Propellant Feed SystemHigh Pressure Fuel Pumpby Aerojet Rocketdyne (Rocketdyne)
Typical Specifications
Speed
35,360 RPM
Power
55.4 MW (74,300 hp)
Discharge Pressure
~45 MPa
Flow Rate
~70 kg/s LH2
Operating Principle
Fuel-rich hot gas from the fuel preburner drives a two-stage axial turbine at 35,360 RPM, which directly drives a three-stage centrifugal hydrogen pump, raising pressure from 1.7 MPa to approximately 45 MPa.
The RS-25 High Pressure Fuel Turbopump is one of the most remarkable rotating machines ever built, spinning at over 35,000 RPM to pressurize liquid hydrogen to 45 MPa. Each HPFTP produces approximately 55 MW of power—equivalent to a small power plant—in a package smaller than a car engine. It is a two-stage centrifugal pump driven by a two-stage hot-gas turbine.
Materials
Used In Engines
Common Failure Modes
Turbine blade cracking, bearing wear, hydrogen embrittlement, rotor dynamics instability, seal degradation, thermal fatigue
Recent Innovations
Hydrostatic bearings eliminate rubbing contact, two-stage turbine for efficiency, three-stage pump for extreme pressure ratio, extensive hydrogen-compatible material development
