Hydro-turbine runner

A turbine installation including a water passageway extending from an upper elevation source of water to a lower elevation discharge region, the turbine installation comprising:

• a turbine disposed in the water passageway and including:
• a hollow hub having spaced apart inner and outer surfaces and a longitudinal axis;
• and
• a plurality of blades, each of the blades being pivotally connected to the hub about a rotational axis extending in a direction generally perpendicular to the longitudinal axis, each of the blades having an outer surface distal from an inner surface, a leading edge and a trailing edge separated by a water directing surface, each blade having a chordal distance defined by a distance taken along a perpendicular line extending from the rotational axis to the leading edge, the chordal distance of at least one of the blades being shortened in a root region of the leading edge proximate the hub thereby causing the blade inner surface to lie effectively in contact with the hub outer surface upstream of the blade rotational axis;
• wherein each of the blades is 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, and wherein the outer surface of the hub extending upstream of the blade rotational axis swept by the inner surfaces during rotation of the blades from the maximum pitch to the minimum pitch is spherically-shaped, and the inner surfaces oppositely facing the upstream outer surface substantially conform thereto thereby limiting a gap formed therebetween;
• and
• an electrical closed-loop control system for adjusting each blade in position from the maximum pitch to the minimum pitch, the control system including a digital based processor associated with sensors selectively generating electrical signals indicative of at least turbine speed, blade pitch, and difference in elevation between the upper elevation source of water and the lower elevation discharge region.

A turbine installation having a flow of water passing therethrough from an upper elevation source of water to a lower elevation discharge region, the turbine installation comprising:

• a turbine disposed in the flow of water and including:
• a hollow hub having spaced apart inner and outer surfaces and a longitudinal axis;
• and
• a plurality of blades, each of the blades being pivotally connected to the hub about a rotational axis, each of the blades having an outer surface distal from an inner surface, a leading edge and a trailing edge separated by a water directing surface each of the blades having a downstream chordal distance, being a distance taken along a perpendicular line extending from the rotational axis to the trailing edge, the chordal distance of at least one of the blades being shortened in a region of the trailing edge proximate the hub so that the blade inner surface lies effectively in contact with the hub outer surface downstream of the blade rotational axis;
• wherein each of the blades is 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, and wherein the outer surface of the hub extending downstream of the blade rotational axis swept by the inner surfaces during rotation of the blades from the maximum pitch to the minimum pitch is spherically-shaped, and the inner surfaces oppositely facing the downstream outer surface substantially conform thereto thereby limiting a gap formed therebetween;
• and
• an electrical closed-loop control system for adjusting each blade in position from the maximum pitch to the minimum pitch, the control system including a digital based processor associated with sensors selectively generating electrical signals indicative of at least turbine speed blade pitch, and difference in elevation between the upper elevation source of water and the lower elevation discharge region.

A hydroelectric turbine installation comprising:

• a water passageway for containing turbine components and extending from an upper elevation source of water to a lower elevation discharge region, the passageway including a plurality of wicket gates adjustable in position to control water flowing therethrough;
• a turbine comprising:
• a. a hollow hub having spaced apart inner and outer surfaces and a longitudinal axis, the hub being disposed in the passageway to produce electrical energy by rotation of the hub from the water flowing through the passageway;
• and
• b. a plurality of blades, each blade comprising 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, each blade being pivotally connected to the hub about a rotational axis extending in a direction generally perpendicular to the longitudinal axis so that its inner surface is proximate the hub;
• a discharge ring disposed in a region of the passageway proximate the rotational axes of the blades, the ring having a face oppositely facing the outer surface of the blades;
• and
• an electrical closed-loop control system for adjusting each blade in position from a maximum pitch position to a minimum pitch position, an outer portion of the water directing surface forming a greater impediment to the water flowing through the passageway in the minimum pitch position than in the maximum pitch position;
• wherein the outer surface of the hub swept by the inner surfaces of the blades during rotation of the blades from the maximum pitch to the minimum pitch is spherically-shaped, and wherein the inner surfaces of the blades substantially conform to the outer surface of the hub, thereby limiting gaps formed therebetween;
• and
• wherein each blade inner surface meets a respective water directing surface along an edge, the edge being rounded at least in a region of the inner surface extending from a respective leading edge.

A hydroelectric turbine installation comprising:

• a water passageway for containing turbine components and extending from an upper elevation source of water to a lower elevation discharge region, the passageway including a plurality of wicket gates adjustable in position to control water flowing therethrough;
• a turbine comprising:
• a. a hollow hub having spaced apart inner and outer surfaces and a longitudinal axis, the hub being disposed in the passageway to produce electrical energy by rotation of the hub from the water flowing through the passageway;
• b. a plurality of blades, each blade comprising 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, each blade being pivotally connected to the hub about a rotational axis extending in a direction generally perpendicular to the longitudinal axis so that its inner surface is proximate the hub;
• a discharge ring disposed in a region of the passageway proximate the rotational axes of the blades, the ring having a face oppositely facing the outer surface of the blades;
• and
• an electrical closed-loop control system for adjusting each blade in position from a maximum pitch position to a minimum pitch position, an outer portion of the water directing surface forming a greater impediment to the water flowing through the passageway in the minimum pitch position than in the maximum pitch position;
• wherein the outer surface of the hub swept by the inner surfaces of the blades during rotation of the blades from the maximum pitch to the minimum pitch is spherically-shaped, and wherein the inner surfaces of the blades substantially conform to the outer surface of the hub, thereby limiting gaps formed therebetween;
• wherein the control system comprises:
• a plurality of sensors, the sensors selectively generating electrical signals indicative of turbine speed, blade pitch, wicket gate position, and difference in elevation between the upper elevation source of water and the lower elevation discharge region;
• and
• an electrical controller receiving and processing the electrical signals from the sensors, the controller capable of generating signals for adjusting in position the blades and wicket gates.

A hydroelectric turbine installation comprising:

• a water passageway for containing turbine components and extending from an upper elevation source of water to a lower elevation discharge region, the passageway including a plurality of wicket gates adjustable in position to control water flowing therethrough;
• a turbine comprising:
• a. a hollow hub having spaced apart inner and outer surfaces and a longitudinal axis, the hub being disposed in the passageway to produce electrical energy by rotation of the hub from the water flowing through the passageway;
• b. a plurality of blades, each blade comprising 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, each blade being pivotally connected to the hub about a rotational axis extending in a direction generally perpendicular to the longitudinal axis so that its inner surface is proximate the hub;
• a discharge ring disposed in a region of the passageway proximate the rotational axes of the blades, the ring having a face oppositely facing the outer surface of the blades;
• an electrical closed-loop control system for adjusting each blade in position from a maximum pitch position to a minimum pitch position, an outer portion of the water directing surface forming a greater impediment to the water flowing through the passageway in the minimum pitch position than in the maximum pitch position;
• and
• a sensor generating an electrical signal indicative of density of fish present in the water:
• wherein the outer surface of the hub swept by the inner surfaces of the blades during rotation of the blades from the maximum pitch to the minimum pitch is spherically-shaped, and wherein the inner surfaces of the blades substantially conform to the outer surface of the hub, thereby limiting gaps formed therebetween.

A hydroelectric turbine installation comprising:

• a water passageway for containing turbine components and extending from an upper elevation source of water to a lower elevation discharge region, the passageway including a plurality of wicket gates adjustable in position to control water flowing therethrough;
• a turbine comprising:
• a. a hollow hub having spaced apart inner and outer surfaces and a longitudinal axis, the hub being disposed in the passageway to produce electrical energy by rotation of the hub from the water flowing through the passageway;
• b. a plurality of blades, each blade comprising 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, each blade being pivotally connected to the hub about a rotational axis extending in a direction generally perpendicular to the longitudinal axis so that its inner surface is proximate the hub;
• a discharge ring disposed in a region of the passageway proximate the rotational axes of the blades, the ring having a face oppositely facing the outer surface of the blades;
• and
• an electrical closed-loop control system for adjusting each blade in position from a maximum pitch position to a minimum pitch position, an outer portion of the water directing surface forming a greater impediment to the water flowing through the passageway in the minimum pitch position than in the maximum pitch position;
• wherein the outer surface of the hub swept by the inner surfaces of the blades during rotation of the blades from the maximum pitch to the minimum pitch is spherically-shaped, and wherein the inner surfaces of the blades substantially conform to the outer surface of the hub, thereby limiting gaps formed therebetween;
• and
• wherein the control system includes a digital-based processor controller associated with sensors selectively generating electrical signals indicative of at least turbine speed and blade pitch and difference in elevation between the upper elevation source of water and the lower elevation discharge region.

A method of improving at least one turbine characteristic of a group of characteristics comprising efficiency, flow turbulence, cavitation, and survivability of fish present in a flow of water passing through the turbine, the turbine including a turbine runner of the type comprising a hollow hub having a longitudinal axis and an outer surface and M blades pivotally connected to the hub, each blade having an outer surface and a distal inner surface disposed proximate the hub, a leading edge and a trailing edge separated by a water directing surface having an inner portion extending from the inner surface and an outer portion extending from the outer surface, the inner portion being of a given chordal distance in a root region proximate the inner surface, each blade being movable about a trunnion axis from a maximum pitch position, in which the inner portion of the water directing surface extends substantially in a direction of the water flow, to a minimum pitch position in which the outer portion of the water directing surface is substantially perpendicular to the water flow, each blade inner surface forming a gap with the hub outer surface, at least a portion of the gap increasing in size as the blade rotates from the maximum pitch to the minimum pitch, the method comprising the steps:

• removing the turbine runner from a passageway;
• positioning an improved turbine runner in the passageway so that water impinges upon water directing surfaces of the improved runner as the water passes through the passageway, the improved turbine runner comprising:
• an improved hollow hub having an outer surface and a longitudinal axis;
• and
• N improved blades pivotally connected to the improved hub about respective trunnion axes, each improved blade having an inner portion of a reduced chordal distance in a root region proximate the inner surface, N being an integer at least equal to M times de ratio of the given chordal distance to the reduced chordal distance.