Noise reduction device, blade and blade forming method

Abstract

The present invention discloses a noise reduction device, a blade and a blade forming method. The noise reduction device is used for the blade, and the noise reduction device comprises: a body, including a mounting portion, and the body can be connected to the blade through the mounting portion; a sawtooth unit, connected to the body, the edge of the sawtooth unit has a sawtooth structure, and the sawtooth unit is set at a preset angle α with the body, and the preset angle α satisfies: 1°≤α≤5°. The noise reduction device, blade and blade forming method provided by the present invention can reduce the aerodynamic noise generated by the blade during operation and improve the stability of the blade operation.

Description

Technical Field

[0001] The present invention relates to the technical field of wind power, and in particular to a noise reduction device, a blade and a blade forming method. Background Art

[0002] With the continuous development of wind power technology, wind turbines tend to be larger and closer to residential areas. However, wind turbines will generate aerodynamic noise during operation, which will seriously affect the lives of surrounding residents and cause environmental pollution. In addition, the noise will cause fatigue and damage to the structure of wind turbines.

[0003] The main practice at present is to install noise reducers on the blades to reduce the aerodynamic noise generated by the blades. However, the wind speed and wind force to which the wind turbine is subjected often change during operation. The current noise reducers cannot effectively reduce the aerodynamic noise generated by the wind turbine due to unreasonable structural settings.

[0004] Therefore, there is an urgent need to provide a new noise reduction device, blade and blade forming method. Summary of the invention

[0005] The embodiments of the present invention provide a noise reduction device, a blade, and a blade forming method, which are intended to reduce aerodynamic noise generated during blade operation and improve the stability of blade operation.

[0006] On the one hand, an embodiment of the present invention provides a noise reduction device for a blade, the noise reduction device comprising: a main body, comprising a mounting portion, the main body can be connected to the blade through the mounting portion; a serration unit, connected to the main body, the edge of the serration unit has a serration structure, the serration unit is set at a preset angle α to the main body, and the preset angle α satisfies: 1°≤α≤5°.

[0007] According to one aspect of the embodiment of the present invention, the preset angle α is 3°.

[0008] According to one aspect of the embodiments of the present invention, the edge of the sawtooth unit has a plurality of sawtooth structures, and the plurality of sawtooth structures are arranged in a contracted manner in a direction away from the main body; optionally, the sawtooth structure is a triangle.

[0009] According to one aspect of an embodiment of the present invention, the sawtooth unit includes a base and two intersecting reference edges, and the extension lines of the two reference edges and the base together form a virtual triangle; the sawtooth unit includes a plurality of noise reduction parts connected to each other, and the plurality of noise reduction parts are arranged in the virtual triangle, and the noise reduction parts are polygonal structures, and the plurality of noise reduction parts are arranged in sequence along a direction away from the main body, and the edges of the plurality of noise reduction parts are connected to each other to form a plurality of sawtooth structures; optionally, two adjacent noise reduction parts are arranged to be inclined to each other; optionally, the number of the plurality of noise reduction parts is greater than or equal to three.

[0010] According to one aspect of an embodiment of the present invention, the noise reduction portion includes a connecting portion and a serrated portion that are interconnected, the serrated portion includes a serrated structure, the connecting portion and the serrated portion are inclined to each other, and the inclination angle between the connecting portion and the serrated portion is 1° to 3°.

[0011] According to one aspect of an embodiment of the present invention, the noise reduction device can be installed on a blade, and along the height direction of the sawtooth unit, the blade has a first chord length corresponding to the sawtooth unit, and the sawtooth unit includes a bottom edge and a vertex facing away from the bottom edge, and the distance between the bottom edge and the vertex is the height of the sawtooth unit; wherein the height of the sawtooth unit is 15% to 20% times the corresponding first chord length.

[0012] According to one aspect of the embodiment of the present invention, the length of the bottom side of the sawtooth unit is the width of the sawtooth unit, and the height of the sawtooth unit is 3 times the width of the sawtooth unit.

[0013] According to one aspect of the embodiments of the present invention, the body and the sawtooth unit are integrally formed.

[0014] On the other hand, an embodiment of the present invention provides a blade, comprising: a shell, including a trailing edge; a noise reduction device, such as the noise reduction device described above, the noise reduction device being arranged on the trailing edge of the shell.

[0015] On the other hand, an embodiment of the present invention provides a blade forming method, comprising: a shell; and connecting a noise reduction device to the shell to form a blade, wherein the noise reduction device is the above-mentioned noise reduction device.

[0016] The noise reduction device, blade and blade forming method provided by the embodiment of the present invention, the noise reduction device includes a body and a sawtooth unit, the body can be stably connected to the blade through a mounting portion, the sawtooth unit is connected to the body, and the edge of the sawtooth unit has a sawtooth structure, so that the turbulent flow flowing through the surface of the blade forms a plurality of reverse vortex pairs and cancels each other out. When the noise reduction device is applied to the blade, the sawtooth structure can change the turbulent flow on the surface of the blade, break up the vortex pairs on the surface of the blade, reduce the energy of the vortex pairs, so as to reduce the pulsating pressure generated when the vortex pairs and the blade surface act, thereby reducing the noise generated by the blade during operation. Furthermore, the body of the noise reduction device and the sawtooth unit are arranged at a preset angle. On the premise that the body is stably connected to the trailing edge of the blade, the sawtooth unit can better destroy the vortex generated on the surface of the blade during the rotation of the blade, thereby improving the noise reduction effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The following is a brief introduction to the drawings required for use in the embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0018] Figure 1is a structural schematic diagram of a wind turbine generator set according to an embodiment of the present invention;

[0019] Figure 2 is an overall schematic diagram of a blade according to an embodiment of the present invention;

[0020] Figure 3 yes Figure 2 The enlarged view of point A in the middle;

[0021] Figure 4 yes Figure 2 Cross-sectional view in the BB direction;

[0022] Figure 5 is a schematic structural diagram of a noise reduction device according to an embodiment of the present invention;

[0023] Figure 6 is a side view of a noise reduction device according to an embodiment of the present invention;

[0024] Figure 7 is a structural schematic diagram of a sawtooth unit according to an embodiment of the present invention;

[0025] Figure 8 is a structural schematic diagram of a sawtooth unit according to another embodiment of the present invention

[0026] Fig. 9 is a structural schematic diagram of a sawtooth unit according to another embodiment of the present invention;

[0027] Fig.10 is a side view of a sawtooth unit according to an embodiment of the present invention;

[0028] Fig.11 yes Fig. 9 Sectional view at CC;

[0029] Fig.12 is an experimental result diagram of a test model installed with different noise reduction devices, wherein the ratio formed by the height of the sawtooth unit and the width of the sawtooth unit in multiple noise reduction devices is the same, and the angles between the body and the sawtooth unit are different;

[0030] Fig.13 is an experimental result diagram of a test model installed with different noise reduction devices, wherein the angle between the body and the sawtooth unit is the same, and the ratio of the height of the sawtooth unit to the width of the sawtooth unit in multiple noise reduction devices is different;

[0031] Fig.14 1 is a graph showing experimental results of installing a noise reduction device according to one embodiment of the present invention and a noise reduction device according to another embodiment of the present invention on a test model;

[0032] Fig.15 The figure is a schematic flow chart of a blade forming method according to an embodiment of the present invention.

[0033] Marking Description:

[0034] in:

[0035] 1-impeller; 100-blade; 200-hub; X-axial direction; Y-chord direction;

[0036] 10-housing; 11-windward shell; 12-leeward shell; 13-leading edge area; 14-trailing edge area; 15-blade root; 16-blade tip; 17-hollow space;

[0037] 20 - abdominal plate;

[0038] 30-noise reduction device; 31-body; 311-mounting part; 312-first surface; 32-serrated unit; 321-second surface; 322-serrated structure; 323-first noise reduction part; 3231-connecting part; 3232-serrated part; H-height; W-width; 33-bottom edge; 34-reference edge; 324-second noise reduction part; 325-third noise reduction part;

[0039] 2-Generator;

[0040] 3- Cabin;

[0041] 4-Tower. DETAILED DESCRIPTION

[0042] The features and exemplary embodiments of various aspects of the present invention will be described in detail below. In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only configured to explain the present invention and are used to illustrate the principles of the present invention, and are not configured to limit the present invention. In addition, the structural components in the drawings are not necessarily drawn to scale. For example, the sizes of some structural components or areas in the drawings may be enlarged for other structural components or areas to help understand the embodiments of the present invention.

[0043] The directional words appearing in the following description are all directions shown in the figures, and do not limit the specific structure of the embodiments of the present invention. In the description of the present invention, it should be noted that, unless otherwise specified, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0044] In addition, the terms "include", "comprises", "has" or any other variations thereof are intended to cover non-exclusive inclusion, so that a structure or assembly comprising a series of elements includes not only those elements, but also other mechanisms that are not explicitly listed or inherent in the structure or assembly. In the absence of further restrictions, the elements defined by the sentence "includes..." do not exclude the presence of other identical elements in the article or device comprising the elements. For those skilled in the art, the present invention can be implemented without the need for some of these specific details. The following description of the embodiments is merely to provide a better understanding of the present invention by illustrating examples of the present invention.

[0045] The features and exemplary embodiments of various aspects of the present invention will be described in detail below.In addition, the features, structures, or characteristics described below may be combined in any suitable manner in one or more embodiments.

[0046] In order to better understand the present invention, Figures 1 to 15 The noise reduction device 30, the blade 100 and the blade forming method according to the embodiment of the present invention are described in detail.

[0047] See also Figure 1 , Figure 1 The structural schematic diagram of a wind turbine generator set in the prior art is shown. The wind turbine generator set mainly includes a tower 4, a nacelle 3, a generator 2 and an impeller 1. The nacelle 3 is arranged at the top of the tower 4. The generator 2 is arranged in the nacelle 3 and can be located inside the nacelle 3 or outside the nacelle 3. The impeller 1 includes a hub 200 and two or more blades 100 respectively connected to the hub 200. The blades 100 drive the hub 200 to rotate under the action of wind load, thereby realizing the power generation of the generator 2.

[0048] In order to make the wind turbine generator set operate better, the embodiment of the present invention provides a new blade 100, please refer to Figure 2 as well as Figure 4 , Figure 2 shows an overall schematic diagram of a blade according to an embodiment of the present invention, Figure 3 Show Figure 2 The enlarged view of point A in the middle. Figure 4 Shows Figure 2 Cross-sectional view along the BB direction.

[0049] The blade 100 provided in the embodiment of the present invention comprises a shell 10, a web 20 and a noise reduction device 30. The shell 10 has an axial direction X and a chord direction Y. The shell 10 comprises a windward shell 11 and a leeward shell 12 arranged opposite to each other. The windward shell 11 and the leeward shell 12 are buckled to form a hollow space 17. The shell 10 has a leading edge area 13 and a trailing edge area 14 in the chord direction Y, and has a blade root 15 and a blade tip 16 in the axial direction X. The web 20 is arranged in the hollow space 17, and the web 20 is connected to the windward shell 11 and the leeward shell 12. The web 20 can support the shell 10 of the blade 100 to enhance the strength of the blade 100. The blade 100 is provided with a noise reduction device 30 on the side away from the hollow space 17, which is used to reduce the noise generated when the blade 100 is running.

[0050] In some embodiments, when the airflow blows toward the blade 100, the airflow interacts with the blade 100 to form turbulence flowing along the surface of the blade 100. Since the blade 100 is in operation, the turbulence on the surface of the blade 100 will hit the blade 100 and generate greater aerodynamic noise. By providing a noise reduction device 30 on the surface of the blade 100, the aerodynamic noise generated by the blade 100 in the operation can be effectively reduced, and the stability of the operation of the blade 100 can be improved.

[0051] In some embodiments, the blade 100 includes a trailing edge, which is disposed near the tip 16 of the blade 100. When the airflow blows toward the blade 100, the airflow interacts with the blade 100 to form turbulence along the surface of the blade 100. The turbulence scatters sound at the trailing edge to form noise, and the greater the intensity of the turbulence, the greater the noise. In order to effectively reduce the aerodynamic noise of the blade 100 during operation, the noise reduction device 30 is disposed on the trailing edge to effectively reduce the noise on the trailing edge surface, while being able to improve the stability of the blade 100.

[0052] In order to better reduce the aerodynamic noise generated during the operation of the blade 100, the embodiment of the present invention provides a novel noise reduction device 30. Please refer to Figures 5 to 11 , Figure 5 A schematic diagram showing the structure of a noise reduction device according to an embodiment of the present invention is shown. Figure 6 A side view showing a noise reduction device according to an embodiment of the present invention, Figure 7 A schematic diagram showing the structure of a sawtooth unit according to an embodiment of the present invention is shown. Figure 8 A schematic diagram showing the structure of a sawtooth unit according to another embodiment of the present invention is shown. Fig. 9 A schematic diagram showing the structure of a sawtooth unit according to another embodiment of the present invention is shown. Fig.10 A side view showing a sawtooth unit according to an embodiment of the present invention, Fig.11 Show Fig. 9 Cross-sectional view at CC.

[0053] The embodiment of the present invention provides a noise reduction device 30 for a blade 100. The noise reduction device 30 includes a body 31 and a sawtooth unit 32. The body 31 includes a mounting portion 311, and the body 31 can be connected to the blade 100 through the mounting portion 311. The sawtooth unit 32 is connected to the body 31, and the edge of the sawtooth unit 32 has a sawtooth structure 322. The sawtooth unit 32 is set at a preset angle α with the body 31, and the preset angle α satisfies: 1°≤α≤5°.

[0054] The noise reduction device 30 provided in the embodiment of the present invention includes a body 31 and a sawtooth unit 32. The body 31 can be stably connected to the blade 100 through the mounting portion 311. The sawtooth unit 32 is connected to the body 31. The edge of the sawtooth unit 32 has a sawtooth structure 322, so that the turbulent flow flowing through the surface of the blade 100 forms a plurality of reverse vortex pairs and cancels each other out. When the noise reduction device 30 is applied to the blade 100, the sawtooth unit 32 can change the turbulent flow on the surface of the blade 100, break up the vortex pairs on the surface of the blade 100, reduce the energy of the vortex pairs, so as to reduce the pulsating pressure generated when the vortex pairs and the surface of the blade 100 act, thereby reducing the noise generated by the blade 100 during operation.

[0055] Furthermore, the main body 31 of the noise reduction device 30 and the serration unit 32 are arranged at a preset angle α. Under the premise that the main body 31 and the blade 100 are stably connected, the serration unit 32 can better destroy the turbulence generated on the surface of the blade 100 during the rotation of the blade 100, thereby improving the noise reduction effect.

[0056] In some optional embodiments, along the direction of the thickness of the body 31 itself, the body 31 includes a first surface 312 opposite to the mounting portion 311, the sawtooth unit 32 includes a second surface 321, and the preset angle α between the sawtooth unit 32 and the body 31 is the angle between the first surface 312 and the second surface 321. In some embodiments, the preset angle α is 3°. Experiments show that setting the preset angle to 3° can effectively improve the noise reduction effect of the blade 100. By reasonably setting the distance between the first surface 312 and the second surface 321, the sawtooth unit 32 can better break up the vortex on the surface of the blade 100, so as to effectively reduce the aerodynamic noise generated during the operation of the blade 100. Optionally, in order to enhance the stability of the connection between the blade 100 and the noise reduction device 30, the shape of the mounting portion 311 matches the shape of the surface of the blade 100, so as to increase the connection area between the mounting portion 311 and the blade 100.

[0057] See also Figure 7 In some embodiments, the sawtooth unit 32 is triangular in shape as a whole, and the noise can be effectively reduced by reasonably setting the structure of the sawtooth unit 32 and the preset angle between the sawtooth unit 32 and the body 31.

[0058] In some optional implementations, the noise reduction device 30 includes a plurality of sawtooth units 32 to break up the turbulence on the surface of the blade 100. Figures 8 to 11 , at least part of the edge of the sawtooth unit 32 has a plurality of sawtooth structures 322, and the plurality of sawtooth structures 322 are arranged in a direction away from the body 31. By arranging the plurality of sawtooth structures 322 in a direction away from the body 31, the overall profile of the sawtooth unit 32 is similar to a triangle or a trapezoid, so as to better break up the turbulence on the surface of the blade 100 to form a smaller vortex. At the same time, by setting a plurality of sawtooth structures 322 on the edge of the sawtooth unit 32, each sawtooth structure 322 can further break up the smaller vortex, so that the energy of the vortex after being broken up by the plurality of sawtooth structures 322 is significantly reduced, so as to better reduce the aerodynamic noise generated by the vortex hitting the surface of the blade 100.

[0059] Optionally, the sawtooth structure 322 is triangular. The triangular sawtooth structure 322 has a stress concentration portion, so that the sawtooth structure 322 can quickly and effectively break up the turbulence, so that the distance between the vortex pairs formed by the turbulence is closer, and the mutual offset effect is strong, which is conducive to improving the noise reduction effect, thereby reducing the aerodynamic noise generated by the blade 100 during operation. Of course, it can be understood that the sawtooth structure 322 can also be a trapezoidal structure, a broken line structure, and a circular arc structure or a combination thereof.

[0060] In some optional embodiments, the sawtooth unit 32 includes a base 33 and two intersecting reference edges 34, and the extension lines of the two reference edges 34 and the base 33 together form a virtual triangle. The sawtooth unit 32 includes a plurality of noise reduction parts 323 connected to each other, and the plurality of noise reduction parts 323 are arranged in the virtual triangle. The noise reduction parts 323 are polygonal structures, and the plurality of noise reduction parts 323 are arranged in sequence along a direction away from the main body 31, and the edges of the plurality of noise reduction parts 323 are connected to each other to form a plurality of sawtooth structures 322.

[0061] Optionally, the widths of the multiple noise reduction parts 323 decrease in a direction away from the body 31. The multiple noise reduction parts include a first noise reduction part 323, which is arranged close to the body 31, and the side of the first noise reduction part 323 close to the body 31 is the bottom side 33 of the sawtooth unit 32, and the two sides of the first noise reduction part 323 intersecting with the bottom side 33 coincide with the reference side 34 of the sawtooth unit 32. At this time, the extension lines of the two reference sides 34 and the bottom side 33 together form a virtual triangle.

[0062] In a specific implementation, a triangular sawtooth unit 32 may be first manufactured, and then the edge of the triangular sawtooth unit 32 may be further processed so that a plurality of sawtooth structures 322 are formed on the edge of the sawtooth unit 32. At this time, the plurality of sawtooth structures 322 are all arranged in the sawtooth unit 32. When the blade 100 is in operation, since the sawtooth unit 32 is triangular, the sawtooth unit 32 may initially break up the turbulence with a large amount of energy, and then further break up the initially broken up vortex pairs through the pair of sawtooth structures 322 on the edge of the sawtooth unit 32, so as to effectively reduce the aerodynamic noise generated on the surface of the blade 100.

[0063] Optionally, the number of the multiple noise reduction units is greater than or equal to three. For details, please refer to Fig.10 The multiple noise reduction parts include a first noise reduction part 323, a second noise reduction part 324 and a third noise reduction part 325. The multiple noise reduction parts can better weaken the energy of turbulence on the surface of the blade 100. At the same time, by reasonably setting the number of the multiple noise reduction parts, the number of serrated structures 322 formed on the edges of the multiple noise reduction parts is large, so that more reverse vortex pairs are formed after the turbulence is broken up. The energy of the turbulence will be reduced due to the increase in the number of vortex pairs, which is beneficial to improving the noise reduction effect.

[0064] In order to more effectively break up the turbulence on the surface of the blade 100 in all directions and reduce the aerodynamic noise generated on the surface of the blade 100, two adjacent noise reduction parts are arranged to be inclined with respect to each other. In a specific embodiment, the first noise reduction part 323, the second noise reduction part 324 and the third noise reduction part 325 can be arranged to be inclined with respect to each other. The structures of the first noise reduction part 323, the second noise reduction part 324 and the third noise reduction part 325 are similar, and the embodiment of the present invention takes the first noise reduction part 323 as an example for description.

[0065] In some optional embodiments, the first noise reduction portion includes a connecting portion 3231 and a sawtooth portion 3232 connected to each other, and the sawtooth portion 3232 forms a sawtooth structure 322, such as Fig.11 As shown, the connection portion 3231 and the sawtooth portion 3232 are arranged to be inclined with respect to each other, and the inclination angle between the connection portion 3231 and the sawtooth portion 3232 is 1° to 3°. Since the wind speed and wind force to which the blade 100 is subjected often change during operation, by reasonably setting the structure of the noise reduction portion, the sawtooth structure 322 can break up turbulence in multiple directions to improve the noise reduction effect.

[0066] Furthermore, the first noise reduction portion 323 includes two sawtooth portions 3232 and a connecting portion 3231 disposed between the two sawtooth portions 3232 and connecting the two sawtooth portions 3232, wherein the shapes of the two sawtooth portions 3232 on the same noise reduction portion may be the same or different. Of course, the shapes of the sawtooth portions 3232 between different noise reduction portions may also be set according to user needs. For example, the sawtooth portion 3232 of the first noise reduction portion 323 may form a triangular sawtooth structure, and the sawtooth portion 3232 of the second noise reduction portion 324 may form a rectangular sawtooth structure.

[0067] In some optional embodiments, the noise reduction device 30 can be mounted on the blade 100, and along the height direction of the sawtooth unit 32, the blade 100 has a first chord length corresponding to the sawtooth unit 32, and the sawtooth unit 32 includes a bottom edge 33 and a vertex away from the bottom edge 33, and the distance between the bottom edge 33 and the vertex is the height H of the sawtooth unit 32, wherein the height H of the sawtooth unit 32 is 15% to 20% times the corresponding first chord length. Optionally, the length of the bottom edge 33 of the sawtooth unit 32 is the width W of the sawtooth unit 32, and the height H of the sawtooth unit 32 is 3 times the width W of the sawtooth unit 32. By reasonably setting the relationship between the height H of the sawtooth unit 32 and the corresponding first chord length, in the axial direction X of the blade 100, as the first chord length of the blade 100 changes, the height of the sawtooth unit 32 will change along with the first chord length. Furthermore, since the height H and the width W of the sawtooth unit 32 have a corresponding relationship, when the first chord length of the blade 100 changes, the width W of the sawtooth unit 32 also changes along with the first chord length, so that the sawtooth unit 31 can more effectively reduce the noise generated by the blade 100.

[0068] In order to improve the stability of the noise reduction device 30 and to better perform the noise reduction function, the body 31 of the noise reduction device 30 and the sawtooth unit 32 are integrally formed, and the noise reduction device 30 is made of resin mixed with chopped glass fibers.

[0069] In order to accurately and comprehensively test the noise characteristics of the noise reduction device 30 and the blade 100, in some embodiments, the noise characteristics of the blade 100 provided with the noise reduction device 30 are tested by using a microphone array method and a wind tunnel experiment. Among them, the microphone array method for testing noise and the wind tunnel experiment are well understood by those skilled in the art, and will not be described in detail here, nor should they be used as a limitation to the present invention.

[0070] When conducting a noise characteristic test, a test model is first made according to the shape parameters of the tip portion 16 of the blade 100. For example, the test model can be made in proportion to the trailing edge size of the actual blade 100. The test model is then placed on a test device for experimentation. It is understood that the test device can rotate the test model to simulate the rotation and yaw of the blade 100 during operation. In an embodiment of the present invention, a microphone array surrounding a test section of 55° to 115° is selected to experiment on the noise reduction effect of the noise reduction device. For example, in a noise characteristic test experiment, the microphone array is respectively placed at 50°, 60°, 70°, 80°, 90° and 100° positions of the test model to collect the noise generated by the test model during operation.

[0071] Please also read Figure 12 to Figure 14 , Fig.12 The graph shows the experimental results of the test model being installed with different noise reduction devices, wherein the ratio between the height of the sawtooth unit and the width of the sawtooth unit in the multiple noise reduction devices is the same, and the angles between the body and the sawtooth unit are different. Fig.13 The experimental result diagram of the test model installed with different noise reduction devices is shown, wherein the angle between the body and the sawtooth unit is the same, and the ratio between the height of the sawtooth unit and the width of the sawtooth unit in multiple noise reduction devices is different. Fig.14 The graphs show the experimental results of the test model respectively installing the noise reduction device of one embodiment of the present invention and the noise reduction device of another embodiment of the present invention.

[0072] It should be noted that the attached Fig.12 The baseline in FIG. 1 is the noise test result of the test model during operation when the test model is not equipped with the noise reduction device 30 of the embodiment of the present invention. Fig.12 , L1, L2 and L3 are noise results measured by using a microphone array when different noise reduction devices 30 are installed on the test model.

[0073] Specifically, in L1, the angle between the body 31 of the noise reduction device 30 installed on the test model and the sawtooth unit 32 is 1 degree, and the ratio between the height H of the sawtooth unit 32 and the width W of the sawtooth unit 32 is 1, that is, H / W=1. In L2, the angle between the body 31 of the noise reduction device 30 installed on the test model and the sawtooth unit 32 is 3 degrees, and the ratio between the height H of the sawtooth unit 32 and the width W of the sawtooth unit 32 is 1, that is, H / W=1. In L3, the angle between the body 31 of the noise reduction device 30 installed on the test model and the sawtooth unit 32 is 5 degrees, and the ratio between the height H of the sawtooth unit 32 and the width W of the sawtooth unit 32 is 1, that is, H / W=1.

[0074] From the attached Fig.12It can be seen that the noise result represented by L1 is about 1dBA lower than the baseline, the noise result represented by L2 is about 3dBA lower than the baseline, and the noise result represented by L3 is about 2dBA lower than the baseline. Compared with the baseline, the noise results represented by L1, L2 and L3 are all smaller than the noise reduction effect represented by the baseline. Therefore, when the test model is equipped with the noise reduction device 30 of the embodiment of the present invention, the noise of the test model equipped with the noise reduction device 30 is significantly reduced as measured by the microphone array method. The experiment proves that the noise reduction device 30 of the embodiment of the present invention can significantly reduce the noise generated by the test model during operation. By installing the noise reduction device 30 of the embodiment of the present invention on the test model, the noise can be reduced by about 1dBA to 3dBA.

[0075] Please see attached Fig.13 , where L4, L5 and L6 are the noise results measured by the microphone array when different noise reduction devices 30 are installed on the test model. Specifically, in L4, the ratio between the height H of the sawtooth unit 32 and the width W of the sawtooth unit 32 is 5, that is, H / W=5, and the angle between the body 31 of the noise reduction device 30 installed on the test model and the sawtooth unit 32 is 3 degrees. In L5, the ratio between the height H of the sawtooth unit 32 and the width W of the sawtooth unit 32 is 3, that is, H / W=3, and the angle between the body 31 of the noise reduction device 30 installed on the test model and the sawtooth unit 32 is 3 degrees. In L6, the ratio between the height H of the sawtooth unit 32 and the width W of the sawtooth unit 32 is 1, that is, H / W=1, and the angle between the body 31 of the noise reduction device 30 installed on the test model and the sawtooth unit 32 is 3 degrees.

[0076] from Fig.13 It can be seen that the noise result represented by L4 is about 3dBA lower than the baseline, the noise result represented by L5 is about 3.5dBA lower than the baseline, and the noise result represented by L6 is about 2dBA lower than the baseline. Compared with the baseline, the noise results represented by L4, L5 and L6 are all less than the noise reduction effect represented by the baseline. Therefore, when the test model is installed with the noise reduction device 30 of the embodiment of the present invention, the noise of the test model equipped with the noise reduction device 30 is significantly reduced as measured by the microphone array method. The experiment proves that the noise reduction device 30 of the embodiment of the present invention can significantly reduce the noise generated by the test model during operation. By installing the noise reduction device 30 of the embodiment of the present invention on the test model, the noise can be reduced by about 2dBA to 3.5dBA.

[0077] Please see attached Fig.14 , wherein L9 is an experimental result diagram of a test model installed with a noise reduction device 30 according to an embodiment of the present invention. At this time, the structure of the sawtooth unit 32 of the noise reduction device 30 can be as follows Figure 7As shown, the edge of the sawtooth unit 32 has a sawtooth structure 322. L7 and L8 are respectively experimental result diagrams of the test model installed with the noise reduction device 30 of another embodiment of the present invention. At this time, the structure of the sawtooth unit 32 of the noise reduction device 30 can be as follows: Figure 8 or attached Fig. 9 As shown, the edge of the sawtooth unit 32 has a plurality of sawtooth structures 322. Specifically, L7 is a test model installed with an attached Fig. 9 The experimental results of the noise reduction device 30 shown in FIG. L8 are test models equipped with the attached Figure 8 The experimental results of the noise reduction device 30 are shown.

[0078] Depend on Fig.14 It can be seen that the noise result represented by L7 is about 2.5dBA lower than the baseline, the noise result represented by L8 is about 5dBA lower than the baseline, and the noise result represented by L9 is about 3.5dBA lower than the baseline. By setting the noise reduction device 30 of the embodiment of the present invention on the test model, the noise level generated by the test model during operation can be significantly reduced. Fig.14 It can be seen from the figure that by installing the noise reduction device 30 of the embodiment of the present invention on the test model, the noise can be reduced by about 2.5 dBA to 5 dBA relative to the baseline.

[0079] Experiments have shown that the noise reduction device 30 provided in the embodiment of the present invention can significantly reduce the noise generated by the test model during operation. Therefore, when the noise reduction device 30 provided in the embodiment of the present invention is applied to the blade 100, it can effectively improve the noise reduction effect of the blade 100. It is understandable that the user can design the ratio between the height H and the width W of the sawtooth unit 32 and the angle value between the body 31 and the sawtooth unit 32 according to actual needs.

[0080] In summary, the noise reduction device 30 provided by the embodiment of the present invention has a body 31 that can be stably connected to the blade 100 through the mounting portion 311, and the sawtooth unit 32 is connected to the body 31. The edge of the sawtooth unit 32 has a sawtooth structure 322, so that the turbulent flow flowing through the surface of the blade 100 forms a plurality of reverse vortex pairs and cancels each other out. When the noise reduction device 30 is applied to the blade 100, the sawtooth structure 322 can change the turbulent flow on the surface of the blade 100, break up the vortex pairs on the surface of the blade 100, reduce the energy of the vortex pairs, and reduce the pulsating pressure generated when the vortex pairs and the surface of the blade 100 act, thereby reducing the noise generated by the blade 100 during operation. Further, the body 31 of the noise reduction device 30 and the sawtooth unit 32 are arranged at a preset angle. Under the premise that the body 31 is stably connected to the root 15 of the blade 100, the sawtooth unit 32 can better destroy the vortex generated on the surface of the blade 100 during the rotation of the blade 100, thereby improving the noise reduction effect.

[0081] The present invention also provides a blade forming method, see Fig.15 , Fig.15 A flow chart showing a blade forming method according to an embodiment of the present invention is shown.

[0082] A blade forming method according to an embodiment of the present invention comprises the following steps:

[0083] S110, housing provided.

[0084] S120, a noise reduction device is connected to the housing to form a blade.

[0085] The noise reduction device is any one of the above embodiments.

[0086] The blade forming method provided in an embodiment of the present invention includes connecting a noise reduction device 30 to a shell 10 to form a blade 100. The noise reduction device 30 is a noise reduction device 30 provided by any of the above embodiments, so that during the operation of the formed blade 100, the noise reduction device 30 can form a plurality of directional vortex pairs of turbulence flowing through the surface of the blade 100 and offset each other, thereby effectively controlling the noise in the propagation path and improving the noise reduction effect of the noise reduction device 30.

[0087] Before step S110, a step of forming a shell may be included. In some embodiments, the step of forming the shell may include:

[0088] Step 1: Provide a windward shell and a leeward shell.

[0089] Step 2: bonding the web to one of the windward shell or the leeward shell.

[0090] Step 3, closing the mold of the windward shell and the leeward shell to form an outer shell.

[0091] In the step of forming the shell, a bonding adhesive such as epoxy resin can be applied to the web 20 using a glue coating tool with the inner surface of the windward shell 11 facing upward, and the web 20 can be bonded to the web 20 bonding area of ​​the windward shell 11. It is understandable that the web 20 can also be bonded to the leeward shell 12 first, and the present invention is not limited to this.

[0092] In step S120, a glue coating tool may be used to apply epoxy resin or the like on the surface of the housing 10, and the body 31 of the noise reduction device 30 may be bonded to the surface of the housing 10. The blade 100 includes a blade root 15 and a blade tip 16. The noise reduction device 30 may be bonded to the blade tip 16 of the blade 100, or the noise reduction device 30 may be installed along the entire axial direction of the blade 100. In some embodiments, the noise reduction device 30 may be installed on the windward shell 11, or may be installed on the leeward shell 12 at the same time, so as to reduce the aerodynamic noise of the blade 100 in all directions.

[0093] In summary, the noise reduction device 30, the blade 100 and the blade forming method provided in the embodiment of the present invention, the noise reduction device 30 can form the turbulence flowing through the surface of the blade 100 into multiple directional vortex pairs and offset each other, thereby minimizing the aerodynamic noise generated by the blade 100 during operation, improving the quality of the blade 100 and the stability of the operation of the blade 100, and therefore, it is easy to promote and use.

[0094] It should be understood that the terms "first", "second", etc., and other relational terms are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. It should be understood that the terms used in this way are interchangeable under appropriate circumstances, so that the embodiments of the invention described herein, for example, can be operated or arranged in a sequence other than those described herein or otherwise.

[0095] The present invention may be implemented in other specific forms without departing from its spirit and essential characteristics. Therefore, the current embodiments are considered to be illustrative rather than restrictive in all aspects, the scope of the present invention is defined by the appended claims rather than the above description, and all changes that fall within the meaning and equivalents of the claims are included in the scope of the present invention. In addition, different technical features appearing in different embodiments may be combined to achieve beneficial effects. Those skilled in the art should be able to understand and implement other variations of the disclosed embodiments based on a study of the drawings, the specification and the claims.

Claims

1. A noise reduction device for a blade, characterized in that: The noise reduction device comprises: A body, comprising a mounting portion, through which the body can be connected to the blade; A sawtooth unit connected to the body, the edge of the sawtooth unit having a sawtooth structure, the sawtooth unit and the body are arranged at a preset angle α, and the preset angle α satisfies: 1°≤α≤5°; The edge of the sawtooth unit has a plurality of sawtooth structures, and the plurality of sawtooth structures are arranged in a contracted manner in a direction away from the body; the sawtooth structure is a triangle; the sawtooth unit includes a base and two intersecting reference sides, and the extension lines of the two reference sides and the base together form a virtual triangle; the sawtooth unit includes a plurality of noise reduction parts connected to each other, and the plurality of noise reduction parts are arranged in the virtual triangle, and the noise reduction parts are polygonal structures, and the plurality of noise reduction parts are arranged in sequence in a direction away from the body, and the edges of the plurality of noise reduction parts are connected to each other to form the plurality of sawtooth structures; two adjacent noise reduction parts are arranged to be inclined with respect to each other; the number of the plurality of noise reduction parts is greater than or equal to three; The noise reduction portion includes a connecting portion and a sawtooth portion that are connected to each other, the sawtooth portion forms the sawtooth structure, the connecting portion and the sawtooth portion are arranged to be inclined relative to each other, and the inclination angle between the connecting portion and the sawtooth portion is 1° to 3°.

2. The noise reduction device according to claim 1, characterized in that: The preset angle α is 3°.

3. The noise reduction device according to claim 1, characterized in that: The noise reduction device can be mounted on the blade, and along the height direction of the sawtooth unit, the blade has a first chord length corresponding to the sawtooth unit, the sawtooth unit includes a bottom edge and a vertex facing away from the bottom edge, and the distance between the bottom edge and the vertex is the height of the sawtooth unit; Wherein, the height of the sawtooth unit is 15% to 20% times the corresponding first chord length.

4. The noise reduction device according to claim 3, characterized in that: The length of the bottom side of the sawtooth unit is the width of the sawtooth unit, and the height of the sawtooth unit is 3 times the width of the sawtooth unit.

5. The noise reduction device according to claim 1, characterized in that: The body and the sawtooth unit are integrally formed.

6. A blade, characterized in that: include: the outer shell, including the trailing edge; A noise reduction device according to any one of claims 1 to 5, wherein the noise reduction device is arranged on the rear edge of the shell.

7. A blade forming method, characterized in that: include: Provide a housing; A noise reduction device is connected to the housing to form a blade, Wherein, the noise reduction device is the noise reduction device according to any one of claims 1 to 5.

Images