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The liquid-rocket engine bipropellant liquid oxygen and hydrogen offers the highest specific impulse for conventional rockets. This extra performance largely offsets the disadvantage of low density, which requires larger fuel tanks.
Bipropellant liquid rockets use a liquid fuel such as liquid hydrogen or RP-1, and a liquid oxidizer such as liquid oxygen. The engine may be a cryogenic rocket engine , where the fuel and oxidizer, such as hydrogen and oxygen, are gases which have been liquefied at very low temperatures.
In the case of bipropellant liquid rockets, a mixture of reducing fuel and oxidizing oxidizer is introduced into a combustion chamber, typically using a turbopump to overcome the pressure. As combustion takes place, the liquid propellant mass is converted into a huge volume of gas at high temperature and pressure.
The Curie engine, named after Polish scientist Marie Skłodowska–Curie, is a small liquid-propellant rocket engine designed to release "small satellites from the constricting parameters of primary payload orbits and enables them to fully reach their potential, including faster deployment of small satellite constellations and better positioning for Earth imaging". [3]
Otto Fuel II, a mixture of the low explosive propylene glycol dinitrate with a stabilizer, has also been tried in 37mm guns. [2] In 1981, the Naval Weapons Center tried a 350 round/minute cyclic bipropellant gun, using 90% nitric acid and a proprietary hydrocarbon (probably a low molecular weight alkane, like propane). High or low breech ...
Monomethylhydrazine (MMH) is a highly toxic, volatile hydrazine derivative with the chemical formula CH 6 N 2.It is used as a rocket propellant in bipropellant rocket engines because it is hypergolic with various oxidizers such as nitrogen tetroxide (N 2 O 4) and nitric acid (HNO 3).
The most common hypergolic fuels, hydrazine, monomethylhydrazine and unsymmetrical dimethylhydrazine, and oxidizer, nitrogen tetroxide, are all liquid at ordinary temperatures and pressures. They are therefore sometimes called storable liquid propellants. They are suitable for use in spacecraft missions lasting many years.
Hybrid-propellant rockets use a combination of solid and liquid propellant, typically involving a liquid oxidizer being pumped through a hollow cylinder of solid fuel. All current spacecraft use conventional chemical rockets (solid-fuel or liquid bipropellant) for launch, though some [note 3] have used air-breathing engines on their first stage ...