Rocket propellants liquid fuels

Nitromethane is active chemically, can have many chemical reactions as a chemical reagent or synthesis intermediate. It also can be used as solvents for cellulose nitrate, cellulose acetate, cellulose acetate, vinyl resin, polyacrylate coating, beeswax, etc. base or other materials can be added into nitromethane for generate explosives when nitromethane is mixed with strong oxidant hydrogen peroxide or N2O4, it can be used as liquid rocket propellants and fuel nitromethane can also be used in medicine, dyes, insecticides, fungicides, stabilizers and surfactants. 

Although modern chemistry allows development of even more effective rocket propellants, energy efficiency is not the only consideration factor. For example, fluorine and its derivatives arc better oxidizers than oxygen, but their extreme toxicity make them environmentally dangerous. The same concerns prevent the use of beryllium hydride—an excellent fuel that combines high density with the energy efficiency comparable to liquid hydrogen. 

The design of propellants for solid fuel rockets differs considerably from that for ordnance, because of the lower operating pressures, usually below 15 MPa. To understand the principles involved it is first necessary to give a brief account of rocket propulsion. In this account considerations will be restricted to motors based on solid propellants. Motors based on liquid fuels, such as petroleum fractions and liquid oxygen, depend on combustion processes of non-explosive type. 

Eluorine nitrate (FNO ) is a strong oxidizing gas or liquid. In the liquid state it explodes by shock or friction. It is used as an oxidizer for rocket propellant fuels. 

Ducted rockets are intermediate between solid rockets and liquid ramjets in their propulsion characteristics. The propulsive force of soHd rockets is generated by the combustion of propellants composed of oxidizer and fuel components. Thus, no additional fuels or oxidizers need to be introduced from the atmosphere into the rocket motor. The momentum change of the exhaust gas from the nozzle attached to the aft-end of the combustion chamber is converted into the thrust for propulsion. On the other hand, the propulsive force of Hquid ramjets is generated by the combustion of a liquid hydrocarbon fuel with air introduced from the atmo-sphere.Ii] jjjg incoming air is compressed by a shock wave formed at the air-intake attached to the front end of the combustor. The air taken in from the atmosphere serves only as the oxidizer for the ramjets. The thrust is created by the momentum difference between the exhaust gas from the combustor and the air taken in from the atmosphere. 

Hybrid Rocket Propellants. A special proplnt combination of unlike materials, particularly of unlike physical characteristics. Typical hybrid proplnt combinations are a solid fuel (or oxidizer) in combination with a liquid oxidizer (or fuel) in tjiat order. Sometimes a grain of solid fuel is encased in the combustion chamber of a rocket engine and burned in combination with liq oxygen. Similarly, a liq fuel may be injected into a combustion chamber in contact with a solid oxidizer. Another example is the use of concentrated hydrogen peroxide and a hydrocarbon fuel. In this case, the hydrogen peroxide is converted by decompn into a hot gas contg oxygen. The fuel is injected downstream of the first reaction, mixed with the hot oxidizer-rich gas, and burns (Ref 1)... 

In organizing the symposium, we made the usual division into solid and liquid rocket propellants. Most readers no doubt already know the relative merits of solid vs. liquid systems—viz., the instant readiness of solids (compared with cryogenic liquids), their higher density (important in volume-limited systems), and the relative simplicity of rocket construction liquids offer easy variation in thrust level and the attainment of higher specific impulses, the latter because physical separation permits the use of fuels and oxidizers that would be incompatible if premixed. 

Fundamental Combustion Research Relating to liquid Fuel Rocket Propellants... 

Thixotropic gels are also useful as propellants for rocket applications. These are commonly called thixotropes or gels. Normal fuels and oxidizers are converted into thioxotropes by the addition of a small quantity of a gelling agent in order to ensure uniform suspension of solid additives (usually metal additives) during storage. It is reported that if very finely pulverized particles of beryllium or aluminum are suspended in the liquid fuel, it is possible to increase the specific impulse substantially. 

It has been used as a solvent and as an intermediate in the manuf of chemicals used in the expl industry and of synthetic rubber (Ref 4). During WWII, acetal(as well as acetaldehyde) was used in Germany as hyper-gollic fuel in liquid rocket propellants in conjunction with red or white fuming nitric acid which served as an oxidizer. Acetal was later replaced by ca te ch o 1( Bren zc ate chin or Brenzol in Ger)(Ref 10)... 

Acetaldeiiyde(as well as acetal) was used during WVFII in Germany as a hypergolic(qvl) fuel in liquid rocket propellants in conjunction with oxidizers, red or white coned nitric acids. These fuels were later replaced by catechol(BrenzcatechoI or Brenzol, in Ger)... 

Amines have been used for the following purposes related to expls,propellants, pyrotechnic compositions and fuels a)Stabilizers for NC propellants(eg, diphenylaniinc, nitro-Jiphenylaniine and phenyl-/3-naphthylamine, the last examined in France(Ref 3) b)Sensi-tizers for some expl and propellent compns (Ref 4 and addnl ref d) c)Smoke-producing compds (Addnl Ref d) d)Liquid fuels for rockets in conjunction with strong oxidizers, such as nitric acid(some of these are hyper-golic) (Refs 6 8 and addnl refs e,g,i,k l) e)Additives to gasoline and other motor fuels (Addnl refs a,b,c f)... 

The Mechanism of Combustion of Solid Propellants in "Selected Combustion Problems-Fundamentals and Aeronautical Applications , AGARD Publication, Butterworths, London(1954) 22)S.S. Penner P.P.Datner, "Combustion Problems in Liquid-Fuel Rocket Engines , in 5th Symposium on Combustion, Reinhold, NY(1955), 11-28(A review with 84 refs) 22 a)Anon, "Military Explosives , TM 9-1910(1955), 229 31 22b)L. 

Thompson, D. M., U.S. Patent 6,210,504 Azidoalkyl-substituted Tertiary Amines as Fuel Components for Liquid- or Gel-based Rocket Propellants, Assigned 1999. 

In solid fuel rockets, the propellant container also serves as the combustion chamber in liquid fuel rockets it is the chamber in which the injected liquid components of the propellant are made to react with one another. The combustion chamber must withstand the predetermined working pressure and the temperatures developing at the chamber walls. In liquid fuel rockets the chamber wall is externally cooled in most cases in solid fuel rockets, in which internal charges... 

The moment at which emission of the gas jet by a rocket ends. In solid propellant rockets this moment corresponds to a complete burnout of the propellant in liquid fuel and hybrid rockets, reignition can take place. 

The propulsion assembly of a rocket or -> Missile. The driving force can be produced by burning liquid fuels in liquid oxidizers (liquid oxygen, nitric acid, or other oxidants such as liquid fluorine), by burning of solid propellants (-> Solid Propellant Rockets), by burning solid fuels in liquid oxidizers (-> Hybrids), or by catalytic decomposition of endothermal compounds (-> Hydrazine-, - Aerozim, - Aurol). 

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