Abstract: Inventive systems (e.g., turbines) for harnessing hydroelectric energy are described. The turbines include: (1) a central longitudinal shaft configured to mount and to rotate on a central axis perpendicular to a direction of fluid flow; (2) a plurality of substantially circularly arcing blades designed to couple to the shaft, each of the substantially circularly arcing blades having defined at one end one or more blade apertures; and (3) a fastening sub-assembly including fasteners, the fastening sub-assembly used for coupling the circularly arcing blades to the shaft.

Abstract: A generally spherical turbine configured to rotate transversely within a cylindrical pipe under the power of fluid flowing either direction therethrough is operatively coupled with a rotating machine or generator to produce electricity. In one embodiment, the blades of the spherical turbine curve in an approximately 180 degree arc in a plane that is at an inclined angle relative to the rotational axis of a central shaft. In another embodiment, a deflector is provided upstream of the spherical turbine and within the cylindrical pipe to control flow through the spherical turbine by shielding a part thereof. The blades of the spherical turbine are airfoil in cross section to optimize hydrodynamic flow, to minimize cavitation, and to maximize conversion from axial to rotating energy.

Abstract: A generally spherical turbine configured to rotate transversely within a cylindrical pipe under the power of fluid flowing either direction therethrough is operatively coupled with a rotating machine or generator to produce electricity. In one embodiment, the blades of the spherical turbine curve in an approximately 180 degree arc in a plane that is at an inclined angle relative to the rotational axis of a central shaft. In another embodiment, a deflector is provided upstream of the spherical turbine and within the cylindrical pipe to control flow through the spherical turbine by shielding a part thereof. The blades of the spherical turbine are airfoil in cross section to optimize hydrodynamic flow, to minimize cavitation, and to maximize conversion from axial to rotating energy.

Abstract: A generally spherical turbine configured to rotate transversely within a cylindrical pipe under the power of fluid flowing either direction therethrough is operatively coupled with a rotating machine or generator to produce electricity. In one embodiment, the blades of the spherical turbine curve in an approximately 180 degree arc in a plane that is at an inclined angle relative to the rotational axis of a central shaft. In another embodiment, a deflector is provided upstream of the spherical turbine and within the cylindrical pipe to control flow through the spherical turbine by shielding a part thereof. The blades of the spherical turbine are airfoil in cross section to optimize hydrodynamic flow, to minimize cavitation, and to maximize conversion from axial to rotating energy.

Abstract: A helical turbine configured to rotate transversely within a cylindrical pipe under the power of fluid flowing either direction therethrough is operatively coupled with a rotating machine or generator to produce work or electricity. The twisted blades of the turbine define a right circular cylinder when the shaft mounting them rotates under the influence of fluid flow through the pipe. In one embodiment, baffles are provided at least upstream of the cylindrical turbine and within the cylindrical pipe to control flow through the cylindrical turbine. The twisted blades of the helical turbine are airfoil in cross section, as are the radial struts or spokes that mount the twisted blades to the rotatable shaft, thereby to optimize hydrodynamic flow, to minimize cavitation, and to maximize conversion from axial to rotating energy.