A boundary layer ingestion fan system for location aft of the fuselage of an aircraft includes a nacelle (501) defining a duct (502), and a fan (503) located therewithin. The fan comprises a hub which rotates around a rotational axis (A-A) and a plurality of blades attached thereto. Each blade has a span (r) from a root at the hub defining a 0 percent span position (r=0) to a tip defining a 100 percent span position (r=1) and a plurality of span positions therebetween (r∈[0, 1]), a leading edge and a trailing edge defining, for each span position, a chord therebetween having a chord length (c), and a blade thickness (t) defined for each span position thereof. For each blade, a ratio of thickness at the 0 percent span position (t.sub.hub) to chord length is 0.1 or greater.

A method to control flow separation over an airfoil, turbine blade or compressor blade includes providing an airfoil having a body with an upper surface and a lower surface that extend from a leading edge to a trailing edge; providing a flow separation control device having a plurality of openings on the upper surface of the body and a plurality of capillary tubes in gaseous communication with the plurality of openings; and injecting gas through the plurality of capillary tubes into a portion of the airstream passing over the uppers surface of the body.

An active laminar flow control arrangement may comprise a variable speed constant frequency (VSCF) converter comprising a housing, a compressor, an electric motor operably coupled to the compressor, and a laminar flow control duct. An airflow is received by the housing from the laminar flow control duct in response to the electric motor driving the compressor for cooling the VSCF converter.

A combination of an airfoil, turbine blade, or compressor blade with a flow separation control device includes an airfoil, a flow separation control device, and an injection system. The airfoil includes a body with an upper surface and a lower surface that extend from a leading edge to a trailing edge. The flow separation control device includes a plurality of openings on the upper surface of the body. The injection system includes an inlet tube, a pump in gaseous communication with the inlet tube, and a flow regulator in gaseous communication with the pump and the plurality of capillary tube.

An air-jet cooling device for a casing of a turbomachine, in particular a turbine casing, including a cooling air housing having a wall, and a tube having a first end mounted on the wall of the housing so as to put the tube into fluid communication with the housing, orifices being formed in a wall of the tube in order to eject the cooling air coming from the housing on the casing. The tube has a section at the first end with a gradual variation that defines a boss. The boss has a curved surface to be immersed in the cooling air so as to avoid a detachment of a boundary layer of the cooling air at an interface between the first end of the tube and the housing.

Device and methods for guiding bleed air in a turbofan gas turbine engine are disclosed. The devices provided include louvers and baffles that guide bleed air toward a bypass duct of the turbofan engine. The louvers and baffles have a geometric configuration that promotes desirable flow conditions and reduced energy loss.

An inlet flow distortion control system employs a plurality of flow control devices forming at least one array integrated into an internal surface of the inlet. The at least one array extends over an azimuthal range relative to a normal flow axis of the inlet and has a plurality of circumferential rows spaced at increasing distance from a highlight of the inlet. A control system is operably connected to the flow control devices and adapted to activate flow control devices in selected subarrays of the array responsive to a predetermined flight condition.

A powered augmented fluid turbine for generating electricity from a fluid in motion comprising: a central annular ducted channel extending between an inlet distribution header and an outlet distribution header, the channel comprising a converging section configured to accelerate the fluid received at the inlet distribution header, a turbine assembly for generating electricity, and a diffuser section configured to decelerate the fluid before it exits at the outlet distribution header; a recycle line for transporting the exiting fluid to the inlet distribution header in a closed-loop configuration, the recycle line comprising a recycle line propulsor controllable by a recycle line controller and a recycle line heat exchanger; and a compressed fluid distribution line configured to pressurize the fluid in motion by transporting a compressed fluid from a compressed fluid source to the inlet and outlet distribution headers, the compressed fluid distribution line controllable by at least one pressure controller.

A powered augmented fluid turbine for generating electricity from a fluid in motion comprising: a central annular ducted channel extending between an inlet distribution header and an outlet distribution header, the channel comprising a converging section configured to accelerate the fluid received at the inlet distribution header, a turbine assembly for generating electricity, and a diffuser section configured to decelerate the fluid before it exits at the outlet distribution header; a recycle line for transporting the exiting fluid to the inlet distribution header in a closed-loop configuration, the recycle line comprising a recycle line propulsor controllable by a recycle line controller and a recycle line heat exchanger; and a compressed fluid distribution line configured to pressurize the fluid in motion by transporting a compressed fluid from a compressed fluid source to the inlet and outlet distribution headers, the compressed fluid distribution line controllable by at least one pressure controller.

A stator blade for a centrifugal compressor having a front portion configured to generate one or more strear-wise vortices in the gas flow around the stator blade in order to avoid and/or delay a detachment of the gas flow from the suction surface of the stator blade especially when the centrifugal compressor is not operating at its operational design speed.