liquid propellant
Quick Summary
Liquid propellants are substances used in rocket engines that undergo rapid combustion to produce expanding gases, which then generate thrust. Unlike solid propellants, liquid propellants are stored in tanks separate from the combustion chamber. These systems typically use a liquid oxidizer and a liquid fuel, pumped into the chamber where they mix and ignite.
Key advantages of liquid-propellant engines include higher attainable exhaust velocities, better control over thrust (throttleability), and the ability to stop and restart. This makes them suitable for various applications, including upper stages of rockets and first-stage launch vehicles. Common oxidizers include liquid oxygen, while fuels can range from liquid hydrogen to hydrocarbons like kerosene. Some liquid propellants are cryogenic, requiring extremely low temperatures for storage.1
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Solid and liquid propellants are substances that undergo rapid combustion, producing gaseous products. Black powder was used as a propellant in guns and rockets until the 20th century, when double-base gunpowder (40 percent nitroglycerin, 60 percent nitrocellulose) came into use. Other modern solid propellants are cast perchlorate…
Read MoreSolid and liquid propellants are substances that undergo rapid combustion, producing gaseous products. Black powder was used as a propellant in guns and rockets until the 20th century, when double-base gunpowder (40 percent nitroglycerin, 60 percent nitrocellulose) came into use. Other modern solid propellants are cast perchlorate…
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rocketLiquid-propellant rocket enginesLiquid-propellant systems carry the propellant in tanks external to the combustion chamber. Most of these engines use a liquid oxidizer and a liquid fuel, which are transferred from their respective tanks by pumps. The pumps raise the pressure above the operating pressure of the engine,…
Read MoreLiquid-propellant systems carry the propellant in tanks external to the combustion chamber. Most of these engines use a liquid oxidizer and a liquid fuel, which are transferred from their respective tanks by pumps. The pumps raise the pressure above the operating pressure of the engine,…
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rocket and missile systemFrom liquid to solid fuelThis first generation of missiles was typified by its liquid fuel, which required both a propellant and an oxidizer for ignition as well as a complex (and heavy) system of pumps. The early liquid fuels were quite dangerous, difficult to store,…
Read MoreThis first generation of missiles was typified by its liquid fuel, which required both a propellant and an oxidizer for ignition as well as a complex (and heavy) system of pumps. The early liquid fuels were quite dangerous, difficult to store,…
Read More