WO2020110133A1

WO2020110133A1 - Vertical axis gliding blade wind turbine

Info

Publication number: WO2020110133A1
Application number: PCT/IN2019/000010
Authority: WO
Inventors: Ethirajulu Damodaran
Original assignee: Ethirajulu Damodaran
Priority date: 2018-11-26
Filing date: 2019-04-05
Publication date: 2020-06-04
Also published as: EP3908745C0; ES2957404T3; EP3908745A4; EP3908745A1; US20210348593A1; EP3908745B1

Abstract

A vertical shaft with a wind turbine on its top with a generator or alternator at its bottom generates electricity driven by wind force. The turbine blades which are flat long and broad, unlike the existing fixed blades, are unique as they change their orientation from knife to blade mode and then blade to knife mode while rotating, eliminating wind drag and ensuring free flow of wind and smooth rotation of the turbine, leading to increased conversion of the wind energy into electrical energy. This novel design can be used for replacing all the existing and operating windmills all over the world, by upgrading to this gliding blade turbine design, leading to multiple fold increase in the operating efficiency and power generation at minimal cost. With this design, new rooftop, commercial and industrial grade wind mills can be fabricated offering eco-friendly, efficient and cost effective power generating systems.

Description

VERTICALAXIS GLIDING BLADE WIND TURBINE

Description

Background:

For the last so many years, windmills operating all over the world are designed using fixed blade turbines. Further, to increase the torque, long narrow blades with bulge at the bottom have been used. Wind drag and consequent reduction in conversion efficiency have been the in-built disadvantages of these designs.

Mr. Alfred Betz, the pioneer in fluid dynamics has declared that at any given time, a maximum of 59% of the wind energy can be converted into kinetic energy on the basis of fluid dynamics. But, till date, because of the above stated drag factor, all the current wind mills are able to harvest only 30 to 35% of the wind energy and convert it into electrical energy.

To get over these drawbacks, attempts were made in horizontal axis designs, to increase efficiency by designing various modifications to the blades or providing unimaginably long blades or with a folded leaf like blade with a slight curve at their tip. Only very marginal improvements could be achieved due to these changes. Thus the largest windmill weighing around 3500 tones could produce only 8 megawatts of power so far.

In the vertical axis designs, attempts were made to alter the orientations of the blade and frame structures but could not achieve any major improvement. Thus, till date, the horizontal axis windmills are the widely prevalent: power producing windmills throughout the world.

To ensure free uninterrupted flow of wind, the windmills are also being located in the mid-seas_, but with very limited further improvements in power generation.

Summary of the present invention:

To overcome the above stated deficiencies in the current designs of windmills, it is now being proposed to make use of a vertical axis wind turbine. The turbine blades are designed to change their orientation from knife to blade and then blade to knife while rotating, eliminating wind drag and ensuring free flow of wind and smooth rotation leading to increased conversion of the wind energy into electrical energy. Unlike the existing fixed blades, they are unique in design being flat, broad and long.

This novel design can be used for replacing all the existing and operating windmills all over the world by upgrading to this gliding design leading to multiple fold increase in the operating efficiency and power generation at minimal cost. This design would be ideally suited for roof top wind. mi 11s due its height.

Thus, as incorporated in this invention, the turbine blade travels along with the wind being pushed by it, with the blade side facing the wind along its semicircular trajectory till it reaches the half way mark of a circle. In other words, for one half of the circle ( 180 degrees) it travels as a blade and on reaching half way mark of the circle, aided by the tilting lever, it tilts and changes its shape into knife and covers the remaining half of the circle{180 degrees) as such by gliding upon the glide ring.

In Figure 1 , the above embodiment is shown pictorially as an erected windmill tower. The mill tower(l ) vertical shaft(2), shaft housing(3), blades(4), central hub(5), blade shaft(6), tilting lever (7), glide ring (8), blade direction stabilizer (9), base plate(lO) wind wanefl 1) and alternator(12).

Figure 2 shows the part of the windmill as face down view, showing the blades(4) , the central hub(5) glide ring(8)and two of the blades in blade orientation and the remaining two in knife orientation.

Figure 3 shows the blade(4) semi circular glide ring(® ),base plate(lO), tilting lever(7) central hub(5) and wind wane(l 1).

Figure 4 shows the.central hub (5) blade (4) and blade shaft (6).

Figure 2 and 3 also show the functioning of the tilting blades(4) and central hub (5) ,as side view, starting from point X which is at 0 degree on the horizontal line to point Y which is at 180 degrees , the blade travels pushed by the wind. On reaching point Y , it gets tilted and varies its orientation into a knife form and continues its travel as such for the remaining 180 degrees of its circular orbit, piercing through the wind eliminating wind drag and resistance.

Operating Mechanism of this Design:

As given in Figures 2 and 3, when wind hits the blade A at point X facing it, the turbine starts to move, whereby subsequent blade D which is near point X shifts its orientation from the knife mode to blade mode, aided by the glide ring’s abrupt 90 degree steep fall and the blades rear end which is heavier than the front end, - enabling it to glide down and tilt as a blade .

During this process when blade B in blade mode which is close to point Y, gets pushed upwards by the glide ring’s tilting lever, making it to change its orientation from blade to knife and travel as such along the semicircle riding upon the glide ring, till it reaches point X, crossing point Y-2..

When this happens, blade C which is in knife orientation near point Y-2 travels onwards as such till it reaches point X and shifts its orientation from knife to blade mode aided by the glide ring’s abrupt end and steep fall.

The simultaneous change in orientation of the four blades, from blade mode to knife mode and knife mode to blade mode, with the aid of the wind thrust is achieved by the unique design of the tilting lever and gliding blades.

The shaft of the blades are uniquely designed whereby the blade is securely fastened to the blade shaft (6) by its reduced handle cum neck and sealed with a cup and locked with provision of a hole in the middle for facilitating easy rotation of the blade alone. This narrow neck prevents the blade from sliding out of the shaft in its circular orbit. The shaft is firmly secured to the hub by means of techniques well known to the art. Wind being known for its varying speed and direction, would make the blades to wobble in their circular orbits in both the orientations. Safeguards should therefore be made at all times to arrest this. To achieve this, the semicircular glide ring’s elevation arrests the blades in knife mode from reversing their orientation and like wise the blade direction regulator arrests the blades from sliding back into knife mode.

To eliminate friction, noise and loss of torque, the glide ring, tilting lever and blade handles are lined with suitable friction eliminating materials.

At times of emergency, when the turbine needs to be halted, a design provision is made to withdraw the tilting lever whereby the blades’ orientation as blade is prolonged, leading to halting of the turbine due to the wind flow on all the four blades arresting the turbine’s rotation.

Claims

CLAIMS:

A wind generator(Fig.l) consisting of a vertical axis shaft (2) incorporating gliding-varying blade (4) comprising of

a) a vertical shaft (2) securely fastened with a turbine hub(5) attached with four gliding - varying blades (4),

b) Where the position of the blade shaft (6) is fixed, while the attached blades (4) alone revolve around it changing its orientation from the knife mode to blade mode and vice versa.

c) Where the blade (4) is securely fastened to the blade shaft (6) by its reduced handle cum neck and sealed with a cup and locked with provision of a hole in the middle for facilitating easy rotation of the blade alone.

d) Where the blade’s (4) varying orientation is achieved by the tilting levermounted on the base plate (10), which starts rising from its initial point, till it reaches the blade shaft (6) level gradually and then ends abruptly after covering halfway mark of its circular orbit with a steep fall.

e) Where the blade (4) guided by the glide rings tilting lever (7) enables the tilting of the blade’s orientation from blade to knife.

f) Where the blade (4) aided by the glide ring’s (8) steep and sudden fall changes its orientation from knife to blade.—

g) Where the blade (4) direction stabilizer (9) ensures the smooth rotation of the turbine without being disturbed by the changing wind, course and direction preventing the resultant wobbling.

h) Where the semicircular glide ring (8) likewise prevents the wobbling of the blade (4) while it is in its knife mode of orbit

2. The windmill turbine of claim 1 wherein the shape of the blade (4) is designed in a

rectangular, flat and broad manner for harvesting maximum wind thrust leading to increased power generation.

3. The wind mill turbine of claim 1, wherein the design of the gliding- varying blade (4) turbine mounted on top of the shaft (6) by its sideways circular movement facilitates mounting broad and long blades leading to increased torque and power generation. The windmill turbine of claim 1, wherein with four blades (4), one each at 90 degree angle of variation, enables mounting of broad and long blades

(4) Resulting in uninterrupted harvesting of the wind thrust leading to increased harvesting of torque and maximization of power generation.