RD-0120
The RD-0120 (from Russian Реактивный двигатель , "Reaktiwnyj Dwigatel", German rocket engine, GRAU index 11D122, internal designation RO-200) is a rocket engine for liquid rockets . It should not be confused with the RD-120 (11D123) of the Zenit rocket , which achieves a much lower thrust.
Development and use
The RD-0120 was developed by the Soviet rocket engine designer Semjon Kosberg between 1976 and 1990 at the Chemical Automatics Design Bureau and is now distributed by RKZ Progress . The engine served as a drive for the central stage (second stage) of the Energija rocket, which is powered by four of the RD-0120 engines, each equipped with a combustion chamber. The first tests with full thrust took place in May 1984, the first flight in May 1987 and the last use in 1988. Later variants with methane instead of hydrogen as fuel (RD-0120-CH) and further developed variants (RD-0120M and RD- 0122).
technology
Like the main engines (SSME) of the space shuttle, the RD-0120 is operated with liquid hydrogen and oxygen (LH2 / LOX), which was a novelty for Soviet space travel at the time. It can be regulated down to 55% of its full capacity. There are backing pumps that are operated hydraulically (oxygen) or with the energy from the combustion chamber cooling (hydrogen). The main pumps for fuel and oxidizer , as well as a two-stage turbine, are located on a single, common shaft. The energy to drive the turbine comes from a single pre-combustion chamber in which the majority of the hydrogen is pre-burned with a small part of the oxygen at a lower temperature before it is fed to the main combustion chamber. As with the SSME, the RD-0120 uses a main flow process with fuel-rich staged combustion (FRSC), whereas the SSME uses a more complex design with two shafts and two pre-combustion chambers for the main oxidizer pump and the main hydrogen pump. The design as a main flow engine is absolutely necessary for the high combustion chamber pressures sought, as this is the only way, in contrast to the bypass flow method (gas generator cycle), that no fuel is lost through the tapping in the gas generator for the main combustion chamber.
Technical specifications
| RD-0120 | |
|---|---|
| Mixing ratio LOX / LH2 | 6.0 |
| Total height | 4.55 m |
| diameter | 2.42 m |
| Dry matter | 3450 kg |
| Thrust / weight ratio (floor / vacuum) | 44/58 |
| Combustion chamber diameter | 261 mm |
| Nozzle end diameter | 2420 mm |
| Combustion chamber pressure | 218 bar |
| Thrust (floor / vacuum) | 1517 kN / 1961 kN |
| Specific impulse (soil / vacuum) | 359 s / 455 s |
Web links
- ЖРД РД-0120 (11Д122) (Russian)
Individual evidence
- ↑ a b RD-0120 in the Encyclopedia Astronautica (English)
- ↑ Description and pictures ЖРД РД-0120 (Russian)