Liquid rocket engine RD-8
LRE is intended to control flight of the Zenit LV second stage in all channels.
- The steering engine operating under the scheme of staged combustion (afterburning of the generator gas).
- High reliability (the POS pointed evaluation is no less than 0,995);
- High service life (more than 4000 s);
- Delivery to service after the check-technological firing test without following refurbishment.
- Shutdown possibility under depletion of any propellant component.
- Possibility to modernize the engine for the second run in flight.
- The combustion chamber is a basis for developing engines of 2 and 4 tf thrust.
The autonomous four-chamber pump-fed steering engine of a single run.
The stage flight control is provided by gimbaling each chamber in one tangential plate.
Within the said class of engines, the RD-8 is designed for the first time in the world practice under the scheme of staged
The working medium of the TPU turbine is an oxidizer-rich gas.
The TPU rotor is spinned up during the startup by pneumatic starter.
The propellants are ignited in the gas generator and chambers under use of a starting fuel.
The control units are fed with Helium through electropneumatic valves.
The engine operates in a single mode and provides maintenance of specified thrust and propellants mixture ratio.
The engine's pressure indicators issue shutdown commands at propellants depletion in LV tanks. An emergency shutdown is foreseen under
command of one of indicators.
The engine may stay in the rocket filled with propellants within 24 hours.
Design of the engine allows performance of multiple bench firing tests.
Each engine is delivered to the LV integration after a check-technological firing test without following refurbishment.
|Vacuum thrust, kgf||8000|
|Vacuum specific impulse, s||342|
|Combustion chamber absolute pressure, kgf/cm2||78|
|Nozzle exit absolute pressure, kgf/cm2||0.05|
|Thrust maintenance accuracy, %||±4.5|
|Range of MR regulation, %||±8|
|Propellants ignition in the gas generator and chambers||By starting fuel|
|Min absolute inlet pressure, kgf/cm2:
- oxidizer (at temperature of minus 175°C)
- fuel (at temperature of 12°C)
|Gimbal angle of chambers, deg.||±33|
|Firing time, s||1100|