Method and System of Extracting Energy from Wind

A system comprising:

• a structure that defines an elongated cavity that has a first resonant frequency;
• an entrance portion of the elongated cavity that defines an aperture, the entrance portion defines a central axis, two points on opposite sides of the aperture define a line segment, and the line segment intersects the central axis at a non-right angle;
• and
• a resonant structure configured to mechanically oscillate at the first resonant frequency, the resonant structure fluidly coupled to the elongated cavity, and wherein pressure waves in the elongated cavity cause the resonant structure to oscillate.

A method of generating electrical energy from wind comprising:

• directing air flow across an aperture of an elongated cavity that has a resonant frequency, an entrance portion of the elongated cavity defines a central axis, and the acute angle between the central axis and the direction of air flow is between 10 and 50 degrees inclusive;
• creating pressure waves within the elongated cavity at least in part by vortices within air flow across the aperture, and a frequency at which vortices are created substantially the same as the resonant frequency of the elongated cavity;
• exciting a resonant structure by way of the pressure waves within the elongated cavity, the resonant structure configured to resonate substantially at the resonant frequency;
• and
• generating electrical energy from oscillatory motion of the resonant structure.

A system to extract electrical energy from wind comprising:

• a structure that defines an elongated cavity that has a first resonant frequency;
• an entrance portion of the elongated cavity that defines an aperture, and air flow is directed across the aperture, the entrance portion defines a central axis and the acute angle between the central axis and the direction of air flow is between 10 and 50 degrees inclusive;
• a resonant structure configured to mechanically oscillate at the first resonant frequency, the resonant structure fluidly coupled to the elongated cavity;
• and
• an electrical generator mechanically coupled to the resonant structure;
• wherein pressure waves within the elongated cavity caused by the vortex shedding across the aperture cause the resonant structure to mechanically oscillate, and wherein the electrical generate creates electrical energy from the mechanical oscillation.