Rotor blade of a wind turbine comprising a lift changing device and method of mounting the same

Abstract

The invention relates to a rotor blade (10) of a wind turbine, comprising a lift-altering device (20) with at least one fluid injection module (21) and at least one source of compressed fluid (22), wherein the at least one fluid injection module (21) comprises a plurality of fluid injectors (23) which are fluidically connected to the at least one source of compressed fluid (22), wherein the at least one fluid injection module (21) is mounted as an add-on to an outer surface of a suction side (17) or a pressure side (18) of the rotor blade (10). The invention further relates to a method for mounting the rotor blade (10), wherein a rotor blade (10) is provided and the at least one fluid injection module (21) is mounted as an add-on to the outer surface of the suction side (17) or the pressure side (18) of the rotor blade (10).

Description

Technical Field

[0001] This invention relates to rotor blades of a wind turbine including a lift conversion device and methods for manufacturing / installing the same. Background Technology

[0002] Various types of flow control devices, such as lift modifiers, can be used in wind turbines. To achieve a given objective (such as increasing or decreasing the lift of the rotor blades), different desired aerodynamic characteristics can be achieved using flow control devices.

[0003] In active lift conversion devices, external energy is supplied to activate lift conversion. Such devices are known, for example, from EP 2998571 A1, and they offer the advantage of actively controlling the aerodynamic characteristics of the rotor blades. However, the installation and integration of lift conversion devices in wind turbines is quite complex.

[0004] Other active types of lift conversion devices are known, in which a fluid ejector in the form of an orifice is integrated into the housing. However, this requires drilling holes into the rotor blade housing and / or having a pressurized or vacuum vessel outside the rotor blade. This compromises the structural integrity of the rotor blade. Similarly, installing such a lift conversion device on existing rotor blades is very cumbersome. Summary of the Invention

[0005] The objective of this invention is to provide a rotor blade with an active type of lift conversion device and its associated manufacturing / installation method, wherein the lift conversion device is easy to install and its installation does not compromise the structural integrity of the rotor blade.

[0006] This objective is achieved through the subject matter of the claims. In particular, this objective is achieved through the rotor blade according to claim 1 and the method according to claim 14. Further details of the invention can be obtained from the other claims, as well as the specification and drawings. Thus, the features and details described in conjunction with the rotor blade of the invention are applicable to the method of the invention, and therefore the disclosures regarding various aspects of the invention are or can be cross-referenced.

[0007] According to a first aspect of the invention, the problem is solved by means of a rotor blade of a wind turbine, the rotor blade including a lift-changing device having at least one fluid injection module and at least one compressed fluid source, wherein the at least one fluid injection module includes a plurality of fluid injectors fluidly connected to the at least one compressed fluid source, wherein the at least one fluid injection module is mounted as an attachment to the outer surface of the suction side or pressure side of the rotor blade.

[0008] The at least one fluid jet module can be configured to generate a fluid curtain of separated airflow on the suction side or the pressure side of the rotor blade when the at least one compressed fluid source supplies compressed fluid to the at least one fluid jet module. For example, the fluid jet module can be placed along the entire spanwise extension of the blade, or only on the outer 50% of the blade. And regarding the chordwise position, it can be placed somewhere between 1% and 60% of the chord, preferably somewhere between 5% and 45% of the chord.

[0009] The lift-changing device according to a first aspect of the invention is of an active type. When the lift-changing device is activated, i.e., when compressed fluid is supplied from the at least one compressed fluid source to the plurality of fluid ejectors, the plurality of fluid ejectors jet the compressed fluid onto the outer surface of the rotor blades, thereby creating a fluid curtain of separated airflow on the suction or pressure side of the rotor blades. Therefore, the lift coefficient is reduced and the drag coefficient is increased. The fluid flow around the airfoil becomes stalled, and the aerodynamic load due to lift decreases, while the aerodynamic load due to drag increases.

[0010] The lift conversion device can be activated under operating or environmental conditions that benefit the wind turbine from these smaller lift loads and higher drag loads (such as shutdown processes, extreme gusts or turbulence, and pitch actuation). However, when the lift conversion device is not activated (i.e., deactivated), no compressed fluid is supplied to the multiple fluid ejectors, and the lift and drag coefficients are unaffected or minimally affected by the lift conversion device (in the case of adding the device to the blades). Thus, during normal operation of the wind turbine (i.e., in the absence of the aforementioned operating or environmental conditions), a large lift coefficient and a low drag coefficient can be maintained (e.g., due to the design of the rotor blades), allowing it to operate efficiently.

[0011] According to a first aspect of the invention, the at least one fluid injection module is mounted as an add-on to the outer surface of the suction side or the pressure side of the rotor blade. The fluid injection module is designed as a separate add-on device that can be installed on a new or existing wind turbine. Therefore, the at least one fluid injection module can be mounted on a new rotor blade or as an add-on to a used rotor blade for retrofitting. Thus, the fluid injection module is a separate unit from the rotor blade housing, or in other words, is not part of the rotor blade housing during manufacturing. Instead, the at least one fluid injection module is connected to the housing by mounting it to the rotor blade housing. The fluid injection module can be mounted to the outer surface of the suction side or the pressure side of the rotor blade, and its length extends in the longitudinal direction of the rotor blade.

[0012] The rotor blades may be provided with at least one fluid injection module on the suction side or pressure side of their airfoil. The at least one compressed fluid source must be operational, i.e., supplying compressed fluid to the at least one fluid injection module to change the lift of the rotor blades.

[0013] Unlike most existing lift-modifying devices that focus on enhancing the aerodynamics of airfoils, the proposed scheme achieves separation, or in other words, disruption of the airflow around the airfoil of the rotor blade, thereby simultaneously reducing the lift coefficient and increasing the drag coefficient. This separation of the airflow around the airfoil or outer surface of the rotor blade is achieved by actively generating a fluid curtain on the outer surface of the rotor blade, which can also be referred to as the primary flow. For this purpose, at least one fluid injection module of the lift-modifying device is mounted on the outer surface of the airfoil on the suction or pressure side of the rotor blade. Additional components of the lift-modifying device can be specifically arranged inside the rotor blade and / or the wind turbine.

[0014] In certain special circumstances, such as certain types of emergency shutdowns, it may be advantageous to place the at least one fluid injection module on the pressure side of the airfoil rather than on the suction side of the airfoil.

[0015] The fluid ejectors are specifically configured to communicate with the surrounding environment of the airfoil. The fluid ejectors are specifically oriented outward from the airfoil of the rotor blade. Compressed fluid is applied as a fluid curtain to the surrounding environment of the airfoil on the suction or pressure side of the airfoil. The fluid curtain can be described as a flow of compressed fluid ejected from the plurality of fluid ejectors. It may be provided that individual, most, or all of the plurality of fluid ejectors are linearly (in a straight line) or substantially linearly aligned. Thus, the fluid curtain can be generated along a straight or substantially straight line to separate the fluid flow on the suction or pressure side of the rotor blade by a straight or substantially straight fluid curtain.

[0016] The at least one compressed fluid source provides a compressed fluid, which can be at a pressure greater than atmospheric pressure. The compressed fluid source can be configured to supply the compressed fluid at a pressure of at least 200 kPa, particularly at least 1000 kPa. Therefore, the compressed fluid can be supplied at this pressure. However, the pressure at the fluid ejector can be lower because pressure is lost during its journey. The supplied compressed fluid can be, in particular, air, dry air, or any other inert gas.

[0017] Provided, the at least one fluid injection module is designed as a panel. The panel is relatively flat, i.e., has a small thickness, and is an elongated body with two large surfaces that are opposite to each other. Therefore, one of these two large surfaces can be configured to be easily mounted on the outer surface of the rotor blade. This large surface can correspond in shape to the portion of the outer surface where the at least one fluid injection module is to be mounted, thus achieving a good form fit. The opposite large surface is the surface of the at least one fluid injection module located on the airfoil of the rotor blade. It can have a curvature corresponding to the overall shape of the rotor blade at the portion of the outer surface where it is to be mounted.

[0018] Alternatively, the at least one fluid injection module may include a curved external shape on its outer side. This curved external shape may correspond to the airfoil shape of the rotor blade. Thus, when the at least one fluid injection module is arranged on the suction or pressure side of the rotor blade, a particularly aerodynamic design can be achieved.

[0019] Alternatively, the at least one fluid injection module may have a curved profile. This curved profile, as explained above, of a panel with two opposing large surfaces, allows the fluid injection module to conform to the shape of the outer surface of the rotor blades and provides good aerodynamic properties for the rotor blades at the location of the at least one fluid injection module.

[0020] Alternatively, the at least one fluid injection module can be mounted to the outer surface of the rotor blade by means of at least one adhesive, at least one tape, and / or a mechanical fastener. The mechanical fastener can be a screw, bolt, or the like. Different methods of mounting the at least one fluid injection module to the outer surface of the rotor blade achieve different advantages. An adhesive allows the at least one fluid injection module to attach very consistently to the outer surface of the rotor blade. Tape is easy to handle and allows for very simple installation. Mechanical fasteners allow for reversible installation, i.e., reversible without damaging the rotor blade housing or the at least one fluid injection module.

[0021] Therefore, it can be provided that the at least one fluid injection module is reversibly mounted on the outer surface of the rotor blade. Thus, if it is found that the at least one fluid injection module is more effective in different parts of the outer surface of the rotor blade, or if different lift changes are to be achieved by means of the at least one fluid injection module, the at least one fluid injection module can not only be easily removed from the rotor blade, but can also be rearranged.

[0022] Similarly, it can be provided that the at least one fluid injection module is embedded in a recess in the rotor blade housing. This means that the at least one fluid injection module is not simply attached to the outside of the rotor blade as an add-on, but is at least partially, and particularly completely, integrated into the rotor blade, and particularly into its housing. For this purpose, the rotor blade housing includes a recess in shape corresponding to the at least one fluid injection module. The at least one fluid injection module may be configured to be flush with the airfoil or housing of the rotor blade. Thus, the aerodynamic properties of the rotor blade, particularly the lift and drag coefficients, are maintained when the lift conversion device is not activated.

[0023] Furthermore, the at least one fluid injection module may include a fluid flow channel in fluid communication with the plurality of fluid injectors. The fluid flow channel may be fluidly connected to the at least one compressed fluid source via at least one fluid supply line. Thus, the fluid flow channel delivers compressed fluid from the at least one compressed fluid source to the plurality of fluid injectors.

[0024] It can be further provided that the plurality of fluid ejectors in the at least one fluid injection module are provided as orifices fluidly connected to the at least one compressed fluid source. Orifices are particularly easy to manufacture and thus reduce the manufacturing / installation cost of the lift conversion device. Alternatively or additionally, the fluid ejectors or orifices can be placed at different locations with respect to the rotor blades. Thus, the position of the fluid curtain on the suction side can be adjusted and the separation position of the fluid flow around the airfoil can be changed. By providing the orifices in the fluid injection module as attachments to the rotor blades rather than providing them in the rotor blades themselves, particularly in the housing, the structural integrity of the rotor blades is maintained.

[0025] Furthermore, it can be provided that a vortex generator (eddy current generator), ramps, spoilers, and / or flaps are attached to the at least one fluid injection module. This allows for further modification of the lift achieved by the at least one fluid injection module, designed as an add-on. The vortex generator, for example, can increase the lift coefficient of the rotor blades during normal operation in certain situations. However, when operational or environmental conditions require it, the lift coefficient can be effectively reduced by means of a lift-changing device. This approach may seem strange because the vortex generator and lift-changing device achieve opposite effects. However, since the lift-changing device is active, the vortex generator can be used to increase the efficiency of the wind turbine while still allowing for load reduction when needed by activating the lift-changing device. Furthermore, by carefully placing the injection orifice in combination with the vortex generator or other devices, air can be injected at a very localized level close to the individual components (e.g., the fins of the vortex generator). In this way, the vortex generation process at the vortex generator is suppressed. The vortex generator, ramp, spoiler, and / or flap can be individual components reversibly attached to the at least one fluid jet module. Thus, these components can be easily replaced when damaged, and additional components can be easily added to the fluid jet module.

[0026] Similarly, it can be provided that at least one fluid supply line connecting the at least one fluid injection module to the at least one compressed fluid source is at least partially arranged inside the rotor blade, and preferably attached to the web of the rotor blade spars. Furthermore, any other components of the lift conversion device (such as compressed fluid sources or valves) can be arranged within the rotor blade.

[0027] Alternatively, the at least one fluid supply line may be externally attached to the outer surface of the rotor blade and routed to a feed port inside the housing of the rotor blade, through which the at least one fluid supply line is fed into the interior of the rotor blade. The at least one fluid supply line may be routed chordally externally (i.e., on the outer side of the rotor blade) from the fluid injection module to the trailing edge. For example, the feed port may be located chordally between the at least one fluid injection module and the trailing edge or directly at the trailing edge. Alternatively, the at least one fluid supply line may be routed entirely externally to the rotor blade. In this case, the at least one fluid supply line may be routed chordally from the fluid injection module to the trailing edge and then along the trailing edge to the root of the rotor blade.

[0028] Similarly, the rotor blades may include at least one structural reinforcement at the location of the feed hole. This structurally reinforces weak points around the feed hole to prevent failure at those locations. The at least one structural reinforcement may, for example, comprise a laminate of one or more additional layers surrounding the feed hole, relative to the adjacent outer surface of the feed hole.

[0029] It can be provided that the at least one compressed fluid source is a compressed fluid source. A compressed fluid source allows for the efficient generation of compressed fluid and high compression, thereby generating a fluid curtain with high momentum. Specifically, the compressed fluid source can be at least one of a compressor, blower, turbocharger, or piston with a fluid or air reservoir. The fluid can be a gas. Furthermore, the fluid can be, in particular, air, nitrogen, or any other inert gas. The fluid can be dry air or atmospheric air.

[0030] Furthermore, it can be provided that the at least one fluid jet module is at least two fluid jet modules, each of which includes multiple fluid jets. Again, both fluid jet modules are mounted as attachments to the outer surface of the rotor blades. This provides greater flexibility in the installation of the lift-changing device within the rotor blades. For example, multiple fluid jet modules can be mounted to the outer surface of the rotor blades at a distance from each other, providing a greater span along the rotor blades, rather than having fluid jets along the entire length of that span. Thus, despite this, the effect of changing lift can still be achieved with lower manufacturing / installation costs and a lower requirement for pressurized fluid flow rates.

[0031] Here, it can be provided that each of the at least two fluid injection modules is connected to the at least one compressed fluid source by means of a valve and / or each of the at least two fluid injection modules is connected to a single compressed fluid source among the at least one compressed fluid source. By means of the valve, the supply of compressed fluid from the at least one compressed fluid source can be controlled such that some of the at least two fluid injection modules can be activated, supplied with compressed fluid to generate a fluid curtain, while others can be deactivated, i.e., not supplied with compressed fluid, and thus they do not generate a fluid curtain. When there are individual compressed fluid sources (i.e., at least two) connected to fluid injection modules, the individual compressed fluid sources can be controlled by means of their operation (i.e., opening or closing) to activate or deactivate the fluid injection modules fluidly connected to them. Thus, the size and position of the fluid curtain along the span of the rotor blades can be adjusted, thereby allowing for changes in lift according to the current requirements of certain operating or environmental conditions.

[0032] Furthermore, it can be provided here that each of the at least two fluid injection modules is connected to the at least one compressed fluid source via a separate fluid supply line. This further enables the fluid injection module to be activated independently by means of at least one compressed fluid source.

[0033] Furthermore, the lift-changing device may include a control unit connected to the at least one compressed fluid source and / or at least one valve arranged between the at least one fluid injection module and the at least one compressed fluid source, wherein the control unit is configured to change the momentum of the compressed fluid exiting the plurality of fluid injectors by controlling the at least one compressed fluid source and / or the at least one valve. Specifically, the control unit may be configured to adjust the momentum of the compressed fluid exiting the fluid injectors according to the current requirements of certain operational or environmental conditions, for example, by opening and closing the at least one compressed fluid source or changing the pressure of the compressed fluid from the compressed fluid source.

[0034] Here, it can be provided that the control unit is configured to operate the at least one compressed fluid source and / or alternately close and open the at least one valve, such that compressed fluid exits the plurality of fluid injectors as compressed fluid pulses. Operation of the compressed fluid source can cause it to be alternately opened and closed, or the compression of the fluid or the output of the compressed fluid source can be alternately increased and decreased. A compressed fluid pulse is a pulse of compressed fluid exiting the plurality of fluid injectors. In other words, a pulse is a sequence of a significant amount of compressed fluid exiting the plurality of fluid injectors after little or no compressed fluid has exited, and this sequence is repeated. Such an operating method can be particularly advantageous in mitigating asymmetrical loads on the rotor of a wind turbine, such as during operation under yaw inflow conditions, when balancing tilt loads on the main bearings of the wind turbine, and in fault conditions, such as when a blade is stuck due to a faulty pitch system.

[0035] According to a second aspect of the invention, the problem is solved by a method for mounting rotor blades according to a first aspect of the invention, wherein rotor blades are provided and the at least one fluid injection module is mounted as an attachment to the outer surface of the rotor blades on the suction side or pressure side.

[0036] The at least one fluid injection module can be reversibly or irreversibly mounted to the outer surface of the suction or pressure side of the rotor blade. It can be mounted to the outer surface of the rotor blade by means of at least one adhesive, at least one tape, and / or mechanical fasteners. The rotor blade itself can be newly manufactured or already existing, i.e., used. Therefore, used rotor blades can be retrofitted using the at least one fluid injection module and connected to other components of an existing lift conversion device, particularly a compressed fluid source, or used rotor blades can be retrofitted using the entire lift conversion device including the at least one fluid injection module.

[0037] Provided, the rotor blade housing has a recess into which the at least one fluid injection module is fitted. Thus, the new rotor blade can be equipped with the at least one fluid injection module, allowing the at least one fluid injection module to be seamlessly integrated into the rotor blade without any or only a negligible impact on the aerodynamic properties of the rotor blade. Attached Figure Description

[0038] Further advantages, features, and details of the invention will become apparent from the following description, in which reference is made to the accompanying drawings. Figures 1 to 15 The embodiments of the invention will be described in more detail below. Therefore, features from the claims and features mentioned in the specification, either individually or in any combination, may be very important to the invention. In the drawings, the following are schematically shown:

[0039] Figure 1 This is a side perspective view of the rotor blades according to the first embodiment.

[0040] Figure 2 This is a side perspective view of a section of the rotor blade according to the second embodiment.

[0041] Figure 3 It is in operation and the lift conversion device is deactivated. Figure 1 A side view of the rotor blades.

[0042] Figure 4 It is in operation and in which the lift-changing device is activated. Figure 1 A side view of the rotor blades.

[0043] Figure 5 This is a cross-sectional view through a portion of the rotor blade according to the third embodiment.

[0044] Figure 6 This is a side perspective view of a section of another rotor blade.

[0045] Figure 7It is equipped with a fluid jet module according to the first embodiment. Figure 6 A side perspective view of the rotor blades.

[0046] Figure 8 It is equipped with a fluid jet module according to the second embodiment. Figure 6 A side perspective view of the rotor blades.

[0047] Figure 9 It is equipped with a fluid jet module according to the third embodiment. Figure 6 A side perspective view of the rotor blades.

[0048] Figure 10 It is equipped with a fluid jet module according to the fourth embodiment. Figure 6 A side perspective view of the rotor blades.

[0049] Figure 11 This is a side perspective view of another rotor blade equipped with a fluid jet module in a first position according to the first embodiment.

[0050] Figure 12 According to the second embodiment Figure 11 A side perspective view of the rotor blades equipped with the fluid injection module in the first position.

[0051] Figure 13 According to the third embodiment Figure 11 A side perspective view of the rotor blades equipped with the fluid injection module in the first position.

[0052] Figure 14 It is a side perspective view of the rotor blades equipped with the fluid injection module in the second position, and

[0053] Figure 15 This is a side perspective view of the rotor blades equipped with the fluid injection module in the third position. Detailed Implementation

[0054] Figures 1 to 15 Identical objects in the figures are labeled with the same reference numerals. If more than one object of the same type exists in a figure, the objects are numbered in ascending order, with the ascending number of the object separated from its reference numeral by a dot. Specific dimensions of features and parts in the figures are schematic and may be enlarged for ease of reference only.

[0055] Figure 1 A side perspective view of the rotor blade 10 according to a first embodiment is shown. The rotor blade 10 includes a lift conversion device 20.

[0056] The lift conversion device 20 includes a fluid injection module 21. The fluid injection module 21 is mounted as an attachment, in the form of a panel, to the outer surface of the suction side 17 of the rotor blade 10. Mounting can be performed by means of adhesives, tapes, and / or mechanical fasteners. However, none of these are shown here or in the accompanying drawings; only the state in which the fluid injection module 21 is mounted to the outer surface of the housing 11 of the rotor blade 10 is shown.

[0057] like Figure 1 The lift-changing device 20 shown is activated, thus generating a fluid curtain A. A fluid jet module 21 is mounted on the suction side 17 of the rotor blade 10, closer to the leading edge 15 of the rotor blade 10 than to its trailing edge 16. Furthermore, the fluid jet module 21 is provided closer to the tip of the rotor blade 10 than to its root. However, if desired, the fluid jet module 21 can alternatively be placed closer to the trailing edge 16 or the root. Similarly, alternatively, the fluid jet module 21 can be arranged on the pressure side 18 of the rotor blade 10 (see...). Figure 15 The pressure side 18 is positioned opposite the suction side 17 at the rotor blade 10. Figures 11 to 15 This additional exemplary alternative to the positioning of the fluid injection module 21 is shown in the figure and will be discussed later with reference to it.

[0058] In this specific embodiment, the fluid injection module 21 is exposed to the outside of the rotor blades 10, while other components of the lift conversion device 20 (i.e., the fluid supply line 27, the compressed fluid source 22, and the control unit 28) are located inside the rotor blades 10. However, the control unit 28 could alternatively be located, for example, at the hub of the wind turbine. Therefore, the fluid supply line 27, the compressed fluid source 22, and the control unit 28 are depicted in dashed lines. The locations of the compressed fluid source 22 and the control unit 28 are merely exemplary, and these components could also be located inside the wind turbine with the rotor blades 10. Similarly, the compressed fluid source 22 could be located directly at or near the fluid injection module 21. The compressed fluid source 22 is configured to supply compressed fluid to the fluid injection module 21 via the fluid supply line 27. Here, the compressed fluid source 22 is a compressor and the fluid is air. However, other fluids and other types of compressed fluid sources 22 could be used.

[0059] Figure 2A side perspective view of a section of the rotor blade 10 according to a second embodiment is shown. In this second embodiment, the lift conversion device 20 includes two separate fluid injection modules 21.1 and 21.2. However, the number of fluid injection modules 21 may be fewer or more. The fluid injection modules 21.1 and 21.2 are attached as attachments to the outer surface of the suction side 17 of the rotor blade 10 and are closer to the leading edge 15 than to the trailing edge 16. However, the fluid injection modules 21.1 and 21.2 may alternatively be arranged closer to the trailing edge 16 than to the leading edge 15.

[0060] Each of the fluid jetting modules 21.1 and 21.2 includes a plurality of fluid jetters 23. Fluid jetters 23.1, 23.2, and 23.3 of fluid jetting module 21.1 are exemplary labeled. In this case, the fluid jetters 23 are provided as orifices within the fluid jetting modules 21.1 and 21.2. The fluid jetters 23 are linearly aligned to produce a substantially straight fluid curtain A, as... Figure 1 As shown in the image.

[0061] Furthermore, the fluid injection modules 21.1 and 21.2 are arranged a distance apart from each other. However, they can alternatively be arranged next to each other.

[0062] Each of the fluid injection modules 21.1 and 21.2 is fluidly connected to the compressed fluid source 22 via a separate fluid supply line 27.1 and 27.2. Figure 2 (Not shown in the image). Alternatively, each of the fluid injection modules 21.1, 21.2 can be connected to one of the multiple compressed fluid sources 22 (in the image). Figure 2 (Not shown in the image).

[0063] Each of the fluid supply lines 27.1 and 27.2 has a valve 29.1 or 29.2 installed therein. Valves 29.1 and 29.2 are connected to a control unit 28 (in... Figure 2 (Not shown in the image). By controlling valves 29.1 and 29.2, control unit 28 can close or open individual fluid supply lines 27.1 and 27.2 and selectively activate fluid injection modules 21.1 and 21.2. Alternatively, these two valves 29.1 and 29.2 can be three-way valves 29, and fluid supply lines 27.1 and 27.2 can converge at the three-way valve 29. Similarly, when there are more than two fluid injection modules 21.1 and 21.2, there can be more fluid supply lines 27 and more valves 29. The hydraulic or pneumatic circuit of the fluid injection module 21 with compressed fluid source 22 depends on the specific equipment, and there are multiple possible circuits that provide selective activation of individual fluid injection modules 21.1 and 21.2 by means of control unit 28. Figure 2Only exemplary embodiments are shown to explain the principles thereon.

[0064] Fluid supply lines 27.1 and 27.2 are arranged within the interior 12 of the rotor blade 10. They are attached to the spar web 13 of the rotor blade 10. In this embodiment, the spar is an I-beam type with two spar caps 14.1 and 14.2. However, the spar can also be any other type, such as a box spar. Alternatively, the fluid supply lines 27.1 and 27.2 can be attached to the inside of the housing 11 of the rotor blade 10.

[0065] The rotor blades 10 are further provided with a plurality of vortex generators 30.1, 30.2, 30.3, 30.4, 30.5, and 30.6, six of which are schematically shown and labeled. The vortex generators 30 are attached to the fluid jet modules 21.1 and 21.2 of the rotor blades 10 and increase the lift coefficient. The vortex generators 30 can be integrated with the fluid jet modules 21.1 and 21.2 or attached to the fluid jet modules by means of mechanical fasteners, tape, and / or adhesives, allowing them to be easily maintained and / or replaced.

[0066] Figure 3 The diagram shows the device in operation, in which the lift conversion device 20 is deactivated. Figure 1 A side view of the rotor blade 10. Here, the airflow W surrounding the airfoil is not separated by the fluid jet module 21 of the lift conversion device 20. Thus, the airflow W is the attached airflow W surrounding the airfoil.

[0067] Figure 4 The diagram shows the device in operation, in which the lift-changing device 20 is activated. Figure 1 A side view of the rotor blades. The fluid injection module 21 generates a fluid curtain A or an air curtain A and thereby separates the airflow W at the fluid curtain A. After the fluid injection module 21, the airflow W becomes a separated fluid flow and forms a stalled flow. This reduces the lift coefficient of the rotor blades 10 and simultaneously increases the drag coefficient of the rotor blades 10.

[0068] Figure 5 A cross-sectional view is shown through a portion of the rotor blade 10 according to the third embodiment. Figure 2 Unlike the rotor blade 10, the fluid injection module 21 is embedded in the groove 31 of the housing 11 of the rotor blade 10.

[0069] The fluid injection module 21 has a curved external shape on its outer side 25 to correspond to the shape of the housing 11 of the rotor blade 10. The inner side 26 corresponds in shape to the recessed shape of the groove 31 inside the housing 11 of the rotor blade 10 to form a form-fitting fit. The fluid injection module 21 has an elongated body that includes a fluid flow channel 24 that is fluidly connected to the compressed fluid source 22 and the fluid ejector 23.

[0070] Figure 6 A side perspective view of a portion of a rotor blade 10 having its housing 11 is shown.

[0071] Figure 7 A portion of the fluid jet module 21 is shown, which is mounted as an add-on in the form of a panel. Figure 6 The outer surface of the suction side 17 of the housing 11 of the rotor blade 10. In this specific embodiment, the fluid jet module 21 has a plurality of fluid jet modules 21 (here and below) provided as orifices in the fluid jet module 21. Figures 8-10 Only one is marked in the text) and several other vortex generators 30 (only one is marked). The fluid jet module 21, which is shaped into a panel, has a basically flat shape with two large opposing surfaces.

[0072] Figure 8 An alternative fluid injection module 21 is shown, which is installed to Figure 6 The fluid jet module 21 is located on the outer surface of the suction side 17 of the housing 11 of the rotor blade 10. The fluid jet module 21 includes only a plurality of fluid jets 23. Furthermore, the fluid jet module 21 is embedded in a groove 31 inside the housing 11 of the rotor blade 10 and is mounted thereto.

[0073] Figure 9 It shows Figure 7 The rotor blade 10 differs in that the fluid injection module 21 only includes multiple fluid injectors 23. Such a fluid injection module 21 can be installed as an add-on onto the rotor blade 10 without requiring any structural changes to the rotor blade 10.

[0074] Figure 10 It shows Figure 9 An enlarged portion of the rotor blade 10 is shown, which shows the fluid injection module 21 along its entire length and wherein the fluid supply line 27 is externally attached to the housing 11 of the wind turbine 10 and extends in the chordal direction of the rotor blade 10 to the trailing edge 16 of the rotor blade 10.

[0075] Figure 11The rotor blade 10 is shown across its entire span. A rectangular fluid injection module 21 is attached as an accessory to the suction side 17 of the rotor blade 10 and is positioned approximately halfway across the suction side 17. A fluid supply line 27 is laid chordally from the fluid injection module 21 to a position between the fluid injection module 21 and the trailing edge 16 of the rotor blade 10. In this position, the fluid supply line 27 is fed into the interior 12 of the rotor blade 10 through the outer surface or housing 11 of the rotor blade 10. To feed the fluid supply line 27 into the interior 12, a feed hole 32 is provided in the outer surface or housing 11 of the rotor blade 10. Once inside the rotor blade 10, the fluid supply line 27 is laid along the sparsity web 13 of the rotor blade 10, as shown... Figure 2 As shown, it may be arranged along the upper or lower surface or trailing edge surface of the interior 12 of the rotor blade 10. Alternatively, it may be guided along prefabricated channels within the structure of the rotor blade 10.

[0076] Figure 12 An alternative arrangement of the fluid supply line 27 in the rotor blade 10 is shown, wherein the fluid injection module 21 is installed in conjunction with... Figure 11 At the same location as the fluid injection module 21. The fluid supply line 27 is laid in the chord direction from the fluid injection module 21 to the trailing edge 16 and thus along the trailing edge 16 in the direction of the root of the rotor blade 10 to a defined position on the trailing edge 16, where the fluid supply line 27 is again fed through the feed hole 32 and thus through the outer surface of the rotor blade 10 to the interior 12 of the rotor blade 10.

[0077] Figure 13 This illustrates another alternative arrangement of the fluid supply line 27 in the rotor blade 10, wherein the fluid injection module 21 is installed with... Figure 11 At the same location as the fluid injection module 21, the fluid supply line 27 is again laid out in the chord direction from the fluid injection module 21 to the trailing edge 16. Thereafter, the fluid supply line 27 is laid along the trailing edge 16 and outside the rotor blade 10 toward the root of the rotor blade 10.

[0078] Figure 14 The rotor blade 10 is also shown across its entire span. A fluid injection module 21 is attached as an add-on to the suction side 17 of the rotor blade 10 and is located on the outer side of the suction side 17. A fluid supply line 27 extends chordally from the fluid injection module 21 to the trailing edge 16. Thereafter, the fluid supply line 27 extends along the trailing edge 16 toward the root of the rotor blade 10. Alternatively, the fluid supply line 27 can be fed through a feed hole 32 in the housing 11 of the rotor blade 10 to the interior 12 of the rotor blade 10, as shown. Figure 11 and Figure 12 As shown in the image.

[0079] exist Figure 15 In this figure, the fluid injection module 21 is mounted as an attachment to the pressure side 18 of the rotor blade 10. The fluid supply line 27 is not shown in this figure, but can be arranged as previously explained, specifically referring to... Figures 11 to 14 .

Claims

1. A rotor blade (10) for a wind turbine, the rotor blade (10) comprising a lift conversion device (20) having at least one fluid injection module (21) and at least one compressed fluid source (22), wherein the at least one fluid injection module (21) comprises a plurality of fluid injectors (23) fluidly connected to the at least one compressed fluid source (22), wherein the at least one fluid injection module (21) is mounted as an attachment to the outer surface of the suction side (17) or pressure side (18) of the rotor blade (10).

2. The rotor blade (10) according to claim 1, wherein the at least one fluid injection module (21) is configured to generate a fluid curtain (A) of separated airflow (W) on the suction side (17) or the pressure side (18) of the rotor blade (10) when the at least one compressed fluid source (22) supplies compressed fluid to the at least one fluid injection module (21).

3. The rotor blade (10) according to claim 1 or 2, wherein the at least one fluid injection module (21) is designed as a panel.

4. The rotor blade (10) according to claim 1 or 2, wherein the at least one fluid injection module (21) has a curved profile.

5. The rotor blade (10) according to claim 1 or 2, wherein the at least one fluid injection module (21) is mounted to the outer surface of the rotor blade (10) by means of at least one adhesive, at least one tape and / or mechanical fastener.

6. The rotor blade (10) according to claim 1 or 2, wherein the at least one fluid injection module (21) is reversibly mounted on the outer surface of the rotor blade (10).

7. The rotor blade (10) according to claim 1 or 2, wherein the at least one fluid injection module (21) is embedded in a groove (31) of the housing (11) of the rotor blade (10).

8. The rotor blade (10) according to claim 1 or 2, wherein the at least one fluid injection module (21) includes a fluid flow channel (24) in fluid communication with the plurality of fluid injectors (23).

9. The rotor blade (10) according to claim 1 or 2, wherein the plurality of fluid injectors (23) in the at least one fluid injection module (21) are provided to be fluidly connected to the orifice of the at least one compressed fluid source (22).

10. The rotor blade (10) according to claim 1 or 2, wherein the vortex generator (30), the ramp, the spoiler and / or the flap are attached to the at least one fluid jet module (21).

11. The rotor blade (10) according to claim 1 or 2, wherein at least one fluid supply line (27) fluidly connecting the at least one fluid injection module (21) to the at least one compressed fluid source (22) is arranged at least partially in the interior (12) of the rotor blade (10).

12. The rotor blade (10) according to claim 1 or 2, wherein at least one fluid supply line (27) fluidly connecting the at least one fluid injection module (21) to the at least one compressed fluid source (22) is arranged at least partially in the interior (12) of the rotor blade (10) and is attached to the spar web (13) of the rotor blade (10).

13. The rotor blade (10) according to claim 11, wherein the at least one fluid supply line (27) is externally attached to the outer surface of the rotor blade (10) and disposed in a feed hole (32) inside the housing (11) of the rotor blade (10), through which the at least one fluid supply line (27) is fed into the interior (12) of the rotor blade (10).

14. The rotor blade (10) according to claim 13, wherein the rotor blade (10) includes at least one structural reinforcement at the location of the feed hole (32).

15. A method for mounting a rotor blade (10) according to any one of the preceding claims, wherein the rotor blade (10) is provided and the at least one fluid injection module (21) is mounted as an attachment to the outer surface of the suction side (17) and / or the pressure side (18) of the rotor blade (10).

16. The method according to claim 15, wherein the housing (11) of the provided rotor blade (10) has a groove (31) into which the at least one fluid injection module (21) is fitted.

Images