A combustion system includes at least one plasma actuator disposed along a substrate at a plasma location, and at least one fuel injector disposed along the substrate at an injection location. The fuel injector disperses fuel toward the plasma location. The plasma from plasma actuator ignites fuel from the fuel injector proximate the plasma location.

The aerodynamic element includes an ionization system which ionizes flow of air flowing over the top face of the aerodynamic element and a control system which generates at least one electromagnetic force associated with an electrical current and a magnetic field, the at least one electromagnetic force being oriented in the direction opposite to that of the flow of the ionized air flow such that the electromagnetic force reduces the instabilities of the flow of the airflow.

A method and system delay the laminar-to-turbulent transition of a supersonic or hypersonic boundary layer flow moving in a flow direction over a surface. For supersonic boundary layer flow, oblique first-mode instability waves present in the boundary layer and propagating at an oblique angle relative to the flow direction cause a laminar-to-turbulent transition in the boundary layer flow. These instability waves have a wavelength associated therewith in a direction perpendicular to the flow direction. Flow disruptors are used to generate modulations within the boundary layer flow wherein a wavelength of the modulations along the direction perpendicular to the flow direction is less than one-half of the wavelength of the instability waves. For hypersonic boundary layer flow, the flow disruptors generate modulations within the boundary layer flow wherein the wavelength of the modulations is less than streak spacing for optimal transient growth or, equivalently, in the range of one to two times the boundary layer thickness.

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.

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.

This patent provides for a method and apparatus 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 method and apparatus 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.

A free-streamline airfoil includes a front portion, the front portion including a leading edge geometry configured to force a sudden separation of the flow, and a contoured

A multilayered active surface is presented whose rugosity can be controlled by an applied electrical field. Varying the applied electrical field can control the rugosity of the surface which makes contact with a fluid, and thereby can affect instabilities of the boundary layer. A middle layer of the multilayered active surface can be made of a compliant electroactive material. In some cases, a pre-stretch in the middle layer can predefine a rugosity of the multilayered active surface without an applied electrical field, in which case an applied electrical field can further alter the rugosity in both amplitude and spatial periodicity and ultimately result to a smooth surface for a higher value of the applied electrical field. A top layer and a bottom layer are constructed using conductive material and uses as electrodes coupled to a voltage source to generate the electric field that controls the rugosity of the surface.

An aircraft includes a first leading edge defining the forward edge of a left aircraft wing, a second leading edge defining the forward edge of a right aircraft wing, a plurality of plasma actuators disposed along the first and second leading edges, a control processing unit communicatively coupled to each plasma actuator, and at least one flight stability sensor communicatively coupled to the control processing unit. The control processing unit commands at least one plasma actuator to generate plasma in response to a signal from the flight stability sensor.

A combustion system includes at least one plasma actuator disposed along a substrate at a plasma location, and at least one fuel injector disposed along the substrate at an injection location. The fuel injector disperses fuel toward the plasma location. The plasma from plasma actuator ignites fuel from the fuel injector proximate the plasma location.