초록 ▼

There is disclosed a method and apparatus for converting the kinetic energy of a moving fluid stream into useful work by means of a cascade of thin airfoils positioned therein. In one embodiment, the airfoils are provided with at least two degrees of freedom and adjacent airfoils are movable out of

There is disclosed a method and apparatus for converting the kinetic energy of a moving fluid stream into useful work by means of a cascade of thin airfoils positioned therein. In one embodiment, the airfoils are provided with at least two degrees of freedom and adjacent airfoils are movable out of phase. The airfoils are subjected to the aerodynamically induced oscillations caused by the aeroelastic phenomenon known as flutter and the oscillatory movement is then harnessed to do useful work. In an alternate embodiment, a cascade of airfoils is mechanically oscillated within a moving fluid stream to increase the propulsion of the fluid. Where the fluid is a liquid, the cascade includes a plurality of hydrofoils.

대표청구항 ▼

A method for converting the kinetic energy of a fluid stream into useful work comprising the steps of positioning a device including a cascade of thin airfoils in a moving fluid stream to define an aerodynamic system wherein the airfoils are at zero angle of attack when undisturbed and are provided

A method for converting the kinetic energy of a fluid stream into useful work comprising the steps of positioning a device including a cascade of thin airfoils in a moving fluid stream to define an aerodynamic system wherein the airfoils are at zero angle of attack when undisturbed and are provided with at least two degrees of freedom and wherein adjacent airfoils are movable out of phase, adjusting the system until the velocity of the fluid stream is a critical velocity for the system sufficient to induce flutter oscillations, disturbing at least one of the airfoils, and then utilizing the resultant oscillations to produce useful work.