Fan blade, axial flow fan and air conditioner

Abstract

The utility model relates to the technical field of fans, in particular to a fan blade, an axial flow fan and an air conditioner. The fan blade has a first direction, a second direction and a third direction which are intersected pairwise, and the fan blade comprises a pressure surface, a suction surface, a blade main body and a plurality of sawteeth; the face, in the third direction, of the fan blade is a suction face, and the other face, in the third direction, of the fan blade is a pressure face. The sawteeth are arranged in the first direction, and the ends, in the positive direction of the second direction, of the sawteeth are connected with the ends, in the negative direction of the second direction, of the blade body. A noise reduction channel is formed in the position, close to the sawteeth, of the blade body, one end of the noise reduction channel is located on the pressure face, and the other end of the noise reduction channel is located on the suction face. The noise reduction channel can enlarge and disperse the pressure concentration area and reduce the pressure pulsation of the pressure concentration area, so that the noise problem caused by the pressure pulsation is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of fans, in particular to a fan blade, an axial flow fan and an air conditioner. Background Art

[0002] A fan is a machine that relies on input mechanical energy to increase gas pressure and discharge gas. It is a driven fluid machine. Fan is a customary abbreviation for gas compression and gas delivery machinery. The fans usually mentioned include ventilators, blowers, wind turbines, axial flow fans, etc. Fans are widely used in ventilation, dust removal and cooling of factories, mines, tunnels, cooling towers, vehicles, ships and buildings, ventilation and air induction of boilers and industrial furnaces; cooling and ventilation in air conditioning equipment and household appliances; drying and selection of grains, wind tunnel wind sources and inflation and propulsion of hovercraft, etc. With the gradual increase in the performance requirements of fans, the size and speed of fans increase, and the noise problem is relatively large.

[0003] At present, setting asymmetric sawtooth leading edge on the fan blade is an effective noise reduction solution. Its noise reduction mechanism is to change the pressure pulsation of the fan blade leading edge, thereby reducing the inflow noise generated by the contact between the fan blade leading edge and turbulence. However, the trough of the asymmetric sawtooth leading edge will produce a strong noise source due to the pressure concentration problem. Therefore, the fan still has the problem of high noise. Utility Model Content

[0004] In view of this, the utility model proposes a fan blade, an axial flow fan and an air conditioner, aiming to partially or completely solve the technical problem that the existing fans still have relatively high noise.

[0005] In order to achieve the above object, the technical solution of the utility model is implemented as follows:

[0006] In the first aspect, an embodiment of the utility model provides a fan blade having a first direction, a second direction and a third direction that intersect each other, the fan blade comprising a pressure surface, a suction surface, a blade body and a plurality of serrations; one side of the fan blade in the third direction is a suction surface, and the other side of the third direction is a pressure surface; the plurality of serrations are arranged along the first direction, and the ends of the serrations in the positive direction of the second direction are connected to the ends of the blade body in the negative direction of the second direction; a noise reduction channel is provided on the blade body near the serrations, one end of the noise reduction channel is located on the pressure surface, and the other end of the noise reduction channel is located on the suction surface.

[0007] Optionally, the noise reduction channel includes a plurality of first through holes, a plurality of second through holes, and a connecting channel; one end of the first through hole is arranged on the suction surface, one end of the second through hole is arranged on the pressure surface, the first through hole is relative to and the second through hole is close to the saw tooth; the connecting channel is located in the blade body and is arranged along the second direction, one end of the connecting channel close to the saw tooth is connected to the other end of all the first through holes, and the other end of the connecting channel away from the saw tooth is connected to the other end of all the second through holes.

[0008] Optionally, the suction surface of the fan blade is provided with a first noise reduction zone, and the first noise reduction zone has a rectangular structure. One end of the first noise reduction zone is close to the side of the sawtooth in the first direction, and the other end of the first noise reduction zone extends toward the trailing edge of the fan blade. The first through hole is provided on the first noise reduction zone.

[0009] Optionally, in the second direction, the length of the fan blade is C, and the length of the first noise reduction zone is L2, satisfying 0.095C≤L2≤0.105C.

[0010] Optionally, the pressure surface of the fan blade is provided with a second noise reduction zone, and the second noise reduction zone has a rectangular structure; in the second direction, one end of the second noise reduction zone is close to the first noise reduction zone, and the other end of the second noise reduction zone extends toward the trailing edge end of the fan blade, and the second through hole is provided on the second noise reduction zone.

[0011] Optionally, in the second direction, the length of the fan blade is C, and the length of the second noise reduction zone is L3, satisfying 0.045C≤L3≤0.055C.

[0012] Optionally, in the first direction, the tooth tip of the sawtooth deviates from the center line of the sawtooth; and the plurality of noise reduction channels are close to the side edges of the sawtooth in the first direction.

[0013] Optionally, a cross section is made parallel to the plane where the first direction and the second direction are located, and the sawtooth is a right-angled triangle-like structure; a right-angled side of the right-angled triangle-like structure is connected to the end of the blade body in the negative direction of the second direction, and the other right-angled side of the right-angled triangle-like structure is perpendicular to the end of the blade body in the negative direction of the second direction, and the hypotenuse of the right-angled triangle-like structure is a curved surface convex away from the two right-angled sides.

[0014] Optionally, in the second direction, the length of the fan blade is C, the length of the sawtooth is L1, and 0.0095C≤L1≤0.0105C.

[0015] Optionally, in the second direction, the length of the fan blade is C; in the first direction, the width of the sawtooth is W, 0.0065C≤W≤0.0075C.

[0016] Optionally, a third through hole is provided on the outer periphery of the sawtooth, one end of the third through hole is located on the pressure surface, and the other end of the third through hole is located on the suction surface.

[0017] Optionally, the diameter of the first through hole is φ1, satisfying 0.0075C≤φ1≤0.0085C; and / or, the diameter of the second through hole is φ2, satisfying 0.0075C≤φ2≤0.0085C; and / or, the diameter of the third through hole is φ3, satisfying 0.0075C≤φ3≤0.0085C; wherein the length of the fan blade in the second direction is C.

[0018] Optionally, multiple first through holes are arranged along the first direction and the second direction, and the spacing between two adjacent first through holes in the first direction is L4, and / or the spacing between two adjacent first through holes in the second direction is L4, satisfying 0.0015C≤L4≤0.0025C; and / or, multiple second through holes are arranged along the first direction and the second direction, and the spacing between two adjacent second through holes in the first direction is L5, and / or the spacing between two adjacent second through holes in the second direction is L5, satisfying 0.0015C≤L5≤0.0025C; multiple third through holes are provided, and the multiple third through holes are provided along the periphery of the sawtooth, and the spacing between two adjacent third through holes is L6, satisfying 0.0015C≤L6≤0.0025C.

[0019] Optionally, the fan blade is an owl wing 50% cross-section airfoil.

[0020] Optionally, in the second direction, the connection between the end of the sawtooth in the positive direction of the second direction and the end of the blade body in the negative direction of the second direction is located at N, satisfying 0.08C≤N≤0.12C, wherein the length of the fan blade in the second direction is C.

[0021] Optionally, in the third direction, the thickness of the connection between the end of the sawtooth in the positive direction of the second direction and the end of the blade body in the negative direction of the second direction is H, satisfying 0.08C≤H≤0.12C, wherein the length of the fan blade in the second direction is C.

[0022] Optionally, in the second direction, the fitting formula of the suction surface of the blade body is: y=a1x+a2x2+a3x3+a4x4+a5x5+a6x6+c1; wherein, a1=-0.704±0.145, a2=0.203±0.145, a3=-0.019±0.00571, a4=9.50971E-4±3.47592E-4, a5=-2.33032E-5±1.00263E-5, a6=2.25073E-7±1.10087E-7, c1=0.98819±0.12741, x is the horizontal coordinate and y is the vertical coordinate.

[0023] In a second aspect, an embodiment of the utility model further provides an axial flow fan, which includes a fan body and the above-mentioned fan blades, wherein the fan blades are arranged in the fan body.

[0024] In a third aspect, an embodiment of the utility model further provides an air conditioner, which includes the above-mentioned axial flow fan.

[0025] The utility model discloses a fan blade, wherein a plurality of saw teeth are provided at the leading edge end of the fan blade. When the fan blade rotates, the plurality of saw teeth redistribute the pressure pulsation of the leading edge of the fan blade, thereby reducing the leading edge pressure of the fan blade and effectively reducing the inflow noise generated by the leading edge of the fan blade contacting with turbulence. However, the saw teeth concentrate part of the pressure pulsation to the trough of the saw teeth, and the trough of the saw teeth is the connection between the side of the saw teeth in the first direction X and the end of the blade body in the negative direction of the second direction Y. A noise reduction channel is provided near the saw teeth on the blade body, one end of the noise reduction channel is located on the pressure surface, and the other end of the noise reduction channel is located on the suction surface. The noise reduction channel is located in the pressure concentration area of ​​the blade body near the saw teeth. The noise reduction channel can expand and disperse the pressure concentration area, reduce the pressure pulsation in the pressure concentration area, and thus reduce the noise problem caused by the pressure pulsation. Therefore, the fan blade can effectively reduce the fan noise.

[0026] The above description is only an overview of the technical solution of the utility model. In order to more clearly understand the technical means of the utility model, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for describing the embodiments are briefly introduced below.

[0028] Figure 1 This is a schematic diagram of the front view structure of the fan blade according to an embodiment of the utility model;

[0029] Figure 2 for Figure 1 A structural diagram of the enlarged view of part A;

[0030] Figure 3 for Figure 1 A schematic diagram of the structure of the enlarged view of part B;

[0031] Figure 4 It is a schematic diagram of the side view structure of the fan blade according to an embodiment of the utility model, the abscissa shows the length of the fan blade in the second direction (10 cells), the ordinate shows the thickness of the fan blade in the third direction (less than two cells), and the abscissa and the ordinate show the shape of the fan blade;

[0032] Figure 5 for Figure 1 The structural schematic diagram of the C-C cross-section in the middle, the abscissa shows the length of the fan blade in the second direction, (10 cells);

[0033] Figure 6 It is a schematic diagram of a fitting curve of the suction surface of the leading edge of a fan blade according to an embodiment of the present utility model.

[0034] Description of reference numerals:

[0035] 10-blade body; 11-suction surface; 12-pressure surface; 13-noise reduction channel; 14-first through hole; 15-second through hole; 16-connecting channel; 17-first noise reduction area; 18-second noise reduction area; 191-wave crest; 192-wave trough;

[0036] 20 - sawtooth; 21 - third through hole; 22 - bevel edge; 23 - tooth tip;

[0037] X-first direction; Y-second direction; Z-third direction. DETAILED DESCRIPTION

[0038] The exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can also be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0039] Reference Figure 1, which shows a schematic diagram of the front view structure of a fan blade provided by an embodiment of the utility model. The utility model embodiment discloses a fan blade, which has a first direction X, a second direction Y and a third direction Z that intersect each other, wherein the first direction X is the extension direction of the leading edge end of the fan blade, the second direction Y is the direction from the leading edge end of the fan blade to the trailing edge end of the fan blade, and the third direction Z is perpendicular to both the first direction X and the second direction Y. Specifically, in the embodiment of the present application, the first direction X, the second direction Y and the third direction Z are perpendicular to each other.

[0040] Reference Figure 1 and Figure 5 As shown, Figure 5 A structural schematic diagram is shown in which a fan blade is provided with a pressure surface 12 and a suction surface 11, and the fan blade includes the pressure surface 12, the suction surface 11, a blade body 10 and a plurality of saw teeth 20; one side of the fan blade in the third direction Z is the suction surface 11, and the other side in the third direction Z is the pressure surface 12; the plurality of saw teeth 20 are arranged along a first direction X, and the ends of the saw teeth 20 in the positive direction of the second direction Y are connected to the ends of the blade body 10 in the negative direction of the second direction Y; a noise reduction channel 13 is provided near the saw teeth 20 on the blade body 10, one end of the noise reduction channel 13 is located on the pressure surface 12, and the other end of the noise reduction channel 13 is located on the suction surface 11.

[0041] Specifically, the fan blades are an important component of the fan. The trailing edge ends of multiple fan blades are used to connect to the impeller. The impeller rotates under the drive of the drive motor, and the impeller drives multiple fan blades to rotate at the same time to convert the fan driving force into airflow energy, thereby realizing the fan's blowing, ventilation, air exchange and other functions.

[0042] Reference Figure 5 As shown, the end of the fan blade in the positive direction of the second direction Y is the trailing edge end of the fan blade, and the end of the fan blade in the negative direction of the second direction Y is the leading edge end of the fan blade. Figure 1 As shown, the lower end of the fan blade is the leading edge end, and the upper end of the fan blade is the trailing edge end. The leading edge end of the fan blade is provided with a plurality of saw teeth 20. When the fan blade is in use, the leading edge of the fan blade will generate pressure pulsation. By changing the pressure pulsation of the leading edge of the fan blade, the inflow noise generated by the contact between the leading edge of the fan blade and the turbulent flow can be reduced. The saw teeth 20 are used to change the pressure pulsation of the leading edge of the fan blade. The trailing edge end of the fan blade is used to connect with the impeller; the connection between the trailing edge end of the fan blade and the impeller includes two situations, one is that the trailing edge end of the fan blade is directly connected to the impeller, and the other is that the trailing edge end of the fan blade is connected to the impeller through a connecting piece. The embodiment of the present application does not make specific restrictions on this, and the specific structure of the trailing edge end of the fan blade is set according to the use requirements.

[0043] In this embodiment, the fan blade also includes a pressure surface 12 and a suction surface 11. Figure 5 As shown, one side of the fan blade in the third direction Z is a suction surface 11, and the other side in the third direction Z is a pressure surface 12. During the rotation of the fan blade, the suction surface 11 contacts the turbulent flow, and the suction surface 11 is the main force-bearing surface.

[0044] Reference Figure 1 As shown, a plurality of saw teeth 20 are arranged in a row vertically along the first direction X, and the end of the saw teeth 20 in the positive direction of the second direction Y is connected to the end of the blade body 10 in the negative direction of the second direction Y, and the connection between the end of the saw teeth 20 in the positive direction of the second direction Y and the end of the blade body 10 in the negative direction of the second direction Y is a smooth transition. The saw teeth 20 are provided with a tooth tip 23 at the end in the negative direction of the second direction Y. In the embodiment of the present application, when the fan blades rotate, the saw teeth 20 can cut the gas, thereby changing the pressure pulsation at the leading edge of the fan blades, thereby reducing the inflow noise generated by the leading edge of the fan blades contacting the turbulent flow.

[0045] The fan blade of the embodiment of the present application is provided with a plurality of saw teeth 20 at the leading edge of the fan blade. When the fan blade rotates, the plurality of saw teeth 20 redistribute the pressure pulsation at the leading edge of the fan blade, reduce the leading edge pressure of the fan blade, and effectively reduce the inflow noise generated by the leading edge of the fan blade contacting the turbulent flow. However, the saw teeth 20 concentrate part of the pressure pulsation at the trough of the saw teeth 20. The trough of the saw teeth 20 is the connection between the side of the saw teeth 20 in the first direction X and the end of the blade body 10 in the negative direction of the second direction Y. Figure 5 , which shows a schematic structural diagram of the crest 191 and trough 192 of the sawtooth 20 in the fan blade. A noise reduction channel 13 is provided near the sawtooth 20 on the blade body 10, one end of the noise reduction channel 13 is located on the pressure surface 12, and the other end of the noise reduction channel 13 is located on the suction surface 11. The noise reduction channel 13 is located in the pressure concentration area of ​​the blade body 10 near the sawtooth 20. The noise reduction channel 13 can expand and disperse the pressure concentration area, reduce the pressure pulsation in the pressure concentration area, and thus reduce the noise problem caused by the pressure pulsation. Therefore, the fan blade can effectively reduce the fan noise.

[0046] Optional, see Figure 5 As shown, the noise reduction channel 13 includes a plurality of first through holes 14, a plurality of second through holes 15, and a connecting channel 16; one end of the first through hole 14 is arranged on the suction surface 11, one end of the second through hole 15 is arranged on the pressure surface 12, the first through hole 14 is relative to the second through hole 15 and close to the saw tooth 20; the connecting channel 16 is located in the blade body 10 and is arranged along the second direction Y, one end of the connecting channel 16 close to the saw tooth 20 is connected to the other end of all the first through holes 14, and the other end of the connecting channel 16 away from the saw tooth 20 is connected to the other end of all the second through holes 15.

[0047] The noise reduction channel 13 includes a plurality of first through holes 14 , a plurality of second through holes 15 and a connecting channel 16 . The connecting channel 16 connects all the first through holes 14 and all the second through holes 15 . The noise reduction channel 13 forms a porous sound absorbing structure.

[0048] Further, see Figure 5 As shown, the suction surface 11 of the fan blade is provided with a first through hole 14, which extends along the third direction from the suction surface 11 into the blade body 10 and communicates with the communication channel 16. The pressure surface 12 of the fan blade is provided with a second through hole 15, which extends along the third direction from the pressure surface 12 into the blade body 10 and communicates with the communication channel 16.

[0049] In the fan blade of the embodiment of the present application, when the fan blade rotates, the multiple saw teeth 20 can reduce the leading edge pressure of the fan blade, and effectively reduce the inflow noise generated by the leading edge of the fan blade contacting the turbulent flow. However, the saw teeth 20 concentrate part of the pressure pulsation to the trough of the saw teeth 20, and the trough will generate a strong noise source due to the pressure concentration problem. The connecting channel 16 connects all the first through holes 14 and all the second through holes 15, so that the pressure surface 12 and the suction surface 11 of the fan blade are connected. The first through hole 14 is close to the saw teeth 20 relative to the second through hole 15, and one end of the first through hole 14 is located on the suction surface 11. Part of the turbulent flow enters through the first through hole 14 and directly acts on the connecting channel 16. The connecting channel 16 generates a new plane in the blade body 10, and makes part of the pressure concentrated in the new plane to reduce the pressure pulsation on the surface of the fan blade, thereby reducing the additional high-frequency noise generated by the pressure pulsation. Although turbulence will generate additional noise sources inside the blade body 10, this noise source is affected by the position and structure and cannot affect the overall noise intensity of the fan blade. Moreover, the connecting channel 16 generates a new plane inside the blade body 10, which will cause the pressure surface 12 and the suction surface 11 of the fan blade to continue to form a pressure difference, reducing the impact of the porous sound absorption structure on the aerodynamic performance of the fan blade. Therefore, the porous sound absorption structure formed by the multiple first through holes 14, the multiple second through holes 15 and the connecting channel 16 can be used for sound absorption, and the pressure concentration problem is optimized to expand and disperse the pressure concentration area, thereby achieving the effect of noise reduction.

[0050] Optional, see Figure 5As shown, the communication channel 16 is located in the middle of the blade body 10 in the third direction Z, and the communication channel 16 is arranged along the second direction Y. At this time, the communication channel 16 generates a new plane at the center of the blade body 10 in the third direction, and concentrates part of the pressure at the center of the blade body 10 in the third direction, so as to reduce the leading edge pressure pulsation of the fan blade, thereby reducing the additional high-frequency noise generated by the pressure pulsation. Moreover, a new plane is generated at the center of the blade body 10 in the third direction, and the new plane has a certain distance from the pressure surface 12 and the suction surface 11, so as to avoid affecting the overall noise intensity of the fan blade.

[0051] Optionally, the suction surface 11 of the fan blade is provided with a first noise reduction area 17, see Figure 3 , which shows a schematic diagram of the position of the first noise reduction area 17 in the blade body 10. The first noise reduction area 17 is in a rectangular structure, one end of the first noise reduction area 17 is close to the side of the sawtooth 20 in the first direction X, and the other end of the first noise reduction area 17 extends to the trailing edge of the fan blade, and the first noise reduction area 17 is provided with a first through hole 14.

[0052] In the first direction X, the two opposite sides of the sawtooth 20 are both side edges, and the connection between the side edge of the sawtooth 20 in the first direction X and the end of the blade body 10 in the negative direction of the second direction Y is the trough of the sawtooth 20. The first noise reduction area 17 is a rectangular structure, and in the second direction, one end of the first noise reduction area 17 corresponds to the side edge of the sawtooth 20 and is close to the trough of the sawtooth 20, and the other end of the first noise reduction area 17 extends toward the trailing edge end of the fan blade.

[0053] Optionally, the first noise reduction area 17 is provided with a plurality of first through holes 14. In the embodiment of the present application, the number of the first through holes 14 provided on the first noise reduction area 17 is not specifically limited, and the noise reduction requirements of the fan blades can be met. Figure 2 As shown, when the first noise reduction area 17 is provided corresponding to two adjacent saw teeth 20, the first noise reduction area 17 is provided with 33 first through holes 14. Figure 2 As shown, when the first noise reduction area 17 is located at both ends of the blade body 10 in the first direction, the first noise reduction area 17 is arranged corresponding to one side of a sawtooth 20, and 11 first through holes 14 are arranged on the first noise reduction area 17. The first noise reduction area 17 can also be provided with 10 first through holes 14, 20 first through holes 14, etc.

[0054] Optional, see Figure 1 and Figure 3 As shown, in the second direction Y, the length of the fan blade is C, and the length of the first noise reduction area 17 is L2, satisfying 0.095C≤L2≤0.105C. In the embodiment of the present application, when the length of the first noise reduction area 17 is within the above range, the multiple first through holes 14 on the first noise reduction area 17 can achieve a better noise reduction effect.

[0055] Specifically, the length L2 of the first noise reduction area 17 is selected according to the use requirements. For example, the length L2 of the first noise reduction area 17 is 0.095C, L2 is 0.097C, L2 is 0.099C, L2 is 0.1C, L2 is 0.101C, L2 is 0.102C, L2 is 0.103C, L2 is 0.105C, etc.

[0056] Optional, see Figure 1 and Figure 3 As shown, the pressure surface 12 of the fan blade is provided with a second noise reduction zone 18, and the second noise reduction zone 18 is a rectangular structure; in the second direction Y, one end of the second noise reduction zone 18 is close to the first noise reduction zone 17, and the other end of the second noise reduction zone 18 extends toward the trailing edge of the fan blade, and the second noise reduction zone 18 is provided with a second through hole 15.

[0057] The first noise reduction area 17 and the second noise reduction area 18 are both rectangular structures. In the second direction Y, one end of the first noise reduction area 17 is close to the trough of the sawtooth 20, the other end of the first noise reduction area 17 is close to one end of the second noise reduction area 18, and the other end of the second noise reduction area 18 extends to the trailing edge of the fan blade. Figure 3 As shown, the side of the first noise reduction area 17 parallel to the second direction Y and the side of the second noise reduction area 18 parallel to the second direction Y are located on the same straight line. In the first direction X, the width of the first noise reduction area 17 is the same as the width of the second noise reduction area 18.

[0058] Optionally, the second noise reduction area 18 is provided with a plurality of second through holes 15. In the embodiment of the present application, the number of the second through holes 15 provided in the second noise reduction area 18 is not specifically limited, and the noise reduction requirements of the fan blades can be met. Figure 2 As shown, when the first noise reduction zone 17 corresponding to the second noise reduction zone 18 is set corresponding to two adjacent saw teeth 20, the second noise reduction zone 18 is provided with 18 second through holes 15. For another example, when the first noise reduction zone 17 corresponding to the second noise reduction zone 18 is set corresponding to one side of a saw tooth 20, that is, when the second noise reduction zone 18 is located at both ends of the blade body 10 in the first direction, the second noise reduction zone 18 is provided with 6 second through holes 15. The second noise reduction zone 18 can also be provided with 10 second through holes 15, 20 second through holes 15, etc.

[0059] Optionally, in the second direction Y, the number of the first through holes 14 on the corresponding first noise reduction area 17 and the number of the second through holes 15 on the corresponding second noise reduction area 18 may be the same or different, and can be set according to the use requirements. Figure 2 As shown, in the corresponding first noise reduction area 17 and the second noise reduction area 18 , the number of the first through holes 14 is different from the number of the second through holes 15 , and the number of the first through holes 14 is greater than the number of the second through holes 15 .

[0060] Optionally, in the second direction Y, the length of the fan blade is C, and the length of the second noise reduction area 18 is L3, satisfying 0.045C≤L3≤0.055C. In the embodiment of the present application, when the length of the second noise reduction area 18 is within the above range, the plurality of second through holes 15 on the second noise reduction area 18 can achieve a better noise reduction effect.

[0061] Specifically, the length L3 of the second noise reduction area 18 is selected according to the use requirements. For example, the length L3 of the second noise reduction area 18 is 0.045C, L3 is 0.046C, L3 is 0.047C, L3 is 0.048C, L3 is 0.05C, L3 is 0.051C, L3 is 0.053C, and L3 is 0.055C.

[0062] Optional, see Figure 2 As shown, in the first direction X, the tooth tip 23 of the sawtooth 20 deviates from the center line of the sawtooth 20; and the plurality of noise reduction channels 13 are close to the side edge of the sawtooth 20 in the first direction X.

[0063] In the embodiment of the present application, in the first direction X, the tooth tip 23 of the sawtooth 20 is arranged away from the center line of the sawtooth 20, so the sawtooth 20 has an asymmetric sawtooth leading edge. Figure 2 As shown, in the first direction X, the tooth tip 23 of the sawtooth 20 is biased toward the positive direction of the first direction X relative to the center line of the sawtooth 20. The center line of the sawtooth 20 is parallel to the second direction Y and is located in the middle of the sawtooth 20 in the first direction X.

[0064] When the fan blade of the embodiment of the present application is in use, the sawtooth 20 cuts the gas, and the sawtooth 20 can reduce the inflow noise generated by the leading edge of the fan blade contacting the turbulent flow, but due to the noise reduction mechanism of the asymmetric sawtooth leading edge, the pressure pulsation generated by the leading edge of the fan blade is mainly concentrated at the trough of the sawtooth 20. The noise reduction channel 13 is close to the trough of the sawtooth 20, and the pressure pulsation is dispersed again, so as to further reduce the noise.

[0065] In the embodiment of the present application, the embodiment of the present application does not specifically limit the asymmetric sawtooth leading edge structure of the sawtooth 20. For example, in a cross section made parallel to the plane where the first direction X and the second direction Y are located, the sawtooth 20 is a triangular structure, one side of the triangular structure is connected to the end of the blade body 10 in the negative direction of the second direction Y, and the lengths of the other two straight sides of the triangular structure are not equal. For example, the sawtooth 20 is a quasi-triangular structure, one side of the quasi-triangular structure is connected to the end of the blade body 10 in the negative direction of the second direction Y, and the other two sides of the quasi-triangular structure are both curved surfaces.

[0066] Optionally, in a specific embodiment, refer to Figure 2As shown, a cross section is made along a plane parallel to the first direction X and the second direction Y, and the sawtooth 20 is a right-angled triangle structure; a right-angled side of the right-angled triangle structure is connected to the end of the blade body 10 in the negative direction of the second direction Y, and the other right-angled side of the right-angled triangle structure is perpendicular to the end of the blade body 10 in the negative direction of the second direction Y, and the hypotenuse 22 of the right-angled triangle structure is a curved surface convex away from the two right-angled sides.

[0067] Specifically, the two right-angled sides of the above-mentioned quasi-right-angled triangle structure are both straight line segments, and the hypotenuse 22 of the quasi-right-angled triangle structure is a curved surface convex in a direction away from the two right-angled sides.

[0068] Optional, see Figure 3 As shown, in the second direction Y, the length of the fan blade is C, the length of the sawtooth 20 is L1, 0.0095C≤L1≤0.0105C. In the embodiment of the present application, when the length L1 of the sawtooth 20 is within the above range, the sawtooth 20 can disperse the pressure, thereby achieving a better noise reduction effect.

[0069] Specifically, the length L1 of the sawtooth 20 is set according to the use requirements, and the embodiment of the present application does not specifically limit this. For example, L1 is 0.0095C, L1 is 0.0096C, L1 is 0.0097C, L1 is 0.0099C, L1 is 0.01C, L1 is 0.0101C, L1 is 0.0103C, and L1 is 0.00.0105C.

[0070] Optional, see Figure 3 As shown, in the second direction Y, the length of the fan blade is C; in the first direction X, the width of the sawtooth 20 is W, 0.0065C≤W≤0.0075C. When the width W of the sawtooth 20 of the embodiment of the present application is within the above range, the sawtooth 20 can disperse the pressure, thereby achieving a better noise reduction effect.

[0071] Specifically, the width W of the sawtooth 20 is set according to the use requirements, and the embodiment of the present application does not specifically limit this. For example, W is 0.0065C, W is 0.0066C, W is 0.0068C, W is 0.0069C, W is 0.007C, W is 0.0071C, W is 0.0073C, and W is 0.0075C.

[0072] Optional, see Figure 5 As shown, a third through hole 21 is provided on the outer periphery of the sawtooth 20 , one end of the third through hole 21 is located at the pressure surface 12 , and the other end of the third through hole 21 is located at the suction surface 11 .

[0073] In the embodiment of the present application, the third through hole 21 is a noise reduction hole arranged on the sawtooth 20. The third through hole 21 is used to disperse the pressure in the peripheral area of ​​the sawtooth 20 to reduce the pressure pulsation in the peripheral area of ​​the sawtooth 20 and reduce the noise source.

[0074] Optionally, the diameter of the first through hole 14 is φ1, satisfying 0.0075C≤φ1≤0.0085C; and / or, the diameter of the second through hole 15 is φ2, satisfying 0.0075C≤φ2≤0.0085C; and / or, the diameter of the third through hole 21 is φ3, satisfying 0.0075C≤φ3≤0.0085C; wherein the length of the fan blade in the second direction Y is C.

[0075] At this time, the fan blade has the following specific situations: the first situation is that the diameter of the first through hole 14 is φ1, which satisfies 0.0075C≤φ1≤0.0085C. The second situation is that the diameter of the second through hole 15 is φ2, which satisfies 0.0075C≤φ2≤0.0085C. The third situation is that the diameter of the third through hole 21 is φ3, which satisfies 0.0075C≤φ3≤0.0085C. And a combination of two structures in the above three situations, and a combination of three structures in the above three situations.

[0076] When the diameter φ1 of the first through hole 14 in the embodiment of the present application is within the above range, the first through hole 14 can achieve a better noise reduction effect.

[0077] Specifically, the diameter φ1 of the first through hole 14 is set according to the use requirements, and the embodiment of the present application does not specifically limit this. For example, the diameter φ1 of the first through hole 14 is 0.0075C, φ1 is 0.077C, φ1 is 0.079C, φ1 is 0.08C, φ1 is 0.081C, φ1 is 0.083C, φ1 is 0.084C, and φ1 is 0.0085C.

[0078] When the diameter φ2 of the second through hole 15 in the embodiment of the present application is within the above range, the second through hole 15 can achieve a better noise reduction effect.

[0079] Specifically, the diameter φ2 of the second through hole 15 is set according to the use requirements, and the embodiment of the present application does not specifically limit this. For example, the diameter φ2 of the second through hole 15 is 0.0075C, φ2 is 0.077C, φ2 is 0.079C, φ2 is 0.08C, φ2 is 0.081C, φ2 is 0.083C, φ2 is 0.084C, and φ2 is 0.0085C.

[0080] When the diameter φ3 of the third through hole 21 in the embodiment of the present application is within the above range, the third through hole 21 can achieve a better noise reduction effect.

[0081] Specifically, the diameter φ3 of the third through hole 21 is set according to the use requirements, and the embodiment of the present application does not specifically limit this. For example, the diameter of the third through hole 21 is φ3 0.0075C, φ3 0.077C, φ3 0.079C, φ3 0.08C, φ3 0.081C, φ3 0.083C, φ3 0.084C, and φ3 0.0085C.

[0082] Optional, see Figure 2 As shown, a plurality of first through holes 14 are provided, and the plurality of first through holes 14 are arranged along the first direction X and the second direction Y, and the spacing between two adjacent first through holes 14 in the first direction X is L4, and / or, the spacing between two adjacent first through holes 14 in the second direction Y is L4, satisfying 0.0015C≤L4≤0.0025C. And / or, a plurality of second through holes 15 are provided, and the plurality of second through holes 15 are arranged along the first direction X and the second direction Y, and the spacing between two adjacent second through holes 15 in the first direction X is L5, and / or, the spacing between two adjacent second through holes 15 in the second direction Y is L5, satisfying 0.0015C≤L5≤0.0025C. A plurality of third through holes 21 are provided, and the plurality of third through holes 21 are arranged along the periphery of the sawtooth 20, and the spacing between two adjacent third through holes 21 is L6, satisfying 0.0015C≤L6≤0.0025C.

[0083] At this time, the fan blade has the following multiple situations, the first through holes 14 are arranged in an array, and the first through holes 14 have the following three situations: the first situation is that the spacing between two adjacent first through holes 14 in the first direction X is L4. The second situation is that the spacing between two adjacent first through holes 14 in the second direction Y is L4. The third situation is that the spacing between two adjacent first through holes 14 in the first direction X is L4, and the spacing between two adjacent first through holes 14 in the second direction Y is L4. L4 satisfies 0.0015C≤L4≤0.0025C.

[0084] The second through holes 15 are arranged in an array, and the second through holes 15 have the following three conditions: the first condition is that the spacing between two adjacent second through holes 15 in the first direction X is L5. The second condition is that the spacing between two adjacent second through holes 15 in the second direction Y is L5. The third condition is that the spacing between two adjacent second through holes 15 in the first direction X is L5, and the spacing between two adjacent second through holes 15 in the second direction Y is L5. L5 satisfies 0.0015C≤L5≤0.0025C.

[0085] The plurality of third through holes 21 are arranged in one circle along the outer circumference of the sawtooth 20, and the spacing between two adjacent third through holes 21 is L6, satisfying 0.0015C≤L6≤0.0025C. When the plurality of third through holes 21 are arranged in at least two circles along the outer circumference of the sawtooth 20, the spacing between two adjacent third through holes 21 along the outer circumference of the sawtooth 20 is L6; and / or the minimum spacing between two adjacent third through holes 21 is L6, and satisfying 0.0015C≤L6≤0.0025C.

[0086] At this time, the three situations of the first through hole 14 in the fan blade, the three situations of the second through hole 15, and the multiple situations of the third through hole 21 can be combined in any way.

[0087] Further, when L4 satisfies 0.0015C≤L4≤0.0025C, the first through hole 14 can achieve a better noise reduction effect. Specifically, L4 is set according to the use requirements, and the embodiment of the present application does not specifically limit this. For example, L4 is 0.0015C, L4 is 0.0016C, L4 is 0.0017C, L4 is 0.0019C, L4 is 0.002C, L4 is 0.0021C, L4 is 0.0023C, L4 is 0.0024C, and L4 is 0.0025C.

[0088] Further, when L5 satisfies 0.0015C≤L5≤0.0025C, the second through hole 15 can achieve a better noise reduction effect. Specifically, L5 is set according to the use requirements, and the embodiment of the present application does not specifically limit this. For example, L5 is 0.0015C, L5 is 0.0016C, L5 is 0.0017C, L5 is 0.0019C, L5 is 0.002C, L5 is 0.0021C, L5 is 0.0023C, L5 is 0.0024C, and L5 is 0.0025C.

[0089] Further, when L6 satisfies 0.0015C≤L6≤0.0025C, the third through hole 21 can achieve a better noise reduction effect. Specifically, L6 is set according to the use requirements, and the embodiment of the present application does not specifically limit this. For example, L6 is 0.0015C, L6 is 0.0016C, L6 is 0.0017C, L6 is 0.0019C, L6 is 0.002C, L6 is 0.0021C, L6 is 0.0023C, L6 is 0.0024C, and L6 is 0.0025C.

[0090] Optional, see Figure 3 As shown, the fan blade is an owl wing 50% cross-section airfoil. The blade body 10 is an owl wing, i.e., a long-eared owl wing, after unfolding along the 50% spanwise cross-section of the wing, from the wing root to the wing tip 50%.

[0091] In the embodiment of the present application, when the fan blade is an owl wing 50% cross-section airfoil, there is a sufficient pressure difference between the pressure surface 12 and the suction surface 11 of the fan blade, which improves the aerodynamic performance of the fan blade and concentrates the pressure distribution, and the pressure pulsation is concentrated on the leading edge of the fan blade.

[0092] Optional, see Figure 4 and Figure 6 As shown, in the second direction Y, the connection between the end of the sawtooth 20 in the positive direction of the second direction Y and the end of the blade body 10 in the negative direction of the second direction Y is located at N, satisfying 0.08C≤N≤0.12C, wherein the length of the fan blade in the second direction Y is C. At this time, the position of the trough of the sawtooth 20 in the second direction Y of the fan blade is located at N, satisfying 0.08C≤N≤0.12C. When the sawtooth 20 of the present application is in the above position, the pressure difference between the upper and lower surfaces of the fan blade can be increased to improve the aerodynamic performance of the blade.

[0093] Specifically, the position N of the sawtooth 20 in the second direction Y of the fan blade is specifically set according to the use requirements, and the embodiment of the present application does not specifically limit this. For example, N is 0.08C, N is 0.083C, N is 0.085C, N is 0.087C, N is 0.09C, N is 0.095C, N is 0.1C, N is 0.105C, N is 0.11C, N is 0.115C, and N is 0.12C.

[0094] Optional, see Figure 3 As shown, in the third direction Z, the thickness of the connection between the end of the sawtooth 20 in the positive direction of the second direction Y and the end of the blade body 10 in the negative direction of the second direction Y is H, satisfying 0.08C≤H≤0.12C, wherein the length of the fan blade in the second direction Y is C. That is, the thickness at the position N is H. In the present application, when the thickness of the connection between the end of the sawtooth 20 in the positive direction of the second direction Y and the end of the blade body 10 in the negative direction of the second direction Y is within the above range, the pressure difference between the upper and lower surfaces of the fan blade can be increased to improve the aerodynamic performance of the blade.

[0095] Specifically, the thickness H of the connection between the end of the sawtooth 20 in the positive direction of the second direction Y and the end of the blade body 10 in the negative direction of the second direction Y is specifically set according to the use requirements, and the embodiment of the present application does not specifically limit this. For example, H is 0.08C, H is 0.083C, H is 0.085C, H is 0.087C, H is 0.09C, H is 0.095C, H is 0.1C, H is 0.105C, H is 0.11C, H is 0.115C, and H is 0.12C.

[0096] Optional, see Figure 6As shown, in the second direction Y, the fitting formula of the suction surface 11 of the blade body 10 is: y=a1x+a2x2+a3x3+a4x4+a5x5+a6x6+c1; wherein, a1=-0.704±0.145, a2=0.203±0.145, a3=-0.019±0.00571, a4=9.50971E-4±3.47592E-4, a5=-2.33032E-5±1.00263E-5, a6=2.25073E-7±1.10087E-7, c1=0.98819±0.12741, x is the horizontal coordinate, and y is the vertical coordinate.

[0097] Furthermore, the suction surface 11 is formed by the fitting formula, points are taken on the suction surface 11 to form a fitting profile, and the pressure concentration points and surface pressure difference are analyzed by simulation. The suction surface 11 formed by the fitting formula is the optimal profile structure.

[0098] Among them, refer to Figure 4 and Figure 6 As shown, in the second direction Y, the suction surface 11 at the leading edge of the fan blade has a concave arc structure.

[0099] In a specific embodiment of the fan blade of the present application, the fan blade has the following structure.

[0100] Reference Figure 4 As shown, the fan blade is an owl wing 50% cross-section airfoil, which has good aerodynamic and acoustic performance. The leading edge thickness of the owl wing 50% cross-section airfoil is relatively large, and the pressure is concentrated in the 30% area in the second direction Y. Fluid simulation is used to optimize the suction surface 11 of the owl wing 50% cross-section airfoil. In the second direction, the suction surface 11 of the 30% area of ​​the leading edge of the fan blade is thinned. After thinning, the 30% area of ​​the leading edge of the fan blade is a √-shaped structure. Figure 6 As shown, the bending part of the √-shaped structure is located at M, M is 0.25C; wherein, in the second direction Y, the length of the fan blade is C. After thinning, the thickness of the connection between the end of the sawtooth 20 in the positive direction of the second direction Y and the end of the blade body 10 in the negative direction of the second direction Y in the third direction Z is H, H is 0.1C. With the above structure of the fan blade, the leading edge thickness of the fan blade is reduced, which can increase the pressure difference between the suction surface 11 and the pressure surface 12, improve the aerodynamic performance of the fan blade profile, and move the pressure concentration point to the leading edge area of ​​the fan blade.

[0101] The leading edge of the fan blade is provided with a sawtooth 20, and the sawtooth 20 is an asymmetric sawtooth structure, that is, in the first direction X, the tooth tip 23 of the sawtooth 20 is arranged to deviate from the center line of the sawtooth 20. The sawtooth 20 can improve the noise generated by the contact and impact of the leading edge of the fan blade with turbulence. The width of the sawtooth 20 in the first direction X is W, and the length of the sawtooth 20 in the second direction Y is L1, L1 is 0.1c, and W is 0.07c. The fan blade includes a sawtooth 20 and a blade body 10, and the end of the sawtooth 20 in the positive direction of the second direction Y is connected to the end of the blade body 10 in the negative direction of the second direction Y. The surfaces of the sawtooth 20 and the blade body 10 are both smooth curved surfaces, and the connection between the sawtooth 20 and the blade body 10 is also smoothly transitioned. A third through hole 21 is provided around the sawtooth 20.

[0102] The fan blade has a suction surface 11 and a pressure surface 12 arranged opposite to each other in the third direction, wherein the first noise reduction area 17 of the suction surface 11 is provided with a first through hole 14, and the second noise reduction area 18 of the pressure surface 12 is provided with a second through hole 15. In the second direction Y, the length of the first noise reduction area 17 is L2, and the length of the second noise reduction area 18 is L3. L2 is 0.1C, and L3 is 0.05c.

[0103] The first through hole 14, the second through hole 15, and the third through hole 21 are all through holes, and the diameter of the holes is 0.008c. A plurality of third through holes 21 are arranged around the outer circumference of the sawtooth 20, and the hole spacing between two adjacent third through holes 21 is 0.002c. The plurality of third through holes 21 are used to reduce the pressure pulsation in the outer edge area of ​​the sawtooth 20, thereby reducing its noise source.

[0104] A plurality of first through holes 14 are arranged along the first direction X and the second direction Y, and the spacing between two adjacent first through holes 14 in the first direction X and the spacing between two adjacent first through holes 14 in the second direction Y are both 0.002c. A plurality of second through holes 15 are arranged along the first direction X and the second direction Y, and the spacing between two adjacent second through holes 15 in the first direction X and the spacing between two adjacent second through holes 15 in the second direction Y are both 0.002c. A plurality of first through holes 14 and a plurality of second through holes 15 are concentrated in the extension area of ​​the gap between two adjacent saw teeth 20 in the second direction Y, and in the areas on both sides of the extension area in the first direction X, that is, a plurality of first through holes 14 are arranged near the trough of the saw teeth 20. A plurality of first through holes 14, a plurality of second through holes 15, and a connecting channel 16 connecting all the first through holes 14 and all the second through holes 15 are used together to improve the pressure concentration problem caused by the saw teeth 20 and reduce the additional high-frequency noise generated.

[0105] Reference Figure 5As shown, in the embodiment of the present application, although the sawtooth 20 can effectively reduce the turbulent inflow noise, it will generate stress concentration at the trough position of the sawtooth 20, thereby generating additional high-frequency noise. The first through hole 14 is arranged in the trough area, and the first through hole 14 and the second through hole 15 are connected by a connecting channel 16. The connecting channel 16 is located in the middle of the fan blade in the thickness direction. The connecting channel 16 generates a new plane in the middle of the fan blade in the thickness direction, and concentrates part of the pressure thereon to reduce the pressure pulsation on the surface of the fan blade, thereby reducing the additional high-frequency noise generated by it. At the same time, part of the turbulence enters the first through hole 14 and directly acts on the new plane, generating an additional noise source inside the fan blade, but the noise source is affected by the structure and cannot affect the overall noise intensity of the fan blade, and the new plane will cause the suction surface 11, the pressure surface 12 and the new plane of the fan blade to continue to form a pressure difference, reducing the influence of the first through hole 14, the second through hole 15 and the connecting channel 16 on the aerodynamic performance of the fan blade.

[0106] In summary, the fan blades of the embodiments of the present application use an owl wing 50% cross-section airfoil, and improve the profile of the leading edge and pressure surface 12 of the fan blade to increase the pressure difference between the pressure surface 12 and the suction surface 11 of the fan blade, thereby improving the aerodynamic performance of the fan blade. Moreover, the leading edge of the fan blade adopts a design method of coupling an asymmetric serrated leading edge with a porous sound-absorbing structure. The asymmetric serrated leading edge redistributes the pressure pulsation at the leading edge of the fan blade, reduces the pressure at the leading edge of the fan blade, and concentrates part of the pressure pulsation to the position of the sawtooth trough; a porous sound-absorbing structure is designed in the pressure concentration area of ​​the sawtooth edge and the sawtooth trough to reduce its pressure pulsation, thereby reducing the turbulent inflow noise generated by the collision of the leading edge of the blade with the turbulent flow. Therefore, the fan blade can effectively reduce the fan noise.

[0107] The utility model discloses an axial flow fan, which comprises a fan body and the above-mentioned fan blades, wherein the fan blades are arranged in the fan body.

[0108] Among them, axial flow fans are fans whose airflow direction is in the same direction as the axis of the fan blades, such as electric fans and air conditioner outdoor fans. Axial flow fans are usually used in situations where the flow rate requirements are high and the pressure requirements are low.

[0109] When the impeller of the axial flow fan rotates, the gas enters the impeller axially from the air inlet, and then is pushed by the fan blades connected to the impeller to increase its energy, and then flows into the guide vane. The guide vane deflects the airflow direction to axial flow, and at the same time guides the gas into the diffuser, further converting the gas kinetic energy into pressure energy, and finally introduces it into the working pipeline.

[0110] In the axial flow fan of the embodiment of the utility model, a plurality of saw teeth 20 are provided at the leading edge end of the fan blade. When the fan blade rotates, the plurality of saw teeth 20 redistribute the pressure pulsation of the leading edge of the fan blade, reduce the leading edge pressure of the fan blade, and effectively reduce the inflow noise generated by the leading edge of the fan blade contacting the turbulent flow. However, the saw teeth 20 concentrate part of the pressure pulsation to the trough of the saw teeth 20. A noise reduction channel 13 is provided near the saw teeth 20 of the blade body 10. One end of the noise reduction channel 13 is located on the pressure surface 12, and the other end of the noise reduction channel 13 is located on the suction surface 11. The noise reduction channel 13 is located in the pressure concentration area of ​​the blade body 10 near the saw teeth 20. The noise reduction channel 13 can expand and disperse the pressure concentration area, reduce the pressure pulsation in the pressure concentration area, and thus reduce the noise problem caused by the pressure pulsation. Therefore, the axial flow fan has the advantage of low noise.

[0111] The embodiment of the utility model also discloses an air conditioner, which includes the above-mentioned axial flow fan. Since the axial flow fan has the advantage of low noise, it can reduce the noise of the air conditioner, thereby improving the user's satisfaction.

[0112] Air conditioners are devices that use artificial means to adjust and control the temperature, humidity, flow rate and other parameters of the ambient air in a building or structure. Air conditioners provide people with coolness and warmth, so they are widely used.

[0113] The embodiment of the present application does not specifically limit whether the air conditioner includes other structures. For example, the air conditioner may also include: a housing for arranging an axial flow fan, etc.

[0114] It should be noted that the air conditioner, the axial flow fan and the fan blade can refer to each other and have the same or similar beneficial effects as any of the aforementioned fan blades. In order to avoid repetition, they will not be described again here.

[0115] It should be noted that, in this article, relational terms such as first and second, etc. 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. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0116] Each embodiment in this specification is described in a related manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. For the embodiments of the device, electronic device, computer-readable storage medium and computer program products containing instructions, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiments.

[0117] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A fan blade having a first direction (X), a second direction (Y) and a third direction (Z) intersecting each other, characterized in that: The fan blade comprises a pressure surface (12), a suction surface (11), a blade body (10) and a plurality of saw teeth (20); one side of the fan blade in the third direction (Z) is the suction surface (11), and the other side of the fan blade in the third direction (Z) is the pressure surface (12); A plurality of saw teeth (20) are arranged along the first direction (X), and an end of the saw teeth (20) in the positive direction of the second direction (Y) is connected to an end of the blade body (10) in the negative direction of the second direction (Y); The blade body (10) is provided with a noise reduction channel (13) near the sawtooth (20), one end of the noise reduction channel (13) is located on the pressure surface (12), and the other end of the noise reduction channel (13) is located on the suction surface (11).

2. The fan blade according to claim 1, characterized in that: The noise reduction channel (13) comprises a plurality of first through holes (14), a plurality of second through holes (15), and a communication channel (16); One end of the first through hole (14) is arranged on the suction surface (11), one end of the second through hole (15) is arranged on the pressure surface (12), and the first through hole (14) is closer to the sawtooth (20) than the second through hole (15); The communication channel (16) is located in the blade body (10) and is arranged along the second direction (Y); one end of the communication channel (16) close to the saw tooth (20) is connected to the other end of all the first through holes (14); and the other end of the communication channel (16) away from the saw tooth (20) is connected to the other end of all the second through holes (15).

3. The fan blade according to claim 2, characterized in that: The suction surface (11) of the fan blade is provided with a first noise reduction area (17), the first noise reduction area (17) is in a rectangular structure, one end of the first noise reduction area (17) is close to the side of the sawtooth (20) in the first direction (X), and the other end of the first noise reduction area (17) extends toward the trailing edge of the fan blade, and the first through hole (14) is provided on the first noise reduction area (17).

4. The fan blade according to claim 3, characterized in that: In the second direction (Y), the length of the fan blade is C, and the length of the first noise reduction area (17) is L2, satisfying 0.095C≤L2≤0.105C.

5. The fan blade according to claim 3, characterized in that: The pressure surface (12) of the fan blade is provided with a second noise reduction area (18), and the second noise reduction area (18) is in a rectangular structure; In the second direction (Y), one end of the second noise reduction zone (18) is close to the first noise reduction zone (17), and the other end of the second noise reduction zone (18) extends toward the trailing edge of the fan blade, and the second through hole (15) is provided on the second noise reduction zone (18).

6. The fan blade according to claim 5, characterized in that: In the second direction (Y), the length of the fan blade is C, and the length of the second noise reduction area (18) is L3, satisfying 0.045C≤L3≤0.055C.

7. The fan blade according to claim 1, characterized in that: In the first direction (X), the tooth tip (23) of the sawtooth (20) deviates from the center line of the sawtooth (20); and the plurality of noise reduction channels (13) are close to the side edge of the sawtooth (20) in the first direction (X).

8. The fan blade according to claim 7, characterized in that: Taking a cross section parallel to the plane where the first direction (X) and the second direction (Y) are located, the sawtooth (20) is a right-angled triangle-like structure; a right-angled side of the right-angled triangle-like structure is connected to the end of the blade body (10) in the negative direction of the second direction (Y), the other right-angled side of the right-angled triangle-like structure is perpendicular to the end of the blade body (10) in the negative direction of the second direction (Y), and the hypotenuse (22) of the right-angled triangle-like structure is a curved surface convex in a direction away from the two right-angled sides.

9. The fan blade according to claim 7, characterized in that: In the second direction (Y), the length of the fan blade is C, the length of the sawtooth (20) is L1, and 0.0095C≤L1≤0.0105C.

10. The fan blade according to claim 7, characterized in that: In the second direction (Y), the length of the fan blade is C; in the first direction (X), the width of the sawtooth (20) is W, and 0.0065C≤W≤0.0075C.

11. The fan blade according to claim 2, characterized in that: A third through hole (21) is provided on the outer periphery of the sawtooth (20), one end of the third through hole (21) is located on the pressure surface (12), and the other end of the third through hole (21) is located on the suction surface (11).

12. The fan blade according to claim 11, characterized in that: The diameter of the first through hole (14) is φ1, satisfying 0.0075C≤φ1≤0.0085C; and / or the diameter of the second through hole (15) is φ2, satisfying 0.0075C≤φ2≤0.0085C; and / or the diameter of the third through hole (21) is φ3, satisfying 0.0075C≤φ3≤0.0085C; wherein the length of the fan blade in the second direction (Y) is C.

13. The fan blade according to claim 11, characterized in that: A plurality of the first through holes (14) are arranged along the first direction (X) and the second direction (Y), a distance between two adjacent first through holes (14) in the first direction (X) is L4, and / or a distance between two adjacent first through holes (14) in the second direction (Y) is L4, satisfying 0.0015C≤L4≤0.0025C; and / or, A plurality of the second through holes (15) are arranged along the first direction (X) and the second direction (Y), a distance between two adjacent second through holes (15) in the first direction (X) is L5, and / or a distance between two adjacent second through holes (15) in the second direction (Y) is L5, satisfying 0.0015C≤L5≤0.0025C; A plurality of the third through holes (21) are provided, and the plurality of the third through holes (21) are arranged along the outer periphery of the sawtooth (20), and a distance between two adjacent third through holes (21) is L6, satisfying 0.0015C≤L6≤0.0025C.

14. The fan blade according to claim 1, characterized in that: The fan blade is an airfoil with a cross-section of 50% of an owl wing.

15. The fan blade according to claim 14, characterized in that: In the second direction (Y), the connection between the end of the sawtooth (20) in the positive direction of the second direction (Y) and the end of the blade body (10) in the negative direction of the second direction (Y) is located at N, satisfying 0.08C≤N≤0.12C, wherein the length of the fan blade in the second direction (Y) is C.

16. The fan blade according to claim 1, characterized in that: In the third direction (Z), the thickness of the sawtooth (20) at the connection between the end of the sawtooth (20) in the positive direction of the second direction (Y) and the end of the blade body (10) in the negative direction of the second direction (Y) is H, satisfying 0.08C≤H≤0.12C, wherein the length of the fan blade in the second direction (Y) is C.

17. The fan blade according to claim 1, characterized in that: In the second direction (Y), the fitting formula of the suction surface (11) of the blade body (10) is: y=a1x+a2x2+a3x3+a4x4+a5x5+a6x6+c1; Among them, a1 = -0.704±0.145, a2 = 0.203±0.145, a3 = -0.019±0.00571, a4 = 9.50971E-4±3.47592E-4, a5 = -2.33032E-5±1.00263E-5, a6 = 2.25073E-7±1.10087E-7, c1 = 0.98819±0.12741, x is the horizontal coordinate and y is the vertical coordinate.

18. An axial flow fan, characterized in that: It comprises a fan body and the fan blade according to any one of claims 1 to 17, wherein the fan blade is arranged in the fan body.

19. An air conditioner, characterized in that: Including the axial flow fan as described in claim 18.

Images