Abstract: A monopropellant rocket engine in which nitrous oxide is the propellant includes a catalyst bed on an end of a diverging combustion chamber to inject a first flow of monopropellant to ignite the monopropellant, followed by a series of additional monopropellant injections along the diverging combustion chamber where the previously injected monopropellant decomposes to be used to ignite the downstream injected monopropellant. When all monopropellant has been decomposed, the monopropellant is passed through a throat and nozzle to produce thrust. A control valve is used to regulate an amount of monopropellant injected at each point in order to regulate an amount of thrust.

Abstract: A dual-expander, truncated aerospike rocket engine includes an aerospike nozzle with an oxidizer-cooled nozzle section and a fuel-cooled nozzle section. The engine further includes a fuel pump, an oxidizer pump, and a thrust source. The thrust source combusts fuel and oxidizer in a combustion chamber(s) of a thrust source arranged around the aerospike nozzle. Fuel and oxidizer pumps that pump the fuel and the oxidizer through the nozzle sections are driven by respective turbines.

Abstract: A centrifugal impeller with a single inlet and dual outlets that include a low pressure outlet and a high pressure outlet. The impeller includes low pressure blades with high pressure blades located downstream. The impeller can be shrouded or unshrouded, and can include an inner shroud that forms a flow path for the low pressure fluid and a high pressure flow path for the high pressure fluid. The impeller can include a high pressure volute and a low pressure volute that forms a dual volute with dual diffusers for both fluids.

Abstract: A tapered hydrostatic bearing assembly with a rotor shaft rotating about a stationary shaft in which two tapered hydrostatic bearings are formed to rotatably support the rotor shaft. The stationary shaft includes a bearing fluid passage to channel the bearing fluid to the two tapered hydrostatic bearings. The tapered bearings also function as axial thrust bearings for the rotor shaft.

Abstract: A card seal with an annular arrangement of plates that form the card seal, where the plates are rotated at an angle around a longitudinal axis of the plates so that the gaps between adjacent plates are not parallel to the rotational axis of the rotor shaft, and where an annular disk is rotatably secured to the rotor shaft and located adjacent to card seal on the low pressure side, or on the high pressure side or even on both sides such that rotation of the annular disk pumps fluid into or draws fluid out from the plate gaps to decrease or eliminate any differential pressure across the card seal. Thus, card seal leakage is reduced or eliminated.

Abstract: A hydrodynamic liquid metal bearing capable of use in a high temperature environment. The hydrodynamic bearing includes a rotating shaft with a raised portion extending into an annular groove formed within a stationary sleeve, the space formed between the two forming the liquid bearing surface. The raised portion in the shaft includes an axial passage and a radial passage to pump the liquid into a high pressure cavity formed in the annular groove. A low pressure cavity forms a recirculating passage with the high pressure cavity and the axial and radial passages such that the liquid metal recirculates with the rotation of the shaft. A collecting space formed between a labyrinth seal and a wind back seal collects any fluid that leaks into the space from the bearing. The leaked fluid is collected in a reservoir, and a pump delivers makeup liquid from the reservoir into the low pressure reservoir of the bearing. The bearing is a radial bearing, and in another embodiment is both a radial and a thrust bearing.

Abstract: An expander cycle rocket engine includes a primary nozzle with a heat exchanger formed therein to cool the nozzle and heat up a fluid used to drive a turbo-pump, and a secondary heat exchanger is located within the primary nozzle and includes passages to channel the fluid in order to add additional heat to the fluid used to drive the turbo-pump. The secondary heat exchanger can be a nozzle shaped heat exchanger located within the primary nozzle, and struts that secure the nozzle shaped heat exchanger within the primary nozzle and channel the fluid between nozzles. The concentric arrangement of first and second heat exchangers can transfer more heat from the combustion gases to the fluid that is used to drive the turbo-pump such that higher pressures can be obtained allowing for larger nozzles and much higher thrust than can be obtained with traditional nozzle engines, or provide significantly higher chamber pressures for engines in the prior art thrust class.

Abstract: A twin spool rotor shaft having an inner rotor shaft and an outer rotor shaft concentric to the inner rotor shaft, an outer shaft seal assembly formed between the outer rotor shaft and a stationary casing, and an inner shaft seal assembly formed between the outer shaft and the inner shaft. The two seal assemblies include a purge cavity and two drain cavities formed on the sides of the purge cavity. A purge fluid is supplied to the outer purge cavity, and drain passages in the stationary housing drain the two outer drain cavities without mixing the two fluids. The outer purge cavity is fluidly connected to the inner purge cavity through a radial passage in the outer rotor shaft in one embodiment, or through a bore tube passing within the inner rotor shaft in a second embodiment.

Abstract: A stepped labyrinth seal for a turbomachine, the seal having a stepped portion with a redirecting groove formed thereon to redirect a leakage flow through the gap in substantially a reverse direction and onto a surface of the finger such that the dynamic pressure of the leakage flow is not substantially reduced and the static pressure increased. The cavity formed between adjacent fingers has a flow guiding surface that maintains the dynamic pressure of the flow, thereby keeping the flow at high velocity and low static pressure.

Abstract: A high temperature damper for a roller bearing having a long shelf life and capable of withstanding temperatures in a gas turbine engine shaft. The damper includes a damping chamber formed between a stator housing and the outer race of the bearing, and is filled with a liquid metal such as Gallium that has a paste-like consistency at room temperature so as not to flow and leak from the damping chamber, and a liquid-like consistency at about 1,500 degrees F. in order to withstand the extreme temperatures of a gas turbine engine. Seals having a U-shape cross section are made of a high temperature metal like Hastalloy or Hynes and enclose the liquid metal within the damping chamber.

Abstract: A hydrostatic bearing is uniquely configured for improved operability. A hydrostatic bearing (32) has a collar (42) that circumscribes a shaft (18) to define a fluid film annulus (50) for radially confining a load supportive fluid film. An array of pockets (52) distributed circumferentially along a bearing surface (48) communicate with vent regions (64a, 64b) in which the vent pressures are substantially unequal. Supply passages (76) associated with the pockets (52) are oriented at an angle .theta. for injecting fluid into the annulus with an axial directional component directed toward the higher pressure vent region. The orientation angle .theta. compensates for the propensity of the fluid to preferentially feed the low pressure side of the bearing. Further, a hydrostatic bearing (132) has a collar (142) that circumscribes a shaft (118) to define a fluid film annulus (150) for radially confining a load supportive fluid film.