Systems and methods are described herein to implement transverse momentum injection at low frequencies to directly modify large-scale eddies in a turbulent boundary layer on a surface of an object. A set of transverse momentum injection actuators may be positioned on the surface of the object to affect large-scale eddies in the turbulent boundary layer. The system may include a controller to selectively actuate the transverse momentum injection actuators with an actuation pattern to affect the large-scale eddies to modify the drag of the fluid flow on the surface. In various embodiments, the transverse momentum injection actuators may be operated at frequencies less than 10,000 Hertz.

A plasma plate is used to minimize drag of a fluid flow over an exposed surface. The plasma plate includes a series of plasma actuators positioned on the surface. Each plasma actuator is made of a dielectric separating a first electrode exposed to a fluid flow and a second electrode separated from the fluid flow under the dielectric. A pulsed direct current power supply provides a first voltage to the first electrode and a second voltage to the second electrode. The series of plasma actuators is operably connected to a bus which distribute powers and is positioned to minimize flow disturbances. The plasma actuators are arranged into a series of linear rows such that a velocity component is imparted to the fluid flow.

An assembly for arrangement to the surface of an aerodynamic profile comprises an array of actuators, which are designed as piezo actuators and plasma actuators.

An airflow separation detecting method includes: applying an alternating-current voltage having a predetermined voltage value to a plasma actuator, the plasma actuator being disposed on a part of a surface of an object; and detecting that separation, from the surface of the object, of an airflow flowing on the surface of the object is occurring, in a case where an absolute value of a temporal variation rate of an electric power consumption value of the plasma actuator or an absolute value of a temporal variation rate of a current value of the plasma actuator is equal to or greater than a predetermined value, the temporal variation rate being a rate of variation relative to time, the electric power consumption value or the current value of the plasma actuator being measured under application of the alternating-current voltage having the predetermined voltage value to the plasma actuator.

A plasma plate is used to minimize drag of a fluid flow over an exposed surface. The plasma plate includes a series of plasma actuators positioned on the surface. Each plasma actuator is made of a dielectric separating a first electrode exposed to a fluid flow and a second electrode separated from the fluid flow under the dielectric. A pulsed direct current power supply provides a first voltage to the first electrode and a second voltage to the second electrode. The series of plasma actuators is operably connected to a bus which distribute powers and is positioned to minimize flow disturbances. The plasma actuators are arranged into a series of linear rows such that a velocity component is imparted to the fluid flow.

A wing comprising a leading edge composed of a skin transparent to microwaves, magnetrons implanted under the skin and arranged in rows and in columns alongside one another, between two successive rows of magnetrons, a discharge row successively comprising an electrode and a ground electrode, where each electrode passes through the skin and where each ground electrode is under the skin.

Electroaerodynamic devices and their methods of operation are disclosed. In one embodiment, ions are formed by dielectric barrier discharge using a time varying voltage differential applied between a first electrode and a second electrode. The ions are then accelerated in a downstream direction using a second voltage differential applied between a third electrode and the first and/or second electrodes, where the third electrode is located down stream from the first and second electrodes. The ions may then collide with naturally charged molecules and/or atoms within a fluid to accelerate the fluid in the downstream to create an ionic wind and an associated thrust.

A method for active flow control of a fluid flow that flows along a flow surface includes generating a first local velocity field in the fluid flow by introducing a first vortex structure into the fluid flow by a first flow control actuator coupled to a first actuation site of the flow surface, and introducing a second vortex structure into the first local velocity field by a second flow control actuator coupled to a second actuation site of the flow surface located downstream of the first actuation site, when a head vortex of the first vortex structure has propagated with the fluid flow downstream the second actuation site.

An aircraft (5) including an aerodynamic surface (6), an aerodynamics improvement device with a first electrode (27) embedded beneath and electrically isolated from the aerodynamic surface (6), a second electrode (28) electrically isolated from the first electrode (27), a voltage generator (30) adapted to apply a voltage between the first and the second electrode, further comprising a layer of electrically insulating material (26) between the second electrode (28) and the aerodynamic surface (6). Methods for detecting ice on and de-icing an aerodynamic surface (6), and for delaying a boundary layer transition and separation from the aerodynamic surface.

An apparatus configured to reduce drag is provided. The apparatus includes a plasma actuator including a hollow cylinder with two open bases, a first electrode disposed inside the cylinder, a second electrode disposed outside the cylinder, and a plasma layer disposed inside the cylinder next to the first electrode, a surface including the plasma actuator disposed on the surface, and a motion actuator configured to move the plasma actuator in a sweeping motion across a face of the surface.