Gravitational vortex water turbine assembly

A gravitational vortex water turbine assembly, comprising:

• a spiral-shaped vortex basin configured to induce a vortex having a substantially vertical central axis in a water flow under the influence of gravity, the spiral-shaped vortex basin comprising a side wall with a tangential inflow opening for supplying the water flow to the vortex and a bottom with a central outflow opening for discharging the water flow of the vortex,
• a water turbine, disposed under the spiral-shaped vortex basin, coaxially with the substantially vertical central axis of the vortex, comprising a turbine housing, coupled to the central outflow opening, and a turbine rotor,
• wherein the turbine rotor comprises a central rotor hub and rotor blades attached thereon, and
• wherein the rotor blades:
• comprise an upstream end at an upper side of the rotor blades and a downstream end at a lower side of the rotor blades, a smallest angle between the substantially vertical central axis and a plane tangent to the upstream end is smaller than a smallest angle between the substantially vertical central axis and a plane tangent to the downstream end;
• at a radially inward end have a larger angle between a vertical plane tangent to the radially inward end and a plane through the substantially vertical central axis and through the radially inward end than an angle at a radially outward end between a vertical plane tangent to the radially outward end and a plane through the substantially vertical central axis and the radially outward end;
• and
• at the radially inward end have a smaller angle between the radially inward end and a plane perpendicular to the substantially vertical central axis than an angle at the radially outward end between the radially outward end and a plane perpendicular to the substantially vertical central axis and through the radially outward end,
• such that the rotor blades are configured to absorb the tangential, axial and radial component of the water flow of the vortex.