An aero-propulsion system includes a drive shaft, a low-pressure compressor, a fan shaft driving a fan, a reduction device that couples the drive shaft and the fan shaft, and an inlet channel which extends between the fan and the low-pressure compressor, the inlet having a predetermined mean radius, a ratio between a mean radius of the inlet channel and the mean radius of the low-pressure compressor, on the one hand, and the reduction ratio of the reduction mechanism, on the other hand, being less than 0.35.

An integrated flow source is a limiting factor in numerous microfluidic applications. In addition to precise gradients and controlling molecular transports, a built-in source of stable and accurate flow can enable novel shear stress modulations for long-term cell culturing studies. The Tesla turbine, when used as a pump on the microfluidic regime, produces stable and accurate fluid gradients by utilizing laminar flow between its rotating discs Utilizing a stereolithography based 3D printer, a tesla pump (Ø10 cm) and associated housing capable of driving a microfluidic gradient is provided having a printed rotor surface topology of the pump in order to enhance pumping of biological fluids like blood at elevated viscosities. The surface topology is tuned via 3D pixilation, and this modulation completely recovered the pressure loss between pumping water at 1 cP versus glycerol solution at 3 cP. As a result, increased fluid viscosities, and even Non-Newtonian viscosities, can be used.

A recuperator disposed in the exhaust duct of a gas turbine engine includes a plurality of recuperator plates arranged in a spaced-apart relationship to define therebetween a plurality of interstices and fluid channels, the plurality of interstices adapted to direct therethrough at least one first stream received at a leading plate edge of the recuperator plates and the plurality of fluid channels adapted to direct therethrough at least one second stream to effect heat exchange between the at least one first stream and the at least one second stream. Each recuperator plate includes, formed at the leading plate edge thereof, a first concavity extending along the leading edge in a direction substantially parallel to a longitudinal axis of the plate. The first concavity extends transversely to a direction of the at least one first stream flowing over each recuperator plate.

To provide a stator vane of a fan or compressor that is reduced in loss by enlarging a laminar flow area over a blade surface. With the stator vane, provided that an angle formed by a tangent to the blade surface at a point and the axial direction of the turbofan engine, that is, a parameter that is a blade surface angle normalized is referred to as a normalized blade surface angle, an upper limit is set for the change rate in the chord direction of the normalized blade surface angle on the pressure surface, and an upper limit is set for the normalized blade surface angle at a predetermined location in the chord direction on the suction surface.

An integrated flow source is a limiting factor in numerous microfluidic applications. In addition to precise gradients and controlling molecular transports, a built-in source of stable and accurate flow can enable novel shear stress modulations for long-term cell culturing studies. The Tesla turbine, when used as a pump on the microfluidic regime, produces stable and accurate fluid gradients by utilizing laminar flow between its rotating discs Utilizing a stereolithography based 3D printer, a tesla pump (Ø10 cm) and associated housing capable of driving a microfluidic gradient is provided having a printed rotor surface topology of the pump in order to enhance pumping of biological fluids like blood at elevated viscosities. The surface topology is tuned via 3D pixilation, and this modulation completely recovered the pressure loss between pumping water at 1 cP versus glycerol solution at 3 cP. As a result, increased fluid viscosities, and even Non-Newtonian viscosities, can be used.

A propulsion system includes a drive shaft movable in rotation about an axis of rotation, a low-pressure compressor driven in rotation by the drive shaft, the low-pressure compressor having a mean radius, a fan shaft, a fan driven in rotation by the fan shaft, a reduction mechanism coupling the drive shaft and the fan shaft, having a reduction ratio, and an inlet channel which extends between the fan and the low-pressure compressor, the inlet channel having an inlet adjacent to the fan and an outlet opposite the inlet and adjacent to the low-pressure compressor, the inlet having a mean radius. A first ratio between a ratio of a mean radius of the inlet channel and the mean radius of the low-pressure compressor, and the reduction ratio of the reduction mechanism, is strictly less than 0.35.

An assembly is provided for active laminar flow control. This assembly includes a panel, which panel includes an outer skin, an inner skin and a plurality of plenums between the outer skin and the inner skin. Each of the plurality of plenums is fluidly coupled with a respective array of perforations through the outer skin. The panel is constructed from fiber-reinforced composite material.

An assembly is provided for an aircraft propulsion system. This assembly includes a forward thrust duct and a thrust reverser system. The thrust reverser system includes a thrust reverser duct, a bullnose ramp and a plurality of protrusions. The bullnose ramp is adapted to provide a transition from the forward thrust duct to the thrust reverser duct when the thrust reverser system is in a deployed configuration. The protrusions are bonded or formed integral with the bullnose ramp. Each of the protrusions is adapted to interact with boundary layer fluid flowing along the bullnose ramp from the forward thrust duct into the thrust reverser duct when the thrust reverser system is in a deployed configuration.

A blade of a fan or compressor that reduces loss by enlarging a laminar flow region over a blade surface is provided. The blade is divided into a subsonic region where the relative Mach number of the inlet air flow during rated operation of a turbofan engine is lower than 0.8 and a transonic region where the relative Mach number is equal to or higher than 0.8. A blade surface angle change rate is based on an angle formed by a tangent to the blade surface and the axis of the engine, the leading edge blade surface angle, and the trailing edge blade surface angle at. In each of the subsonic region and the transonic region, values of the blade surface angle change rate on the pressure and suction surfaces are defined at predetermined axial locations along the chord on the pressure and suction surfaces.

A Laminar Inducing Apparatus (LIA) inducing laminar airflow to a turbine engine or a propulsion fan. The LIA produces turbulent-free airflow with a light aerospace structure that can replace single purpose structure in the wing or empennage. Laminar airflow to the propulsion fan or the turbine engine is ensured in a greater number of flight conditions and angles of attack. Active control of flight can be enhanced by the manipulating the turbulent boundary surface as a flight control surface. LIA simply reduces the risk of FOD or bird strike damage. In addition to the engineered, laminar benefits, LIA provides greater safety from ground ingested FOD and more silent vertical take-off and landing. In summary, LIA ensures laminar airflow and acoustic attenuation to a propulsion fan or a turbine engine for a greater number of flight conditions, angles of attack, and from ground ingested FOD during vertical takeoff and landing.