PatentDOI
Control of laminar flow in fluids by means of acoustic energy
TLDR
In this paper, the authors proposed to reduce the point of transition from laminar flow to turbulent flow in aerodynamic boundary layers on the surfaces of aircraft by radiating acoustic energy at frequencies greater than twice the critical TollmeinSchlichting frequency into the boundary layer.Abstract:
Retarding of the point of transition from laminar flow to turbulent flow in aerodynamic boundary layers on the surfaces of aircraft is accomplished by radiating acoustic energy at frequencies greater than twice the critical Tollmein-Schlichting frequency into the boundary layer. The acoustic energy interferes with the formation of Tollmein-Schlichting waves, thereby increasing the incidence of laminar flow and reducing aerodynamic drag.read more
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Journal ArticleDOI
The control of flow separation by periodic excitation
TL;DR: In this article, a review of the control of flow separation from solid surfaces by periodic excitation is presented, with an emphasis on experimentation relating to hydrodynamic excitation, although acoustic methods as well as traditional boundary layer control, such as steady blowing and suction are discussed in order to provide an appropriate historical context for recent developments.
Patent
Method and apparatus for structural integrity monitoring
TL;DR: In this article, a system for monitoring a structure and detecting disturbances and faults associated with such a structure is described, which includes an actuation device for mechanically exciting the structure and a sensing device for transducing vibrations experienced by the structure, and digital signal processing means for processing signals output by the sensing device.
Patent
Synthetic jet actuator and applications thereof
TL;DR: In this paper, a flexible metallized diaphragm forms a wall of the housing and can change the volume of the chamber when moved, and an electrical bias is imposed between the metallization and the electrode by a control system.
Patent
Synthetic jet actuators for cooling heated bodies and environments
Ari Glezer,Mark G. Allen +1 more
TL;DR: In this article, a synthetic jet actuator is used to generate a cyclical flow of the fluid jet, along the heated body and about a heat sink surface, which is then rejected to the ambient where it mixes and cools down.
PatentDOI
Intracanal prosthesis for hearing evaluation
Adnan Shennib,Richard C. Urso +1 more
TL;DR: A hearing evaluation and hearing aid fitting system as mentioned in this paper provides a fully immersed, three-dimensional acoustic environment to evaluate unaided, simulated aided, and aided hearing function of an individual.
References
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Patent
Method of and apparatus for controlling the boundary layer flow over the surface of a body
TL;DR: In this paper, a sensor element in the surface measures certain flow values in the boundary layer, conveyed to an analyzer control circuit which, in turn, conveys a signal to an active vibration transmitter in the body for providing the required control.
Patent
Low drag surface construction
TL;DR: In this article, a low-drag surface construction using a plurality of longitudinally extending, parallel, spaced apart linear vortices extending transversely of the free stream is proposed.
Patent
Acoustic wing stall delaying device
TL;DR: In this article, the authors propose an apparatus for delaying the onset of wing stall in an aircraft having a plurality of acoustic resonators positioned in the forward portion of the upper surface of the wing with a movable panel to close the resonator cavities during normal flight.
Patent
Method and device for influencing the flow on aerodynamic profiles
Abstract: In order to increase the lift of an aerodynamic profile and in order to reduce its drag, the flow close to the surface is set in oscillation with the aid of oscillation exciters (3) in order to generate local profile changes, pressure fluctuations and flow accelerations The oscillation exciters (3) are in this case connected to a part (4) of the surface of the aerodynamic profile (2)