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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.
A flaming cocktail works by burning ethanol (grain alcohol), a type of liquid fuel also found in all alcoholic drinks. Liquid fuels are combustible or energy-generating molecules that can be harnessed to create mechanical energy, usually producing kinetic energy; they also must take the shape of their container. It is the fumes of liquid fuels ...
Solid fuel rockets have lower specific impulse, a measure of propellant efficiency, than liquid fuel rockets. As a result, the overall performance of solid upper stages is less than liquid stages even though the solid mass ratios are usually in the .91 to .93 range, as good as or better than most liquid propellant upper stages.
Flashover occurs when the majority of the exposed surfaces in a space are heated to their autoignition temperature and emit flammable gases (see also flash point). Flashover normally occurs at 500 °C (932 °F) or 590 °C (1,100 °F) for ordinary combustibles and an incident heat flux at floor level of 20 kilowatts per square metre (2.5 hp/sq ft).
Cryogenic fuels are fuels that require storage at extremely low temperatures in order to maintain them in a liquid state. These fuels are used in machinery that operates in space (e.g. rockets and satellites) where ordinary fuel cannot be used, due to the very low temperatures often encountered in space, and the absence of an environment that supports combustion (on Earth, oxygen is abundant ...
Combustion of a liquid fuel in an oxidizing atmosphere actually happens in the gas phase. It is the vapor that burns, not the liquid. Therefore, a liquid will normally catch fire only above a certain temperature: its flash point. The flash point of liquid fuel is the lowest temperature at which it can form an ignitable mix with air.
The fuel is mixed with air within its flammable limits and heated by compression and subject to Boyle's law above its flash point, then ignited by the spark plug. To ignite, the fuel must have a low flash point, but in order to avoid preignition caused by residual heat in a hot combustion chamber, the fuel must have a high autoignition temperature.
The attendant wears a full hazmat suit due to the hazards of the hypergolic fuel hydrazine, here being loaded onto the MESSENGER space probe. A hypergolic propellant is a rocket propellant combination used in a rocket engine, whose components spontaneously ignite when they come into contact with each other.