A gas turbine engine comprises a fan drive gear system, a low spool connected to the fan drive gear system, and a high spool disposed aft of the low spool. The low spool comprises a rearward-flow low pressure compressor disposed aft of the fan drive gear system, and a forward-flow low pressure turbine disposed aft of the low pressure compressor. The high spool comprises a forward-flow high pressure turbine disposed aft of the low pressure turbine, a combustor disposed aft of the high pressure turbine, and a forward-flow high pressure compressor disposed aft of the combustor.

Reversed-flow core for a turbofan with a fan drive gear system

A supersonic external-compression inlet (20) comprises a generally scoop-shaped supersonic compression section for diffusing a supersonic free stream flow (24). The supersonic compression section includes a main wall having a leading edge (28) and a throat portion downstream of the leading edge (28), and side portions joined to opposite side edges of the main wall so as to form a generally scoop-shaped structure. The side portions advantageously extend into the supersonic flow stream far enough to encompass the initial oblique shock wave that is attached to the leading edge of the main wall. The main wall has an inner surface (22) formed generally as an angular sector of a surface of revolution, the inner surface (22) of the main wall coacting with inner surfaces of the side portions to define a three-dimensional external-compression surface. The supersonic external-compression inlet (20) also includes a subsonic diffuser section arranged to receive flow from the supersonic compression section and to diffuse the flow to a subsonic condition. A variable-geometry inlet includes an external ramp hinged about its forward edge and forming a portion of the inner surface of the scoop-shaped diffuser, pivotal movement of the external ramp serving to vary a throat size of the inlet. The subsonic diffuser (20) includes an internal ramp hinged about its aft edge for maintaining a smooth transition from the external ramp.

Supersonic external-compression diffuser and method for designing same

An internal compression engine inlet (39) including a flexible external cowl with leading edge cowl lips (72); a duct comprising a supersonic diffuser (44) defined by upper and lower forward ramps (50), (52), a subsonic diffuser (46) defined by upper and lower aft ramps (54), (56), and a throat region (48); a first slot (58) formed between adjacent ends of the upper forward and upper aft ramps; and a second slot (60) formed between adjacent ends of the lower forward and lower aft ramps, is provided. Each slot (58), (60) opens to a plenum (120), (122) having a vent door (126) covering a vent (124) that opens to a low pressure volume. Further inlet components include an optional splitter (62) for creating additional airflow compression, a precision vent (128) for expelling small amounts of plenum air, and a control system (150) for varying the cross-sectional area of the duct and the position of the vent doors in order to create an aerodynamically efficient airflow passage within the duct for any particular flight condition. Further provided is a method of providing air to an aircraft engine using an internal compression engine inlet including: sensing current flight conditions; configuring the inlet components to their optimal positions for the current flight conditions; channeling air into a duct having a supersonic diffuser region followed by a throat region having first and second slots each slot opening into a plenum, the throat region being followed by a subsonic diffuser; sensing the static air pressure in the supersonic diffuser; sensing the static air pressure within each plenum; comparing the supersonic diffuser static air pressure with the plenum air pressures; and selectively exhausting air from each plenum to maintain the static air pressure in the plenums at a desired amount.

Internal compression supersonic engine inlet

A two-dimensional inlet for a high speed ram jet missile includes in combination an educated slot and a single ramp for varying the geometry of the inlet.

Variable-geometry inlet

A mixed compression inlet having a forward ramp, an aft ramp, and a slot therebetween is disclosed. The aft ramp is coupled to the inlet to permit both fore-aft movement and rotational movement. The geometric throat of the inlet is located at the leading edge of the aft ramp. The slot opens into a plenum chamber. A vent permits air to exit from the plenum chamber. The pressure in the plenum chamber is maintained approximately equal to the pressure on the aft portion of the forward ramp. A servocontroller receiving input from pressure sensors of the forward ramp and in the plenum chamber controls the position of a vent door to ensure that the proper pressure is maintained within the plenum chamber.

Two-stage supersonic inlet

A propulsion power plant for use in a supersonic aircraft includes an aft-fan engine housed in a first duct which delivers air both to the aft-fan and to a further duct for delivery to the gas-generator portion of the engine, the intake of the further duct being positioned within the first duct so that it captures the relatively smooth airflow in the middle of the duct for delivery over a relatively short distance to the gas-generator, the relatively turbulent air at the edges of the first duct being delivered o the aft-fan over a relatively longer distance.

Goldsmith H

Papers

Propulsion power plant for aircraft