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Impulse Facility
An impulse facility is a testing facility that relies on rapid release of stored energy to generate a short period of high enthalpy test conditions for testing of aerodynamic flow, aerodynamic heating and atmospheric reentry, combustion, chemical kinetics, ballistics, and other effects. The rapid release of energy can result in very high instantaneous energy release rates even though the total energy released is modest. The use of an impulse facility can allow testing of violently energetic phenomena generating temperatures and pressures that no known materials could withstand in steady state. This effect also produces short test times, however, with some types of tests in these facilities lasting less than 100 microseconds. Impulse facilities are a special case of blow down facilities where an energy storage mechanism is charged over a period of time and then released to initiate a test and must be charged again before the next test. This contrasts with continuous facilities ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Energy
In physics, energy (from Ancient Greek: ἐνέργεια, ''enérgeia'', “activity”) is the quantitative property that is transferred to a body or to a physical system, recognizable in the performance of work and in the form of heat and light. Energy is a conserved quantity—the law of conservation of energy states that energy can be converted in form, but not created or destroyed. The unit of measurement for energy in the International System of Units (SI) is the joule (J). Common forms of energy include the kinetic energy of a moving object, the potential energy stored by an object (for instance due to its position in a field), the elastic energy stored in a solid object, chemical energy associated with chemical reactions, the radiant energy carried by electromagnetic radiation, and the internal energy contained within a thermodynamic system. All living organisms constantly take in and release energy. Due to mass–energy equivalence, any object that has mass whe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enthalpy
Enthalpy , a property of a thermodynamic system, is the sum of the system's internal energy and the product of its pressure and volume. It is a state function used in many measurements in chemical, biological, and physical systems at a constant pressure, which is conveniently provided by the large ambient atmosphere. The pressure–volume term expresses the work required to establish the system's physical dimensions, i.e. to make room for it by displacing its surroundings. The pressure-volume term is very small for solids and liquids at common conditions, and fairly small for gases. Therefore, enthalpy is a stand-in for energy in chemical systems; bond, lattice, solvation and other "energies" in chemistry are actually enthalpy differences. As a state function, enthalpy depends only on the final configuration of internal energy, pressure, and volume, not on the path taken to achieve it. In the International System of Units (SI), the unit of measurement for enthalpy is the joule. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aerodynamic
Aerodynamics, from grc, ἀήρ ''aero'' (air) + grc, δυναμική (dynamics), is the study of the motion of air, particularly when affected by a solid object, such as an airplane wing. It involves topics covered in the field of fluid dynamics and its subfield of gas dynamics. The term ''aerodynamics'' is often used synonymously with gas dynamics, the difference being that "gas dynamics" applies to the study of the motion of all gases, and is not limited to air. The formal study of aerodynamics began in the modern sense in the eighteenth century, although observations of fundamental concepts such as aerodynamic drag were recorded much earlier. Most of the early efforts in aerodynamics were directed toward achieving heavier-than-air flight, which was first demonstrated by Otto Lilienthal in 1891. Since then, the use of aerodynamics through mathematical analysis, empirical approximations, wind tunnel experimentation, and computer simulations has formed a rational basis for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atmospheric Reentry
Atmospheric entry is the movement of an object from outer space into and through the gases of an atmosphere of a planet, dwarf planet, or natural satellite. There are two main types of atmospheric entry: ''uncontrolled entry'', such as the entry of astronomical objects, space debris, or bolides; and ''controlled entry'' (or ''reentry'') of a spacecraft capable of being navigated or following a predetermined course. Technologies and procedures allowing the controlled atmospheric ''entry, descent, and landing'' of spacecraft are collectively termed as ''EDL''. Objects entering an atmosphere experience atmospheric drag, which puts mechanical stress on the object, and aerodynamic heating—caused mostly by compression of the air in front of the object, but also by drag. These forces can cause loss of mass (ablation) or even complete disintegration of smaller objects, and objects with lower compressive strength can explode. Crewed space vehicles must be slowed to subsonic speeds be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Combustion
Combustion, or burning, is a high-temperature exothermic redox chemical reaction between a fuel (the reductant) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. Combustion does not always result in fire, because a flame is only visible when substances undergoing combustion vaporize, but when it does, a flame is a characteristic indicator of the reaction. While the activation energy must be overcome to initiate combustion (e.g., using a lit match to light a fire), the heat from a flame may provide enough energy to make the reaction self-sustaining. Combustion is often a complicated sequence of elementary radical reactions. Solid fuels, such as wood and coal, first undergo endothermic pyrolysis to produce gaseous fuels whose combustion then supplies the heat required to produce more of them. Combustion is often hot enough that incandescent light in the form of either glowing or a flame is produced. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Kinetics
Chemical kinetics, also known as reaction kinetics, is the branch of physical chemistry that is concerned with understanding the rates of chemical reactions. It is to be contrasted with chemical thermodynamics, which deals with the direction in which a reaction occurs but in itself tells nothing about its rate. Chemical kinetics includes investigations of how experimental conditions influence the speed of a chemical reaction and yield information about the reaction's mechanism and transition states, as well as the construction of mathematical models that also can describe the characteristics of a chemical reaction. History In 1864, Peter Waage and Cato Guldberg pioneered the development of chemical kinetics by formulating the law of mass action, which states that the speed of a chemical reaction is proportional to the quantity of the reacting substances.C.M. Guldberg and P. Waage,"Studies Concerning Affinity" ''Forhandlinger i Videnskabs-Selskabet i Christiania'' (1864), 35P. W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ballistics
Ballistics is the field of mechanics concerned with the launching, flight behaviour and impact effects of projectiles, especially ranged weapon munitions such as bullets, unguided bombs, rockets or the like; the science or art of designing and accelerating projectiles so as to achieve a desired performance. A ballistic body is a free-moving body with momentum which can be subject to forces such as the forces exerted by pressurized gases from a gun barrel or a propelling nozzle, normal force by rifling, and gravity and air drag during flight. A ballistic missile is a missile that is guided only during the relatively brief initial phase of powered flight and the trajectory is subsequently governed by the laws of classical mechanics; in contrast to (for example) a cruise missile which is aerodynamically guided in powered flight like a fixed-wing aircraft. History and prehistory The earliest known ballistic projectiles were stones and spears, and the throwing stick. The oldes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microsecond
A microsecond is a unit of time in the International System of Units (SI) equal to one millionth (0.000001 or 10−6 or ) of a second. Its symbol is μs, sometimes simplified to us when Unicode is not available. A microsecond is equal to 1000 nanoseconds or of a millisecond. Because the next SI prefix is 1000 times larger, measurements of 10−5 and 10−4 seconds are typically expressed as tens or hundreds of microseconds. Examples * 1 microsecond (1 μs) – cycle time for frequency (1 MHz), the inverse unit. This corresponds to radio wavelength 300 m (AM medium wave band), as can be calculated by multiplying 1 μs by the speed of light (approximately ). * 1 microsecond – the length of time of a high-speed, commercial strobe light flash (see air-gap flash). * 1 microsecond – protein folding takes place on the order of microseconds. * 1.8 microseconds – the amount of time subtracted from the Earth's day as a result of the 2011 Japanese earthquake. * 2 m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blow Down Facility
Blow commonly refers to: * Cocaine * Exhalation *Strike (attack) Blow, Blew, Blowing, or Blown may also refer to: People * Blew (surname) *Blow (surname) Arts and entertainment Music * The Blow, an American electro-pop band Albums * ''Blow'' (Foetus album), 2001 * ''Blow'' (Ghinzu album) or the title song, 2004 * ''Blow'' (Heather Nova album), 1993 * ''Blow'' (Messy Marv and Berner album), 2009 **'' Blow: Blocks and Boat Docks'' or the title song, by Messy Marv and Berner, 2010 * ''Blow'' (Red Lorry Yellow Lorry album) or the title song, 1989 * ''Blow'' (Straitjacket Fits album), 1993 Songs *" Blew", by Nirvana, 1989 * "Blow" (Beyoncé song), 2013 * "Blow" (Ed Sheeran, Chris Stapleton and Bruno Mars song), 2019 * "Blow" (Kesha song), 2011 * "Blow" (Martin Solveig song), 2014 *"B.L.O.W.", by Tory Lanez, 2015 *"Blow", by Ashnikko, 2018 *"Blow", by Atreyu from ''Lead Sails Paper Anchor'', 2007 *"Blow", by the Prom Kings from ''The Prom Kings'', 2005 *"Blow", by Rick Ross fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Continuous Facility
Continuity or continuous may refer to: Mathematics * Continuity (mathematics), the opposing concept to discreteness; common examples include ** Continuous probability distribution or random variable in probability and statistics ** Continuous game, a generalization of games used in game theory ** Law of Continuity, a heuristic principle of Gottfried Leibniz * Continuous function, in particular: ** Continuity (topology), a generalization to functions between topological spaces ** Scott continuity, for functions between posets ** Continuity (set theory), for functions between ordinals ** Continuity (category theory), for functors ** Graph continuity, for payoff functions in game theory * Continuity theorem may refer to one of two results: ** Lévy's continuity theorem, on random variables ** Kolmogorov continuity theorem, on stochastic processes * In geometry: ** Parametric continuity, for parametrised curves ** Geometric continuity, a concept primarily applied to the conic s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wind Tunnel
Wind tunnels are large tubes with air blowing through them which are used to replicate the interaction between air and an object flying through the air or moving along the ground. Researchers use wind tunnels to learn more about how an aircraft will fly. NASA uses wind tunnels to test scale models of aircraft and spacecraft. Some wind tunnels are large enough to contain full-size versions of vehicles. The wind tunnel moves air around an object, making it seem as if the object is flying. Most of the time, large powerful fans suck air through the tube. The object being tested is held securely inside the tunnel so that it remains stationary. The object can be an aerodynamic test object such as a cylinder or an airfoil, an individual component, a small model of the vehicle, or a full-sized vehicle. The air moving around the stationary object shows what would happen if the object was moving through the air. The motion of the air can be studied in different ways; smoke or dye can be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shock Tube
: ''For the pyrotechnic initiator, see Shock tube detonator'' The shock tube is an instrument used to replicate and direct blast waves at a sensor or a model in order to simulate actual explosions and their effects, usually on a smaller scale. Shock tubes (and related impulse facilities such as shock tunnels, expansion tubes, and expansion tunnels) can also be used to study aerodynamic flow under a wide range of temperatures and pressures that are difficult to obtain in other types of testing facilities. Shock tubes are also used to investigate compressible flow phenomena and gas phase combustion reactions. More recently, shock tubes have been used in biomedical research to study how biological specimens are affected by blast waves. A shock wave inside a shock tube may be generated by a small explosion (blast-driven) or by the buildup of high pressures which cause diaphragm(s) to burst and a shock wave to propagate down the shock tube (compressed-gas driven). History An earl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
