RD-701
 
|
The RD-701 is a unique advanced rocket engine
configuration incorporating the advantages of tripropellant operation. The engine
operates with all three propellants (lox, kerosene, hydrogen) in the booster mode (mode 1)
and transitions to bipropellant operation (lox, hydrogen) for the latter portion of the
trajectory (mode 2). The hydrogen cooled thrust chamber has three component injector
mixing elements with the kerosene element not used in mode 2. In mode 1 operation the
hydrogen enhances the combustion of the kerosene to provide to tripropellant specific
impulse levels higher than obtainable with separate combustion of the fuels. |
The RD-701 is a fully integrated propulsion unit with two
thrust chambers and their associated high pressure turbopumps and preburners incorporated
into a thrust frame with common boost pumps, hydraulic system, and pneumatic system. The
RD-170 provides the high pressure, oxygen rich powered, lox/kerosene enabling technology
for the RD-701, as well as the mature health monitoring and operability systems necessary
for the fully reusable, low cost operation envisioned for this engine.
| Advantages of tripopellant
configuration: |
| - |
High bulk density propellant for low altitude
and high specific impulse for high altitude |
| - |
High chamber pressure (power density) with
moderate H2 pump pressures |
| - |
Hydrocarbon can be stored in wings of vehicle |
| - |
H2 available to cool thrust chamber |
| - |
Increased combustion efficiency for hydrocarbon |
| - |
Improved combustion stability characteristics |
| • |
Dimensions |
|
|
Length of one chamber
(in.) |
196.9 |
|
Exit Diameter of the
nozzle (in.) |
90.6 |
|
Dry Weight of engine
assembly (lbs.) |
9156 |
| • |
Staged combustion power cycle (oxidizer rich) |
|
| • |
Thrust (SL) (Vacuum) |
714,000/9000,000 lbs. (mode 1) |
|
|
357,000 Lbs. (mode 2) |
| • |
Isp (SL) (Vacuum) |
330/415 sec. (mode 1) |
|
|
460 sec. (mode 2) |
| • |
Throttle |
32-100% |
| • |
Oxidizer |
Oxygen - Hydrogen |
| • |
Fuel |
Kerosene (mode 1) |
|
|
Hydrogen (mode 2) |
| • |
Chamber Pressure |
4,266 psia (mode 1) |
|
|
1,792 psia (mode 2) |
| • |
Mixture ratio |
|
|
(mode 1) |
Lox 81.4%, Kerosene 12.6%, Hydrogen 6% |
|
(mode 2) |
6.1 |
| • |
Nozzle Area Ratio |
123.4 |
| • |
Preburner |
2 per chamber |
| • |
Thrust Chamber Assemblies |
2 |
| • |
Ignition |
Hypergolic |
|
