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Bipropellant
The highest specific impulse chemical rockets use liquid propellants (liquid-propellant rockets). They can consist of a single chemical (a monopropellant) or a mix of two chemicals, called bipropellants. Bipropellants can further be divided into two categories; hypergolic propellants, which ignite when the fuel and oxidizer make contact, and non-hypergolic propellants which require an ignition source. About 170 different propellants made of liquid fuel have been tested, excluding minor changes to a specific propellant such as propellant additives, corrosion inhibitors, or stabilizers. In the U.S. alone at least 25 different propellant combinations have been flown. As of 2020, no completely new propellant has been used since the mid-1970s. Many factors go into choosing a propellant for a liquid-propellant rocket engine. The primary factors include ease of operation, cost, hazards/environment and performance. History Development in early 20th century Konstantin Tsiolkovsky pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liquid-propellant Rocket
A liquid-propellant rocket or liquid rocket utilizes a rocket engine that uses liquid propellants. Liquids are desirable because they have a reasonably high density and high specific impulse (''I''sp). This allows the volume of the propellant tanks to be relatively low. It is also possible to use lightweight centrifugal turbopumps to pump the rocket propellant from the tanks into the combustion chamber, which means that the propellants can be kept under low pressure. This permits the use of low-mass propellant tanks that do not need to resist the high pressures needed to store significant amounts of gasses, resulting in a low mass ratio for the rocket. An inert gas stored in a tank at a high pressure is sometimes used instead of pumps in simpler small engines to force the propellants into the combustion chamber. These engines may have a higher mass ratio, but are usually more reliable, and are therefore used widely in satellites for orbit maintenance. Liquid rockets can be m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bipropellants
A liquid-propellant rocket or liquid rocket utilizes a rocket engine that uses liquid propellants. Liquids are desirable because they have a reasonably high density and high specific impulse (''I''sp). This allows the volume of the propellant tanks to be relatively low. It is also possible to use lightweight centrifugal turbopumps to pump the rocket propellant from the tanks into the combustion chamber, which means that the propellants can be kept under low pressure. This permits the use of low-mass propellant tanks that do not need to resist the high pressures needed to store significant amounts of gasses, resulting in a low mass ratio for the rocket. An inert gas stored in a tank at a high pressure is sometimes used instead of pumps in simpler small engines to force the propellants into the combustion chamber. These engines may have a higher mass ratio, but are usually more reliable, and are therefore used widely in satellites for orbit maintenance. Liquid rockets can be mono ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypergolic Propellant
A hypergolic propellant is a rocket propellant combination used in a rocket engine, whose components spontaneously ignite when they come into contact with each other. The two propellant components usually consist of a fuel and an oxidizer. The main advantages of hypergolic propellants are that they can be stored as liquids at room temperature and that engines which are powered by them are easy to ignite reliably and repeatedly. Common hypergolic propellants are difficult to handle due to their extreme toxicity and/or corrosiveness. In contemporary usage, the terms "hypergol" and "hypergolic propellant" usually mean the most common such propellant combination: dinitrogen tetroxide plus hydrazine and/or its relatives monomethylhydrazine (MMH) and unsymmetrical dimethylhydrazine (UDMH). History In 1935, Hellmuth Walter discovered that hydrazine hydrate was hypergolic with high-test peroxide of 80-83%. He was probably the first to discover this phenomenon, and set to work ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypergolic Propellant
A hypergolic propellant is a rocket propellant combination used in a rocket engine, whose components spontaneously ignite when they come into contact with each other. The two propellant components usually consist of a fuel and an oxidizer. The main advantages of hypergolic propellants are that they can be stored as liquids at room temperature and that engines which are powered by them are easy to ignite reliably and repeatedly. Common hypergolic propellants are difficult to handle due to their extreme toxicity and/or corrosiveness. In contemporary usage, the terms "hypergol" and "hypergolic propellant" usually mean the most common such propellant combination: dinitrogen tetroxide plus hydrazine and/or its relatives monomethylhydrazine (MMH) and unsymmetrical dimethylhydrazine (UDMH). History In 1935, Hellmuth Walter discovered that hydrazine hydrate was hypergolic with high-test peroxide of 80-83%. He was probably the first to discover this phenomenon, and set to work ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kummersdorf
Kummersdorf is the name of an estate near Luckenwalde, around 25 km south of Berlin, in the Brandenburg region of Germany. Until 1945 Kummersdorf hosted the weapon office of the German Army which ran a development centre for future weapons as well as an artillery range. Early history In 1871, the Prussian ministry of war decided to move the artillery test range at Tegel to the Kummersdorf Forest. The new range became operational on 15 October 1875 when it was connected with the Royal Prussian Military Railway. In 1880, the first firing experiments took place on the 12 km southeast-northwest firing range. These experiments investigated the effectiveness of various fortifications, and the effects of weapons and projectiles. Total size of the Kummersdorf Firing Range was 878.1 hectares. In 1913, the dropping of bombs from the LZ 13 Hansa airship and Wright biplanes was investigated. In the 1920s, secret development started in the areas of artillery, armored forces, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frank H
Frank or Franks may refer to: People * Frank (given name) * Frank (surname) * Franks (surname) * Franks, a medieval Germanic people * Frank, a term in the Muslim world for all western Europeans, particularly during the Crusades - see Farang Currency * Liechtenstein franc or frank, the currency of Liechtenstein since 1920 * Swiss franc or frank, the currency of Switzerland since 1850 * Westphalian frank, currency of the Kingdom of Westphalia between 1808 and 1813 * The currencies of the German-speaking cantons of Switzerland (1803–1814): ** Appenzell frank ** Argovia frank ** Basel frank ** Berne frank ** Fribourg frank ** Glarus frank ** Graubünden frank ** Luzern frank ** Schaffhausen frank ** Schwyz frank ** Solothurn frank ** St. Gallen frank ** Thurgau frank ** Unterwalden frank ** Uri frank ** Zürich frank Places * Frank, Alberta, Canada, an urban community, formerly a village * Franks, Illinois, United States, an unincorporated community * Franks, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fritz Von Opel
Fritz Adam Hermann von Opel (4 May 1899 – 8 April 1971) was a German rocket technology pioneer and automotive executive, nicknamed "Rocket-Fritz". He is remembered mostly for his spectacular demonstrations of rocket propulsion that earned him an important place in the history of aviation and spaceflight as head of the world's first large-scale rocket program, Opel-RAK. Fritz von Opel, known as Fritz Adam Hermann Opel until his father was ennobled in 1917, was the only son of Wilhelm von Opel and a grandson of Adam Opel, founder of the Opel company. Life and career Opel was born in Rüsselsheim. He studied at the Technische Universität Darmstadt and received his doctorate from the university. After graduation, he was made director of testing for the Opel company and also put in charge of publicity. Fritz von Opel was a grandson of Adam Opel and son of Wilhelm von Opel. His sister was Elinor von Opel, a cousin Georg von Opel. When his father Wilhelm was raised to hereditary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heereswaffenamt
''Waffenamt'' (WaA) was the German Army Weapons Agency. It was the centre for research and development of the Weimar Republic and later the Third Reich for weapons, ammunition and army equipment to the German Reichswehr and then Wehrmacht The ''Wehrmacht'' (, ) were the unified armed forces of Nazi Germany from 1935 to 1945. It consisted of the ''Heer'' (army), the ''Kriegsmarine'' (navy) and the ''Luftwaffe'' (air force). The designation "''Wehrmacht''" replaced the previou .... It was founded 8 November 1919 as ''Reichwaffenamt'' (RWA), and 5 May 1922 the name was changed to ''Heereswaffenamt'' (HWA). The task of overseeing Germany's gigantic pre-World War II rearmament program was given to the ''Heeresabnahmestelle'' (the Army Acceptance Organization, commonly referred to as the ''Abnahme''), a subsidiary of the ''Heereswaffenamt''. By 1940 the ''Abnahme'' consisted of 25,000 personnel in five departments in 16 inspection areas, augmented by specially selected plan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Walter Dornberger
Major-General Dr. Walter Robert Dornberger (6 September 1895 – 26 June 1980) was a German Army artillery officer whose career spanned World War I and World War II. He was a leader of Nazi Germany's V-2 rocket programme and other projects at the Peenemünde Army Research Centre. Dornberger was born in Gießen and enlisted in 1914. In October 1918, as an artillery lieutenant Dornberger was captured by United States Marines and spent two years in a French prisoner of war camp, mostly in solitary confinement because of repeated escape attempts. In the late 1920s, Dornberger completed an engineering course with distinction at the Berlin Technical Institute, and in the Spring of 1930,Dornberger's detailed account of the V2 project was one of the first to be published by a major participant. Dornberger graduated after five years with an MS degree in mechanical engineering from the '' Technische Hochschule Charlottenburg'' in Berlin. In 1935, Dornberger received an honorary d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Specific Impulse
Specific impulse (usually abbreviated ) is a measure of how efficiently a reaction mass engine (a rocket using propellant or a jet engine using fuel) creates thrust. For engines whose reaction mass is only the fuel they carry, specific impulse is exactly proportional to the effective exhaust gas velocity. A propulsion system with a higher specific impulse uses the mass of the propellant more efficiently. In the case of a rocket, this means less propellant needed for a given delta-v, so that the vehicle attached to the engine can more efficiently gain altitude and velocity. In an atmospheric context, specific impulse can include the contribution to impulse provided by the mass of external air that is accelerated by the engine in some way, such as by an internal turbofan or heating by fuel combustion participation then thrust expansion or by external propeller. Jet engines breathe external air for both combustion and by-pass, and therefore have a much higher specific impulse than ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Verein Für Raumschiffahrt
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''Verein'' is a German word, sometimes translated as ''union'', ''club'' or ''association'', and may refer to: * ''Eingetragener Verein'' (e. V.), a registered voluntary association under German law * Swiss Verein, a voluntary association under Swiss law, not necessarily registered See also * Association (other) * Verein für Socialpolitik, a society of economists in the German-speaking area * Voluntary association A voluntary group or union (also sometimes called a voluntary organization, common-interest association, association, or society) is a group of individuals who enter into an agreement, usually as volunteers, to form a body (or organization) to a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wernher Von Braun
Wernher Magnus Maximilian Freiherr von Braun ( , ; 23 March 191216 June 1977) was a German and American aerospace engineer and space architect. He was a member of the Nazi Party and Allgemeine SS, as well as the leading figure in the development of rocket technology in Nazi Germany and later a pioneer of rocket and space technology in the United States. As a young man, von Braun worked in Nazi Germany's rocket development program. He helped design and co-developed the V-2 rocket at Peenemünde during World War II. Following the war, he was secretly moved to the United States, along with about 1,600 other German scientists, engineers, and technicians, as part of Operation Paperclip. He worked for the United States Army on an intermediate-range ballistic missile program, and he developed the rockets that launched the United States' first space satellite Explorer 1 in 1958. He worked with Walt Disney on a series of films, which popularized the idea of human space travel in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
