The invention relates to a nubomachine with a longitudinal axis, comprising two, respectively upstream (122) and downstream, coaxial outer propellers (122), characterised in that at least some of the blades (148) of the upstream propeller (122) comprise at least one internal air circulation chimney (150) that communicates with air-bleeding openings (152) in tire boundary layers of the blades (148), and communicates with air outflow openings (158) on the radially outer end thereof, the air-bleeding openings (152) leading to opening inlets (152a) on tire passive surfaces (156) of the blades (148), the inlets (152a) of the air-bleeding openings being radially arranged in an area (H1) contained between 10% and 45% of the radial dimension (H2) of the blades (148), measured above turd from the radial height of the blades for which the tangent of the leading edge (138) of the blades is orthogonal to the longitudinal axis, and the inlets (152a) of the air bleeding openings being arranged in an area contained between 0% and 30% of the local chord of the blades (148), measured at the level of said inlets (152a) and from the leading edges (138) of tire blades (148).

An aircraft structure (11) for flow control including a perforated panel (13) having an inner surface (15) directed to a structure interior (17), an outer surface (19) in contact with an ambient flow (21), and a plurality of micro pores (23) connecting the inner and outer surfaces (15, 19). Elongate crack stopper elements (25) are attached to the inner surface (15) of the perforated panel (13). The crack stopper elements (25) are configured to inhibit crack propagation within the perforated panel (13).

Apparatuses and methods for controlling fluid flow over surfaces, e.g. wings, are disclosed. A system can include a surface influenced by a fluid flow moving across the surface, a vortex generator disposed proximate to the surface, the vortex generator for altering a vortex pattern within the fluid flow moving across the surface, and a controller for activating the vortex generator to alter the vortex pattern within the fluid flow moving across the surface. The vortex generator can comprise one or more fluid injectors each for injecting a fluid jet into the fluid flow driven by air pressure. The fluid injectors can be disposed along a leading edge of a strake where the strake is disposed on an engine nacelle and the surface comprises an aircraft wing surface. Activation can occur under open or closed loop control with sensors.

Aircraft nacelles having adjustable chines are described. An example apparatus includes a multi-segment chine coupled to a nacelle. The multi-segment chine includes a first segment oriented along a fore-aft direction. The first segment is translatable relative to the nacelle along the fore-aft direction. The multi-segment chine further includes a second segment oriented along the fore-aft direction. The second segment is substantially coplanar with the first segment.

An aerodynamic body includes an upper surface and a lower surface. The upper surface includes a first portion of a first axisymmetric body. The lower surface is mated with the upper surface. The lower surface includes a waverider shape. The waverider shape is derived from the shockwave generated by a second axisymmetric body.

A shock wave suppression device is configured to suppress a shock wave generated on a blade surface of a blade, the shock wave suppression device including a bump cover provided to follow the blade surface and deformable to protrude outward from the blade surface, and a displacing unit configured to displace the bump cover between a steady state to follow the blade surface and a deformed state to protrude outward from the blade surface. The bump cover has a curved shape in the deformed state configured to be a continuous surface from an upstream side to a downstream side in a flow direction of a fluid on the blade surface.

A ducted fan includes a fan and a cowl having a cylindrical shape and including an introduction port configured to introduce air from a first end portion side. The fan includes a compressor blade provided on an outer circumferential side and a thrust blade provided on an inner circumferential side of the compressor blade. The cowl includes a housing portion configured to accommodate the compressor blade in an interior thereof, an outlet configured to allow air flowing through the housing portion to be blown therethrough by the compressor blade, and an inlet configured to suck air blown out. The outlet is provided inwards in a radial direction of the cowl and near the introduction port of the cowl, and the inlet is provided inwards in the radial direction of the cowl and between the outlet and the compressor blade in an axial line direction.

An aerodynamic element includes at least one first, fixed aerodynamic part including a box section that is covered at least partly by a plate with an extreme part, and one second aerodynamic part including a peripheral surface with an end and at least one holding element provided with a shoulder which forms, with the extreme part of the plate, a groove in which the end of the peripheral surface can be housed, such that the peripheral surface and the plate form a junction having an ascending profile. The presence of the groove makes it possible to obtain a continuous ascending junction with favors a laminar airstream on the upper surface of the aerodynamic element.

A slat arrangement for a wing of an aircraft. The arrangement has a movable leading-edge slat and a connection section. The leading-edge slat includes a slat leading edge and a slat trailing edge. The connection section includes a receiving opening for receiving the slat trailing edge. The connection section includes an overhang having a free end. The slat trailing edge is configured to be translated under the overhang. A trailing region of the slat is configured to be elastically deformed by the overhang when the slat trailing edge is moved into the receiving opening.

A method of providing active flow control for an aircraft includes cooling a liquid coolant in a heat exchanger by circulating a cooling airflow through the heat exchanger, and providing fluid communication between the cooling airflow and a boundary layer flow of at least one flight control surface of the aircraft. The cooling airflow affects the boundary layer flow of the flight control surface(s) to provide active flow control. A method of cooling an engine core of an engine assembly includes circulating a cooling fluid through the engine core, and cooling the cooling fluid with a cooling airflow used to provide active flow control to a flight control surface of the aircraft. An active flow control system for an aircraft is also discussed.