العربية
中国
Français
Deutsch
Ελληνική
हिन्दी
Italiano
日本語
Português
Русский
EspañolHYPERGOLIC PROPELLANT
(Redirected from Hypergolic fuel)
A 'hypergolic propellant' is either of the two rocket propellants used in a hypergolic rocket engine, which spontaneously ignite when they come into contact. The two propellants are usually termed the "fuel" and the "oxidizer". Although hypergolic propellants are difficult to handle, a hypergolic engine is easy to control and very reliable.
During World War II, rocket propellants were broadly classed as monergols, hypergols and non-hypergols. The ending ''ergol'' is a combination of Greek ''ergon'' or work, and Latin ''oleum'' or oil, later influenced by the German chemical suffix ''-ol'' from alcohol.
A hypergolic engine can be precisely controlled with only two valves, one for each propellant. This simplifies the control system and eliminates points of failure. With no complex starting procedure the thrust is predictable, i.e., the direction and velocity of the rocket will closely match calculations.
Hypergolic propellants are also less likely to detonate when starting, a potentially catastrophic condition known as a hard start.
Hypergolic propellants have been used for intercontinental ballistic missiles, especially the Titan II, but because of difficulties in storing fuel, the trend in ICBMs has been to move toward solid-fuel boosters.
★ Hydrazine-nitric acid (toxic but stable)
★ Aniline-nitric acid (unstable, explosive)
★ Hydrogen peroxide-aniline (dust-sensitive, explosive)
★ UDMH-nitrogen tetroxide (by far the most common hypergolic fuel, less reactive than others, but by no means inert)
★ UDMH-IRFNA used in the MGM-52 Lance missile system (toxic and flammable but safe for long-term fueling of rockets)
★ MMH-nitrogen tetroxide used in the Space Shuttle program OMS and the EPS Upper Stage of the European Ariane 5 rocket
★ T-Stoff and C-Stoff used in the Messerschmitt Me 163 rocket fighter airplane
★ Hydrazine and nitrogen tetroxide used in the Lunar Module of the Apollo missions as well as the reaction control system (RCS) of the US Space Shuttle program
★ The Indian Space Research Organisation's PSLV rocket uses hypergolic propellants. Its stage 2 uses UDMH and N2O4, while its stage 4 uses MMH and MON as propellants.
★ "-ergol", ''Oxford English Dictionary''.
★ ''Modern Engineering for Design of Liquid-Propellant Rocket Engines'', Huzel & Huang, pub. AIAA, 1992. ISBN 1-56347-013-6.
★ ''History of Liquid Propellant Rocket Engines'', G. Sutton, pub. AIAA 2005. ISBN 1-56347-649-5.
A 'hypergolic propellant' is either of the two rocket propellants used in a hypergolic rocket engine, which spontaneously ignite when they come into contact. The two propellants are usually termed the "fuel" and the "oxidizer". Although hypergolic propellants are difficult to handle, a hypergolic engine is easy to control and very reliable.
| Contents |
| Derivation of the term |
| Advantages |
| Use in ICBMs |
| Common hypergolic propellants combinations |
| Sources |
Derivation of the term
During World War II, rocket propellants were broadly classed as monergols, hypergols and non-hypergols. The ending ''ergol'' is a combination of Greek ''ergon'' or work, and Latin ''oleum'' or oil, later influenced by the German chemical suffix ''-ol'' from alcohol.
Advantages
A hypergolic engine can be precisely controlled with only two valves, one for each propellant. This simplifies the control system and eliminates points of failure. With no complex starting procedure the thrust is predictable, i.e., the direction and velocity of the rocket will closely match calculations.
Hypergolic propellants are also less likely to detonate when starting, a potentially catastrophic condition known as a hard start.
Use in ICBMs
Hypergolic propellants have been used for intercontinental ballistic missiles, especially the Titan II, but because of difficulties in storing fuel, the trend in ICBMs has been to move toward solid-fuel boosters.
Common hypergolic propellants combinations
★ Hydrazine-nitric acid (toxic but stable)
★ Aniline-nitric acid (unstable, explosive)
★ Hydrogen peroxide-aniline (dust-sensitive, explosive)
★ UDMH-nitrogen tetroxide (by far the most common hypergolic fuel, less reactive than others, but by no means inert)
★ UDMH-IRFNA used in the MGM-52 Lance missile system (toxic and flammable but safe for long-term fueling of rockets)
★ MMH-nitrogen tetroxide used in the Space Shuttle program OMS and the EPS Upper Stage of the European Ariane 5 rocket
★ T-Stoff and C-Stoff used in the Messerschmitt Me 163 rocket fighter airplane
★ Hydrazine and nitrogen tetroxide used in the Lunar Module of the Apollo missions as well as the reaction control system (RCS) of the US Space Shuttle program
★ The Indian Space Research Organisation's PSLV rocket uses hypergolic propellants. Its stage 2 uses UDMH and N2O4, while its stage 4 uses MMH and MON as propellants.
Sources
★ "-ergol", ''Oxford English Dictionary''.
★ ''Modern Engineering for Design of Liquid-Propellant Rocket Engines'', Huzel & Huang, pub. AIAA, 1992. ISBN 1-56347-013-6.
★ ''History of Liquid Propellant Rocket Engines'', G. Sutton, pub. AIAA 2005. ISBN 1-56347-649-5.
This article provided by Wikipedia. To edit the contents of this article, click here for original source.
psst.. try this: add to faves
