Propellants and explosives for U.S Army Implementing Actodemil. Burning rate characteristics of GAP propellants Subscribe. Propellants, Explosives. High Energy Materials: Propellants, Explosives and. Posted on 30-Jul-2016 . High Energy Materials: Propellants, Explosives and Pyrotechnics pdf. Propellants and Explosives. Results: 1 – 20 of 639. ACS ActiveView PDF Hi-Res Print, Annotate, Reference QuickView; PDF ![]() An international journal full of PEP. PEP is the leading source for information on. Propellants; Explosives; Pyrotechnics; Ignition, combustion and detonation. Numerical Modeling of Explosives and Propellants, Third Edition. Numerical Modeling of Explosives and Propellants. Abstract - Download PDF (1.![]() Propellant - Wikipedia, the free encyclopedia. A propellant or propellent is a chemical substance used in the production of energy or pressurized gas that is subsequently used to create movement of a fluid or to generate propulsion of a vehicle, projectile, or other object. Common propellants are energetic materials and consist of a fuel like gasoline, jet fuel, rocket fuel, and an oxidizer. Propellants are burned or otherwise decomposed to produce the propellant gas. Other propellants are simply liquids that can readily be vaporized. In rockets and aircraft, propellants are used to produce a gas that can be directed through a nozzle, thereby producing thrust. In rockets, rocket propellant produces an exhaust, and the exhausted material is usually expelled under pressure through a nozzle. The pressure may be from a compressed gas, or a gas produced by a chemical reaction. The exhaust material may be a gas, liquid, plasma, or, before the chemical reaction, a solid, liquid, or gel. In aircraft, the propellant is usually a fuel and is combusted with the air. In firearm ballistics, propellants fill the interior of an ammunition cartridge or the chamber of a gun or cannon, leading to the expulsion of a bullet or shell (gunpowder, smokeless powder, and large gun propellants). Explosives can be placed in a sealed tube and act as a deflagrant low explosive charge in mining and demolition, to produce a low velocity heave effect (gas pressure blasting). Cold gas propellants may be used to fill an expansible bag or membrane, such as an automotive airbag (gas generator propellants) or in pressurised dispensing systems, such as aerosol sprays, to force a material through a nozzle. Examples of can propellants include nitrous oxide that is dissolved in canned whipped cream, and the dimethyl ether or low- boiling alkane used in hair spray. Rocket propellant may be expelled through an expansion nozzle as a cold gas, that is, without energetic mixing and combustion, to provide small changes in velocity to spacecraft by the use of cold gas thrusters. Aerosol sprays. As some gas escapes to expel the payload, more liquid evaporates, maintaining an even pressure. Propellant used for propulsion. For vehicles, the term propellant refers only to chemicals that are stored within the vehicle prior to use, and excludes atmospheric gas or other material that may be collected in operation. Among the English- speaking layperson, used to having fuels propel vehicles on Earth, the word fuel is inappropriately. In Germany, the word Treibstoff. The controlled burning of the propellant composition usually produces thrust by gaspressure and can accelerate a projectile, rocket, or other vehicle. In this sense, common or well- known propellants include, for firearms, artillery, and solid- propellant rockets: Gun propellants, such as. Composite propellants made from a solid oxidizer such as ammonium perchlorate or ammonium nitrate, a synthetic rubber such as HTPB, PBAN, or Polyurethane (or energetic polymers such as polyglycidyl nitrate or polyvinyl nitrate for extra energy), optional high- explosive fuels (again, for extra energy) such as RDX or nitroglycerin, and usually a powdered metalfuel such as aluminum. Some amateur propellants use potassium nitrate, combined with sugar, epoxy, or other fuels and binder compounds. Potassium perchlorate has been used as an oxidizer, paired with asphalt, epoxy, and other binders. Propellants that explode in operation are of little practical use currently, although there have been experiments with Pulse Detonation Engines. Also the newly synthesized bishomocubane based compounds are under consideration in the research stage as both solid and liquid propellants of the future. A grain is any individual particle of propellant regardless of the size or shape. The shape and size of a propellant grain determines the burn time, amount of gas, and rate produced from the burning propellant and, as a consequence, thrust vs time profile. There are three types of burns that can be achieved with different grains. Progressive Burn. Usually a grain with multiple perforations or a star cut in the center providing a lot of surface area. Degressive Burn. Usually a solid grain in the shape of a cylinder or sphere. Neutral Burn. Usually a single perforation; as outside surface decreases the inside surface increases at the same rate. Composition. Stabilizers and other additives are used to control the chemical stability and enhance the propellant. Stabilizers and other additives are also used. Nitroglycerin reduces smoke and increases the energy output. Double- based propellants are used in small arms, cannons, mortars and rockets. Triple- Based Propellant. Triple- based propellants consist of nitrocellulose, nitroguanidine, nitroglycerin or other liquid organic nitrate explosives. Triple- based propellants are used in cannons. Composite. Composites contain no nitrocellulose, nitroglycerin, nitroquanidine or any other organic nitrate. Composites usually consist of a fuel such as metallic aluminum, a combustible binder such as synthetic rubber or HTPB, and an oxidizer such as ammonium perchlorate. Composite propellants are used in large rocket motors. Liquid propellant. This gives high specific impulse and is ideal for high- velocity missionscryogenic oxygen- hydrocarbon propellant system - Used for many booster stages of space launch vehicles as well as a smaller number of second stages. This combination of fuel/oxidizer has high density and hence allows for a more compact booster design. They are instant- starting and suitable for long- term storage. Propellant combinations used for liquid propellant rockets include: Common monopropellant used for liquid rocket engines include: Hydrogen peroxide. Hydrazine. Red fuming nitric acid (RFNA)See also. Chemistry: An Asian Journal. Rocket Propulsion Elements. The most efficient fuel and oxidizer combination commonly used today for chemical liquid rockets is hydrogen (fuel) and oxygen (oxidizer). The two elements are relatively simple and they burn easily when combined. Refined petroleum is not the most efficient thrust- producing fuel for rockets, but what it lacks in thrust production it makes up for in density. It takes less volume of RP- 1 to impart the same thrust force on a vehicle, and less volume equates to reduced stage size. A smaller booster stage means much less aerodynamic drag as the vehicle lifts off from near sea- level and accelerates up through the more dense (thicker) part of the atmosphere near the earth. The result of a smaller booster stage is it allows a more efficient ascent through the thickest part of the atmosphere, which helps improve the net mass lifted to orbit.
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