Abstract: 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.

Abstract: A propulsion system for an aircraft includes: (1) an engine configured to generate a mass flow, (2) a nozzle having a pathway having a throat and a trailing edge, the throat or the trailing edge being configured to enlarge and contract, (3) a deployable obstructer disposed in the nozzle, (4) a first pressure sensor to sense the static pressure of the mass flow at the nozzle exit, (5) a second pressure sensor to sense the ambient pressure proximate the aircraft, and a (6) controller. The controller is coupled with the first and second pressure sensors, the deployable obstructer, and the throat or the trailing edge (whichever is configured to enlarge and contract). The controller receives the static and ambient pressures and when there is a disparity, the controller controls at least one of the deployable obstructer, the throat, and the trailing edge in a manner that reduces the disparity.

Abstract: An arrangement for use with a propulsion system for a supersonic aircraft includes a center body configured for coupling to an inlet and to support a boundary layer formed when the supersonic aircraft is flown at a predetermined altitude supersonic speed. The arrangement further includes a first vortex generator disposed on the center body. The first vortex generator extends a first height above the center body. The arrangement still further includes a second vortex generator disposed on the center body. The second vortex generator extends a second height above the center body, the second height being greater than the first height. The first height and the second height are greater than approximately seventy-five percent of a thickness of the boundary layer proximate a location of the first vortex generator and the second vortex generator, respectively, when the aircraft if flown at the predetermined altitude and the predetermined speed.

Abstract: A supersonic inlet includes a relaxed isentropic compression surface to improve net propulsive force by shaping the compression surface of the inlet to defocus the resulting shocklets away from the cowl lip. Relaxed isentropic compression shaping of the inlet compression surface functions to reduce the cowl lip surface angle, thereby improving inlet drag characteristics and interference drag characteristics. Supersonic inlets in accordance with the invention also demonstrate reductions in peak sonic boom overpressure while maintaining overall engine performance.

Abstract: A propulsion system for an aircraft includes: (1) an engine configured to generate a mass flow, (2) a nozzle having a pathway having a throat and a trailing edge, the throat or the trailing edge being configured to enlarge and contract, (3) a deployable obstructer disposed in the nozzle, (4) a first pressure sensor to sense the static pressure of the mass flow at the nozzle exit, (5) a second pressure sensor to sense the ambient pressure proximate the aircraft, and a (6) controller. The controller is coupled with the first and second pressure sensors, the deployable obstructer, and the throat or the trailing edge (whichever is configured to enlarge and contract). The controller receives the static and ambient pressures and when there is a disparity, the controller controls at least one of the deployable obstructer, the throat, and the trailing edge in a manner that reduces the disparity.

Abstract: A propulsion system for an aircraft includes (1) an engine configured to generate a mass flow, (2) a nozzle having a pathway having a throat and a trailing edge, one of the throat and the trailing edge configured to enlarge and contract, (3) a heat source disposed in the nozzle, (4) a first pressure sensor to sense the static pressure of the mass flow at the nozzle exit, (5) a second pressure sensor to sense the ambient pressure proximate the aircraft, and a (6) controller. The controller is coupled with the first and second pressure sensors, the heat source, and the throat or the trailing edge (whichever is configured to enlarge and contract). The controller receives the static and ambient pressures and when there is a disparity, the controller controls at least one of the heat source, the throat, and the trailing edge in a manner that reduces the disparity.

Abstract: An arrangement for use with a propulsion system for a supersonic aircraft includes a center body configured for coupling to an inlet and to support a boundary layer formed when the supersonic aircraft is flown at a predetermined altitude supersonic speed. The arrangement further includes a first vortex generator disposed on the center body. The first vortex generator extends a first height above the center body. The arrangement still further includes a second vortex generator disposed on the center body. The second vortex generator extends a second height above the center body, the second height being greater than the first height. The first height and the second height are greater than approximately seventy-five percent of a thickness of the boundary layer proximate a location of the first vortex generator and the second vortex generator, respectively, when the aircraft if flown at the predetermined altitude and the predetermined speed.

Abstract: A propulsion system for a supersonic aircraft includes an engine including an engine core and an engine bypass, a compression surface upstream of the engine, a shroud surrounding the engine configured to direct airflow passing over the compression surface towards the engine, and a plurality of vortex generators positioned upstream of the engine. The vortex generators have a height such that when the supersonic aircraft is flown at a predetermined altitude and predetermined speed, the plurality of vortex generators create vortices that propagate partially outside of a boundary layer formed proximate a surface of a supersonic inlet. The vortices cause a high-velocity portion of the airflow to move towards the engine core and a low-velocity portion of the airflow to move towards the engine bypass. The plurality of vortex generators are disposed aft of a terminal shock and have a height greater than the thickness of the boundary layer.

Abstract: A supersonic inlet includes a relaxed isentropic compression surface to improve net propulsive force by shaping the compression surface of the inlet to defocus the resulting shocklets away from the cowl lip. Relaxed isentropic compression shaping of the inlet compression surface functions to reduce the cowl lip surface angle, thereby improving inlet drag characteristics and interference drag characteristics. Supersonic inlets in accordance with the invention also demonstrate reductions in peak sonic boom overpressure while maintaining overall engine performance.

Abstract: A supersonic inlet includes a relaxed isentropic compression surface to improve net propulsive force by shaping the compression surface of the inlet to defocus the resulting shocklets away from the cowl lip. Relaxed isentropic compression shaping of the inlet compression surface functions to reduce the cowl lip surface angle, thereby improving inlet drag characteristics and interference drag characteristics. Supersonic inlets in accordance with the invention also demonstrate reductions in peak sonic boom overpressure while maintaining overall engine performance.

Abstract: 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.

Abstract: A supersonic inlet includes a relaxed isentropic compression surface to improve net propulsive force by shaping the compression surface of the inlet to defocus the resulting shocklets away from the cowl lip. Relaxed isentropic compression shaping of the inlet compression surface functions to reduce the cowl lip surface angle, thereby improving inlet drag characteristics and interference drag characteristics. Supersonic inlets in accordance with the invention also demonstrate reductions in peak sonic boom overpressure while maintaining overall engine performance.

Abstract: 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.

Abstract: A nozzle arrangement is disclosed herein for use with a supersonic jet engine that is configured to produce a plume of exhaust gases. The nozzle arrangement includes, but is not limited to, a nozzle having a trailing edge and a plug body partially positioned within the nozzle. The plug body has an expansion surface and a compression surface downstream of the expansion surface. A protruding portion of the plug body extends downstream of the trailing edge for a length greater than a conventional plug body length. The plug body is configured to shape the exhaust gases to flow substantially parallel to a free stream of air flowing off of the trailing edge of the nozzle and to cause the plume of exhaust gases to isentropically turn the free stream of air to move in a direction parallel to a longitudinal axis of the plug body.

Abstract: A supersonic inlet having a cowl lip configured to capture the conic shock and exhibit a zero or substantially zero cowl angle is disclosed herein. The inlet may be configured to employ a relaxed isentropic compression surface and an internal bypass. The nacelle bypass may prevent flow distortions, introduced by the capture of the conic shock, from reaching the turbomachinery, thereby allowing the cowl angle to be reduced to zero or substantially zero. Such a cowl angle may reduce the inlet's contribution to the overall sonic boom signature for a supersonic aircraft while allowing for an increase in engine pressure recovery and a subsequent improvement in generated thrust by the engine.

Abstract: A supersonic nacelle design employing a bypass flow path internal to the nacelle and around the engine is disclosed herein. A set of aerodynamic vanes may be used to shape a supersonic airflow within a bypass around an engine. The vanes may be capable of compressing the supersonic airflow into a subsonic airflow, direct the subsonic airflow around the engine, and then expand the subsonic airflow into a supersonic exhaust. The vanes may shape the airflow by reducing sonic boom strength, cowl drag, and airframe interference drag.

Abstract: A supersonic nacelle design employing a bypass flow path internal to the nacelle and around the engine is disclosed herein. A set of aerodynamic vanes may be used to shape a supersonic airflow within a bypass around an engine. The vanes may be capable of compressing the supersonic airflow into a subsonic airflow, direct the subsonic airflow around the engine, and then expand the subsonic airflow into a supersonic exhaust. The vanes may shape the airflow by reducing sonic boom strength, cowl drag, and airframe interference drag.

Abstract: A propulsion system for a supersonic aircraft includes an engine, a compression surface upstream of the engine, a shroud surrounding the engine configured to direct airflow passing over the compression surface towards the engine, and a plurality of vortex generators positioned upstream of the engine. The vortex generators have a height such that when the supersonic aircraft is flown at a predetermined speed, the plurality of vortex generators create a plurality of vortices that propagate partially outside of a boundary layer formed proximate a surface of a supersonic inlet. The vortices cause a high-velocity portion of the airflow to move towards a portion of the engine having a higher sensitivity to changes in stagnation pressure and a low-velocity portion of the airflow to move away from the portion of the engine having the higher sensitivity to changes in stagnation pressure prior to the airflow reaching a face of the engine.

Abstract: A supersonic nacelle design employing a bypass flow path internal to the nacelle and around the engine is disclosed herein. A set of aerodynamic vanes may be used to shape a supersonic airflow within a bypass around an engine. The vanes may be capable of directing the subsonic airflow around the engine, and then expanding the subsonic airflow into a supersonic exhaust. The vanes may shape the airflow by reducing sonic boom strength, cowl drag, and airframe interference drag.

Abstract: A nozzle arrangement is disclosed herein for use with a supersonic jet engine that is configured to produce a plume of exhaust gases. The nozzle arrangement includes, but is not limited to, a nozzle having a trailing edge and a plug body partially positioned within the nozzle. The plug body has an expansion surface and a compression surface downstream of the expansion surface. A protruding portion of the plug body extends downstream of the trailing edge for a length greater than a conventional plug body length. The plug body is configured to shape the exhaust gases to flow substantially parallel to a free stream of air flowing off of the trailing edge of the nozzle and to cause the plume of exhaust gases to isentropically turn the free stream of air to move in a direction parallel to a longitudinal axis of the plug body.