Fluid flow driven engine

A reversible fluid flow driven engine comprising:

• (a) a base;
• (b) a pair of rotors rotably mounted on said base for selective rotation in opposite directions depending upon the direction of fluid flow, said rotors each comprising a cylindrical drum mounting a plurality of circumferentially spaced impellers projecting radially outward from said drum, said rotors being mounted in side-by-side spaced relation to define a fluid flow passageway between said drums;
• (c) a housing mounted on said base so as to surround said rotors, said housing having opposing outer peripheral walls terminating at their opposite ends in identical pairs of inwardly directed planar wall surfaces defining inwardly tapered passages communicating at their inner ends with the opposite ends of said passageway, said housing having an inner semi-cylindrical peripheral walls partially surrounding said rotors, said semi-cylindrical inner peripheral walls extending between the inner ends of the inwardly direction wall surfaces at one end of said opposing outer peripheral walls to the corresponding inner ends of the inwardly directed wall surfaces at the opposite end of said outer peripheral walls;
• (d) planar extension plates slidably mounted on said pairs of inwardly directed walls for movement in parallel relation thereto, said extension plates being displaceable inwardly beyond the innermost ends of said inwardly directed walls so as to vary the width of said passages at their innermost ends and thereby vary the velocity of a fluid flowing into said passageway;
• (e) actuating means for selectively extending said pairs of extension plates beyond the innermost ends of said inwardly directed walls;
• (f) reversible drive means for operatively connected said rotors to an energy generating system;
• and
• (g) said drums having a radius at least twice the width of said impellers, and the width of said passages at their outermost ends being at least three times greater than the smallest distance between said drums.