Abstract:
A method to manipulate boundary layer conditions within a ducted fluid flow is provided. This method may be used to attach fluid flow to ducted surfaces bounding the fluid flow. This involves flowing a fluid over the surface wherein the fluid contains positively charged ions and electrons. An electric field accelerates ions and electrons in directions parallel to the electric field. The accelerated positively charged ions accelerate low energy air within lower regions of a boundary layer over the ducted surfaces bounding the ducted fluid flow. A magnetic field at the surface redirects ions and electrons based on their velocity and charge. The magnetic field imparts little force on the relatively heavy and slow moving positive ions but has a significant impact on the relatively fast moving, light weight electrons
Abstract:
A method to manipulate boundary layer conditions within a ducted fluid flow is provided. This method may be used to attach fluid flow to ducted surfaces bounding the fluid flow. This involves flowing a fluid over the surface wherein the fluid contains positively charged ions and electrons. An electric field accelerates ions and electrons in directions parallel to the electric field. The accelerated positively charged ions accelerate low energy air within lower regions of a boundary layer over the ducted surfaces bounding the ducted fluid flow. A magnetic field at the surface redirects ions and electrons based on their velocity and charge. The magnetic field imparts little force on the relatively heavy and slow moving positive ions but has a significant impact on the relatively fast moving, light weight electrons.
Abstract:
A plasma jet system includes a housing with a single opening. A plasma generator is coupled to ionize a fluid in the housing. An electromagnetic accelerator is coupled to generate an electric field that accelerates ionized fluid in the housing toward the opening. A controller can modulate the frequency of the electric field to cause the ionized fluid to form a plasma vortex flow through the opening. A magnetic field is applied normal to the direction of the plasma vortex flow to mitigate the momentum of the electrons. The electrons slowed by the magnetic field can be collected and conducted to a location where they are re-inserted into the plasma vortex flow to maintain charge neutrality.
Abstract:
An object moving through a fluid uses plasma to keep turbulent mixing vortices associated with turbulent air away from the majority of the surface of the object. The plasma may be used to enhance physical riblets, or the plasma may create a virtual riblet.
Abstract:
A cross flow instability inhibiting assembly generates periodic aerodynamic disturbances on a swept wing. The cross flow instability inhibiting assembly is dynamic in that it can be selectively turned on and off as needed. The cross flow instability inhibiting assembly is a strip of material separating a set of electrodes from a set of electrodes. When energized, the fields created between the electrodes and electrodes create plasma disturbances around the electrodes. The electric fields and plasma create heating and body force disturbances on the air or surrounding fluid. These plasma generated disturbances disrupt development of unstable voriticity due to cross flow, inhibiting transition to turbulent flow of the wing to which it is attached. The electrodes may be connected to electrical power in series or they may be connected to an alternating configuration. The system allows for various uses based on the design of the wing and the conditions in which the host aircraft is flying.
Abstract:
A plasma-actuated vortex generator arrangement includes a plurality of spaced-apart vortex generators, and a plasma actuator distributed amongst the plurality of vortex generators.
Abstract:
A method to manipulate a fluid flow over a surface is provided. This method may be used to reduce drag, improve the lift to drag (L/D) ratio, attach fluid flow, or reduce flow noise at the surface. This involves flowing a fluid over the surface wherein the fluid contains positively charged ions and electrons. An electric field accelerates ions and electrons in directions parallel to the electric field. A magnetic field at the surface redirects ions and electrons based on their velocity and charge. The magnetic field imparts little force on the relatively heavy and slow moving positive ions but has a significant impact on the relatively fast moving, light weight electrons. This results in a non-zero net change in the total momentum of the positive ions and electrons allowing thrust to be realized. This thrust may be sufficient for vehicle propulsion or manipulation of the fluid flow around the vehicle. Pulsed and traveling wave implementations of this body force enable exploitation of frequencies to which the flow is sensitive, improving effectiveness of this method.
Abstract:
A wing for an aircraft has a passive jet spoiler for providing yaw control by increasing drag on the wing. The spoiler comprises an inlet located near the leading edge of a lower surface of the wing and at least one outlet formed on the lower surface or on an upper surface of the wing. An internal passage connects the inlet and each outlet for allowing air to pass from the inlet to the outlet. The air exits the outlets generally normal to the respective surface of the wing, causing a laminar flow to separate from the surfaces downstream of each outlet. The separated flow increases the drag on the wing, producing a yawing moment on the aircraft. Selective placement of the outlets on the upper and lower surfaces limits undesirable roll and pitch moments. Valves are provided for selectively controlling the amount of air passing through the spoiler.
Abstract:
A method of de-saturating a control moment gyroscope that leverages a torque on an aircraft that is generated by airflow over the aircraft. As an aircraft navigates through an airspace, the aircraft may destabilize and reorient to form a sideslip angle that forms the airflow torque on the aircraft. The control moment gyroscope may be de-saturated into a neutral position that in turn exerts a torque on the aircraft that counters the airflow torque. A scissor pair of first and second control moment gyroscopes can be used for generating a torque in a single plane.
Abstract:
A plasma jet system includes a housing with a single opening. A plasma generator is coupled to ionize a fluid in the housing. An electromagnetic accelerator is coupled to generate an electric field that accelerates ionized fluid in the housing toward the opening. A controller can modulate the frequency of the electric field to cause the ionized fluid to form a plasma vortex flow through the opening. A magnetic field is applied normal to the direction of the plasma vortex flow to mitigate the momentum of the electrons. The electrons slowed by the magnetic field can be collected and conducted to a location where they are re-inserted into the plasma vortex flow to maintain charge neutrality.