Propellants hybrid

This system is very rarely used though it has certain advantages it has not found much favor with missile designers the world over. The use of hybrid propellants extends the range but poses additional engineering and combustion related problems. Figure 4.4 shows a simple hybrid rocket motor. 

Tam, W.H., Hersh, M., Ballinger, L, 2003. Hybrid propellant tanks for spacecraft and launch vehicles. In AIAA-2003-4607, 39th Joint Propulsion Conference, Huntsville, AL, July 20-23. 

Perhaps the best known oxide of nitrogen is N20, commonly called nitrous oxide or laughing gas. Nitrous oxide is frequently used as an anesthetic, particularly in dentistry. It is also the propellant gas used in whipped cream containers N20 is nontoxic, virtually tasteless, and quite soluble in vegetable oils. The N20 molecule, like all those in Figure 21.6, can be represented as a resonance hybrid. 

Only chemical propulsion will be further discussed, and in particular, that associated with liquid, solid, and hybrid motors and engines. These motors and engines are uniquely different from other chemical propulsion systems in that they carry on board the necessary propellants, as contrasted to jet engines that rely on atmospheric oxygen for combustion of the fuel. 

In a solid-propellant rocket motor, the propellant is contained within the wall of the combustion chamber, as shown in Fig. 1. This contrasts with liquid systems, where both the fuel and oxidizing components are stored in tanks external to the combustion chamber and are pumped or pressure-fed to the combustor. In hybrid systems, one component, usually the fuel, is contained in the combustion chamber, while the other component is fed to the chamber from a separate storage tank, as in liquid systems. The solid-propellant motor also has an ignition system located at one end to initiate operation of the rocket. The supersonic nozzle affects the conversion of... 

Rastogi, R. P. et al., Indian J. Chem., Sect. A, 1980, 19 A, 317-321 Reaction in this hybrid rocket propellant system is enhanced by presence of ammonium vanadate. 

Schmucker, PH. Hybrid-Raketenantriebe, Goldmann, Munchen 1972 James, R. Propellants and Explosives, Noyes Data Corporation, Park Ridge, New Jersey 1974... 

Series hybrids are electric cars with support from a small ICE, where only the electric motor propels the vehicle. There is no mechanical link between the combustion engine and the wheels. The ICE drives a generator that produces electricity that either flows to the electric motor that turns the wheels, or to a battery for storage. When the car is running solely on batteries, the engine turns on after the batteries have drained to a certain level and begins to recharge them. 

Though the pyrolants used in gas-hybrid rockets burn in a similar manner as rocket propellants, their chemical compositions are fuel-rich. The pyrolants burn incompletely and the combustion temperature is below about 1000 K. When an atomized oxidizer is mixed with the fuel-rich gas in the secondary combustor, the mixture reacts to generate high-temperature combustion products. The combushon performance designated by specific impulse, is dependent on the combinahon of pyrolant and oxidizer. 

WWII. Hybrid Rocket Propellants are described in this Vol... 

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 the initial stages, the end use of n-Al was largely dominated by defense-related applications. Small caliber primers for defense munitions, additives for solid and hybrid rocket propellants, enhanced lethality explosives and pyrotechnics and thermite-based weapons are some typical military applications of n-Al powder. The use of n-Al powder has also been reported for some civil applications such as fireworks, automotive inflators and airbag initiators as well as drilling and oil exploration. 

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