Subj ect Matter of the Invention

The invention discloses a helical hydrokinetic turbine that generates electrical energy from the kinetic energy of flowing water .

Known State of the Art

Today, hydroelectric power plants (HPPs ) and dams are widely used in electric power generation . However, hydroelectric power plants have high installation and operation costs and cause agricultural areas to be flooded . Moreover, these power plants are constructed only in regions with suitable topography . In this case , the energy available in rivers where it is not possible to construct hydroelectric power plants cannot be utili zed .

In the known art , in order to convert energy in flowing rivers into electricity, it is necessary to develop environmentally friendly turbines which are , suitable for any desired section of a river and easy to install .

The patent document US2010140947A is an example of the known state of the art . The document discloses a high ef ficiency turbine and a method of generating power . The present invention relates to a turbine comprising a pair of opposing end discs concentrically aligned with a central axis of the turbine and a plurality of blades extending between the end discs . At least one end disc is adapted for operating with a generator for generating power . The blades rotate in a single direction when exposed to fluid flow and thereby rotate the pair of opposing end discs . The blades are interconnected by at least one threaded ring oriented parallel to the pair of opposing end discs and intersecting the plurality of blades . Here , at least one threaded ring is in a concentric alignment with the central axis . The invention further comprises a method for generating power comprising engaging the turbine with a generator to create a turbine generator unit and placing the turbine generator unit within a fluid flow .

The patent document US2010278653 is another example of the known state of the art . The document discloses a vertical axis turbine and a method of making the same . Said turbine comprises a plurality of blades rotatably disposed around an axis of rotation . Each blade is twisted at a first angle about its longitudinal axis . Moreover, distal ends of the blades are located at a predetermined distance from the axis of rotation . Each blade is bent at one or more central locations along the longitudinal axis . Thus , the one or more central locations has/have the same predetermined distance from the axis of rotation as the distal ends . Each blade has a section perpendicular to the axis of rotation for performing unidirectional rotation of the blade about the axis of rotation in a fluid flow . Also , each blade is tilted at a second angle with respect to the longitudinal axis of rotation .

As an alternative to the above documents , a helical hydrokinetic turbine with a speci fic solidity and an appropriate angle of attack has been developed that can be placed hori zontally or vertically in flowing water with a free surface and used in shallow and deep water, that comprises non-symmetrical and shape-optimi zed blade sections for maximum power generation . Detailed Description of the Invention

The invention relates to a hydrokinetic turbine providing a rotational movement by kinetic energy in flowing river water .

The invention is generally a riverine hydrokinetic turbine, comprising at least four helical type turbine blades (1) consisting of optimized blade sections (3) (hydrofoil) providing a rotational movement by fluid flow and having a twist angle; at least two star-shaped support discs (2) and at least one ring-shaped support disc (4) holding the mentioned blades together and supporting them; and a central shaft ( 5 ) .

More specifically, the turbine of the invention comprises

- a central shaft (5) ,

- at least four helical turbine blades (1) positioned around the central shaft (5) , arranged for providing a rotational movement by fluid flow, consisting of blade sections (3) with upper surface being optimized by rounding, and having a twist angle,

- at least two primary support discs attached at their center to the center shaft (5) , positioned against each other and arranged for intersecting their ends with the ends of the blades for holding the blades together and supporting the blades,

- at least one secondary support disc positioned parallel to the primary support disc, arranged for intersecting with the interior of the blades facing the central shaft (5) , being concentric with the central shaft (5) .

In an embodiment of the invention, the optimized blade section (3) is a NACA0018 blade section (3) . Due to the smoothness of the blade section (3) surface, the streamlines diverge at the leading edge and flow smoothly on the upper side. The rounded shape of the upper surface ensures that the water velocity is higher than the lower surface. When the flow velocity on a body increases, two forces, tangential and normal forces occur where they affect the surface. The component of these two forces try to push the blade section (3) against the flow direction at a certain angle (the direction of the resulting force) . The shape of the optimized blade section (3) provides a lift at zero angle of attack in contrast to symmetrical NACA sections.

In an embodiment of the invention, the twist angle is 120 degrees .

In an embodiment of the invention, the primary support disk is attached to the central shaft (5) .

An embodiment of the invention comprises four turbine blades (1) •

In an embodiment of the invention, the primary support disc is a star-shaped support disc (2) .

In an embodiment of the invention, the secondary support disc is a ring-shaped support disc (4) .

An embodiment of the invention comprises two star-shaped support discs (2) .

An embodiment of the invention comprises one ring-shaped support disc ( 4 ) .

In an embodiment of the invention, the central shaft (5) has a diameter of 0.05 m. In an embodiment of the invention, the star-shaped support disc (2) comprises a hole at its center for the central shaft (5) to pass through.

An embodiment of the invention consists of four turbine blades (1) consisting of hydrofoils optimized using NACA0018 blade section (3) (hydrofoil) providing a rotational movement with kinetic energy in the flowing river water; star-shaped support discs (2) in lower-upper part, holding the mentioned blades together and functioning as supports; a ring-shaped support disc (4) in middle part; and a central shaft (5) with a diameter of 0.05 m. Hydrofoils provide the necessary hydrodynamic conditions, allowing the turbine blades (1) to rotate with a maximum efficiency. The turbine blades (1) rotate with water force, allowing the center shaft (5) to rotate. The center shaft (5) transmits the rotational movement to the part that provides electricity generation. The discs serve to attach the turbine blades to the central shaft (5) , and provide a stability for the turbine .

Figure 1 shows a turbine of the invention. Accordingly, the turbine comprises four helical turbine blades (1) consisting of optimized blade sections (3) (hydrofoils) and having a twist angle, two star-shaped support discs (2) and a ringshaped support disk (4) , and a center shaft (5) . Figure 2 shows a comparative view of the blade section (3) of the invention with the blade sections NACA015 and NACA0018. Figures 3 and 4 show the star-shaped support disc (2) and the ring-shaped support disc (4) , respectively.

In an embodiment of the invention, simulations are made using the ANSYS program and the blade sections (3) are obtained as a result of optimization studies. A turbine consisting of four blade sections ( 3 ) twisted at a twist angle of 120 degrees has been developed .

With the invention riverine helical hydrokinetic turbine was obtained that is easy to install , suitable for use in the desired section of a river, environmentally friendly, and does not require an economically high investment cost .

Thanks to the invention, it is ensured that energy in the rivers is converted into electric energy by environmentally friendly methods .

The helical hydrokinetic turbine of the invention can be easily used in shallow and deep waters as it can be placed hori zontally or vertically in flowing water with free surface . Unsymmetrical blade sections ( 3 ) are used in the hydrokinetic turbine and shapes of the blade sections ( 3 ) are optimi zed for maximum power generation . Due to the speci fic solidity and angle of attack considered in the four-blade turbine design, the power obtained is greater than similar turbines . Support arms are attached to the blades within the turbine frame to strengthen the slenderness resistance of the turbine blades ( 1 ) against the drag force of the water . Since the turbine can operate at relatively low flow speeds , the tail water distance is short , providing a free passage for the fish .

Description of the Figures

Figure 1 : A perspective view of the invention .

Figure 2 : A comparative view of an optimi zed blade section of the invention .

Figure 3 : A view of a star-shaped support disc of the invention Figure 4: A view of a ring-shaped support disc of the invention

Description of Reference Numbers in Figures 1. Turbine blades

2. Star-shaped support disc

3. Blade section

4. Ring-shaped support disc

5. Central shaft