Vulcain
Encyclopedia
Vulcain is a family of European
cryogenic first stage rocket engine
s for the Ariane 5
.
without being the cause of the disaster, and had its first successful flight in 1997 (flight 502). In 2002 the upgraded Vulcain 2 with 20% more thrust first flew on flight 517, although a problem with the engine turned the flight into a failure. The cause was due to flight loads being much higher than expected, as the inquiry board concluded. Subsequently, the nozzle has been redesigned, reinforcing the structure and improving the thermal situation of the tube wall, enhancing hydrogen coolant flow as well as applying thermal barrier coating to the flame-facing side of the coolant tubes, reducing heat load. The first successful flight of the (partially redesigned) Vulcain 2 occurred in 2005 on flight 521.
On 2007-06-17 Volvo Aero announced that in spring of 2008 it expected to hot-fire test a Vulcain 2 nozzle manufactured with a new "sandwich" technology.
The Vulcain engines are gas-generator cycle
cryogenic rocket engines fed with liquid oxygen
and liquid hydrogen
. They feature regenerative cooling through a tube wall design, and the Vulcain 2 introduced a particular film cooling for the lower part of the nozzle, where exhaust gas from the turbine is re-injected in the engine They power the first stage of the Ariane 5 launcher, the EPC (Étage Principal Cryotechnique, main cryogenic stage) and provide 8% of the total lift-off thrust (the rest being provided by the two solid rocket boosters). The engine operating time is 600 s in both configurations. 3 m tall and 1.76 m in diameter, the engine weighs 1686 kg and provides 137 t
of thrust in its latest version . The oxygen turbopump
rotates at 13600 rpm with a power of 3 MW while the hydrogen turbopump rotates at 34000 rpm with 12 MW of power. The total mass flow rate is 235 kg/s, of which 41.2 kg/s are of hydrogen.
(Sweden).
European Space Agency
The European Space Agency , established in 1975, is an intergovernmental organisation dedicated to the exploration of space, currently with 18 member states...
cryogenic first stage rocket engine
Rocket engine
A rocket engine, or simply "rocket", is a jet engineRocket Propulsion Elements; 7th edition- chapter 1 that uses only propellant mass for forming its high speed propulsive jet. Rocket engines are reaction engines and obtain thrust in accordance with Newton's third law...
s for the Ariane 5
Ariane 5
Ariane 5 is, as a part of Ariane rocket family, an expendable launch system used to deliver payloads into geostationary transfer orbit or low Earth orbit . Ariane 5 rockets are manufactured under the authority of the European Space Agency and the Centre National d'Etudes Spatiales...
.
History
The development of Vulcain, assured by a European collaboration, began in 1988 with the Ariane 5 rocket program. It first flew in 1996 powering the ill-fated flight 501Ariane 5 Flight 501
Cluster was a constellation of four European Space Agency spacecraft which were launched on the maiden flight of the Ariane 5 rocket, Flight 501, and subsequently lost when that rocket failed to achieve orbit. The launch, which took place on Tuesday, June 4, 1996, ended in failure due to an error...
without being the cause of the disaster, and had its first successful flight in 1997 (flight 502). In 2002 the upgraded Vulcain 2 with 20% more thrust first flew on flight 517, although a problem with the engine turned the flight into a failure. The cause was due to flight loads being much higher than expected, as the inquiry board concluded. Subsequently, the nozzle has been redesigned, reinforcing the structure and improving the thermal situation of the tube wall, enhancing hydrogen coolant flow as well as applying thermal barrier coating to the flame-facing side of the coolant tubes, reducing heat load. The first successful flight of the (partially redesigned) Vulcain 2 occurred in 2005 on flight 521.
Future development
Although different upgrades to the engine have been proposed, there is no current program to develop an uprated version of the engine. If there will ever be one, it is likely that the new engine would be introduced after the "PA batch" of 30 Ariane 5 ECAs ordered on 10 May 2004 will be expended.On 2007-06-17 Volvo Aero announced that in spring of 2008 it expected to hot-fire test a Vulcain 2 nozzle manufactured with a new "sandwich" technology.
Overview
| Vulcain | Vulcain 2 | |
| Vacuum thrust | 1120 kN | 1340 kN |
| Sea level thrust | 800 kN | 900 kN |
| Chamber pressure | 114 bar | 117 bar |
| Expansion ratio | 45:1 | 60:1 |
| Nominal specific impulse | 433 s | 431 s |
The Vulcain engines are gas-generator cycle
Gas-generator cycle (rocket)
The gas generator cycle is a power cycle of a bipropellant rocket engine. Some of the propellant is burned in a gas-generator and the resulting hot gas is used to power the engine's pumps. The gas is then exhausted...
cryogenic rocket engines fed with liquid oxygen
Liquid oxygen
Liquid oxygen — abbreviated LOx, LOX or Lox in the aerospace, submarine and gas industries — is one of the physical forms of elemental oxygen.-Physical properties:...
and liquid hydrogen
Liquid hydrogen
Liquid hydrogen is the liquid state of the element hydrogen. Hydrogen is found naturally in the molecular H2 form.To exist as a liquid, H2 must be pressurized above and cooled below hydrogen's Critical point. However, for hydrogen to be in a full liquid state without boiling off, it needs to be...
. They feature regenerative cooling through a tube wall design, and the Vulcain 2 introduced a particular film cooling for the lower part of the nozzle, where exhaust gas from the turbine is re-injected in the engine They power the first stage of the Ariane 5 launcher, the EPC (Étage Principal Cryotechnique, main cryogenic stage) and provide 8% of the total lift-off thrust (the rest being provided by the two solid rocket boosters). The engine operating time is 600 s in both configurations. 3 m tall and 1.76 m in diameter, the engine weighs 1686 kg and provides 137 t
Tonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...
of thrust in its latest version . The oxygen turbopump
Turbopump
A turbopump is a gas turbine that comprises basically two main components: a rotodynamic pump and a driving turbine, usually both mounted on the same shaft, or sometimes geared together...
rotates at 13600 rpm with a power of 3 MW while the hydrogen turbopump rotates at 34000 rpm with 12 MW of power. The total mass flow rate is 235 kg/s, of which 41.2 kg/s are of hydrogen.
Contractors
The main contractor for the Vulcain engines is Snecma Moteurs (France), which also provides the liquid hydrogen turbopump. The liquid oxygen turbopump is responsibility of Avio (Italy), the gas turbines that power the turbopumps and the nozzle are developed by VolvoVolvo
AB Volvo is a Swedish builder of commercial vehicles, including trucks, buses and construction equipment. Volvo also supplies marine and industrial drive systems, aerospace components and financial services...
(Sweden).
External links
- Arianespace - Ariane 5: Cryogenic Main Stage and Solid Boosters
- Ariane 5 ECA and Snecma - Snecma Moteurs: Vulcain 2 engine proves its mettle - Volvo Aero - Volvo Aero - Volvo Aero - Volvo Aero - Volvo Aero - Volvo Aero