DE202012000907U1 - Flow turbine - Google Patents

Abstract

Flow power plant (1; 1 '; 1' '; 1 (3)), in particular a wind turbine, with a plurality of flat blades (6a-6d; 6a'-6d'; 6a ''-6d ''; 6a (3) -6d (3)) which is rotatably mounted about a rotor axis r, which is not parallel to the flow direction s, but preferably approximately perpendicular thereto, wherein the rotor blades (6a-6d; 6a'-6d '; 6a' ' 6a (3) -6d (3)) each have major surfaces which strive away from the rotor axis r and are each rotatable about a blade axis b, and wherein in each case two rotor blades (6a-6d; 6a'-6d ' 6a '' - 6d ''; 6a (3) -6d (3)) are offset from each other by a center angle of about 180 ° about the rotor axis r such that their blade axes b 1, b 2 are in the direction of each 6a-6d, 6a-6d, 6a-6d, 6a-3d), and the rotor blades (6a-6d, 6a'-6d ') associated with each other being 6a '' - 6d ''; 6a (3) -6d (3)) are rotatably coupled together, the art, that the directions of the longitudinal axes q 1, q 2 of their cross sections in each case equal distances to the rotor axis r are rotated by an angle of about 90 ° to each other, characterized in that the ...

Description

The invention is directed to a flow force plant, in particular a wind turbine, with a rotor having several flat blades, which is rotatably mounted about a rotor axis r , which is not parallel to the flow direction s , but preferably approximately perpendicular thereto, wherein the rotor blades each have major surfaces, the strive away from the rotor axis r and are each rotatable about a blade axis b , and wherein two rotor blades are offset by a center angle of about 180 ° about the rotor axis r against each other, such that their blade axes b ₁ , b ₂ toward the each coupled rotor blade, and wherein the rotor blades so mutually associated are rotatably coupled to each other, such that the directions of the longitudinal axes q ₁ , q _{2 of} their cross sections at equal distances to the rotor axis r are rotated by an angle of about 90 ° to each other.

More recently, there has been a marked shift in energy policy premises, particularly in favor of environmentally friendly technologies, which are less harmful to the environment. In addition to solar energy, one of the most preferred energy sources is water and in particular wind power, the latter being available in a huge, practically barely exhaustible potential. In addition, these regenerative energies do not contribute to increasing the CO ₂ balance, as caused by fossil fuels, which is considered to be the main reason for continuing global warming. Furthermore, they are not associated with incalculable risks to humans and the environment, such as those associated with the civilian use of nuclear energy.

Numerous approaches are therefore already known from the prior art in order to convert the kinetic energy of a flowing medium such as water or wind into usable energy, in particular into electricity.

Usually wind turbines are used, which can be divided into two main types of construction:
In practice, almost exclusively encountered are wind turbines with an approximately horizontal rotor shaft, which is approximately parallel to the wind direction during operation. This embodiment is already widely used, commercial application and is therefore well known. Most of these are high towers with large wind turbines, usually with three or more rotor blades. In order to set these wind turbines in motion, it usually requires higher wind speeds, so that you find such wind turbines often built near the coast or at higher altitudes. These wind turbines are constructive and control technology very expensive and expensive. The wind turbine must be constantly adapted to the irregular wind conditions. Thus, the rotor shaft must always be tracked to the current wind direction, and the angle of attack of the rotor blades depends on the current wind speed or speed. If the wind is too strong, the wind turbine must even be switched off and then provides no electricity. The generator, which is to convert the registered wind energy into electricity, must be accommodated due to the horizontal rotor shaft in a complex engine house, which is mounted at a dizzy height at the end of the mast behind the blade hub. In order to stabilize such a large mass at such a height, the tower must be made very solid. The maintenance is extremely expensive, because all work on the wind turbine must take place at a height of about 100 m above the surface, or even above the sea level, if the system is operated off-shore. Finally, a direct operation by the end user, as he is certainly found in solar panels, for example. On the roof of a family home to supply the family in question with solar power, is currently not practiced in wind turbines.

As part of a second variant of wind turbines, the rotor blades are arranged on a wind turbine rotating about a vertical axis, for example; There, therefore, the wind turbine rotates about an axis perpendicular to the wind direction. This has, for example, the advantage that the generator does not have to be installed at the top of the tower in a nacelle. Instead, with these wind turbines, the generator can be mounted on the ground and driven directly by the vertical shaft. Therefore, the tower or mast could be designed much weaker than the other wind turbine type, to filigree, affordable for the consumer constructions. Although always at least one driving rotor blade is flown by the wind; at the same time but unfortunately also at least one rotor blade opposite this, which acts as a brake on the rotor shaft as a result of the wind force.

In the WO 03/014 565 A1 For this reason, a wind turbine with a vertical rotor axis and with four rotor blades has already been described, two rotor blades each being arranged opposite one another and being coupled to one another in a rotationally fixed manner, offset at an angle of 90 °. Although it is always braked together with a driving rotor blade at the same time this opposite rotor blade. To mitigate this, therefore, these mutually opposite rotor blades are coupled together, namely by a common pivot axis approximately in the direction of the two rotor blade longitudinal axes. Will it be the driving rotor blade flows against the wind, so its base can align parallel to the vertical axis; However, it is prevented by means of a stop element from continuing to turn over. The surface of the opposing rotor blade is aligned as a result of the coupling exactly perpendicular to the first page level and is so taken to avoid a braking effect from the wind. Although the stop elements used in this case provide a constructionally simple solution for optimal use of wind energy through the wind turbine, however, make the stop elements or to those unbraked striking rotor blades during operation of the wind turbine extreme vibrations of the wind turbine, which burdens the entire construction to a considerable extent and Therefore, an immense reinforcement of the same makes necessary. In addition, bothering noises are generated each time for humans and animals.

The WO 2010/134 932 A1 discloses another arrangement of rotor blades which extend to and whose rotation is also limited by stop members. The construction described here is subject to the same disadvantages as for the WO 03/014 565 A1 ,

From the disadvantages of the described prior art, the invention initiates the problem of developing a generic flow power plant such that two opposing rotor blades are coupled together and staggered against each other by a simple low-cost construction that a braking rotor blade is taken out of the wind, without that this vibration or other negative properties for the wind turbine go along.

The solution to this problem is achieved in that the adjustment of at least two rotatably coupled rotor blades around their respective axis of rotation during its operation is not limited by stop elements.

The inventor has recognized that the permanent impact of the rotor blades on the stop elements provided for this purpose is ultimately responsible for a significantly reduced service life. By eliminating these previously necessary in such constructions elements it is possible to avoid strong vibration inducing non-linearities. The inventor has replaced the mode of action of the previously related stop elements by a special arrangement of the rotor blades, which also counteracts unwanted flashover of the rotor blades, but far less detrimental to the overall design, since the hard motion change is eliminated and by a gentle deceleration of the rotor blades in front of a Rollover of the same is replaced. The rotor of a wind turbine according to the invention has a large starting torque and in relation to conventional rotors with an approximately horizontal rotor axis a smaller nominal) speed and can thus be classified as a slow-speed. In addition, a wind turbine according to the invention can be constructed considerably more space-saving and technically simpler and thus cheaper. Because of this, it is u. a. also for smaller systems, eg. On private rooftops od. Like.

It has proved favorable that the adjustment angle of at least two rotor blades coupled to one another in a rotationally fixed manner about their respective axis of rotation is greater than 100 °, preferably greater than 120 °, in particular greater than 140 °. Thus, a slight overshoot of a rotor blade on the desired maximum deflection is possible, d. h., the mechanism has enough opportunity to shut down the rotor blade on a finally braking distance.

From a design point of view, the adjustment angle of at least two rotor blades rotatably coupled to one another about their respective axis of rotation can also be unlimited. The actual finite adjustment of the rotatably coupled rotor blades together does not result in that the rotation of the rotor blades would be limited by stop elements to achieve swinging out of a rotor blade from the wind, but this is the balance of all forces acting on the respective pair of coupled rotor blades forces and torque left. An advantageous interaction of these forces and torques can be achieved structurally in that by a suitable choice of the pivot axis about which a rotor blade can pivot, for example. Not by the center of gravity of the rotor blade concerned, but past it, so that in the center of gravity acting forces a torque develop, like a crank. If the wind pressure then influences the construction, then one rotor blade surface deflects under leeward wind pressure, aligning it approximately parallel to the vertical rotor axis and then providing a maximum wind attack surface, while the other rotor blade coupled to it rotates in an approximately horizontal position and thus offers only a minimal wind attack surface. This position is the more stable, the stronger the wind pressure, and therefore it does not cause a rollover of the rotor blades and thus not to disturbing braking effects or instabilities. The stable rotor blade position is in calm wind with a symmetrical arrangement of the coupled rotor blades, each rotor blade surface is oriented at an angle of approximately 45 ° to the horizontal; At the same time the potential energy of the system is minimal. At im Wind rotating Winrad splits this stable position in two different stable rotor blade positions, depending on which rotor blade is currently rotating in the wind direction, and there is a constant change between these two rotor blade positions. Nevertheless, there is no disturbing noise during operation due to the lack of stop elements in this change; Rather, the reversal of a stable rotor blade position in the other is extremely gentle, with an overshoot is quite possible.

The common center of gravity of two rotor blades coupled together is in a state free of external forces at a lower level than the bearing of the axes of rotation of the coupled rotor blades. When there is no wind, the two rotor blades are thus in a stable central position in a 45 ° arrangement, wherein the two rotor blades are in intersecting planes, which are each inclined by about 45 ° relative to the horizontal. Assuming that the two rotor blades in their center of gravity - with respect to the respective rotor blade axis b - each have an eccentricity e, so their common center of gravity is at neutral center position at the lowest point, ie at e · 2 ^-½ . Due to the pivoting on a circular path around the rotor blade axis b , the weight force at the first deflection from this neutral position does not yet provide a counterforce - therefore, even with a slightest wind, a torque-increasing pivoting of the rotor blades will already be used. As soon as a rotor blade pair is pivoted through 45 °, it achieves a locally stable adjustment, in which the wind torque goes to zero and in a further pivoting would even reverse, because now the impinged rotor blade has evaded the furthest to the rear. When rotated by 45 °, the common center of gravity has still not reached the height of the rotor blade axis b , but is still about a value e · 2 ^-3/2 ≈ e / 3 below. This value is therefore the maximum lever with which the weight exerts a restoring moment on the rotor blade pair.

For all embodiments of the device according to the invention it has proved to be advantageous if the longitudinal axis q of a cross section through a rotor blade in its centroid and along a plane b, the leaf axis b in question does not cut perpendicular to the respective blade axis, but at a distance a> 0, for example, under the eccentricity e> 0 of the center of gravity of a rotor blade with respect to its blade axis b , passing it. This means that the so-called centroid, where most of the wind pressure point is assumed, so where the maximum energy of the wind acts on the rotor blade, not on the so-called leaf axis b , the rotor blade axis of rotation, but so far away from the eccentricity e, so that both the wind pressure and the weight force are able to effect on a single rotor blade a torque about the Blattverstellachse b .

It is within the scope of the invention that the absolute value distance e, ie the eccentricity of the center of gravity of a rotor blade with respect to its pivot axis b , is equal to or greater than the thickness d of the rotor blade in the region of the centroid: e ≥ d, preferably twice as large or greater: e ≥ 2d, in particular three times as large or larger: e ≥ 3d. The larger the distance e is chosen, the stronger the torque developing under the influence of external forces, and the higher the stability of a deflected rotor blade condition.

The generated wind force F _{W1 of} a rotor blade turned into the wind is F _W1 = W _D · A · sin (δ + 45 °), where W _{D is} the wind pressure and A is the main surface of a rotor blade vane and δ is the angle about which a rotor blade pair respectively is deflected from the neutral middle position. At the same time, the wind force F _W2 of the other rotor blade of the same pair decreases according to F _W2 = W _D * A * cos (δ + 45 °), ie goes to zero, so that at the maximum deflection up to the locally stable point the total wind force It is determined that F _W = F _W1 = W _D × A × sin (δ + 45 °). The wind pressure W _D is determined as to W _D = (s - wL) ² · c _p · ρ _air / ^2, where l is the distance of the wind pressure point from the vertical axis of the rotor, c _p is a dimensionless pressure coefficient, of between 0 and 1, usually closer to 1, and ρ _{air is} the density of air (under normal conditions, ie at atmospheric pressure). The term s - ωl takes into account the difference between wind speed s and Bewegungsgeschweindigkeit ωl the wind pressure point. Since the speed of the wind turbine increases with the wind speed, this difference can be considered substantially independent of the wind speed. Therefore, one can essentially state: F _W = k · A · ρ _air .

At the same time, the following applies to the restoring weight force: F _G = G = m · g, where m is the mass of the rotor blade pair and g is the acceleration due to gravity.

A balance is established between the deflecting wind torque M _W and the restoring weight torque M _G : M _W = M _G , or F _W × h _W = F _G × h _W , with the respective levers h _W , h _G.

Since the weight consistently points vertically down, the wind power, however, constantly about is horizontally oriented, the levers h _W , h _G depend on the respective displacement δ: h _W = h _W (δ), h _G = h _G (δ). Although the wind power lever h _W decreases at a deflection 0 ° up to 45 ° from the value e to about zero; but on the other hand, but the weight of the lever at the same time between a deflection of 0 ° and 45 ° starting from zero slowly increases, and only up to about e / 3, always sets a balance, with an impinged rotor blade almost into a vertical position of its main surface is pivoted.

In order to raise this point as far as possible and thus give the wind turbine optimal efficiency, the weight of the rotor blades (without the rotor blade axis, which does not change their position) should be as low as possible, for example by choosing: ρ _sheet ≤ K · ρ _air , where K = 10 or K = 6 or K = 3.

Here, ρ _{sheet is} defined as the gross weight G _{B of} a rotor blade (but without its axis of rotation), divided by its gross volume (that is, the volume V _B enclosed by the shell of the rotor blade: ρ _sheet = G _B / V _B.

The exact dimensions of the rotor blade thus arise on the one hand depending on the above-described distance e and, of course, depending on the desired application and the material used, as well as the wing geometry. In the simplest case can be used for the rotors wood, plastic, metal, fiberglass or cardboard, composite material or sandwich construction is suitable.

The above boundary condition with respect to the density ρ _{blade of} a rotor blade to achieve optimum efficiency can be achieved, for example, by special rotor blade geometries, in particular by the rotor blades being hollow, and / or by using light materials such as plastic, and possibly also by a sandwich construction ,

In any case, the material used must be weatherproof and have sufficient rigidity to withstand the wind loads occurring. The geometry can z. B. square, triangular possibly also be curved, preferably simply curved around a curvature axis parallel to the blade longitudinal axis. In any case, the cross section of a rotor blade should be designed aorodynamic. The desired force game - that in the wind places a rotor blade rotating with the wind direction and the out of the wind swinging a rotor blade moving counter to the wind direction - depends on a suitable choice of the cross-sectional shape of the rotor blades.

It is first thought of the typical cross-section of a wing, whose profile is rounded at its front edge, on the other hand ends at its rear edge in a relatively sharp edge. This profile can be used in the invention so that when taken out of the wind rotor blade - which thus moves just against the wind direction and is pivoted in an approximately horizontal plane - the rounded edge in the direction of rotation runs ahead and the sharp edge follows. Further, the profile may be more or less curved, in particular along a curved about the pivot axis of the rotor blade concerned line. The rotor blade receives about the shape of a billowing sail, in which catch the wind very well and this then swing in front of him and thereby put in the wind.

In addition, the pivoting of a pair of rotor blades under the influence of wind can be promoted by a special design of the rotor blade geometry still worthier. For example. For example, a profile section in the region of a longitudinal edge of the rotor blade can bend or bend from the approximately tangential or curved orientation about the pivot axis into a more radial orientation. In the case of the "rearward", preferably pointed edge, this could be a bend radially outward, in which the wind can catch well even in the neutral position of the rotor blade in order to deflect it; in the case of the "front", preferably rounded edge, such a bend should take place radially inwards, ie toward the pivot or blade axis, whereby a kind of pocket is formed in which the wind can also catch.

However, even in a main surface of the rotor blade itself, preferably at that side of the rotor blade facing the pivot axis or blade axis, such a pocket can be formed, for example by the region of the rotor blade being tapered in regions. In this case, the front edge of such a bag in the direction of rotation may be formed as a cross-section backward tip, while the rear edge region of such a bag, for example, gently swings up to the rear edge and there opens in the above already indicated, sharp edge. Such a highly asymmetric pocket also allows additional uptake of wind energy and therefore can reduce the wind speed needed for a launch.

This results in a further basic principle of the invention that a rotor blade, in particular its cross-section, is asymmetrical to a plane of the respective blade axis b together with The longitudinal axis of the respective arm is clamped. The advantage is that the rotor starts even at very low wind load and you can generate energy even with little wind.

The invention further provides that the longitudinal axis l of a rotor blade does not intersect or not perpendicularly intersect the rotor axis r . In any case, the two longitudinal axes of the rotor axis l can not r or never simultaneously cut at a right angle on both blades of a pair through a common rotor blade axis b drehbewglich mutually coupled rotor blades. For a right-angled cutting of a rotor blade longitudinal axis l and the rotor axis r comes for each rotor blade due to its eccentricity in the wind pressure point - if any - anyway only at a single pivot angle α selectively considered, and since the pivot angle α coupled rotor blades yes so to speak in the opposite direction, such singular points can never be achieved simultaneously.

It is within the scope of the invention that the surface normal n of a rotor blade intersects in the centroid of the relevant leaf axis b or passes closer to that than the longitudinal axis q of the cross section through the rotor blade in its centroid, ie at a distance e _w , where: e _w <e.

If this surface normal n intersects the blade axis b , then the stable point, which occurs under the influence of the wind pressure, is reached when this surface normal n is oriented parallel to the wind direction s , hence the rotor blade in question has completely turned into the wind and This provides maximum resistance.

On the other hand, the invention undergoes an advantageous development in that the absolute value distance e _w at which the surface normal n of a rotor blade passes in its centroid on the relevant blade axis b is equal to or greater than one-tenth of the width b of the rotor blade in the region of the centroid: e _w ≥ 0.1 · b, preferably equal to two tenths of the width b or greater: e _w ≥ 0.2 · b, in particular equal to three tenths of the width b or greater: e _w ≥ 0.3 · b. Preferably, the surface normal n of a rotor blade runs in its centroid thereby below the relevant blade axis b therethrough. This has the consequence that the rotor blade, despite its weight can easily put in a completely veritkale level and thus can build up a maximum wind pressure, which is why an optimal efficiency can be achieved.

In a wind-induced rotation of the rotor about the rotor axis r with the angular velocity ω, the wind pressure point of a wind turbine blade, for which preferably b · ( s × ω )> 0, precedes the relevant blade axis b and lies thereby leeseits the same. For this reason, for a pivoting of the rotor blade from the respective stable point whose wind pressure point would have to swivel against the wind pressure to windward, which would be energetically unfavorable.

Finally, it is in accordance with the teaching of the invention that, in the case of wind-induced rotation of the rotor about the rotor axis r at the angular velocity ω, the center of gravity of a rotor blade taken out of the wind, for which b · ( s × ω ) <0, is below the concerned leaf axis b is located. Therefore, for a pivoting of the rotor blade from the respective stable point whose center of gravity would pivot against the weight upwards, which would be energetically unfavorable.

This distribution according to the invention of the flat centers of gravity ensures that the desired adjustment of the rotor blades takes place without any mechanical stop elements solely as a result of a separate energy optimization; in the course of its rotation about the rotor axis, each rotor blade makes a transition from the movement with the wind to a movement against the wind and vice versa; In the area of these transitions, the effect of wind energy is eliminated, and each pair of rotor blades coupled together automatically falls back into a symmetrical position, with the crossed rotor blade main planes each offset by 45 ° from the horizontal.

Further features, details, advantages and effects on the basis of the invention will become apparent from the following description of a preferred embodiment of the invention and from the drawing. Hereby shows:

1 a perspective view of the rotor of a flow power plant according to a first embodiment of the invention;

2 a plan view of the rotor after 1 ;

3 a vertical section through the 2 along the line III-III;

4a . 4b Cuts through the 3 along the line IV-IV, respectively at different positions of the cut rotor blades with respect to the wind direction;

5 a perspective view of the rotor of a flow power plant according to a second embodiment of the invention;

6 a plan view of the rotor after 5 ;

7 a vertical section through the 6 along the line VII-VII;

8th a the 2 and 6 corresponding plan view of the rotor of a again modified embodiment of the invention, partially broken off;

9 a side view of the rotor 8th after complete removal of a rotor blade pair;

10 one of the 8th corresponding representation of the rotor of a modified embodiment of the invention again;

11 a side view of the rotor 10 after removal of a rotor blade pair;

12 a side view of yet another embodiment of the invention, after removal of a pair of rotor blades and partially cut;

13 a horizontal section through the 12 along the line XIII-XIII, partially broken off;

14 one of the 13 corresponding representation of another embodiment of the invention;

15 a side view on 14 , also canceled; such as

16 one of the 14 corresponding representation of yet another embodiment of the invention.

A first embodiment of a flow force plant according to the invention 1 is in 1 played. On the upper end of an approximately vertical mast 2 there is a rotor 3 that is on top of a vertical rotary shaft 4 is attached and together with that in the mast 2 around its vertical axis 5 is rotatably mounted.

The rotor 3 is by four approximately radially from that away aspiring rotor blades 6 to a windmill 7 , The rotor blades 6 are always arranged in pairs; On the one hand, it should be at least two pairs, since otherwise an automatic start is not secured, and on the other hand at most three pairs, because otherwise the successive rotor blades 6 dispute each other's wind.

In 1 are two pairs of two diametrically opposed rotor blades 6 available. In each case two diametrically opposite arranged rotor blades 6 are rigidly connected to each other, for example. By a plurality of rod-shaped sections 8th . 9 . 10 ,

At the flow power plant 1 to 1 These are rod-shaped sections 8th . 9 . 10 in the manner of a crankshaft bent several times 11 interconnected.

The middle, straight part 8th the crankshaft 11 is in its middle or, more accurately, in the rotor 3 around its longitudinal axis 12 rotatably mounted. This longitudinal axis 12 acts as a pivot axis for the entire rotor blade pair 6 , From this central section 8th the crankshaft branches off at both ends one arm each 9 approximately radially to the longitudinal axis 12 to the outside, but at both ends in different directions. Because the two arms 9 are not parallel to each other, but their projections along the longitudinal axis 12 to the common storage point 13 close there an angle α with an amount of 90 ° with each other. However, this angle α is not chosen arbitrarily, but depends on the preferred direction of rotation ω of the rotor 3 From: It turns out that the offset angle α, which when looking at one end of the Längsache 12 from the front arm in the direction of view 9 to the rear arm in the direction of view 9 is to be measured, each having the opposite direction of rotation as the preferred direction of rotation ω of the rotor 3 viewed in the vertical direction from top to bottom - if ω is, for example, clockwise, then α must be used as levorotatory; on the other hand, if ω is left-handed, α is clockwise. At the free ends of the jewels equal long arms 9 These are each in the form of a respective peripheral axis section 10 away from the arm in question 9 antiparallel to the central section 8th strives away, but laterally about the length of said arm 9 from the middle intercept 8th added. These peripere shaft sections 10 turn in the form of the rotor blades 6 and form approximately their longitudinal axes. The peripheral axis sections 10 can be about the extension of the blade axes of the respective rotor blades 6 form and can for the purpose of rigid connection in a blind hole on the inner end face of the rotor blade concerned 6 let in and be fixed there.

How to get out 1 can refer to the total of 2p rotor blades 6 (p = number of rotor blade pairs) against each other a first rotor blade 6a (where k = 1 is calculated) has an offset of approximately (k-1) x 180 ° / p, where k = 1, 2, ... (2p). This means for the illustrated case of two pairs of rotor blades (p = 2) that the rotor blades 6a . 6b . 6c . 6d have an offset of about (k-1) x 180 ° / 2 + β = (k-1) x 90 ° + β with respect to the wind, where k = 1, 2, 3, 4 and where β is the angle between the Wind direction s and the first rotor blade 6a corresponds; the rotor blades 6 _m can be assigned to the values k over m _k , for example k = 1: m ₁ = a; k = 2: m ₂ = b; k = 3: m ₃ = c; and k = 4: m ₄ = d. With three rotor blade pairs (p = 3), the rotor blades 6 _m have an offset of approximately (k-1). 180 ° / 3 + β = (k-1) .60 ° + β with respect to the wind s , where k = 1 , 2, 3, 4, 5, 6 or m _k = a, b, c, d, e, f. Furthermore, for the angular velocity ω of the rotor 3 : ω = dβ / dt.

The rotor 3 is in 1 shown in a wind direction from the right front, recognizable by the flow arrows s ; In contrast, the four rotor blades 6 just reproduced at the moment, with the pivot axis 12 a pair of rotor blades parellel to the wind direction s , the pivot axis 12 of the other rotor blade pair perpendicular to it. In this case, α = 90 °, since the longitudinal axis l _{1 of} the rotor blade 6a with the wind direction s an angle of 90 °.

Due to the rotation ω of the wind turbine 11 the rotor blade moves 6a left front straight with the wind or in the wind direction s , the rotor blade 6c right in the reverse direction, and the two remaining rotor blades 6b . 6d each move perpendicular to the wind direction s .

The rotor blades 6 preferably have a flat, elongated shape, wherein the respective longitudinal axis 14 in the radial direction from the vertical axis 5 extends away. The base of a rotor blade 6 can, seen in the radial direction from the inside to the outside, widen or even rejuvenate or remain constant. The rotor blades preferably have 6 each an aerodynamic cross-sectional shape similar to an aircraft wing, in particular with a concavely curved main surface 15 , which in the driving rotor blade 6a facing the wind, that is lying in windward position, and with a convexly curved main surface 16 , which leeseits of the driving rotor blade 6a lies. Because the main planes of the remaining three rotor blades 6b . 6c . 6d are approximately parallel to the wind direction s , they each take only a small wind pressure with their respective edge facing the wind and therefore either have no effect on the rotational speed ω as the rotor blades 6b . 6d or only a very small one like the rotor blade 6c ,

So it's according to 1 a rotor blade 6a turned up to the wind at maximum, and thus optimally absorbs its wind pressure force and places it in an accelerating rotary drive of the wind turbine 7 around. That by pivoting about the horizontal axis 12 taken from the wind rotor blade 6c For example, is in a position where the captured by this wind pressure force is minimal, and with this also a possibly starting from this against the wind rotor blade 6 generated braking effect. The two rotor blades 6b . 6d in the direction of rotation immediately before and behind the wind catching and the wind turbine 7 Rotating driving rotor blade 6a do not feel the wind pressure or only in the direction of its pivot axis 12 in which they are not sensitive to external wind forces.

Due to the angular offset of their main planes of about 90 ° to each other take these two rotor blades 6b . 6d in the rotational position according to 1 a stable in windless position, in which both rotor blades 6b . 6d are deflected only by about 45 ° relative to the horizontal. This position of the minimum potential energy is also particularly clear in the 2 , In 4b is also the - automatic - alignment of the rotor blades 6b . 6d shown in calm or at the transition from the driving angle of rotation range, where the wind pressure in the direction of the respective pivot axis 12 acts and therefore no influence on the position of the respective rotor blades 6b . 6d Has.

That of the each put into the wind rotor blade 6a powered wind turbine 7 is over his rotor 3 and the vertical rotation shaft 4 rotatably connected to an input terminal of a provided at the foot of the structure generator to drive it and generate electricity in this way.

In the construction according to the invention, neither the center of gravity of the rotor blade concerned is 6 nor its main attack point of the captured wind on the pivot axis 12 of the relevant rotor blade 6 or rotor blade pair. Rather, clarifies 3 in that the main point of attack of the wind is at the so-called wind pressure point 17 a wind-turned rotor blade 6a located, and at a distance e _w below the pivot axis 12 of the relevant rotor blade 6a , as in 3 shown on the left. In 3 on the right it can be seen that due to the cranked crankshaft 11 also the main plane of a rotor blade 6 a distance e to the relevant rotor blade pivot axis 12 having. Especially in the area of the wind pressure point 17 a rotor blade has a thickness d measured perpendicular to its major surface; in particular: e> d as well as e> e _w .

Because the pivot axis 12 an end of an arm 9 the crankshaft 11 interspersed, the respective longitudinal direction 14 of the relevant rotor blade 6 the other end of the arm 9 , can be determined by the effective length of the arms 9 the distance e between blade longitudinal direction 14 and blade pivot axis 12 set or specify. The larger this distance e is, the more stable are those in 4a reproduced end positions of the wind turbine rotor blade 6a and the wind blade taken out of the wind 6c according to 4a ,

Alternative embodiments of the flow force plant according to the invention 1 are in the 5 et seq , played.

There are the swivel axes 12 ' not designed as a multi-headed crankshaft, but straight stretched. Nevertheless, in the wind pressure points 17 ' a leading offset of a rotor blade 6 ' in the direction of rotation relative to the respective pivot axis 12 ' to reach, are the longitudinal directions 14 ' the rotor blades 6 ' not parallel to the respective pivot axis 12 ' but cut them in an eccentric point and there are at a leading angle γ ≠ 0 relative to the pivot axis 12 ' hired; The main plane of a rotor blade 6 ' is approximately perpendicular to the respective pivot axis 12 ' and the longitudinal direction 14 ' of the relevant rotor blade 6 ' spanned level.

How to get out 6 can take, is under Windeinfluß the maximum Asked in the wind condition of the rotor blade 6a ' particularly stable, because its wind pressure point 17 ' is moved leeward at the maximum and therefore would have to move with each further pivoting against the wind pressure to windward, which is energetically unfavorable.

Out 7 st to take that in similar form thanks to the inclination of the rotor blades 6 ' the rotor blade just taken out of the wind 6c ' assumes a condition with the lowest possible center of gravity, which additionally has a stabilizing effect on this condition.

In the 8th and 9 is the windmill 7 '' with rotor 3 '' and rotor blades 6 '' another flow power plant 1'' shown.

This represents, as it were, a combination of the previously described embodiments 1 and 1' Here there is on the one hand a crankshaft 11 '' with respect to a central intercept 11 '' cranked arms 9 '' as in 1 but with the adjoining peripheral intercepts 10 '' not parallel to the middle intercept 11 '' or to the pivot axis 12 '' run, but by an angle γ ≠ 0 are employed in contrast. In the embodiment 1'' this angle γ is oriented such that the resulting offset of the wind pressure point 17 '' opposite the pivot axis 12 '' to that from the length of the arm 9 '' the crankshaft 11 '' resulting offset adds and thus the in 9 reproduced rotor blade positions are particularly stable in wind. The center of gravity of a wind blade placed in the wind 6a '' again lies below the pivot axis 12 '' ,

In contrast, the flow power plant differs 1 ⁽³⁾ of the last described flow power plant 1'' in that there the angle γ is oriented differently, in such a way that the resulting offset from that of the length of the arm 9 ⁽³⁾ the crankshaft 11 ⁽³⁾ subtracts the resulting offset. Nevertheless, the arrangement should be made such that the end position is stable in wind. This can also be produced, inter alia, by the center of gravity of a rotor blade taken out of the wind 6c ^{(3) is} particularly deep.

All described embodiments 1 . 1' . 1'' . 1 ^{(3) has in} common is that all get along without the use of stop elements and instead lead to an energetically optimized alignment in the wind. The automatic alignment of the rotor blades 6 . 6 ' . 6 '' . 6 ⁽³⁾ is determined solely by the position of the center of gravity, the position of the wind pressure point and the shape of the blade; the specification of these factors and the consequent interaction of wind and weight forces ensures that only the currently driving rotor blade 6a . 6a ' . 6a '' . 6a ⁽³⁾ is pivoted maximally in the wind, ie with the normal n to its main plane in the wind pressure point approximately parallel to the wind direction s, while the opposite rotor blade 6c . 6c ' . 6c '' . 6c ^{(3) is} largely taken out of the wind and thus exerts only a minimal braking torque; the other rotor blades 6b . 6d ; 6b ' . 6d '; 6b '' . 6d ''; 6b ⁽³⁾ , 6d ⁽³⁾ do not affect the speed of the wind turbine 7 . 7 ' . 7 '' . 7 ⁽³⁾ off.

The inventive construction of a flow power plant 1 with vertical axis of rotation 5 of the windmill 7 brings with it the advantage that also several wind turbines 7a . 7b . 7c tower-like can be arranged one above the other, as from 12 seen.

In this case, the rotor 3a . 3b . 3c every windmill 7a . 7b . 7c at the upper end of its own rotary shaft 4a . 4b . 4c be attached. Except for the rotary shaft 4a the top wind turbine 7a are the remaining rotary shafts 4b . 4c formed hollow and coaxial and concentric with each other and extend from the respective rotor 3a . 3b . 3c down, for example, each with its own generator. As a result, there is only one mast or tower 18 required, namely for the storage of the outermost rotary shaft 4c while the inner rotary waves 4b . 4a in the respective outer rotary shaft 4c . 4b are stored. An advantage of such an arrangement is that the windmills 7a . 7b . 7c run independently of each other and each can drive their own generator, or they can - for example, in low wind - are switched to a common generator and then drive it together.

However, such a tower-like multiple arrangement requires a special support of the pivot axes 12a . 12b . 12c the wind wheels 7a . 7b . 7c because only the pivot axes 12a of the uppermost rotor 3a the vertical axis 5 right through, but not the others.

For the rotors underneath 3b . 3c On the other hand, other solutions for the rotationally fixed coupling of the two rotor blades 6 a couple are chosen. Examples show that 13 to 16 :
The simplest construction shows 13 , Here enforce the pivot axes 12 the relevant rotor 3 eccentric, ie at a distance from the center of the vertical axis 5 or the rotating shafts running along there 4 , However, a slight imbalance could occur here, but it could be tried out by suitably applied counterweights; In addition, the rotational speed ω is generally not too large, so that a possible imbalance does not have too great consequences.

at 14 are the rotor blades 6 to a hanger 19 connected to the inner rotary shafts 4 encircles the outside about U-shaped. This temple 19 can by means of pins 20 in designated holes 21 on the outside of the relevant rotor 3 be stored. To balance the weight distribution and to avoid imbalances should be on the bracket 19 a similar bracket 19 ' be mounted on the diametrically opposite side. The 15 shows that even with this arrangement, no stop is effective, but the / the bracket 19 . 19 ' is / are made so large that they during normal operation of the wind turbine 7 not on the rotor 3 nudge.

The most technically complex version shows 16 , Here are the mounting rods or pipes 22 both rotor blades 6 each with two axially staggered gears 23 . 24 provided inside a housing 25 can rotate freely. On the actual rotor 3 are diametrically opposed holes 26 for storage of two other gears 27 provided, each with a gear 23 . 24 every rotor blade 6 comb. Through the interlocking gears of the gears 23 . 24 . 27 are the mounting rods or pipes 22 both rotor blades 6 rotatably coupled to each other, although they are not directly connected and also the vertical area, where the remaining rotating shafts 4 run along, not pierced.

In all previously described embodiments of the device according to the invention 1 . 1' . 1'' . 1 ⁽³⁾ an energetically optimal alignment of each respectively associated rotor blade pairs is achieved by the wind without any stop elements. This is achieved, inter alia, in that the longitudinal axes 1 of the rotor blades do not intersect the rotor axis r perpendicularly or not perpendicularly.

LIST OF REFERENCE NUMBERS

1

Flow turbine

2

mast

3

rotor

4

rotary shaft

5

vertical axis

6

rotor blade

7

windmill

8th

middle intercept

9

poor

10

peripheral axis section

11

crankshaft

12

longitudinal axis

13

storage point

14

longitudinal axis

15

concave main surface

16

convex main surface

17

Wind pressure point

18

tower

19

hanger

20

spigot

21

drilling

22

mounting rod

23

gear

24

gear

25

casing

26

drilling

27

gear

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 03/014565 A1 [0006, 0007]
• WO 2010/134932 A1 [0007]

Claims (14)

Flow power plant ( 1 ; 1'; 1''; 1 ⁽³⁾ ), in particular a wind turbine, with a plurality of flat sheets ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ) having rotor ( 3 ) which is rotatably mounted about a rotor axis r , which is not parallel to the flow direction s , but preferably approximately perpendicular thereto, wherein the rotor blades ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ) in each case have major surfaces which strive away from the rotor axis r and are each rotatable about a blade axis b , and wherein in each case two rotor blades ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ) are offset by a center angle of about 180 ° about the rotor axis r against each other, such that their blade axes b ₁ , b ₂ in the direction of the respectively coupled rotor blade ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ), and wherein the respective rotor blades ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ) are rotatably coupled to each other, such that the directions of the longitudinal axes q ₁ , q _{2 of} their cross sections are rotated at an equal distance from the rotor axis r by an angle of about 90 ° to each other, characterized in that the adjustment of at least two rotationally fixed rotor blades coupled together ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ) is not limited by their respective axis of rotation during its operation by stop elements. Flow power plant ( 1 ; 1'; 1''; 1 ⁽³⁾ ) according to claim 1, characterized in that the displacement of at least two rotatably coupled together rotor blades ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ) is about their respective axis of rotation greater than 100 °, preferably greater than 120 °, in particular greater than 140 °. Flow power plant ( 1 ; 1'; 1''; 1 ⁽³⁾ ) according to claim 1 or 2, characterized in that the displacement of at least two rotatably coupled together rotor blades ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ) around their respective axis of rotation is unlimited. Flow power plant ( 1 ; 1'; 1''; 1 ⁽³⁾ ) according to one of claims 1 to 3, characterized in that a rotor blade ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ) is formed as easily as possible, in particular such that the following applies to its gross density ρ _sheet : ρ _sheet ≤ K · ρ _air , where K = 10 or K = 6 or K = 3, where ρ _{sheet is} defined by the gross weight G _{B of} a rotor blade ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ), divided by its gross volume, that of the shell of the rotor blade ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ) enclosed volume V _B. Flow power plant ( 1 ; 1'; 1''; 1 ⁽³⁾ ) according to any one of the preceding claims, characterized in that the common center of gravity of two mutually coupled rotor blades ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ) is in a state free of external forces at a lower level than the bearing of the axes of rotation of the rotor blades coupled together ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ). Flow power plant ( 1 ; 1'; 1''; 1 ⁽³⁾ ) according to one of the preceding claims, characterized in that the longitudinal axis l of a rotor blade ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ) in its position when free of external forces state the rotor axis r is not or not perpendicular cuts. Flow power plant ( 1 ; 1'; 1''; 1 ⁽³⁾ ) according to any one of the preceding claims, characterized in that the longitudinal axis q of a cross section through a rotor blade ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ) in its centroid and along a plane perpendicular to the relevant leaf axis b, the respective leaf axis b does not intersect, but at a distance e> 0 past that. Flow power plant ( 1 ; 1'; 1''; 1 ⁽³⁾ ) according to claim 7, characterized in that the absolute value distance e is equal to or greater than the thickness d of the rotor blade ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ) in the area of the centroid: e ≥ d, preferably twice as large or larger: e ≥ 2d, in particular three times as large or larger: e ≥ 3d. Flow power plant ( 1 ; 1'; 1''; 1 ⁽³⁾ ) according to any one of the preceding claims, characterized in that the surface normal n of a rotor blade ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ) in whose centroid the respective leaf axis b intersects or passes closer to that leaf axis than the longitudinal axis q of the cross section through the rotor blade (FIG. 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ) in its centroid, ie at a distance e _w , where: e _w <e. Flow power plant ( 1 ; 1'; 1''; 1 ⁽³⁾ ) according to any one of the preceding claims, characterized in that the absolute value distance e _w , below which the surface normal n of a rotor blade ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ) in the centroid of the respective leaf axis b passes, equal to or greater than one-tenth of the width b of the rotor blade ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ) in the area of the centroid: e _w ≥ 0.1 · b, preferably equal to two tenths of the width b or greater: e ≥ 0.2 · b, in particular equal to three tenths of the width b or greater: e _w ≥ 0 3 · b. Flow power plant ( 1 ; 1'; 1''; 1 ⁽³⁾ ) according to any one of the preceding claims, characterized in that a rotor blade, in particular its cross-section, is asymmetrical to a plane extending from the relevant blade axis b together with the longitudinal axis of the arm in question ( 11 ) is spanned. Flow power plant ( 1 ; 1'; 1''; 1 ⁽³⁾ ) according to any one of the preceding claims, characterized in that during a rotation of the rotor caused by the wind ( 3 ) about the rotor axis r with the angular velocity ω the wind pressure point of a wind turbine blade ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ), wherein preferably b * ( s × ω )> 0, leads the relevant blade axis b . Flow power plant ( 1 ; 1'; 1''; 1 ⁽³⁾ ) according to any one of the preceding claims, characterized in that during a rotation of the rotor caused by the wind ( 3 ) about the rotor axis r with the angular velocity ω the wind pressure point of a wind turbine blade ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ), wherein preferably b · ( s × ω )> 0, leeseits the respective leaf axis b lies. Flow power plant ( 1 ; 1'; 1''; 1 ⁽³⁾ ) according to any one of the preceding claims, characterized in that during a rotation of the rotor caused by the wind ( 3 ) about the rotor axis r at the angular velocity ω the center of gravity of a rotor blade taken from the wind ( 6a - 6d ; 6a ' - 6d '; 6a '' - 6d ''; 6a ⁽³⁾ - 6d ⁽³⁾ ), wherein preferably b · ( s × ω ) <0, lies below the relevant leaf axis b .

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