RD-8

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

Template:Short description Script error: No such module "Infobox".Script error: No such module "Check for unknown parameters".

The RD-8 (Russian: Script error: No such module "Lang". and GRAU Index: 11D513) is a Soviet / Ukrainian liquid propellant rocket engine burning LOX and RG-1 (a rocket grade kerosene) in an oxidizer rich staged combustion cycle.[1][2] It has a four combustion chambers that provide thrust vector control by gimbaling each of the nozzles in a single axis ±33°.[3] It was designed in Dnipropetrovsk by the Yuzhnoye Design Bureau as the vernier thruster of the Zenit (GRAU: 11K77) second stage.[4] As such, it has always been paired with the RD-120 engine for main propulsion.[5][6]

It can only be started once, and as a high altitude engine it has a thrust of Script error: No such module "convert". and a specific impulse of Script error: No such module "convert"..[1][2] It is the first ever steering engine to use the staged combustion cycle, and as such is the basis for a family of planned engines for the Mayak launch vehicle family.[7]

The engine itself is built like a hollow cylinder, with a cylindrical space in the center so the RD-120 nozzle can pass through.[8]

Derivatives

Whilst Yuzhnoye's propulsion experience had been mostly on hypergolic propellants engines, like RD-855 or RD-861, they are considered too toxic for current ecological standards.[4][5] While Yuzhnoye still offer to develop hypergolic propulsion, such as RD-843 for the Vega's AVUM stage or the Tsyklon-4 project, Yuzhnoye selected a more environmentally friendly LOX and kerosene propellant for the Mayak launch vehicle family.[7]

Not only had Yuzhnoye mastered the most complex cycle for the propellant (oxidizer rich staged combustion cycle) with the RD-8, but they had worked closely with NPO Energomash during the RD-120 program. The manufacturing is done at its sister company of Yuzhmash in Dnipropetrovsk, and the RD-120 thrust augmentation project of 2001 to 2003 had been a mixed project between the three companies.[7]

On the base of this experience, a family of derivatives engines were proposed. While the RD-801 and RD-810 are really just based on the general technology, the other members of the family are related enough that they reuse many components of the RD-8.[7] One characteristic of this family is the limitation of keeping the preburner output temperature below Script error: No such module "convert"..[7]

  • RD-805 (or RD-802): A proposed upper stage engine of just Script error: No such module "convert". of thrust, it would use a single chamber of the RD-8.[9] While many new components would be required, it is considered a low technological risk since it only needs smaller versions of already developed component.[7]
  • RD-809 (sometimes identified as RD-809M): It is an RD-8 re arranged to minimize its diameter. It would use practically every single component of the RD-8, but arranged without the big hollow section in the middle. It was a proposed engine for a proposed liquid upper stage of the Antares rocket, then named Taurus II.[7] It would be capable of five engine burns in a single mission.[10]
  • RD-809K: A proposed single nozzle version of the RD-8. It would mix most principal elements of the RD-8 like the turbopumps with a main combustion chamber and nozzle adapted from the RD-861K.[7][11] It would be capable of 4 starts in a single mission.[11] It is expected to be used in a dual engine configuration in the Mayak upper stage.[7]

See also

  • RD-120 – The Zenit second stage main engine which is the companion of the RD-8 and the basis for some of its derivatives.
  • Zenit – The launch vehicle family for which the RD-8 was developed.
  • Mayak – Prospective Ukrainian launch vehicle family for which the RD-805, RD-809 and RD-809K are being developed.
  • Yuzhnoe Design Bureau - The RD-8 designer bureau.
  • Yuzhmash - A multi-product machine-building company that's closely related to Yuzhnoe and manufactures the RD-8.

References

<templatestyles src="Reflist/styles.css" />

  1. a b Script error: No such module "citation/CS1".
  2. a b Script error: No such module "citation/CS1".
  3. Script error: No such module "citation/CS1".Script error: No such module "Unsubst".
  4. a b Script error: No such module "citation/CS1".
  5. a b Script error: No such module "citation/CS1".
  6. Script error: No such module "citation/CS1".
  7. a b c d e f g h i Script error: No such module "Citation/CS1".
  8. Script error: No such module "citation/CS1".
  9. Script error: No such module "citation/CS1".
  10. Script error: No such module "citation/CS1".
  11. a b Script error: No such module "citation/CS1".
Cite error: Script error: No such module "Namespace detect".Script error: No such module "Namespace detect".

Script error: No such module "Check for unknown parameters".

External links

Template:Rocket engines Script error: No such module "Navbox".