Turbine assembly

An apparatus for generating electricity from water flow comprising:

• a mixing tube having a first end and a second end opposite the first end;
• a convergent section connected to the first end of the mixing tube such that a venturi is defined between the end of the convergent section and the mixing tube;
• a diffuser section connected to the second end of the mixing tube, the diffuser section configured such that, in use, the pressure at an exit of the diffuser section is greater than the pressure at the venturi;
• a turbine tube comprising a blade assembly having a plurality of blades, the turbine tube supported in the convergent section such that an annulus is defined between the turbine tube and the convergent section to form a first flow passage for a primary flow, and the turbine tube defining a second flow passage for a secondary flow through an interior of the turbine tube, wherein the turbine tube is rotatably mounted in the convergent section and the blades are attached to an inner surface of the turbine tube such that in use water flow past the blades drives the rotation of the turbine tube, and wherein the mixing tube is configured such that in use the primary flow mixes with the secondary flow in the mixing tube to form a mixed flow that enters the diffuser section, wherein the turbine tube is rotatably mounted in a support boss, the support boss mounted in the convergent section by support vanes;
• and
• a blower fan located radially about the turbine tube, to draw air into a space between the turbine tube and support boss via a conduit that extends through one of the support vanes.