An example of a deflected slip stream wing system with coflow jet flow control includes a wingbox, a flap, a compressor, and a propulsor. The wingbox has a root and a tip. The flap is moveably attached to the wingbox and has a leading edge, a trailing edge, an injection opening, a suction opening, and a channel. The injection opening is disposed between the leading edge and the suction opening. The suction opening is disposed between the injection opening and the trailing edge. The channel extends from the injection opening to the suction opening. The compressor is disposed within the channel. The propulsor is disposed on the wingbox between the root and the tip. The propulsor has an off state and an on state. When in the on state, the propulsor is aligned relative to the flap such that fluid accelerated by the propulsor contacts the flap.

The fluid-dynamic structure comprises a fluid-dynamic exterior having a flow-augmented surface and a passive drag reduction system comprising a flow-repositioning duct having an inlet and an outlet that extend through the fluid-dynamic exterior. Under operative conditions, the passive drag reduction system is configured to direct a captured fluid stream into the inlet, through the flow-repositioning duct, and out of the outlet as a buffering fluid stream that flows along the flow-augmented surface. The inlet and the outlet are conformed and/or positioned such that, under the operative conditions, a total pressure at the inlet is greater than a total pressure at the outlet. The methods comprise flowing a bulk fluid stream across the fluid-dynamic exterior, establishing a pressure differential between the inlet and the outlet, and directing the captured fluid stream into the inlet and out of the outlet to flow along the flow-augmented surface as the buffering fluid stream.

A semi-active system for providing a required fluid flow, the system comprising an outlet configured to protrude into the main flow direction of an external fluid flow external to the semi-active system, an exhaust channel provided, in relation to the main flow direction of the external fluid flow, beneath the outlet, the exhaust channel being configured to inject an exhaust fluid flow into the external fluid flow, a device configured to produce a jet fluid flow and a pipe provided within the exhaust channel, the pipe being configured to fluid-communicatively couple to the device, and entrain, by the produced jet fluid flow, the exhaust fluid flow.

Air acceleration at slot of aircraft wing. In one embodiment, a wing includes an air duct configured to transport air in a spanwise direction along a leading edge of the wing from an air supply source of the aircraft. The wing further includes a discharge duct configured to transport the air in an aft direction from the air duct to an aft end of the wing, and one or more nozzles disposed on the aft end of the wing and configured to accelerate air into a slot between the wing and a flap of the aircraft to increase lift and reduce drag for the wing.

An aircraft and a control system for the aircraft includes a tilt-wing defining an inlet configured to receive air and an outlet in fluid communication with the inlet such that the outlet is configured to expel the air. The control system includes a high-lift device coupled to at least one of a leading edge, and a trailing edge of the tilt-wing. The high-lift device is movable relative to the tilt-wing. The control system includes a compressor in fluid communication with the inlet and the outlet. The compressor is configured to increase pressure of the air that is expelled out of the outlet. The outlet directs the pressurized air toward at least one of the high-lift device and a center section of the tilt-wing to maintain attachment of airflow across the tilt-wing. A method of operating the control system of the aircraft occurs to maintain attachment of airflow across the tilt-wing.

Disclosed are methods and apparatuses for mitigating the formation of concentrated wake vortex structures generated from lifting or thrust-generating bodies and maneuvering control surfaces wherein the use of contour surface geometries promotes vortex-mixing of high and low flow fluids. The methods and apparatuses can be combined with various drag reduction techniques, such as the use of riblets of various types and/or compliant surfaces (passive and active). Such combinations form unique structures for various fluid dynamic control applications to suppress transiently growing forms of boundary layer disturbances in a manner that significantly improves performance and has improved control dynamics.

Fluid systems are described herein. An example embodiment of a fluid system has a lengthwise axis, a chord length, a first body portion, a second body portion, a spacer, and a fluid pressurizer. The first body portion and the second body portion cooperatively define an injection opening, a suction opening, and a channel that extends from the injection opening to the suction opening. The fluid pressurizer is disposed within the channel cooperatively defined by the first body portion and the second body portion. The first body portion defines a cavity that is sized and configured to filter debris that enters the channel during use and provide a mechanism for removing the debris from the system.

Fluid systems are described herein. An example embodiment of a fluid system has a lengthwise axis, a chord length, a first body portion, a second body portion, a spacer, and a fluid pressurizer. The first body portion and the second body portion cooperatively define an injection opening, a suction opening, and a channel that extends from the injection opening to the suction opening. The fluid pressurizer is disposed within the channel cooperatively defined by the first body portion and the second body portion. The first body portion defines a cavity that is sized and configured to filter debris that enters the channel during use and provide a mechanism for removing the debris from the system.

A low drag surface is provided for a fluid washed object, the low drag surface comprising an aerodynamic surface comprising a cut-out region, and a continuously translatable surface comprising a surface portion. The surface portion is positioned in the cut-out region such that the aerodynamic surface and the surface portion form a fluidwash surface, and the surface portion is translatable relative to the aerodynamic surface.

Technologies are described herein for a drag recovery scheme using a boundary layer bypass duct system. In some examples, boundary layer air is routed around the intake of one or more of the engines and reintroduced aft of the engine fan in the nozzle duct in a mixer-ejector scheme. Mixer-ejectors mix the boundary layer flow to increase mass flow.