The RD -0120 (from Russian Реактивный двигатель, " Reaktiwnyj Dwigatel " German rocket engine, GREY index 11D122, internal designation RO- 200) is a rocket engine for liquid rocket. It should not be confused with the RD -120 ( 11D123 ) the Zenit rocket that reaches a much smaller boost.
Development and use
The RD -0120 was developed by the Soviet designer of rocket motors Semyon Kosberg in the period 1976-1990 in the Chemical Automatics Design Bureau and is now marketed by TsSKB -Progress. The engine was used as a drive for the central stage (second stage ) of the Energia rocket is driven by four of each equipped with a combustion chamber RD -0120 engines. The first test with full thrust were made in May 1984, the first flight in May 1987 and the last use in 1988. Later variants with methane instead of hydrogen as a fuel (RD- 0120- CH) and enhanced variants (RD- 0120M and RD were 0122) tested.
The RD -0120 is operated similarly to the main engines ( SSME ) of the Space Shuttle with liquid hydrogen and oxygen ( LH2/LOX ), which was a first for the Soviet space program at the time. It can be adjusted up to 55 % of its full power down. There are backing pumps, the hydraulic ( oxygen ) or with the energy from the combustion chamber cooling ( hydrogen) are operated. The main pumps for fuel and oxidizer, and a two-stage turbine located on a single common shaft. The energy to drive the turbine is derived from a single sub-chamber in which the major part of the hydrogen is precombusted with a small portion of the oxygen at a lower temperature before it is supplied to the main combustion chamber. As with the SSME so comes the RD -0120 is a mainstream method of fuel-rich pre-combustion (fuel rich staged combustion, FRSC ) are used, while the SSME a more complex design with two shafts and two pre-combustion chambers comes each Oxidatorhauptpumpe and the hydrogen main pump for use. Running as a main stream engine is at the desired high combustion chamber pressures mandatory, as only so in contrast to the side -flow process (gas generator cycle) no fuel is lost through the bleed in the gas generator for the main combustion chamber.