co is a British book publishing house, founded in 1848 by John Cassell (1817–1865), which became in the 1890s an international publishing group company. In 1995, Cassell & Co acquired Pinter Publishers. In December 1998, Cassell & Co was bought by the Orion Publishing Group. In January 2002, Cassell imprints, including the Cassell Reference and Cassell Military were joined with the Weidenfeld imprints to form a new division under the name of Weidenfeld & Nicolson Ltd. Cassell Illustrated survives as an imprint of the Octopus Publishing Group. History John Cassell (1817–1865), who was in turn a carpenter, temperance preacher, tea and coffee merchant, finally turned to publishing. His first publication was on 1 July 1848, a weekly newspaper called ''The Standard of Freedom'' advocating religious, political, and commercial freedom. '' The Working Man's Friend'' became another popular publication. In 1849 Cassell was dividing his time between his publishing and his gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HyShot
HyShot is a research project of The University of Queensland, Australiabr>Centre for Hypersonics to demonstrate the possibility of supersonic combustion under flight conditions using two scramjet engines, one designed by The University of Queensland and one designed by QinetiQ (formerly the MOD's Defence Evaluation & Research Agency).Michael K. Smart, Neal E. Hass, and Allan Paull. "Flight Data Analysis of the HyShot 2 Scramjet Flight Experiment", AIAA Journal, Vol. 44, No. 10 (2006), pp. 2366-2375. Overview The project has involved the successful launch of one engine designed by The University of Queensland, and one launch of the scramjet designed by the British company QinetiQ. Each combustion unit was launched on the nose of a Terrier- Orion Mk70 sounding rocket on a high ballistic trajectory, reaching altitudes of approximately 330 km. The rocket was rotated to face the ground, and the combustion unit ignited for a period of 6–10 seconds while falling between 35&nbs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
