Patent ID: 6622483
Filing Date: 2003-09-23
Classification: E02B,F03B,Y02E

Abstract:
An ocean wave energy extracting system, said system comprising:wave focusing means to magnify the periodic vertical peak to trough displacement of incoming waves at a predetermined plan location, wherein the wave focusing means comprises an open sided bay bounded by a generally upright wall, the wall being configured at its inner periphery to define in plan section from the bay opening two converging arms of generally part parabolic curvature, wherein the axes of symmetry of each of the paraboli from which the arms are derived are parallel and the arms are joined adjacent their converging ends to form a shared apex, the wall being oriented to admit an advancing wave front in a direction generally parallel to the axes of symmetry, so that upon reflection from the wall the wave converges to an energy harnessing region near the apex at or adjacent the focus of each of the paraboli, thereby amplifying the vertical displacement of the wave at that region; an air compression chamber having a generally submerged water inlet disposed at or closely adjacent said predetermined plan location to admit the periodically oscillating waves so as to displace a volume of the air there above to thereby generate a correspondingly periodic reversing air flow; the air compression chamber also having an air outlet; and an air driven turbine located in the air outlet and operable to rotate unidirectionally in response to the reversing air flow, the turbine operable to rotate unidirectionally when subjected to reversing generally axial fluid flow therethrough, the turbine including a rotor comprising: a central hub; and a plurality of straight radially extending aerofoil sectioned blades each connected with the hub; the cross-section of each of the blades being approximately symmetrical about a line defining the maximum camber height and generally constant along its radially extending length; wherein the approximately symmetrical shape of the blades and their orientation in relation to the hub facilitates unidirectional rotation of the rotor in response to reversing axial fluid flows therethrough.