Hydraulic turbine

A hydraulic turbine comprising a turbine runner having at least two runner blades each having a corkscrew configuration, wherein each of the at least two runner blades has a leading edge and a trailing edge, and edge zones at the leading and trailing edges;

• and wherein the rate of pressure change along each runner blade is less than 80 psi/second between edge zones at its best efficiency point.

A hydraulic turbine comprising a turbine runner having at least two runner blades each having a corkscrew configuration, wherein the turbine runner is adapted for use in water having a tailwater elevation and wherein the turbine runner has a main fluid flow path defined at least in part by the at least two turbine runner blades having trailing edges at the tailwater elevation;

• and wherein the turbine runner is at least 80% efficient and the minimum absolute pressure maintained along the main fluid flow path within the runner is greater than 4 psia at its best efficiency point.

A turbine runner having at least two runner blades each having a corkscrew configuration, wherein each of the at least two runner blades has a leading edge and a trailing edge, and edge zones at the leading and trailing edges;

• and wherein the rate of pressure change along each runner blade is less than 80 psi/second between edge zones at the trailing edges and at the leading edges of each blade.

A turbine runner having at least two runner blades each having a corkscrew configuration, the turbine runner being adapted for use in water having a tailwater elevation, wherein the turbine runner has a main fluid flow path defined by the at least two turbine runner blades, and wherein each of the at least two turbine runner blades has a trailing edge located at the tailwater elevation, and wherein the turbine runner is at least 80% efficient and the minimum absolute pressure maintained along the main fluid flow path within the runner is greater than 4 psia at its best efficiency point.

A turbine runner having at least two runner blades each having a corkscrew configuration, wherein the turbine runner is at least 80% efficient at its best efficiency point and achieves a rate of pressure change less than 80 psi/second at substantially all points along the main flow.

A turbine runner comprising a hub, the turbine runner having a runner diameter, and at least two runner blades along the hub, each of the at least two blades having a leading edge with a leading edge length;

• and wherein the ration of the sum of the leading edge lengths to the runner diameter is less than 1.0, wherein the turbine runner is at least 80% efficient at its best efficiency point, and achieves a rate of pressure change less than 80 psi/second at substantially all points in the main flow.

A turbine runner comprising a hub, the turbine runner having a runner diameter, and at least two runner blades along the hub, each of the at least two blades having a leading edge with a leading edge length;

• and wherein the ration of the sum of the leading edge lengths to the runner diameter is less than 1.0, wherein the turbine runner is adapted for use in water having a tailwater elevation, wherein the turbine runner has a main fluid flow path defined by the at least two turbine runner blades having trailing edges at the tailwater elevation, and wherein the turbine runner is at least 80% efficient and the minimum absolute pressure maintained along the main fluid flow path within the runner is greater than 4 psia at its best efficiency point.

A turbine runner comprising at least two runner blades, the turbine runner having a runner diameter, an axial length, and a hub, the at least two runner blades being located along said hub, wherein the aspect ratio of the axial length to the runner diameter is greater than approximately 0.6, and wherein the turbine runner is at least 80% efficient at its best efficiency point and achieves a rate of pressure change less than 80 psi/second at substantially all points along the main flow.

A turbine runner comprising at least two runner blades, the turbine runner having a runner diameter, an axial length, and a hub, the at least two runner blades being located along said hub, wherein the aspect ratio of the axial length to the runner diameter is greater than approximately 0.6, and wherein the turbine runner is adapted for use in water having an associated tailwater elevation, wherein the turbine runner has a main fluid flow path defined by the at least two turbine runner blades each having trailing edges located at the tailwater elevation, and wherein the turbine runner is at least 80% efficient and the minimum absolute pressure maintained along the main fluid flow path within the runner is greater than 4 psia at its best efficiency point.

A turbine runner comprising:

• a hub;
• and means for producing a turbine runner efficiency of at least 80% at its best efficiency point and a rate of pressure change less than 80 psi/second at substantially all points along said means, said means being located along said hub.