2821results about "Air-flow influencers" patented technology

An article having low wettability is presented. The article comprises a body portion and a surface portion disposed on the body portion. The surface portion comprises a plurality of features disposed on the body portion, and the features have a size, shape, and orientation selected such that the surface portion has a wettability sufficient to generate, with a reference liquid, a contact angle of at least about 100 degrees. The features comprise a height dimension (h) and a width dimension (a), and are disposed in a spaced-apart relationship characterized by a spacing dimension (b). The ratio of b/a and the ratio of h/a are such that the drop exhibits metastable non-Wenzel behavior.

A single dielectric barrier aerodynamic plasma actuator apparatus based on the dielectric barrier discharge phenomenon is disclosed and suggested for application to aerodynamic uses for drag reduction, stall elimination and airfoil efficiency improvement. In the plasma actuator apparatus non-uniform in time and space, partially ionized gasses are generated by one or more electrode pairs each having one electrically encapsulated electrode and one air stream exposed electrode and energization by a high-voltage alternating current waveform. The influence of electrical waveform variation, electrode polarity, electrode size and electrode shape on the achieved plasma are considered along with theoretical verification of achieved results. Light output, generated thrust, ionizing current waveform and magnitude and other variables are considered. Misconceptions prevailing in the present day plasma generation art are addressed and are believed-to-be corrected. The influence of electrostatic shielding effects of the developed plasma on the applied electric field are also considered.

A vehicle, particularly a VTOL air vehicle, includes a duct carried by the vehicle frame with the longitudinal axis of the duct perpendicular to the longitudinal axis of the vehicle frame; a propeller rotatably mounted within the duct about the longitudinal axis of the duct to force an ambient fluid, e.g. air, therethrough from its inlet at the upper end of the duct through its exit at the lower end of the duct, and thereby to produce an upward lift force applied to the vehicle; and a plurality of parallel, spaced vanes pivotally mounted to and across the inlet end of the duct about pivotal axes perpendicular to the longitudinal axis of the duct and substantially parallel to the longitudinal axis of the vehicle frame. The vanes are selectively pivotal to produce a desired horizontal force component to the lift force applied to the vehicle. Various vane arrangements are disclosed for producing side, roll, pitch and yaw movements of the vehicle.

A system receives information regarding current flight conditions of a device such as an aircraft and determines the acoustic level of the sonic boom and/or other noise generated by the device during operation. The current acoustic level is compared to a desired level, and various cues are displayed to operators regarding corrective actions that can be taken to reduce or maintain the acoustic level at the desired level. The system also predicts future acoustic levels based on current operating conditions, and varies the urgency of the cues based on whether and how quickly the device will exceed the desired acoustic level. Options to limit maneuvers and to automatically adjust operating condition parameters can be enabled. Options to display additional information regarding past, current, and predicted acoustic levels can also be selected. Signals that can be used to automatically control the acoustic level of a device during operation can also be generated for use in devices that can operate autonomously.

A vehicle including a fuselage having a longitudinal axis and a transverse axis, two Ducted Fan lift-producing propellers carried by the fuselage on each side of the transverse axis, a pilot's compartment formed in the fuselage between the lift-producing propellers and substantially aligned with one side of the fuselage, a payload bay formed in the fuselage between the lift-producing propellers and opposite the pilot's compartment, and two pusher fans located at the rear of the vehicle. Many variations are described enabling the vehicle to be used not only as a VTOL vehicle, but also as a multi-function utility vehicle for performing many diverse functions including hovercraft and ATV functions. Also described is an Unmanned version of the vehicle. Also described are unique features applicable in any single or multiple ducted fans and VTOL vehicles.

Morphing an aerodynamic body's geometry in situ can optimize its aerodynamic properties, increasing range, reducing fuel consumption, and improving many performance parameters. The aerodynamic load exerted on the body by the flow is one such parameter, typically characterized as lift or drag. It is the aim of the present disclosure to teach the use of passive adaptive morphing structures to manage these aerodynamic loads.

The present invention is directed to the manufacture of and the use of an aerodynamic flow control device having a compact array of a plurality of fluidic actuators in planar, curved, circular and annular configurations. The compact array of fluidic actuators of the invention may be designed to produce oscillating or pulsed jets at the exit ports with frequencies in the range of 1-22 kHz. They may be integrally manufactured along with the wing sections, flaps, tail and rudder of airplane, the inlet or exit geometries of a jet engine. When supplied with a source of fluid such as air, these arrays of actuators produce a set of fluid jets of random phase of high velocity and influence the main stream of air over the subject surface. The beneficial effects of modifying flow using the present invention include increased lift, reduced drag, improved performance and noise reduction in jet engines.

The present invention discloses systems and methods for the performance enhancement of rotary wing aircraft through reduced torque, noise and vibration. In one embodiment, a system includes a sail having an aerodynamic shape positioned proximate to a tip of the rotor blade. An actuator may be configured to rotate the sail relative to the blade tip. a A control system receives information from a rotorcraft system and commands the actuator to rotate the sail to a predetermined favorable rotor blade operating condition. In another embodiment, a method includes configuring the rotorcraft in a selected flight condition, communicating input signals to a control system operable to position sails coupled to tips of blades of a rotor assembly, processing the input signals according to a constraint condition to generate sail positional information, and transferring the sail positional information to the sail.

A system and method for controlling boundary layer flow over an aircraft wing are provided. The system includes at least one wing element, and a plurality of ports defined in the wing element and in fluid communication with one another. The system also includes at least one fluidic device operable to continuously ingest the fluid through at least one of the ports and eject the fluid out of at least one other port to control boundary layer flow of the fluid over the wing element.

An airflow control device comprises a body and an active material in operative communication with the body. The active material, such as a shape memory material, is operative to change at least one attribute in response to an activation signal. The active material can change its shape, dimensions and/or stiffness producing a change in at least one feature of the airflow control device such as shape, dimension, location, orientation, and/or stiffness to control vehicle airflow to better suit changes in driving conditions such as the need for increased airflow through the radiator due to increases in engine coolant temperature. As such, the device improves vehicle fuel economy while maintaining proper engine cooling. An activation device, controller and sensors may be employed to further control the change in at least one feature of the airflow control device such as shape, dimension, location, orientation, and/or stiffness of the device. A method for controlling vehicle airflow selectively introduces an activation signal to initiate a change of at least one feature of the device that can be reversed upon discontinuation of the activation signal.

Embodiments of the invention relate to a vane assembly formed by a forward airfoil segment and an aft airfoil segment. The aft segment is made of metal and can define the trailing edge of the vane assembly. The forward segment can be made of ceramic, CMC or metal. The forward and aft segments cannot be directly joined to each other because of differences in their rates of thermal expansion and contraction. The forward and aft segments can be positioned substantially proximate to each other so as to form a gap therebetween. In one embodiment, the gap can be substantially sealed by providing a coupling insert or leaf springs in the gap. A separate metal aft segment can take advantage of the beneficial thermal properties of the metal to improve cooling efficiency at the trailing edge without limiting the rest of the vane to being made out of metal.

A leading edge structure for an aerodynamic surface includes a support structure made of fiber-reinforced synthetic material and a skin structure made of metal mounted on the support structure. The support structure includes an inner laminate, an outer laminate, and longitudinally extending tubes and channels arranged between the inner and outer laminates, as well as a synthetic foam filler material in the spaces between the tubes, channels, and laminates. The skin structure includes an outer skin having perforations, especially in the form of suction holes, an inner skin, and spacer members interconnected therebetween so as to form a substantially form-stable metal skin structure. Respective holes pass through the inner skin, the outer laminate, and the walls of the tubes and channels in order to communicate the suction hole perforations of the outer skin with the interior spaces within the tubes and channels. The skin structure is adhesively bonded to the support structure. In a method for making the leading edge structure, the prefabricated components of the support structure are laid up, molded and cured in a positive mold, the prefabricated components of the skin structure are formed and soldered together on a positive mold, and then the skin structure is adhesively bonded onto the support structure.

In one aspect the present subject matter is directed to a gas-electric propulsion system for an aircraft. The system may include a turbofan jet engine, an electric powered boundary layer ingestion fan that is coupled to a fuselage portion of the aircraft aft of the turbofan jet engine, and an electric generator that is electronically coupled to the turbofan jet engine and to the boundary layer ingestion fan. The electric generator converts rotational energy from the turbofan jet engine to electrical energy and provides at least a portion of the electrical energy to the boundary layer ingestion fan. In another aspect of the present subject matter, a method for propelling an aircraft via the gas-electric propulsion system is disclosed.

A plasma fairing for reducing noise generated by, for example, an aircraft landing gear is disclosed. The plasma fairing includes at least one plasma generating device, such as a single dielectric barrier discharge plasma actuator, coupled to a body, such as an aircraft landing gear, and a power supply electrically coupled to the plasma generating device. When energized, the plasma generating device generates a plasma within a fluid flow and reduces body flow separation of the fluid flow over the surface of the body. In another example, the body includes a plurality of plasma generating devices mounted to the surface the body to further aid in noise reduction.

This invention solves the problem of reducing the fluid friction resistance accompanying relative movement of surfaces of a solid and a liquid. A superhydrophobic coating acting as a substrate for a gaseous lubricant of very low viscosity, reducing the fluid skin friction, has a hierarchic fracal structural of the surface wherein the forms of the first hierarchic level (2, 3, 9) are located at the coating's substrate, and the forms of each successive hierarchic level (22, 33, 99) are located on the surface of the previous hierarchic level and the forms of individual higher hierarchic levels reiterate the forms of the lower hierarchic levels. Forms of at least two hierarchic levels of rows (2, 22) and ridges (3, 33, 99) occur in the coating and, also, the surface has anisotropic geometry, maximally developed fractally in the direction transverse to the direction of flow and maximally smooth in the direction of flow and, also, has channels located in the coating's substrate to ensure gas flow.