CN111980964A

CN111980964A - Blade, axial fan blade and fan

Info

Publication number: CN111980964A
Application number: CN202011029925.0A
Authority: CN
Inventors: 梁浩; 柳洲; 陈宇强; 王勇; 刘建优; 张驰
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai
Priority date: 2020-09-25
Filing date: 2020-09-25
Publication date: 2020-11-24
Also published as: WO2022062430A1

Abstract

The invention relates to the technical field of fans, in particular to a blade, an axial flow fan blade and a fan, wherein the blade comprises a pressure surface, a suction surface, a blade root part, a blade top part, a front edge part and a rear edge part, a cylindrical surface where the blade root part is located is defined as a blade root primitive surface, a cylindrical surface where the blade top part is located is a blade top primitive surface, a cylindrical surface located between the blade root primitive surface and the blade top primitive surface is an 1/2 primitive surface, and a cylindrical surface located between the blade top primitive surface and a 1/2 primitive surface is a 3/4 primitive surface; the maximum distance between the leading edge and the trailing edge at the blade root element surface is l1, the maximum distance between the leading edge and the trailing edge at the element surface 1/2 is l2, the maximum distance between the leading edge and the trailing edge at the element surface 3/4 is l3, the maximum distance between the leading edge and the trailing edge at the element surface top is l4, and l1 < l2 < l3 < l 4. The wind speed at the outlet can be effectively improved, the pneumatic performance of the blade is matched with that of the motor, and the air quantity of the fan made of the blade is guaranteed.

Description

Blade, axial fan blade and fan

Technical Field

The invention relates to the technical field of fans, in particular to a blade, an axial flow fan blade and a fan.

Background

The axial flow fan blade is used as a core component of the electric fan and plays a decisive role in the air quantity and the noise of the whole fan. When designing the blade profile, the common axial flow fan blade mostly adopts a continuous smooth curved surface model, as shown in fig. 1 to 3, the profile of each section is in smooth transition, and the camber is small. The blade profile design is fast, the air flow is directional and the air is diffused.

When the fan works, the motor drives the fan blades to rotate at a high speed to drive airflow to flow out forwards. In order to ensure that the fan has high energy efficiency, namely the ratio of the work of the fan to the power consumed by the motor is the maximum, the reasonable matching of the fan blades and the load of the motor is very critical. If the pneumatic performance of the fan blade is not matched with that of the motor, the actual working point of the motor is in an over-load running state, the main phase current of the motor is increased, and the auxiliary phase current of the motor is increased when the motor is in light-load running. The main and auxiliary phase currents of the motor are increased, the copper consumption is increased, and the temperature rise is increased. In order to reduce the motor temperature rise, the motor cost is increased correspondingly. Therefore, the fan blades are reasonably designed, the pneumatic performance of the fan blades is matched with that of the motor, the motor can run efficiently, and the cost of the motor is reduced.

The applicant finds that the installation angle and the bending degree of each section profile of the fan blade are the key for determining the aerodynamic performance of the fan blade in research. The sectional profile of the fan blade is reasonably adjusted, so that the outlet air speed can be effectively improved, and the air quantity of the electric fan is ensured.

Disclosure of Invention

Therefore, the invention aims to provide a blade, an axial flow fan blade and a fan, wherein the pneumatic performance of the blade, the axial flow fan blade and the fan can be matched with a motor.

The invention provides a blade, which comprises a pressure surface, a suction surface, a blade root, a blade top, a front edge part and a rear edge part, wherein a cylindrical surface where the blade root is located is defined as a blade root primitive surface, the cylindrical surface where the blade top is located is a blade top primitive surface, the cylindrical surface between the blade root primitive surface and the blade top primitive surface is an 1/2 primitive surface, and the cylindrical surface between the blade top primitive surface and the 1/2 primitive surface is an 3/4 primitive surface;

the maximum distance between the leading edge portion and the trailing edge portion at the root element surface is l1, the maximum distance between the leading edge portion and the trailing edge portion at the 1/2 element surface is l2, the maximum distance between the leading edge portion and the trailing edge portion at the 3/4 element surface is l3, the maximum distance between the leading edge portion and the trailing edge portion at the tip element surface is l4, and l1 < l2 < l3 < l 4.

35mm≤l1≤45mm，85mm≤l4≤95mm。

Above the 1/2 cell face, the pressure face is provided with a concave portion such that the suction face comprises a convex surface.

The recess is recessed to a maximum extent in a region between the center line of the blade to the trailing edge portion.

At the blade root element surface, an included angle between a connecting line of the front edge part and the rear edge part and a tangent line of the front edge part on the blade root element surface is alpha 1; at the 1/2 cell plane, the line connecting the leading edge portion and the trailing edge portion has an included angle α 2 with the tangent of the leading edge portion at the 1/2 cell plane; at the 3/4 cell plane, the line connecting the leading edge portion and the trailing edge portion has an angle α 3 with the tangent of the leading edge portion at the 3/4 cell plane; at the blade top element surface, an included angle between a connecting line of the front edge part and the rear edge part and a tangent line of the front edge part on the blade top element surface is alpha 4; alpha 1 > alpha 2 > alpha 3 > alpha 4.

35°≤α1≤45°，5°≤α4≤15°。

A maximum distance f1 between an inner side surface of a cross section of the blade and a line connecting the leading edge portion and the trailing edge portion at the blade root element surface; at the 1/2 elementary faces, the maximum distance between the inner side face of the cross section of the blade and the line connecting the leading edge portion and the trailing edge portion is f 2; at the 3/4 elementary faces, the maximum distance between the inner side face of the cross section of the blade and the line connecting the leading edge portion and the trailing edge portion is f 3; at the tip element surface, the maximum distance between the inner side surface of the cross section of the blade and the line connecting the leading edge portion and the trailing edge portion is f4, f3 > f1, f3 > f2, f3 > f 4.

f1＝f4，f2＝1.5f1，f3＝2f1。

The blades are swept back.

The sweepback angle of the blade is theta, and theta is more than or equal to 8 degrees and less than or equal to 15 degrees.

Above the 3/4 cell face, the suction face has a concave portion so that the pressure face has a convex surface.

The top end of the front edge part of the blade is provided with a blade tip angle, the radius of the blade tip angle is R, and R is more than or equal to 3mm and less than or equal to 6 mm.

The invention also provides an axial flow fan blade which comprises a hub and a plurality of blades which are uniformly distributed along the circumferential direction of the hub.

The diameter of the hub is D, the outer diameter of the axial flow fan blade is D, and D/D is more than or equal to 0.25 and less than or equal to 0.3.

The number of the blades is 7.

The invention also provides a fan which comprises the axial flow fan blade.

The technical scheme of the invention has the following advantages:

1. according to the blade provided by the invention, the wind speed at the outlet can be effectively increased by enabling l1 to be more than l2 to be more than l3 to be more than l4, the pneumatic performance of the blade is matched with a motor, and the wind volume of a fan made of the blade is ensured.

2. According to the blade provided by the invention, the pressure surface is provided with the concave part above the 1/2 element surface, so that the suction surface comprises the convex surface, the static pressure of the pressure surface of the blade can be effectively improved, the working capacity of the blade is improved, the outlet wind speed is further improved, and the blade efficiency is increased.

3. According to the blade provided by the invention, in the area between the central line of the blade and the rear edge part, the concave degree of the concave part is maximum, the working capacity of the middle rear part of the blade can be increased, and the aerodynamic performance is further improved.

4. In the blade provided by the invention, at the blade root element surface, the included angle between the connecting line of the front edge part and the rear edge part and the tangent line of the front edge part on the blade root element surface is alpha 1; at the 1/2 cell plane, the line connecting the leading edge portion and the trailing edge portion has an included angle α 2 with the tangent of the leading edge portion at the 1/2 cell plane; at the 3/4 cell plane, the line connecting the leading edge portion and the trailing edge portion has an angle α 3 with the tangent of the leading edge portion at the 3/4 cell plane; at the blade top element surface, an included angle between a connecting line of the front edge part and the rear edge part and a tangent line of the front edge part on the blade top element surface is alpha 4; alpha 1 is more than alpha 2 and more than alpha 3 and more than alpha 4, the installation angle of the blade root is large, the strength of the blade can be effectively ensured, and the load is not increased greatly.

5. In the blade provided by the invention, at the blade root element surface, the maximum distance between the inner side surface of the cross section of the blade and the connecting line of the front edge part and the rear edge part is f 1; at the 1/2 elementary faces, the maximum distance between the inner side face of the cross section of the blade and the line connecting the leading edge portion and the trailing edge portion is f 2; at the 3/4 elementary faces, the maximum distance between the inner side face of the cross section of the blade and the line connecting the leading edge portion and the trailing edge portion is f 3; at the blade top element surface, the maximum distance between the inner side surface of the cross section of the blade and the connecting line of the front edge part and the rear edge part is f4, f3 is larger than f1, f3 is larger than f2, and f3 is larger than f4, so that the static pressure of the pressure surface of the blade can be effectively improved, the working capacity of the blade is improved, the outlet wind speed is improved, and the efficiency of the fan blade is improved.

6. The blades are sweepback, namely the blades are obliquely bent along the incoming flow direction, so that the blades can generate circumferential and axial forces and radial forces, the radial forces can effectively change the thickness of an airflow boundary layer, the airflow efficiency is improved, and the power and the noise are reduced.

7. According to the blade provided by the invention, the suction surface is provided with the concave part above the 3/4 element surface, so that the pressure surface is provided with the convex surface, and thus when airflow is about to flow out of the blade and fall off, the falling off of the airflow can be delayed, the tail airflow separation is effectively reduced, the flow efficiency is improved, and the noise is improved.

8. According to the blade provided by the invention, the top end of the front edge part of the blade is provided with the sharp corner, the radius of the sharp corner is R, R is more than or equal to 3mm and less than or equal to 6mm, and the design of the tip angle can reduce the generation of vortex and front edge part separation vortex and reduce aerodynamic noise.

9. The axial flow fan blade provided by the invention comprises a hub and a plurality of blades uniformly distributed along the circumferential direction of the hub, and can effectively improve the outlet air speed, so that the pneumatic performance of the fan blade is matched with that of a motor, and the air volume of the fan is ensured.

10. According to the axial flow fan blade provided by the invention, the diameter of the hub is D, the outer diameter of the axial flow fan blade is D, and D/D is more than or equal to 0.25 and less than or equal to 0.3, so that the air flow separation and the air flow pressure can be reasonably controlled.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

Fig. 1 is a schematic view of an axial-flow fan blade in the prior art;

FIG. 2 is a cross-sectional view of the axial flow fan blade shown in FIG. 1 at the blade root;

FIG. 3 is a cross-sectional view at the tip of the axial flow fan blade shown in FIG. 1;

fig. 4 is a front view of an axial-flow fan blade provided in an embodiment of the present invention;

FIG. 5 is a schematic structural view of a portion of the axial-flow fan blade of FIG. 4;

fig. 6 is a schematic structural diagram of an axial-flow fan blade provided in an embodiment of the present invention;

FIG. 7 is a cross-sectional view of a blade of the axial flow fan blade of FIG. 6 at the blade root element face;

FIG. 8 is a cross-sectional view of a blade of the axial flow fan blade of FIG. 6 at the 1/2 primitive face;

FIG. 9 is a cross-sectional view of a blade of the axial flow fan blade of FIG. 6 at the 3/4 primitive face;

FIG. 10 is a cross-sectional view of a blade of the axial flow fan blade of FIG. 6 at the blade tip element face;

fig. 11 is a side view of the axial flow fan blade of fig. 6.

Description of reference numerals:

1-a hub; 2-a blade; 21-front edge portion; 22-rear edge portion; 23-root of leaf; 24-leaf apex; 25-pressure surface; 26-a suction surface; 31-root element surface; 32-1/2 primitive faces; 33-3/4 primitive faces; 34-leaf top element plane.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Example 1

The present embodiment provides a blade, which may be applied in an axial flow fan, in one embodiment, as shown in fig. 4 to 11, the blade 2 includes a pressure surface, a suction surface 26, a blade root 23, a blade tip 24, a leading edge 21, and a trailing edge 22, a cylindrical surface defining the blade root 23 is a blade root primitive surface 31, the blade tip 24 is a blade tip primitive surface 34, a cylindrical surface located between the blade root primitive surface 31 and the blade tip primitive surface 34 is an 1/2 primitive surface 32, and a cylindrical surface located between the blade tip primitive surface 34 and the 1/2 primitive surface is an 3/4 primitive surface 33.

The maximum distance between the leading edge portion 21 and the trailing edge portion 22 at the root element surface 31 is l1, the maximum distance between the leading edge portion 21 and the trailing edge portion 22 at the element surface 1/2 is l2, the maximum distance between the leading edge portion 21 and the trailing edge portion 22 at the element surface 3/4 is l3, the maximum distance between the leading edge portion 21 and the trailing edge portion 22 at the element surface 3/4 is l4, and l1 < l2 < l3 < l 4.

According to the blade provided by the embodiment, the wind speed at the outlet can be effectively increased by enabling l1 to be more than l2 and more than l3 to be more than l4, the pneumatic performance of the blade 2 is matched with a motor, and the wind volume of a fan made of the blade 2 is ensured.

In one embodiment, 35mm ≦ l1 ≦ 45mm, 85mm ≦ l4 ≦ 95 mm.

In addition to the above embodiments, in one embodiment, as shown in fig. 6, above the 1/2 cell face 32, the pressure face is provided with a concave portion such that the suction face 26 includes a convex surface. The static pressure of the pressure surface of the blade 2 can be effectively improved, the acting capacity of the blade 2 is improved, the outlet air speed is further improved, and the fan blade efficiency is increased.

In addition to the above embodiments, in one embodiment, the recessed portion is recessed to the maximum extent in a region from the center line of the blade 2 to the trailing edge portion 22. The arrangement can increase the working capacity of the middle rear part of the blade 2 and further improve the pneumatic performance.

In addition to the above embodiments, in one embodiment, at the root element surface 31, an included angle between a line connecting the leading edge portion 21 and the trailing edge portion 22 and a tangent line of the leading edge portion 21 at the root element surface 31 is α 1; at the 1/2 primitive surface 32, an angle α 2 between a line connecting the leading edge portion 21 and the trailing edge portion 22 and a tangent line of the leading edge portion 21 at the 1/2 primitive surface 32; at the 3/4 cell plane 33, the line connecting the leading edge portion 21 and the trailing edge portion 22 makes an angle α 3 with the tangent line of the leading edge portion 21 at the 3/4 cell plane 33; at the blade top element surface 34, an included angle α 4 between a line connecting the leading edge portion 21 and the trailing edge portion 22 and a tangent line of the leading edge portion 21 at the blade top element surface 34; alpha 1 > alpha 2 > alpha 3 > alpha 4. The large mounting angle of the blade root 23 can effectively ensure the strength of the blade 2 without increasing much load.

In one embodiment, α 1 is 35 ° ≦ α 45 °, and α 4 is 5 ° ≦ α 4 ≦ 15 °.

As shown in fig. 7 to 10, at the root element plane 31, the maximum distance f1 between the inner side surface of the cross section of the blade and the line connecting the leading edge portion 21 and the trailing edge portion 22; a maximum distance of a line connecting an inner side surface of a cross section of the blade and the leading edge portion 21 and the trailing edge portion 22 at the 1/2 primitive surface 32 is f 2; at the 3/4 primitive plane 33, the maximum distance between the inner side surface of the cross section of the blade and the line connecting the leading edge portion 21 and the trailing edge portion 22 is f 3; at the tip element surface 34, the maximum distance between the inner side surface of the cross section of the blade and the line connecting the leading edge portion 21 and the trailing edge portion 22 is f4, f3 > f1, f3 > f2, and f3 > f 4. Specifically, the inner side of the cross section of the blade refers to a concave surface, at the root element surface 31 and at the 1/2 element surface 32, the inner side of the cross section of the blade refers to a pressure surface, at the 3/4 element surface 33 and at the top element surface 34, the inner side of the cross section of the blade refers to a suction surface when the suction surface has a recess. The design can effectively improve the static pressure of the pressure surface of the blade 2, improve the acting capacity of the blade 2, further improve the outlet wind speed and increase the fan blade efficiency.

In one embodiment, f 1-f 4, f 2-1.5 f1, and f 3-2 f 1.

On the basis of the above embodiments, in one embodiment, as shown in fig. 11, the direction of the arrow in fig. 11 is an incoming flow direction, and the blade 2 is swept backward, that is, the blade 2 is bent obliquely along the incoming flow direction, so that not only circumferential and axial forces but also radial forces can be generated by the blade, and the radial forces can effectively change the thickness of the airflow boundary layer, improve airflow efficiency, and reduce power and noise. .

In one embodiment, the blade 2 has a sweep angle θ, with 8 ° ≦ θ ≦ 15 °.

In addition to the above embodiments, in one embodiment, the suction surface 26 has a concave portion above the 3/4 cell surface 33 so that the pressure surface has a convex surface.

As shown in FIG. 5, the tip end of the leading edge portion 21 of the blade 2 has a tip angle with a radius R of 3 mm. ltoreq. R.ltoreq.6 mm. The design of the blade tip angle can reduce the generation of vortex and separation vortex of the front edge part 21, and reduce aerodynamic noise.

Example 2

The embodiment provides an axial flow fan blade, which comprises a hub 1 and a plurality of blades which are uniformly distributed along the circumferential direction of the hub 1 and provided in the embodiment 1.

Experiments prove that compared with common blades in the prior art, the axial flow fan blade provided by the embodiment has the advantages that the central wind speed of the fan blade is obviously improved by 1m/s, and the wind quantity is improved by 2m³And/min. At 1100rpm, the power of the motor is reduced by 2W, the temperature rise of the motor is reduced, and the cost is favorably controlled. The axial flow fan blade can be matched with a motor, so that the energy efficiency is improved, the cost of the motor is reduced, the humming sound during high-speed rotation can be effectively reduced, and the tone quality is improved.

In one embodiment, the diameter of the hub 1 is D, the outer diameter of the axial flow fan blade is D, and D/D is more than or equal to 0.25 and less than or equal to 0.3. The air flow separation and the air flow pressure can be reasonably controlled.

In one embodiment the number of blades 2 is 7. In other alternative embodiments, the number of blades 2 may be an odd number of 3, 5, 9, etc.

Example 3

The embodiment provides a fan, which comprises the axial flow fan blade provided in the embodiment.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.

Claims

1. A blade is characterized by comprising a pressure surface (25), a suction surface (26), a blade root (23), a blade top (24), a leading edge (21) and a trailing edge (22), wherein a cylindrical surface where the blade root (23) is located is defined as a blade root primitive surface (31), a cylindrical surface where the blade top (24) is located is a blade top primitive surface (34), a cylindrical surface between the blade root primitive surface (31) and the blade top primitive surface (34) is an 1/2 primitive surface (1/2), and a cylindrical surface between the blade top primitive surface (34) and the blade top primitive surface (32) is an 3/4 primitive surface (33);

the maximum distance between the leading edge portion (21) and the trailing edge portion (22) on the root element surface (31) is l1, the maximum distance between the leading edge portion (21) and the trailing edge portion (22) on the 1/2 element surface (32) is l2, the maximum distance between the leading edge portion (21) and the trailing edge portion (22) on the 3/4 element surface (33) is l3, the maximum distance between the leading edge portion (21) and the trailing edge portion (22) on the tip element surface (34) is l4, and l1 < l2 < l3 < l 4.

2. Blade according to claim 1, characterized in that 35mm ≦ l1 ≦ 45mm, 85mm ≦ l4 ≦ 95 mm.

3. Blade according to claim 1, characterized in that above the 1/2 elementary faces (32), the pressure face (25) is provided with a concavity so that the suction face (26) comprises a convexity.

4. A blade according to claim 3, characterised in that the recess is recessed to a maximum extent in the area between the centre line of the blade to the trailing edge (22).

5. Blade according to claim 1, characterized in that at the root element surface (31) the line connecting the leading edge portion (21) and the trailing edge portion (22) makes an angle α 1 with the tangent of the leading edge portion (21) at the root element surface (31); at the 1/2 elementary plane (32), the angle between the line connecting the leading edge portion (21) and the trailing edge portion (22) and the tangent of the leading edge portion (21) at the 1/2 elementary plane (32) is alpha 2; at the 3/4 cell plane (33), the included angle between the connecting line of the front edge part (21) and the rear edge part (22) and the tangent of the front edge part (21) at the 3/4 cell plane (33) is alpha 3; at the blade top element surface (34), an included angle between a connecting line of the front edge portion (21) and the rear edge portion (22) and a tangent line of the front edge portion (21) at the blade top element surface (34) is alpha 4; alpha 1 > alpha 2 > alpha 3 > alpha 4.

6. The blade of claim 5, wherein 35 ° ≦ α 1 ≦ 45 °, 5 ° ≦ α 4 ≦ 15 °.

7. Blade according to claim 1, characterized in that at the root element face (31) the maximum distance of the inner side face of the cross-section of the blade from the line connecting the leading edge portion (21) and the trailing edge portion (22) is f 1; at the 1/2 primitive face (32), the maximum distance between the inner side face of the cross-section of the blade and the line connecting the leading edge portion (21) and the trailing edge portion (22) is f 2; at the 3/4 primitive face (33), the maximum distance between the inner side face of the cross-section of the blade and the line connecting the leading edge portion (21) and the trailing edge portion (22) is f 3; the maximum distance between the inner side surface of the cross section of the blade and the line connecting the front edge part (21) and the rear edge part (22) at the blade top element surface (34) is f4, f3 > f1, f3 > f2, and f3 > f 4.

8. The blade of claim 7 wherein f 1-f 4, f 2-1.5 f1, and f 3-2 f 1.

9. The blade of claim 1 wherein said blade is swept back.

10. The blade of claim 9 wherein the blade has a sweep angle θ of 8 ° ≦ θ ≦ 15 °.

11. Blade according to claim 3, characterized in that above the 3/4 elementary faces (33), the suction face (26) has a concave portion, so that the pressure face (25) has a convex surface.

12. A blade according to claim 1, characterised in that the leading edge part (21) of the blade has a tip angle at its tip end, the radius of which is R, 3mm ≦ R ≦ 6 mm.

13. An axial flow fan blade, characterized by comprising a hub (1), a plurality of blades according to any one of claims 1-12 being evenly distributed along the circumference of the hub (1).

14. The axial-flow fan blade according to claim 13, wherein the diameter of the hub (1) is D, the outer diameter of the axial-flow fan blade is D, and D/D is more than or equal to 0.25 and less than or equal to 0.3.

15. The axial-flow fan blade according to claim 13, wherein the number of the blades is 7.

16. A fan comprising the axial-flow blade defined in any one of claims 13 to 15.