Methods and apparatus for cooling a surface on a flight vehicle and/or generating power include advancing the flight vehicle at a speed of at least Mach 3 to aerodynamically heat the surface. A supercritical working fluid is circulated through a fluid loop that includes compressing the supercritical working fluid through a compressor, heating the supercritical working fluid through a heat intake that is thermally coupled to the surface, expanding the supercritical working fluid in a thermal engine to generate a work output, cooling the supercritical working fluid, and recirculating the supercritical working fluid to the compressor. The work output of the thermal engine is operably coupled to the compressor, and may optionally be coupled to a generator to produce power. The supercritical working fluid absorbs heat from the surface, eliminating hot spots and permitting use of lighter and/or less expensive materials.

Airframe integrated scramjet engines are disclosed. Scramjet engines within the scope of this disclosure may be configured to integrate smoothly with an airframe of a hypersonic flight aircraft or vehicle. The scramjet engine may include capture shape of an inlet configured to capture airflow, a combustor configured for combustion of fuel and air, and an exit shape of a nozzle configured for expansion of the combusted fuel and air to provide hypersonic thrust. In some embodiments, the scramjet engine has a fixed geometry and a transitioning cross-sectional shape over its full length. The scramjet engine is configured to be a component of launch vehicle system.

An air-breathing turbojet engine for a hypersonic vehicle is shown. The engine comprises a pump for pumping a cryogenic fuel, an inlet configured to compress inlet air by one or more shocks, a cooler to cool the compressed inlet air using the cryogenic fuel, and a turbo-compressor to compress the air further. A precooler cools the compressed inlet air using compressed cooled air from the turbo-compressor. A combustor receives compressed cooled air from the turbo-compressor and a first portion of the cryogenic fuel for combustion. A first turbine expands and is driven by combustion products, and a second turbine expands and is driven by a second portion of the cryogenic fuel. The first turbine and the second turbine drive the turbo-compressor via a shaft. An afterburner receives combustion products from the first turbine and the second portion of the cryogenic fuel from the second turbine for combustion therein.

An aircraft propulsion system includes an engine. The propulsion system further includes an inlet having a forward cowl lip and an aft cowl lip. The forward cowl lip moves between retracted and deployed positions. The forward cowl lip is adjacent to the aft cowl lip when retracted. The forward cowl lip is spaced apart from the aft cowl lip when deployed. The forward cowl lip has a smaller radius of curvature than the aft cowl lip. The propulsion system further includes a controller coupled with the engine and inlet. The controller restricts the maximum thrust commanded position of the engine when the aircraft is on the ground and moving below a predetermined speed. The controller lifts the restriction when the aircraft is moving at at least the predetermined speed. The controller controls the inlet to deploy the cowl lip when the aircraft is on the ground.

A flight vehicle has an engine that includes air inlet, an isolator (or diffuser) downstream of the air inlet, and a combustor downstream of the isolator. The isolator includes a bulged region that has at least one dimension, perpendicular to the direction of the air flow from the inlet to the combustor, that is at a local maximum, larger than comparable isolator dimensions both upstream and downstream of the bulged region. The bulged region stabilizes shocks within the isolator, and facilitates flow mixing. The flow diversion of high energy flow around the outermost walls of the bulged section into the center of the flow at the aft end of the isolator, increases mixing of the flow, and results in a more consistent flow profile entering the combustor over a wide range of flight conditions (Mach, altitude, angle-of-attack, yaw) and throttle settings.

In a jet engine having a core that sources a first flow of fluid and a component (such as a fan, a pump, and/or a bleed line) that sources a second flow of fluid, and where the first flow of fluid will typically have, at least during ordinary operation, a higher temperature than the second flow of fluid, at least one flow aperture formed by a first passageway to receive at least a portion of the aforementioned second flow of fluid, wherein that first passageway is comprised of at least one material that (by design and intent) deflects as a function of temperature such that a flow of the second flow of fluid through the at least one flow aperture is thereby desirably modulated.

A new dual-mode ramjet combustor used for operation over a wide flight Mach number range is described. Subsonic combustion mode is usable to lower flight Mach numbers than current dual-mode scramjets. High speed mode is characterized by supersonic combustion in a free-jet that traverses the subsonic combustion chamber to a variable nozzle throat. Although a variable combustor exit aperture is required, the need for fuel staging to accommodate the combustion process is eliminated. Local heating from shock-boundary-layer interactions on combustor walls is also eliminated.

A high-Mach engine includes a gas turbine core, an inlet assembly, and a transmission. The inlet assembly including an inlet turbine and the transmission configured to couple the inlet turbine and a core turbine of the gas turbine core cooperate to control air moving through the high-Mach engine.

A swept gradient air boundary layer diverter for an aircraft. The aircraft includes a fuselage and an air inlet for an engine of the aircraft, where the air inlet includes a cowl at a leading edge of the inlet. The diverter includes a V-shaped ramp portion formed in the fuselage in an area proximate to and in front of the cowl where the ramp portion extends downward away from an outer surface of the fuselage towards an inside of the aircraft. The diverter also includes a V-shaped trough portion formed into the fuselage and being positioned adjacent to and integral with the ramp portion between the ramp portion and the air inlet. Air flowing over the fuselage towards the cowl is expanded and compressed by the ramp portion and the trough portion so as to create pressure gradients that generate vortices to redirect boundary layer airflow around the air inlet.

An inlet arrangement is disclosed herein for use with a supersonic jet engine configured to consume air at a predetermined mass flow rate when the supersonic jet engine is operating at a predetermined power setting and moving at a predetermined Mach speed. The air inlet arrangement includes, but is not limited to, a cowl having a cowl lip and a center body coaxially aligned with the cowl. A protruding portion of the center body extends upstream of the cowl lip for a length greater than a conventional spike length. The protruding portion is configured to divert air flowing over the protruding portion out of a pathway of an inlet to the supersonic jet engine such that a remaining airflow approaching and entering the inlet matches the predetermined mass flow rate.