Abstract: A turbine installation comprising a turbine in combination with an electrical closed-loop control system. The turbine is disposed in a flow of water for producing electrical energy. The turbine includes a hollow hub and a plurality of runner blades pivotally connected to a hollow hub. Each blade comprises a hydrofoil being bounded by an inner surface and a distal outer surface, a leading edge and a trailing edge separated by a water directing surface. The blades are adjustable in pitch from a maximum pitch position in which an inner portion of the water directing surface extends substantially in a direction of the water flow, to a minimum pitch position in which an outer portion of the water directing surface is substantially perpendicular to the water flow. The hollow hub has spaced apart inner and outer surfaces and a hub longitudinal axis. Each blade is pivotally connected to the hub about a rotational axis.

Abstract: A turbine disposed in a water passageway includes a hub and associated runner blades. Each blade comprises an inner edge and a distal outer edge, a leading edge and a trailing edge separated by a water directing surface. Each blade is rotatable relative to the hub about a blade rotational axis. The water passageway includes a spherically-shaped discharge ring that conforms to the outer edges of the blades to improve certain turbine parameters such as cavitation, efficiency, flow disturbance, and fish survivability. The turbine hub may also include a spherically-shaped outer surface in a region swept by the inner edges of the blades when the blades are rotated from maximum to minimum pitch, as well as seals attached to the inner edges of the blades. The hub may also be associated with blades in which the chord is reduced in the root region of the blade.

Abstract: A method of assembling a turbine runner while it remains situated in a water passageway. The turbine runner comprises a hub having a longitudinal axis, spaced apart outer and inner surfaces defining a cavity, and a corresponding plurality of blades pivotally connected to the hub. Each blade has a trunnion and is supported in rotation by an associated blade support assembly including at least one trunnion bushing. The cavity substantially encloses the support assemblies. The method comprises the steps of assembling a maintenance platform in the water passageway below the runner, installing for at least one of the blades a new trunnion bushing in the associated blade support assembly, and removing the maintenance platform from the water passageway. The hub has an inner hub for supporting the trunnion bushing, and the inner hub may be split into upper and lower inner hubs which may be uncoupled for installing the new trunnion bushing.

Abstract: A turbine, disposed in water flowing therethrough, includes a hub and associated runner blades. Each blade comprises an inner surface and a distal outer surface, a leading edge and a trailing edge separated by a water directing surface. Each blade is rotatable relative to the hub about a blade rotational axis. The hub includes a spherically-shaped outer surface in a region of the hub swept by the inner surface of the blades when the blades are rotated from maximum to minimum pitch. The hub may also be associated with blades in which the chord is reduced in the root region of the blade. The turbine may also include seals attached to the blade inner surface and an essentially spherically-shaped discharge ring to improve certain turbine parameters such as cavitation, efficiency, flow disturbance, and fish survivability.