A noise reduction blade and fan thereof

Abstract

The present invention provides a noise reduction blade and a fan thereof, which relates to the technical field of fan devices, including a wind wheel blade, the wind wheel blade including a blade pressure surface, a blade suction surface, a blade leading edge and a blade trailing edge; the blade leading edge adopts a corrugated noise reduction design, and the blade is designed with corrugated noise reduction in both the circumferential and axial directions from the blade tip to the blade root. The present invention designs corrugations in the circumferential and axial directions on the blade leading edge, so that the blade leading edge has airflow inlet angles of different angles from the blade tip to the blade root, so that when the airflow enters the wind wheel blade, it interacts with the blade leading edge to generate pressure pulsations in different directions, which can effectively reduce the fan inlet noise; the blade is designed with corrugations in the circumferential and axial directions from the blade tip to the blade root, so that an airflow guide flow channel from deep to shallow from the blade leading edge to the blade trailing edge can be formed on the blade pressure surface and the blade suction surface, which can increase the blade strength, and can also play a role in guiding the airflow so that the airflow flows more evenly on the blade surface, thereby achieving the effect of improving the fan efficiency and reducing noise.

Description

Technical Field

[0001] The invention relates to the technical field of fan devices, in particular to a noise reduction blade and a fan thereof. 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. Gas compression and gas delivery machinery is a machine that converts rotational mechanical energy into gas pressure energy and kinetic energy and delivers the gas. The main structural components of a fan include impeller, casing, air inlet, bracket, motor, transmission parts (bearings), etc.

[0003] When the fan is running, the conventional blades will generate eddy separation when the airflow flows through the suction surface of the blade root due to the excessive installation angle of the blade root, forming an eddy separation area that increases the fan noise, resulting in the location near the fan being unfavorable for living and working due to excessive noise; in addition, a continuous high-noise environment may also have an adverse effect on human health, such as causing hearing damage, sleep disorders and other health problems. Therefore, it is necessary to disclose a noise-reducing blade and a fan thereof to overcome the existing defects. Summary of the invention

[0004] The present invention overcomes the shortcomings of the prior art and provides a noise reduction blade and a fan thereof, which has an ingenious structure and can reduce the fan inlet noise and the fan eddy current noise.

[0005] In order to solve the above technical problems, the present invention is achieved through the following technical solutions:

[0006] A noise reduction blade includes a wind rotor blade, and the wind rotor blade includes a blade pressure surface, a blade suction surface, a blade leading edge, and a blade trailing edge. The leading edge of the blade adopts a corrugated noise reduction design, which is set so that the leading edge of the blade is designed with corrugations in the circumferential and axial directions, so that the leading edge of the blade has airflow inlet angles of different angles from the tip to the root, so that when the airflow enters the wind rotor blade, it interacts with the leading edge of the blade to produce pressure pulsations in different directions, which can effectively reduce the fan inlet noise. In addition, the blade is designed with corrugations in the circumferential and axial directions from the tip to the root; this setting makes the blade designed with corrugations in the circumferential and axial directions from the tip to the root, so that an airflow guide flow channel from the leading edge of the blade to the trailing edge of the blade can be formed on the pressure surface and the suction surface of the blade, which can increase the strength of the blade, and can also play a role in guiding the airflow to make the airflow flow more evenly on the surface of the blade, so as to improve the efficiency of the fan and reduce noise. Multiple raised Venturi guide grids are designed on the suction surface of the blade. The inlet area of ​​the Venturi guide grid is larger than the outlet area. The middle section of the flow channel gradually decreases from the inlet to the outlet to form a Venturi flow channel. This arrangement increases the airflow velocity when the airflow passes through the Venturi guide grid, making it difficult for the airflow to break away from the blade surface and generate vortex noise, which can effectively reduce the airflow shedding on the suction surface of the blade and thus reduce the fan noise. The airflow guide flow channel formed by the corrugated design of the leading edge of the blade matches the inlet of the Venturi guide grid, which can play a just right airflow guiding role.

[0007] Furthermore, the number of corrugations on the leading edge of the blade is n1, where n1≧1, the corrugation starting from the tip of the blade is the first corrugation, and the corrugation height and length gradually increase from the tip of the blade to the root of the blade; the above-mentioned downward arrangement refers to the second corrugation, the second corrugation, etc.;

[0008] Furthermore, the first circumferential corrugation height of the leading edge of the blade is H1, and the last corrugation height is H2, wherein H2>H1, 2H1≦H2≦5H1, and the circumferential corrugation height increases gradually from the first corrugation to the last corrugation;

[0009] The first circumferential corrugation length of the blade leading edge is L1, and the last corrugation length is L2, wherein L2>L1, L1≦L2≦2L1, and the circumferential corrugation length increases gradually from the first corrugation to the last corrugation.

[0010] Furthermore, the first axial corrugation height of the leading edge of the blade is h1, and the last corrugation height is h2, wherein h2>h1, h1≦h2≦2h1, and the axial corrugation height gradually increases from the first corrugation to the last corrugation; if the axial corrugation height is too large, the airflow guide channel on the blade surface will be too large, affecting the airflow flow on the blade surface.

[0011] Furthermore, the number of Venturi guide grids on the suction surface of the blade is n2, where n2≧2, a Venturi guide channel is formed between the two Venturi guide grids, the Venturi guide grid starting from the tip position is the first Venturi guide grid, and the Venturi guide grids are arranged in sequence downward; the downward sequence mentioned above refers to the second Venturi guide grid, the third Venturi guide grid, and so on.

[0012] The length of the first Venturi guide grid on the suction surface of the blade is L3, the length of the last Venturi guide grid is L4, the length of the blade tip is L, 0.2L≦L4≦0.6L, 0.3L4≦L3≦0.8L4, and the length of the Venturi guide grid gradually decreases from the first guide grid to the last Venturi guide grid.

[0013] Furthermore, the inlet width of the first Venturi guide channel on the suction surface of the blade is H3, and the inlet width of the last Venturi guide channel is H4, wherein H4>H3, and the inlet width of the Venturi guide channel gradually increases from top to bottom.

[0014] Furthermore, the outlet width of the first Venturi guide channel on the suction surface of the blade is H5, and the outlet width of the last Venturi guide channel is H6, wherein H5>H6, and the outlet width of the Venturi guide channel gradually increases and decreases from top to bottom.

[0015] Furthermore, the inlet width of the first Venturi guide channel on the suction surface of the blade is H3, and the outlet width is H5, wherein 1<H5 / H3≦3, and the ratio of the inlet and outlet widths of the Venturi guide channel increases as it goes downward.

[0016] Furthermore, the Venturi guide grid of the suction surface of the blade gradually tilts downward from the leading edge to the trailing edge of the blade, the first Venturi guide grid has an inclination angle of a1, and the last Venturi guide grid has an inclination angle of a2, wherein 20°≦a1<a2≦70°.

[0017] The present invention also seeks to protect a wind fan, comprising a wind wheel, a motor, an air guide ring and a fan bracket, wherein the wind wheel comprises a wind wheel hub and the noise reduction blades connected to the wind wheel hub; the wind wheel is assembled with the motor through a mounting hole of the wind wheel hub, and the motor is mounted on the air guide ring through the fan bracket, and the air guide ring can simultaneously support the operation of the wind wheel and rectify the airflow.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The present invention adopts a corrugated design on the leading edge of the blade, which can effectively modulate the inlet airflow pressure pulsation and effectively reduce the fan inlet noise; the design of a Venturi guide grid on the pressure surface of the blade can increase the airflow flow velocity in the flow channel, reduce the airflow separation on the suction surface of the blade, and thus reduce the fan vortex noise. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are used to provide a further understanding of the present invention and are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation of the present invention. In the accompanying drawings:

[0021] Figure 1 is a front view of the wind wheel of the present invention;

[0022] Figure 2 is a side view of the wind wheel of the present invention;

[0023] Figures 3 to 5 is a front view of the wind wheel blade described in this embodiment;

[0024] Figure 6 is a side view of the blade described in this embodiment;

[0025] Figure 7 This is the front view of the fan;

[0026] Figure 8 This is a side view of the fan.

[0027] In the figure: 1. wind wheel; 11. wind wheel blade 11; 111. blade pressure surface 111; 112. blade suction surface; 113. blade leading edge; 114. blade trailing edge; 115. Venturi guide grid; 2. motor; 3. air guide ring; 4. fan bracket. DETAILED DESCRIPTION

[0028] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0029] like Figures 1 to 6 As shown, a noise reduction blade comprises a wind rotor blade 11, and the wind rotor blade 11 comprises a blade pressure surface 111, a blade suction surface 112, a blade leading edge 113 and a blade trailing edge 114; the blade leading edge 113 adopts a corrugated noise reduction design, and the blade is designed with corrugated noise reduction in both the circumferential and axial directions from the blade tip to the blade root, and the blade leading edge 113 is designed with corrugations in the circumferential and axial directions, so that the blade leading edge has airflow inlet angles of different angles from the blade tip to the blade root, so that when the airflow enters the wind rotor blade, it interacts with the blade leading edge to generate pressure pulsations in different directions, which can effectively reduce the fan inlet noise; the blade is designed with corrugations in both the circumferential and axial directions from the blade tip to the blade root, so that an airflow guide flow channel from deep to shallow from the blade leading edge 113 to the blade trailing edge 114 can be formed on the blade pressure surface 111 and the blade suction surface 112, which can increase the blade strength, and can also play a role in guiding the airflow so that the airflow flows more evenly on the blade surface, thereby improving the fan efficiency and reducing the noise;

[0030] A plurality of raised Venturi guide grids 115 are designed on the suction surface 112 of the blade, wherein the inlet area of ​​the Venturi guide grid 115 is larger than the outlet area, and the middle section of the flow channel gradually decreases from the inlet to the outlet to form a Venturi flow channel. When the airflow passes through the Venturi guide grid 115, the airflow velocity is increased, making it difficult for the airflow to separate from the blade surface and generate eddy noise, which can effectively reduce the airflow shedding on the suction surface of the blade and thus reduce the fan noise; the airflow guide flow channel formed by the corrugated design of the leading edge of the blade matches the inlet of the Venturi guide grid, and can play a just right airflow guiding role.

[0031] The number of corrugations of the leading edge 113 of the blade is n1, where n1≧1, the corrugation starting from the tip position is the first corrugation, and the corrugation height and length gradually increase from the tip to the root; the above-mentioned downward order refers to the second corrugation, the third corrugation, etc.; the leading edge 113 of the blade is provided with multiple corrugations, so that the leading edge 113 of the blade has different airflow inlet angles from the tip to the root, so that when the airflow enters the wind wheel blade, it interacts with the leading edge of the blade to generate pressure pulsations in different directions, which can effectively reduce the fan inlet noise;

[0032] The first circumferential corrugation height of the blade leading edge 113 is H1, and the last corrugation height is H2, where H2>H1, 2H1≦H2≦5H1, and the circumferential corrugation height gradually increases from the first corrugation to the last corrugation; since the inlet airflow velocity at the blade tip is high, the corrugation height at the blade tip is small, the inlet airflow velocity at the blade root is low, and the corrugation height at the blade root is high, the speed of the inlet airflow at the blade leading edge can be effectively and evenly adjusted, and the vortex generated at the inlet of the blade leading edge can be reduced. If the circumferential corrugation height is too large, the airflow guide flow channel on the blade surface will be too large, affecting the airflow flow on the blade surface.

[0033] The first circumferential corrugation length of the blade leading edge 113 is L1, and the last corrugation length is L2, where L2>L1, L1≦L2≦2L1, and the circumferential corrugation length gradually increases from the first corrugation to the last corrugation. Since the airflow velocity at the blade tip is high, the corrugation length at the blade tip is small, the corrugation density is high, and the airflow velocity at the blade root is low, the corrugation density is low, the velocity of the airflow at the blade leading edge inlet can be effectively and evenly adjusted to reduce the generation of vortices at the blade leading edge inlet.

[0034] The first axial corrugation height of the blade leading edge 113 is h1, and the last corrugation height is h2, where h2>h1, h1≦h2≦2h1, and the axial corrugation height gradually increases from the first corrugation to the last corrugation; since the inlet airflow velocity at the blade tip is high, the corrugation height at the blade tip is small, the inlet airflow velocity at the blade root is low, and the corrugation height at the blade root is high, the speed of the inlet airflow at the blade leading edge can be effectively and evenly adjusted, and the vortex generation at the inlet of the blade leading edge can be reduced. If the axial corrugation height is too large, the airflow guide flow channel on the blade surface will be too large, affecting the airflow flow on the blade surface.

[0035] The number of Venturi guide grids 115 on the suction surface 112 of the blade is n2, where n2≧2, and a Venturi guide channel is formed between the two Venturi guide grids 115. The Venturi guide grid 115 starting from the tip position is the first Venturi guide grid, and the Venturi guide grids are arranged in sequence downward; the downward sequence mentioned above refers to the second Venturi guide grid, the third Venturi guide grid, and so on.

[0036] The length of the first Venturi guide grid 115 on the suction surface 112 of the blade is L3, the length of the last Venturi guide grid 115 is L4, the length of the blade tip is L, and 0.2L≦L4≦0.6L, 0.3L4≦L3≦0.8L4, and the length of the Venturi guide grid 115 gradually decreases from the first Venturi guide grid to the last Venturi guide grid. Since the chord length of the blade tip section is longer, the airflow shedding position on the suction surface of the blade will be moved forward compared to the airflow shedding position of the section with a shorter chord length. If the guide grid length is too long, it will affect the airflow flow on the suction surface of the blade, and if the guide grid length is too short, it will not reduce the airflow shedding on the suction surface of the blade. The guide grid length at the tip of the blade is longer than the guide grid length at the root of the blade, so as to effectively reduce the airflow separation on the suction surface of the blade, thereby reducing the fan noise;

[0037] The inlet width of the first Venturi flow guide channel on the suction surface 112 of the blade is H3, and the inlet width of the last Venturi flow guide channel is H4, where H4>H3, and the inlet width of the Venturi flow guide channel gradually increases from top to bottom. The airflow velocity at the tip of the blade is high, and the inlet width of the flow guide channel at the tip of the blade is too large, which will cause a sudden change in the airflow when the airflow enters the flow channel, thereby causing airflow separation, affecting the guiding function of the guide grid; the airflow velocity at the root of the blade is low, and the inlet width of the flow guide channel at the root of the blade is large, and the airflow entering the flow guide channel will not only not cause airflow separation, but also better play the role of airflow acceleration, thereby reducing the airflow shedding at the root of the blade and reducing the fan noise;

[0038] The outlet width of the first Venturi guide channel on the suction surface 112 of the blade is H5, and the outlet width of the last Venturi guide channel is H6, where H5>H6, and the outlet width of the Venturi guide channel gradually increases and decreases from top to bottom. The airflow velocity at the tip of the blade is high, and the airflow velocity at the root of the blade is low. The outlet width of the Venturi guide channel at the tip of the blade is greater than the outlet width of the Venturi guide channel at the root of the blade, which can make the airflow on the suction surface of the blade from the tip to the root of the blade through the Venturi guide grid uniform, making the pressure distribution on the suction surface of the blade more uniform, thereby reducing fan noise and improving fan efficiency;

[0039] The inlet width of the first Venturi guide channel on the suction surface 112 of the blade is H3, and the outlet width is H5, where 1<H5 / H3≦3, and the ratio of the inlet and outlet widths of the Venturi guide channel increases as it goes down. The airflow velocity at the tip of the blade is high, and the airflow velocity at the root of the blade is low. The ratio of the inlet and outlet widths of the Venturi guide channel increases as it goes down, which can make the airflow on the suction surface of the blade from the tip to the root through the Venturi guide grid have a uniform air outlet velocity, making the pressure distribution on the suction surface of the blade more uniform, thereby reducing fan noise and improving fan efficiency;

[0040] The Venturi guide grid 115 on the suction surface 112 of the blade gradually tilts downward from the leading edge to the trailing edge of the blade. The first Venturi guide grid 115 tilts at an angle of a1, and the last Venturi guide grid 115 tilts at an angle of a2, wherein 20°≦a1<a2≦70°. The airflow velocity at the tip of the blade is high, and the airflow velocity at the root of the blade is low. The tilt angle of the Venturi guide grid at the tip of the blade is smaller than the tilt angle of the Venturi guide grid at the root of the blade, which can make the airflow on the suction surface of the blade uniform from the tip to the root through the Venturi guide grid, making the pressure distribution on the suction surface of the blade more uniform, thereby reducing fan noise and improving fan efficiency;

[0041] like Figures 7 and 8 As shown, the present invention also requests protection for a wind turbine, including a wind wheel 1, a motor 2, an air guide ring 3 and a fan bracket 4, the wind wheel 1 including a wind wheel hub 12 and noise reduction blades connected to the wind wheel hub 12; the wind wheel 1 is assembled with the motor 2 through the wind wheel hub mounting hole 121, the motor 2 is mounted on the air guide ring 3 through the fan bracket 4, and the air guide ring 3 can simultaneously support the operation of the wind wheel and rectify the airflow.

[0042] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. However, any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A noise reduction blade, characterized in that: The invention comprises a wind rotor blade (11), wherein the wind rotor blade (11) comprises a blade pressure surface (111), a blade suction surface (112), a blade leading edge (113) and a blade trailing edge (114); the blade leading edge (113) adopts a corrugated noise reduction design, and the blade is designed with corrugated noise reduction in both the circumferential direction and the axial direction from the blade tip to the blade root; a plurality of raised Venturi guide grids (115) are designed on the blade suction surface (112), wherein the inlet area of ​​the Venturi guide grid (115) is larger than the outlet area, and the middle section of the flow channel gradually decreases from the inlet to the outlet, thereby forming a Venturi flow channel; the airflow guiding flow channel formed by the corrugated design of the blade leading edge (113) matches the inlet of the Venturi guide grid (115), thereby playing a perfect airflow guiding role.

2. The noise reduction blade according to claim 1, characterized in that: The number of corrugations on the leading edge (113) of the blade is n1, where n1≧1, the corrugation starting from the blade tip is the first corrugation, and the corrugation height and length gradually increase from the blade tip to the blade root.

3. The noise reduction blade according to claim 1, characterized in that: The first circumferential corrugation height of the blade leading edge (113) is H1, and the last corrugation height is H2, wherein H2>H1, 2H1≦H2≦5H1, and the circumferential corrugation height gradually increases from the first corrugation to the last corrugation; The blade leading edge (113) has a first circumferential corrugation length L1, and a last corrugation length L2, wherein L2>L1, L1≦L2≦2L1, and the circumferential corrugation length increases gradually from the first corrugation to the last corrugation.

4. The noise reduction blade according to claim 1, characterized in that: The first axial corrugation height of the blade leading edge (113) is h1, and the last corrugation height is h2, wherein h2>h1, h1≦h2≦2h1, and the axial corrugation height gradually increases from the first corrugation to the last corrugation; if the axial corrugation height is too large, the airflow guide flow channel on the blade surface will be too large, affecting the airflow flow on the blade surface.

5. The noise reduction blade according to claim 1, characterized in that: The number of Venturi guide grids (115) on the suction surface (112) of the blade is n2, where n2≧2, a Venturi guide channel is formed between two Venturi guide grids (115), the Venturi guide grid (115) starting from the blade tip position is the first guide grid, and the Venturi guide grids (115) are arranged in order downwards; The length of the Venturi guide grid (115) on the suction surface (112) of the blade is L3, the length of the last Venturi guide grid (115) is L4, the length of the blade tip is L, wherein 0.2L≦L4≦0.6L, 0.3L4≦L3≦0.8L4, and the length of the Venturi guide grid (115) gradually decreases from the first guide grid to the last guide grid.

6. The noise reduction blade according to claim 5, characterized in that: The inlet width of the first Venturi guide channel in the blade suction surface (112) is H3, and the inlet width of the last Venturi guide channel is H4, wherein H4>H3, and the inlet width of the Venturi guide channel gradually increases from top to bottom.

7. The noise reduction blade according to claim 5, characterized in that: The first Venturi guide channel outlet width of the blade suction surface (112) is H5, and the last Venturi guide channel outlet width is H6, wherein H5>H6, and the Venturi guide channel outlet width gradually increases and decreases from top to bottom.

8. The noise reduction blade according to claim 1, characterized in that: The inlet width of the first Venturi guide channel of the blade suction surface (112) is H3, and the outlet width is H5, wherein 1<H5 / H3≦3, and the ratio of the inlet and outlet widths of the Venturi guide channel increases as it goes downward.

9. The noise reduction blade according to claim 1, characterized in that: The Venturi guide fence (115) of the blade suction surface (112) gradually tilts downward from the leading edge of the blade to the trailing edge of the blade, the first guide fence tilting angle is a1, the last guide fence tilting angle is a2, and 20°≦a1<a2≦70°.

10. A fan, comprising a wind wheel (1), a motor (2), an air guide ring (3) and a fan bracket (4), the wind wheel (1) comprising a wind wheel hub (12) and a noise reduction blade according to any one of claims 1 to 9 connected to the wind wheel hub (12); the wind wheel (1) is assembled with the motor (2) through a wind wheel hub mounting hole (121), the motor (2) is mounted on the air guide ring (3) through the fan bracket (4), and the air guide ring (3) can simultaneously support the operation of the wind wheel and rectify the airflow.

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