WO2013171320A1 - Wind motor with rotational axis substantially perpendicular to the wind direction - Google Patents

Description

 Wind power machine with axis of rotation substantially perpendicular to the wind direction

The invention relates to a windmower ine with axis of rotation substantially at right angles to the wind direction.

Known wind turbines are i.d.R. distinguished according to the position of the axis of rotation of the wind rotor. So you can distinguish between rotors with vertical and horizontal axis of rotation.

For the use of wind power generation almost exclusively wind converter with horizontal position of the axis of rotation in propeller type are realized, which is due to their relatively high energy yield per over-swept area. However, these wind turbines also have their disadvantages such as: strong dynamic loads of the tower by arranging the generator and the gearbox at high altitude, volume, shadows, bird strike, icing, poor accessibility of the generator. Thus, the drawbacks such as shadow cast and volume prevent e.g. so far also a large-scale application of these wind generators in cities or on skyscrapers.

Although wind rotors with a vertical axis of rotation are the oldest type of construction, they have not yet been able to prevail in power generation. The best known representatives are the Savonius rotor, the Darrieus rotor and a modification of the Darrieus rotor, the H rotor.

The Savonius rotor is independent of the wind direction due to the symmetrical structure and starts even at low wind speeds with high torque. Due to the low speed and the comparatively low power coefficient, it is out of the question for electricity generating wind turbines. It is occasionally used for the mechanical drive of water pumps or as a start-up aid for other wind rotors. The Darrieus and H-rotors are wind independent and basically have a simple design. In addition, it is possible to attach the mechanical and electrical components, gear and generator, but also control system on the ground. However, they have a worse performance coefficient, so that even at lower construction costs the economy is called into question.

The invention has for its object to provide a wind turbine, which combines advantages of a wind turbine with horizontal axis of rotation in propeller type in terms of power output with the structural advantages of a vertical axis of rotation by arranging the generator at the bottom of the wind turbine and by their nature, such disadvantages of wind turbines with horizontal axis of rotation as shadow and volume, bird strike, ice break has largely not, so they eg can also be used on rooftops application.

This object is achieved by a wind power machine according to claim 1. In a wind power machine according to the invention with a rotation axis i.W. At right angles to the wind direction, wind becomes in an inflow channel whose input cross-section is opposite to the wind direction, i. to the windward side, is aligned, caught.

Further embodiments are the subject matter of the subclaims or described below.

The substantially perpendicular position of the axis of rotation to the wind direction is achieved by a vertical axis of rotation is selected and / or optionally a means for skewing the axis of rotation is selected, so that an alignment of the axis of rotation is made possible on the wind direction.

Preferably, the inflow channel is round, oval, square, triangular or n-square executed.

In the case of the wind power engine according to the invention, a wind-catching region which is optimally shaped in terms of flow is preferably located outside the inflow passage arranged curved walls. The bending radius of the walls of the windscreen area should be 0.15 - 0.3 times the respective side length of the inflow channel. The windscreen area serves to minimize the considerable flow losses when the wind enters the inlet channel.

Preferably, the overhead wall of the inflow channel extends over the underlying, thus forming a kind of roof.

Preferably, the inlet channel after wind enters an arc of 90 ° to the axis of rotation.

In addition, the inflow channel may be formed as a tapered nozzle. For this purpose, the output cross-section of the inflow channel in the course of the flow direction upon reaching the 90 ° angle is preferably lower than the input cross-section. The conical design forms a compact air flow with high speed and high volume flow, which increases the performance of the wind turbine.

The optimal throat angle for a circular nozzle is 12-14 °, giving the flow coefficient a maximum value of 0.94-0.95, while the speed coefficient is around 0.96. The nozzle shape of the inflow channel should thus also have a narrowing angle of 12-14 °.

The bottom wall of the inflow is executed bent. Here, the bottom wall does not participate in the cone formation (= nozzle formation), since the expected flow separation of the nozzle effect is small, so that the constriction angle for the nozzle shape of the inflow is only 6-7 °. The overhead wall of the inflow is also bent.

With a predominantly round cross-section of the inflow channel, the top and bottom walls merge into one another. With a predominantly angular cross-section, the inflow channel is closed by side walls that follow the curved shape of Adjust the bottom and top wall.

The sharper the inner wall is bent, the greater the likelihood of flow separation from the lower inner wall portion of the inflow channel. This has serious consequences because the rotor blades are not optimally loaded and thus the performance of the wind turbine decreases. This effect increases with increasing wind speeds. Therefore, one or more vanes with or without profiling may be mounted inside the inflow channel. Preferably, the vanes are connected to the side portions of the inflow channel. It is preferable to design the guide vanes rotatable and controllable, so that in strong winds the influx of wind energy to the rotor blades can be throttled or completely prevented. Of course, this function can also ensure flaps at the inlet or outlet of the inflow.

After passing through the vane (s), the wind flow hits the hub with the rotor blades. Previously, in inflow channels with square cross-section still a transition part should be inserted, which ensures the transition from a square to a round cross-section. The region of the inflow channel in which the rotor lies with the rotor blades usually has a round cross section.

The wind stream is preferably converted into rotational energy by two or more profiled rotor blades fastened to a hub.

The rotational energy is transmitted from the hub via an axle with or without clutch or axleless, e.g. transmitted via a magnetic coupling, either via an intermediate gear or directly to a generator in which the rotational energy is converted into electrical energy. The derivation of the electrical energy is then i.d.R. via a suitable cable.

The generator is usually firmly connected to the mast.

To increase the power of the wind turbine is located at the output of Inlet after the rotor blades an ejector surface, which may be both flat and curved. This surface is located on the same side as the windscreen area, based on the curved surface of the inflow, so against the Windanströmung on the windward side of the wind turbine. As a result of

Flow around this ejector surface by the wind creates a negative pressure on the leeward side below the rotor blades. By this negative pressure below the rotor blades of the wind flow is accelerated or sucked out of the inflow, which contributes significantly to the increase in power of the wind turbine.

Suitable shapes of this plane or curved Ejektorfläche are round, oval, square, triangular or even n-shaped. Preferably, this ejector surface is pulled over half the diameter on the windward side.

To reduce the flow losses when hitting the hub, an aerodynamically optimally shaped hood can sit above the hub. The constriction angle of the hood against the direction of flow of the wind is ideally 12- 14%. This geometry also provides for the formation of a nozzle shape in the flow channel, so that the wind flow is further accelerated.

Due to the energy contained in the wind and the possibly existing profiling of the rotor blades they are rotated. In order to optimize this according to the wind speed, a blade pitch mechanism can be provided which optimally positions the rotor blades against the wind flow. To save costs, the rotor blades can also be rigidly attached to the hub.

Preferably, a diffuser is initially arranged between the inflow channel and the plane or curved ejector surface, possibly also at a transition piece, the expansion angle for the diffuser preferably being in a range between 6 ° and 12 °. At the same time as the ejector surface enlarges, the suction effect thereof can be increased. As a result, the throughput of wind flow through the wind turbine increases and more electric power can be generated. Preferably, the body, which is formed from the windscreen area, the inflow, possibly the transition piece, possibly the possibly downstream diffuser and possibly the Ejektorfläche rotatably mounted in a holder. Here, for reasons of better statics, the mentioned components can certainly be stored at two points and the upper part, for example, with appropriate wires, be braced.

Alternatively, the hub with the rotor blades via a bearing, a sliding or ball bearings, fixed and rigidly connected to the bracket or with the body. The connection to the generator takes place in this case by a flexible, ie flexible shaft. With this configuration, the slip between the rotor blades and the body can be minimized because possible relative movements of the body due to high wind loads do not cause the rotor blades to drag on the latter.

Preferably, the input cross section and optionally the plane or curved ejector surface are aligned counter to the wind direction (to the windward side) by a wind direction tracking. This can be done both electrically via a corresponding control with servomotor, as well as mechanically.

Preferably, to minimize the force required for the wind direction tracking by moving back the inlet cross section of the inflow to the axis of the mast of the inflow even to Windrichtungsnachführung, preferably the inflow is extended by moving the input cross section through S-shaped walls, so that the wind flow from the inflow channel fluidically optimally meets the rotor blades.

Preferably, the entire body is equipped with a sound-absorbing coating or made of sound-absorbing material to minimize the noise emissions. Preferably, in strong wind to protect against destruction, the wind kraftnnasch either braked by an electronic brake (eg by a short-circuit brake), rotated by the Windrichtungsnachführung from the wind or closed the input or output section of the inflow through adjustable flaps or the like. This function can also be taken over by the guide vanes or the incident wind power can be controlled via this, so that the system can be operated even in strong winds.

The invention will be explained in more detail with reference to the following figures. Show it:

Figure 1: a wind turbine according to the invention in side view and cross section;

Figure 2: the windscreen area to a quadrangular shape of the cross section of the inflow to the wind turbine according to the invention according to Figure 1;

FIG. 3 shows a further embodiment of the wind power machine according to the invention in a side view with a covered entrance area;

FIG. 4 shows a plan view from above of a wind power machine according to the invention with an ejector surface;

FIGS. 5a to 5c show a vertical cross section of the inflow channel of wind power machines according to the invention with different embodiments of the guide vanes;

FIG. 6 shows a further embodiment of a wind power machine according to the invention with a diffuser;

FIG. 7 shows a further embodiment of a wind power machine according to the invention with special shaping of the inflow channel as wind direction tracking;

FIG. 8: Partial view of an alternative embodiment of the lower area Wind turbine according to the invention with rigid mounting of the hub bearing;

FIG. 9a shows an embodiment of a wind power machine according to the invention with a rectangular windscreen area and three guide vanes in a perspective view obliquely from the front;

FIG. 9b shows a view of the wind power machine according to the invention from FIG. 9a obliquely from behind;

Figure 9c: Perspective view of the transition piece and rotor of the wind power machine according to the invention according to Figure 9a;

Figure 10: embodiment of a wind turbine according to the invention in side view and cross section;

11a: embodiment of a wind power machine according to the invention with windscreen area with opening in the form of an isosceles trapezium and three guide vanes in front view;

FIG. 11b: a view of the wind power machine according to the invention according to FIG. 11a from obliquely in front;

FIG. 11c: a view of the wind power machine according to the invention according to FIG. 11a from above;

FIG. 11d: view of the wind power machine according to the invention according to FIG. 11a from obliquely below;

FIG. 12a shows an embodiment of a wind power machine according to the invention with a covered entrance area and three guide vanes, viewed obliquely from the front;

FIG. 12b: view of the windmill according to the invention in accordance with FIG. 12a of FIG diagonally behind;

Figure 12c: View of the lower portion of the windmill invention according to the invention in Figure 12a without Ejektorfläche and diffuser obliquely from below;

FIG. 12d shows a wind turbine according to the invention according to FIG. 12a in side view and cross section;

13a shows an embodiment of a wind power machine according to the invention with the inlet channel as additional wind direction tracking, formed by moving back the rectangular inlet cross-section to the mast axis, with two guide vanes at the outlet of the inflow channel, oblique view from the front;

FIG. 13b shows a perspective view of the inflow channel of the wind power machine according to the invention from FIG. 13a obliquely from below;

13c shows a wind turbine according to the invention according to FIG. 13a in a side view in cross section;

Figure 14a: embodiment of a wind turbine according to the invention with the inlet channel as additional wind direction tracking, formed by moving back the input section to the mast axis, and a windscreen area with opening in the form of an isosceles trapezium, oblique view from the front;

Figure 14b: view of the invention windmill ine of Figure 14a obliquely from behind;

Figure 15a: view of an embodiment of a transition piece obliquely from above;

Figure 15b: perspective view of the embodiment of the inverted transition piece of Figure 15a; FIG. 16: constriction angle for a circular nozzle;

FIGS. 17a and 17b: constriction angle of the inflow channel;

FIG. 18: expansion angle of the diffuser;

Figure 19: Bending radius of the walls of the windscreen area.

Figure 1 shows a windmill according to the invention ine 1 in the side view. Through a windscreen area 3, the wind flows through the inlet channel 2, which has an upper wall 5 and a lower wall 4, which merge into one another. In the inflow passage 2, a guide vane 6 is arranged. At the inlet channel 2, a transition piece 9 connects, which allows the transition from a polygonal cross-section to a circular cross-section. In the transition piece 9 is the rotor, consisting of arranged on a hub 7 rotor blades 8. The rotor is connected to the generator 1 1, which sits on the mast 12. On the hub 7, a hood 10 is set. At the transition piece 9, an ejector surface 13 connects, which extends the inflow 2 on the side of the underlying wall 4. By the Windrichtungsnachführung 18 of the wind turbine, which is shown here by way of example in the form of a wind vane with triangular shape, the inflow 2 is frontally aligned with the wind direction (in windward direction). In order to make this possible, the parts necessary for the flow guidance of the wind in the wind power machine are rotatably mounted in a holder 15. The windscreen area 3 has outwardly curved walls. The bending radius of the walls of the windscreen area 3 should be 0.15 to 0.3 times the respective side length of the inflow channel 2.

FIG. 2 shows the windscreen area 3 for a quadrangular shape of the cross section of the inflow channel 2.

As FIG. 3 shows, the upper wall 5 of the inflow channel 2 may extend beyond the lower wall 4, so that a roofed entry wall 5 may extend. range in the inflow 2 results.

FIG. 4 shows schematically the view from above of a wind power engine according to the invention. Again, the nozzle-like design of the inflow 2 is clearly shown. The course of the ejector surface 13 is indicated by a dashed line. The ejector surface 13 can be arranged over half the diameter of the cross section of the inflow channel.

FIGS. 5a to 5c show some embodiments of the guide vanes which are connected to the side regions of the inflow channel 2.

Figure 6 shows an embodiment of the wind power machine 1 according to the invention, in which after the inflow 2 still a diffuser 14 at the square

Inflow channel existing transition piece 9 is attached.

The body, which results from the windscreen region 3, the inflow channel 2, the transition piece 9, the downstream diffuser 14 and the ejector surface 13, is rotatably mounted on the mast 12 by means of a holder 15 and a sliding or ball bearing. Figures 1 and 3 show a corresponding storage. A wind direction tracking 18 with control / cross flag is provided in the embodiments shown there.

FIG. 7 shows an embodiment of a wind power engine 1 according to the invention, in which the input region of the inflow channel 2 is moved back to approximately the axis of the mast 12. In that case, the inflow channel 2 itself serves as a wind direction tracking. The inlet channel 2 and the top wall 5 is by an S-shaped curved wall 16 and the underlying wall 4 is by an S-shaped curved wall 17 and the side walls of the inflow 2 are extended by S-shaped curved walls.

FIG. 8 shows an alternative lower subregion of wind power machines according to the invention, in which the hub 7 with the rotor blades 8 rotates via a bearing 19. bar is fixed, which in turn is connected to a rigid attachment 20 with the bracket 15. The connection to the generator 1 1 is made by a flexible (flexible) shaft 21st The illustrated wind power machine has wings which serve as an attack surface for the wind, as wind direction tracking 18.

FIGS. 9a to 9c, 10, 11a to 11d, 12a to 12d, 13a to 13c and 14a and 14b show different embodiments of the wind power machine according to the invention.

The two embodiments of a wind power engine 1 according to the invention shown in FIGS. 9a to 9c and 10 have a rectangular windscreen area 3. In the inflow 2, three vanes 6 are arranged in each case, which pass through the inflow 2. Figure 9c clearly shows the transition piece 9, which provides the transition of the inlet channel 2 with a rectangular cross-section in the region of round cross section, in which the rotor is located with the rotor blades 8 connected to the hub 7. The embodiment shown in Figures 9a to 9c and the embodiment of Figure 10 also have a

Ejektorfläche 13 on. As Windrichtungsnachführung 18 each wing are provided.

The embodiment of a wind power machine 1 according to the invention shown in FIGS. 11a to 11d has a windscreen area 3 with an opening in the form of an isosceles trapezium. This geometry is continued by the inflow channel 2. The embodiment shown also has three guide vanes 6 arranged in the inflow channel 2 and an ejector surface 13.

Figures 12a to 12d show an embodiment of a wind power machine 1 according to the invention, in which the windscreen area 3 is a covered inlet area. The cross section of the windscreen area 3 is rectangular. in the

Inflow 2, three vanes 6 are arranged. The embodiment also has an ejector surface 13. In the embodiment of a wind power machine 1 according to the invention arranged in a rotatably mounted holder 15, which is shown in FIGS. 13a to 13c, the windscreen area 3 likewise has a rectangular cross section. In the lower region of the inflow channel 2, two guide vanes 6 are arranged. Also, an ejector surface 13 is present. The input cross-section of the inflow channel 2 is moved back to approximately the axis of the mast 12, that is arranged approximately in position of the axis of rotation of the rotor, so that the inflow channel 2 itself serves as Windrichtungsnachführung.

FIGS. 14a and 14b show a further embodiment of a wind power machine 1 according to the invention. This likewise has a recessed input cross-section of the inflow channel 2. The windscreen area 3 has a cross-section - an opening - in the form of an isosceles trapezium.

Figures 15a and 15b show a transition piece 9 in two different views, which allows the passage of a channel, such as the inflow channel 2, from a square to a round cross-section.

For a better understanding of the present invention, important angles are shown diagrammatically in FIGS. 16 to 19.

FIG. 16 shows the constriction angle β for a circular nozzle.

FIG. 17a shows how the constriction angle β of the inflow channel 2 is to be carried out, wherein the windscreen area 3 need not be considered further. The wind power machine is shown in the figure in the top view. The ejector surface 13 located below the inflow channel 2 is indicated by a dashed line. In the case of a symmetrically shaped inflow channel 2 as in the present case, the constriction angle on both sides of the inflow channel 2 is the same and amounts to β / 2. Figure 17a relates to the constriction angle, which indicates the degree of narrowing of the inflow channel 2 in the width.

FIG. 17b, on the other hand, shows how the constriction angle .beta. / 2 of the inflow channel 2 leads to the Marking the degree of constriction between the bottom wall 4 and the top wall 5 of the inflow 2 is determined. For this purpose, the diameter A of the input cross section and the diameter B of the output cross section of the inflow channel 2 are drawn as a vertical side by side on an imaginary line. From the line to the lower of the two diameters, here B, a line parallel to the imaginary line, ie a perpendicular to the two verticals symbolizing the diameters A, B, is drawn. Another dashed line C, which corresponds to the length of the top wall 5, establishes the connection between the two upper ends of the verticals standing for the diameters A and B. The included angle between this line C and the drawn perpendicular to the lines which represent the diameters A and B is the sought narrowing angle β / 2.

As FIG. 18 shows, the determination of the expansion angle α or a / 2 of the diffuser 14 is similar to the determination of the narrowing angle of the inflow channel.

FIG. 19 shows what is meant by the bending radius of the windscreen area 3. In the illustrated embodiment of a combination of inlet channel 2 and windscreen area 3, the outer wall of the transitional area between inlet channel 2 and the outermost point of the windscreen area 3 describes a circular arc from which the bending radius r can be determined.

LIST OF REFERENCE NUMBERS

Windmower ine

inflow

Porch area

bottom wall of the inflow channel top wall of the inflow channel vane / n

hub

rotor blades

Transition piece

spinner

generator

mast

Ejektorfläche

diffuser

Swivel mounted bracket

S-shaped curved wall

S-shaped curved wall

Yaw

camp

attachment

Flexible shaft

Claims

claims 1. windmower ine (1) with axis of rotation substantially perpendicular to the wind direction, characterized in that the wind power machine (1) has a Inflow channel (2) with windscreen area (3). 2. Wind power machine (1) according to claim 1, characterized in that the inflow channel (2) extends in an arc of about 90 ° to the axis of rotation. 3. Wind power machine (1) according to claim 2, characterized in that the output cross section of the inflow channel (2) in the course of the flow direction upon reaching the 90 ° angle is less than the input cross-section. 4. Wind power engine (1) according to one of the preceding claims, characterized in that in the inflow passage (2) one or more vanes (6) are arranged with and / or without profiling. 5. Wind power machine (1) according to claim 4, characterized in that the guide vane / guide vanes (6) is rotatable and / or controllable executed / are. 6. Wind power machine (1) according to one of the preceding claims, characterized in that the inflow channel (2) has a round, quadrangular, triangular or n-angular cross-section. 7. Wind power machine (1) according to claim 6, characterized in that the inflow channel (2) is transferred in an angular cross section in the vertically extending region by a transition piece (9) in a round cross section. 8. Wind power machine (1) according to one of the preceding claims, characterized in that the wind energy by two or more on a hub (7) fixed profiled and / or non-profiled rotor blades (8) is converted into rotational energy. 9. Wind power maschine (1) according to claim 8, characterized in that the rotor blades (8) either via blade bearings with Blattverstellmechanismus or rigidly with the hub (7) are connected. 10. Wind power machine (1) according to one of the preceding claims, characterized in that the inflow channel (2) or the inflow channel (2) with transition piece (9) in the lower region, a diffuser (14) is connected. 11. Wind power machine (1) according to one of the preceding claims, characterized in that the hub (7) with the rotor blades (8) via a bearing (19) is rotatably mounted, wherein the bearing (19) by a rigid attachment (20) with a holder (15) or the inflow channel (2) or optionally a transition piece (9) or possibly the diffuser (14) is connected and the connection with a generator (1 1) by a flexible shaft (21). 12. Wind power machine (1) according to one of the preceding claims, characterized in that in the lower region of the inflow channel (2) or below the transition piece (9) or the diffuser (14) to the windward side an ejector surface (13) is arranged. 13. Wind power machine (1) according to one of the preceding claims, characterized in that the wind power machine has a wind direction tracking (18). 14. Wind turbine (1) according to one of the preceding claims 2 to 13, characterized in that by arranging the inlet cross-section of the inflow channel (2) approximately in position of the axis of rotation of the inflow channel (2) itself serves for Windrichtungsnachführung.