WO2020125128A1

WO2020125128A1 - Axial flow fan blade, ventilation device and air conditioner

Info

Publication number: WO2020125128A1
Application number: PCT/CN2019/109186
Authority: WO
Inventors: 刘中杰; 曹锋; 和浩浩; 邹建煌
Original assignee: 珠海格力电器股份有限公司
Priority date: 2018-12-19
Filing date: 2019-09-29
Publication date: 2020-06-25
Also published as: CN109538532A

Abstract

Provided are an axial flow fan blade, a ventilation device and an air conditioner. The axial flow fan blade comprises a hub (5) and a plurality of blades (4), two surfaces of each blade (4) are respectively a pressure surface (3) on the air outlet side and a suction surface (1) on the air inlet side, the radial outward edge portion of each blade (4) is a blade tip, the blade tip of each blade is provided with a first edge (21) and a second edge (22), wherein the first edge (21) is bent and extends towards the suction surface, and the second edge (22) is bent and extends towards the pressure surface. The axial flow fan blade can improve working capability of the blades (4), control the blade tip leakage vortex of the blades (4), and reduce the noise of the fan blade.

Description

Axial fan, ventilation device and air conditioner

This application requires the priority of the patent application filed with the State Intellectual Property Office of China on December 19, 2018, with the application number 201811556731.9 and the invention titled "Axial Fan, Ventilation Device, and Air Conditioner".

Technical field

The present application relates to the technical field of impeller machinery, in particular to an axial fan, a ventilator, and an air conditioner.

Background technique

In order to realize the air circulation flow, various fan blades are usually used in the ventilation device. The basic structure of the general fan blade includes a hub as a rotating shaft and a plurality of blades arranged radially on the outer periphery of the center. The leading edge of the blade flows in and blows out from the trailing edge portion of the blade after the blade is boosted, thereby forming a pressure surface and a suction surface.

During the operation of the existing axial fan blades, a low-pressure region, that is, a vortex, is often generated in the middle part of the blade tip of the suction surface. This vortex is mainly caused by the flow of air flowing through the high-pressure region of the pressure surface of the blade to the low-pressure region of the suction surface. As a result, this phenomenon is called "leakage". In addition, the suction of the blades will cause boundary layer separation near the front edge, resulting in eddy currents. In short, the above two conditions will cause the vortex noise of the fan blade, which in turn causes the total value of the fan noise to increase, which affects the overall performance of the air conditioner.

In order to reduce the blade tip vortex, in the prior art, the axial flow blade tip is designed to be bent or folded in the direction of the pressure surface toward the suction surface, as shown in FIGS. 1 to 6, and the detailed bending diagram is shown in FIGS. 7 to Figure 8, detailed diagram of hemming is shown in Figure 9 to Figure 10. The design intent is to control the diffusion of the blade tip vortex by reducing the pressure difference between the suction surface and the pressure surface at the blade tip to avoid secondary flow losses. However, while reducing the pressure difference on the suction pressure surface, it also caused a decrease in the fan blade's functional capacity, resulting in a decrease in the amount of wind generated by the fan blade.

In the existing design, when the axial flow vane rotates, 2 to 10 wind vane blades 4 are uniformly distributed or unevenly arranged on the outer periphery of the hub 5 to perform work on the air to generate air volume. At this time, the suction surface 1 of each vane blade 4 is the windward surface, so the pressure distribution on the surface of the suction surface 1 is negative; and the pressure surface 3 corresponding to the reverse side of the blade 4 is on the leeward surface, and its surface pressure distribution is Positive value. Therefore, there is a significant pressure difference at the tip 2 of the blade at a position at the boundary between the two, causing the airflow to naturally leak from the pressure surface 3 through the blade tip 2 to the suction surface 1. The greater the pressure difference, the greater the power of the leaking airflow.

When designing the blade tip 2 of the axial flow blade in the prior art, the hemming structure shown in FIGS. 1 to 10 is adopted, which is “L” type (L lower end is the blade tip), or the bending structure is “J” type (The lower end of J is the blade tip) It is used to alleviate the pressure difference between the pressure surface and the suction surface, so as to avoid the leakage of the airflow and the influence of the leakage airflow on the mainstream flow. The key parameters of the hemming structure include the angle a1 or a2 of the hemming edge, the position of the hemming edge D2, and the range of the hemming edge at the tip of the blade. The key parameters of the hemming structure include the bending radius R1 or R2, and the bending position D2. Bending is within the range of the blade tip. Obviously, after adopting such a structure that the pressure faces the suction surface with a single hem or a bend, the working force of the blade 4 near the blade tip will be reduced, that is, the pressure on the pressure surface near the blade tip will decrease and the pressure on the suction surface will increase, resulting in the blade 4 The functional capacity here is reduced, and the air volume generated by the axial flow blades is reduced. In particular, the axial fan blades for air conditioning, the main work area of the blade 4 lies in the trailing edge of the blade tip.

Summary of the invention

In order to solve the problems in the prior art, the main purpose of the present application is to provide an axial fan blade, a ventilator, and an air conditioner, so as to effectively control the diffusion of the blade tip vortex.

A further object of the present application is to provide an axial fan blade with two bending or flanging structures at the same time, which can control the degree of turbulence of the leakage airflow at the tip of the blade and reduce the turbulence generated by the axial fan blade here noise.

At least one embodiment of the present application provides an axial-flow blade, including a hub and a plurality of blades, and the two surfaces of each blade are a pressure surface on the air outlet side and a suction surface on the air inlet side, respectively. The radially outward edge portion is the blade tip, and the blade tip of each blade is provided with a first edge and a second edge, the first edge is bent and extends toward the suction surface, and the second edge is oriented The pressure surface is bent and extended.

According to an embodiment of the present application, the first side and the second side are a bent structure or a folded structure relative to the blade body.

According to an embodiment of the present application, the maximum outer diameter of the first side is equal to the maximum outer diameter of the second side.

According to an embodiment of the present application, the maximum outer diameter of the first side is smaller than the maximum outer diameter of the second side.

According to an embodiment of the present application, the first side and the second side are disposed within the entire length of the blade tip.

According to an embodiment of the present application, the first side and the second side are disposed in a partial range of the blade tip.

According to an embodiment of the present application, the maximum outer diameter of the first side is greater than the maximum outer diameter of the second side.

According to an embodiment of the present application, the first side is an arc bend with a first radius, the second side is an arc bend with a second radius, the first radius is smaller than the second radius.

According to an embodiment of the present application, the first side is a flange having a first angle with the blade body, and the second side is a flange with a second angle with the blade body, the first An angle is smaller than the second angle.

According to an embodiment of the present application, the first side is an arc-shaped bend, and the second side is a folded edge having a second angle with the blade body.

According to an embodiment of the present application, the setting range of the first side and the second side accounts for 0.4-0.6 of the total length of the blade tip.

According to an embodiment of the present application, it can also be considered that a ventilation device is provided, which includes an axial fan blade, and the axial fan blade is the aforementioned axial fan blade.

According to an embodiment of the present application, it can also be considered that an air conditioner is provided, which includes an axial fan blade, and the axial fan blade is the aforementioned axial fan blade.

The beneficial effect obtained by adopting the above optional technical solution is that the structure of the blade tip is changed from the original two-dimensional edge structure to a three-dimensional space interval. This structure can play the role of buffering pressure, alleviating airflow leakage, and controlling the flow, so as to improve the working capacity of the axial fan blade, increase the air volume, and reduce the noise by controlling the blade tip leakage vortex.

Compared with the existing fan blades, the fan blades of the present application enhance the function of the blades, realize the control of the blade tip leakage vortex, and reduce the blade noise.

BRIEF DESCRIPTION

Figure 1: Schematic diagram of the front view of the existing folding axial flow fan blade;

Figure 2: Schematic diagram of the current side of the folded flange axial flow fan blade;

Figure 3: Schematic diagram of the top view of the existing folding axial flow fan blades;

Figure 4: Schematic diagram of the front view of the existing bending axial fan;

Figure 5: Schematic diagram of the side view of the existing bending axial fan blade;

Figure 6: Schematic diagram of the top structure of the existing bending axial fan;

Figure 7: The detailed structure diagram of the existing folded edge axial flow fan blade 2

Figure 8: The detailed structural schematic diagram of the existing folding edge axial flow fan blade 3;

Figure 9: Existing bending axial flow vane Figure 5 Detailed structural diagram of the bending structure;

Figure 10: The detailed schematic diagram of the bending structure of the existing bending axial flow blade 6;

Figure 11: A schematic diagram of the front view of the first embodiment of the present application;

Figure 12: Schematic diagram of a side view of an embodiment of the present application;

Figure 13: Schematic diagram of the top view of the first embodiment of the present application;

Figure 14: A detailed schematic diagram of the tip bending of an embodiment of the present application;

Figure 15: A schematic diagram of the front view of the second embodiment of the present application;

Figure 16: Schematic diagram of a side view of an embodiment of the present application;

Figure 17: Schematic diagram of the top view of the second embodiment of the present application;

Figure 18: Detailed structural diagram of the bending structure of the second embodiment of the present application;

FIG. 19: Schematic diagram of the structure of the two-blade crimping or bending area according to the embodiment of the present application;

Figure 20: Detailed schematic diagram of the hemming structure of the third embodiment of the present application;

Figure 21: Comparison of relative velocity distribution at the downstream of the blade near the tip of the blade;

Figure 22: Comparison of the velocity distribution of the wind blade near the blade tip.

1. Suction surface; 2. Blade tip; 3. Pressure surface; 4. Blade; 5. Wheel hub;

a1, a2, a3-angle of folding edge;

R1, R2, R3——Bending radius in different places;

D1, D2, D3-the diameter of different places;

b1, b2-different angles of the center of the circle.

detailed description

To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments It is a part of the embodiments of this application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without making creative efforts fall within the protection scope of the present application.

An embodiment of the present application provides an axial fan blade, which mainly includes a hub 5 and a plurality of blades 4, and the two surfaces of each blade 4 are a pressure surface 3 on the outlet side and a suction surface 1 on the inlet side, respectively. The radially outward edge portion of the blade 4 is a blade tip 2. Each blade tip 2 of the blade 4 is provided with a first side 21 and a second side 22. The first side 21 faces the suction surface 1 Bending and extending, the second side 22 is bent and extending toward the pressure surface 3.

There is a certain gap between the blade tip of the existing wind blade and the surrounding static components. The air flow here is relatively turbulent. It is the main area of secondary flow, leakage, and return flow, and the main source of noise. Therefore, the design of the structure here has a significant impact on the performance of the fan blades. Existing design of the blade tip of the axial flow blade, whether it is a "L" shape with a folded structure or a "J" shape with a curved structure, the outermost blade tip is a single two Dimensional curve, the airflow is easy to produce secondary flow, leakage, backflow and other turbulent flow through the gap formed with the surrounding static components.

The axial fan blade structure provided by the embodiment of the present application has bends at the blade tip of the blade 4 toward the pressure surface 3 and the suction surface 1, respectively, so that it can be formed

Type, or the folded-edge structure "Y" type, the structure of the blade tip and the surrounding static parts form an area with a substantially triangular cross-section, and the gap is changed from the original two-dimensional edge structure to a three-dimensional space interval. By adjusting a1/a3, R1/R3, b1/b2 and other parameters, the shape of the three-dimensional space can be changed, which can play a role in buffering pressure, alleviating airflow leakage, and controlling the flow, which can improve the working capacity and increase of the axial fan blade. Air volume and reduce noise by controlling blade tip leakage vortex.

In the following, in conjunction with specific embodiments of the present application, an exemplary description is as follows:

a1, a2, a3 folding angle;

Bending radius at different places of R1, R2, R3;

D1, D2, D3 different diameters;

b1, b2 different center angles.

Definition a1: In Figure 7, the fold line is tangent to both sides along the polyline, and the angle between the two tangents is a1; Similarly, definition a2: In Figure 8, the fold line is made tangent to the sides along the polyline, and the two tangents The included angle is a2; Definition a3: In Figure 20, the three crimped surfaces along the fold line to the fold line are tangent, the angle between the tangent of the blade near the inner side and the tangent to the first crimped surface is a1, and the blade is near the inner side The angle between the tangent and the tangent of the second hemming surface is a3.

Definition R1, R2, R3 are similar to a1, a2, a3, here is different from fold line as tangent, but tangent circle at the fold line, the definition of tangent radius is named R1, R2, R3.

D1 is the center of the rotation axis, the axis of rotation is normal, and the maximum diameter is tangent to the outer diameter of the fan blade, that is, the maximum outer diameter of the suction surface bending or hemming structure, D2 is the center of rotation through the rotation axis 、The rotation axis is a normal line to draw a circle. The line diameter is D2 when the line is suddenly changed by the hemming structure fold line or the bending structure curvature; D3 is the circle drawn by the rotation axis as the center and the rotation axis as the normal line. The pressure surface is bent or The outer diameter of the hemming structure.

b1——the outermost circle point of the leading edge of the blade, the starting point of the bend or edge along the direction of airflow, the angle between the two points and the center of the circle; b2——the outermost circle point of the trailing edge of the blade, bend or The starting point of the folding edge along the direction of airflow, the angle between the two points and the center of the circle.

Example one

11 is a schematic view of a front view of an embodiment of the present application, FIG. 12 is a schematic view of a side view of an embodiment of the present application, FIG. 13 is a schematic structural view of a top view of an embodiment of the present application, and FIG. 14 is a bent top of an embodiment of the present application Detailed structural diagram.

As shown in the figure, the entire range of the blade tip 2 of the blade 4 is set (the entire length of the blade tip refers to the entire length of the entire blade tip from the leading edge of the intake to the trailing edge of the outlet). , That is, the first side 21 and the second side 22, the blade tip 2 as a whole

type(

The upper end is the blade tip 2), or the structure of the hemming is in the shape of "Y" (the upper end of Y is the blade tip 2). The first side 21 is bent toward the suction surface 1 to one side to produce a structure with a bending radius of R1, thereby ensuring that the positive pressure area of the pressure surface is not affected, that is, the function of the wind blade is ensured. The second side 22 also bends toward the pressure surface 3 to produce a structure with a bending radius of R3, thereby ensuring the pressure increase of the pressure surface 3 near the blade tip and reducing the pressure between the pressure surface 3 and the suction surface 1 If the difference is too large, it may cause air leakage. In this embodiment, the structure of the blade tip 2 is changed from the original two-dimensional edge structure to a three-dimensional space interval. This structure can play the role of buffering pressure, alleviating airflow leakage, and controlling the flow, so as to improve the working capacity of the axial flow blade, increase the air volume, and reduce the noise by controlling the blade tip leakage vortex.

It should be understood by those skilled in the art that the embodiment in which the double-sided bending is provided in a full range is more suitable for the embodiment of a fan blade with a low wind speed and a large blade surface.

In this embodiment, the first side 21 is an arc bend with a first radius R1, the second side 22 is an arc bend with a second radius R3, and the first radius R1 is greater than the second Radius R3.

Example 2

15 is a schematic view of the front view of the second embodiment of the present application, FIG. 16 is a schematic view of the side view of the second embodiment of the present application, FIG. 17 is a schematic top view of the second embodiment of the present application, and FIG. 18 is a detailed view of the bending structure of the second embodiment of the present application A structural schematic diagram, and FIG. 19 is a schematic structural diagram of a two-blade crimping or bending region according to an embodiment of the present application.

As shown in the figure, in the partial range of the blade tip 2 of the blade 4, bending to the pressure surface 3 and the suction surface 1, respectively, is provided. The partial range of the blade tip (with respect to the "full length range of the blade tip", only one end of the blade tip There is a first side and a second side), that is, from b1 to the outermost circle point of the leading edge of the blade 4 in FIG. 19, the starting point of the bend or edge along the direction of airflow, the angle between the two points and the center of the circle; b2——The starting point of the outermost circle point, bend or edge of the trailing edge of the blade 4 along the direction of airflow, and the angle between the two points and the center of the circle. The full range of the blade tip (that is, the full length of the blade tip) is a bent or folded structure, and b1=0; if it is a partial range of the blade tip, b1/(b1+b2) belongs to (0,1). In a specific embodiment, it is selected that b1/(b1+b2) is in the range of (0.4 to 0.6), that is, matching with surrounding stationary components within this range has better technical advantages. It should be understood by those skilled in the art that the embodiment in which the double-sided bending is provided in a local range is more suitable for the embodiment of a fan blade with a small leaf surface at a higher wind speed. The blade is divided into multiple blade segments radially from inside to outside. The tip of the blade is the blade segment near the outermost edge and the tip of the blade, and the full length of the blade tip is the entire part of the blade tip from the leading edge side of the intake to the trailing edge side of the outlet length.

This application adopts the structure of bending or flanging on both sides, which may be the same outer diameter on both sides, or may be unequal outer diameter. That is, D1 in FIG. 18 is the outermost diameter of the fan blade, that is, the outermost diameter of the bending or flanging structure of the pressure surface 3, and D3 is the outermost diameter of the bending or flanging structure of the suction surface 1, where D1 is selected to be greater than Or equal to D3. Thereby, the amount of air leakage from the pressure surface 3 to the suction surface 1 side is reduced, that is, the air leakage in the direction opposite to the air flow is reduced.

That is, the first side 21 and the second side 22, and the blade tip 2 as a whole

type(

The upper end is the blade tip 2), or the structure of the hemming is in the shape of "Y" (the upper end of Y is the blade tip 2). The first side 21 is bent toward the suction surface 1 to one side to produce a structure with a bending radius of R1, thereby ensuring that the positive pressure area of the pressure surface is not affected, that is, the function of the wind blade is ensured. The second side 22 also bends toward the pressure surface 3 to produce a structure with a bending radius of R3, thereby ensuring the pressure increase of the pressure surface 3 near the blade tip and reducing the pressure between the pressure surface 3 and the suction surface 1 If the difference is too large, it may cause air leakage. In this embodiment, the first side 21 is an arc bend with a first radius R1, the second side 22 is an arc bend with a second radius R3, and the first radius R1 is smaller than the second Radius R3.

In this embodiment, the structure of the blade tip 2 is changed from the original two-dimensional edge structure to a three-dimensional space interval. This structure can play the role of buffering pressure, alleviating airflow leakage, and controlling the flow, so as to improve the working capacity of the axial fan blade, increase the air volume, and reduce the noise by controlling the blade tip leakage vortex.

Example Three

FIG. 20 is a detailed schematic diagram of the hemming structure of Embodiment 3 of the present application. As shown in the figure, the first side 21 and the second side 22 are folded edges, wherein the angle between the first side 21 and the blade 4 is a1, and the angle between the second side 22 and the blade 4 is a3, the relationship between the two A1≤a3, or R1≤R3. The bending or hemming structure toward the pressure surface can even be approximated as a straight plate "y" type (the upper end of y is the blade tip), that is, R3 is infinity or a3=180°.

The first group of comparative experiments

In addition, the applicant conducted a comparative test using the existing axial fan shown in FIGS. 1 to 10 and the axial fan shown in Example 1 of the present application. The structure of the comparative experiment is shown in Table 1.

Table 1. Comparison of data from simulation calculation results

结构structure	仿真计算流量m ³/h Simulation calculation flow m ³ /h
现有轴流风叶Existing axial fan	0.67490.6749
实施例一Example one	0.68290.6829

As shown in the comparison diagram in FIG. 21, the relative velocity distribution at the position downstream of the blade near the blade tip is shown. Small fluctuations in the relative speed represent relatively low noise. Therefore, the structure of the first embodiment of the present application is similar to the existing blade structure. Has an advantage.

The first group of comparative experiments

On the other hand, the applicant conducted a comparative test using the existing axial fan blades shown in FIGS. 1 to 10 and the axial fan blades shown in Example 2 of the present application. The structure of the comparative experiment is shown in Table 2.

Comparing the data of simulation calculation results with or without patent structure, the flow generated by the fan blade with patent structure is slightly larger.

结构structure	仿真计算流量m ³/h Simulation calculation flow m ³ /h
无专利结构风叶Patent-free structure	0.72740.7274
带专利结构风叶Blade with patent structure	0.75150.7515

Table 2: Comparison table of blade simulation calculation results with or without patent structure

Figure 22 shows the velocity distribution of the wind blade near the blade tip. Figure A shows the performance of the existing blade structure. There are two large vortices in the upstream and downstream of the blade tip. Figure B shows the performance of the blade of the structure of the embodiment of this application. The vortexes on the upstream and downstream of the blade tip have been suppressed to some extent, and part of the turbulent flow is controlled in the space formed by the stationary area around the blade tip and the wind blade.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still The technical solutions described in the foregoing embodiments are modified, or some of the technical features are equivalently replaced; and these modifications or replacements do not deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

An axial-flow wind blade, including a hub (5) and a plurality of blades (4), two surfaces of each blade (4) are a pressure surface (3) on the air outlet side and a suction surface (1) on the air inlet side The radial outward edge of each blade (4) is the blade tip, which is characterized by:

A first side (21) and a second side (22) are provided at the tip of each blade (4), the first side (21) is bent and extends toward the suction surface (1), and the first The two sides (22) bend and extend toward the pressure surface (3).
The axial-flow blade according to claim 1, wherein the first side (21) and the second side (22) are a bent structure or a folded structure relative to the main body of the blade (4).
The axial flow vane according to claim 1, characterized in that the maximum outer diameter of the first side (21) is equal to the maximum outer diameter of the second side (22).
The axial flow vane according to claim 1, wherein the maximum outer diameter of the first side (21) is greater than the maximum outer diameter of the second side (22).
The axial-flow blade according to claim 1, characterized in that the first side (21) and the second side (22) are provided over the entire length of the blade tip.
The axial-flow blade according to claim 1, characterized in that the first side (21) and the second side (22) are arranged in a partial range of the blade tip.
The axial-flow blade according to claim 1, wherein the first side (21) and the second side (22) are arranged in a range of 0.4 to 0.6 of the total length of the blade tip.
The axial flow vane according to claim 1, wherein the maximum outer diameter of the first side (21) is smaller than the maximum outer diameter of the second side (22).
The axial flow blade according to claim 1, characterized in that the first side (21) is an arc-shaped bend with a first radius, and the second side (22) is an arc with a second radius Shaped bend.
The axial flow vane according to claim 9, wherein the first radius is smaller than the second radius.
The axial-flow blade according to claim 1, characterized in that the first side (21) is a folded edge with a first included angle of the blade (4) body, and the second side (22) is A flange with a second angle to the main body of the blade (4).
The axial flow vane according to claim 11, wherein the first included angle is smaller than the second included angle.
The axial flow blade according to claim 1, characterized in that the first side (21) is curved and the second side (22) has a second position with the main body of the blade (4) Angled hem.
A ventilation device includes an axial fan blade, wherein the axial fan blade is the axial fan blade according to any one of claims 1 to 13.
An air conditioner includes an axial fan blade, wherein the axial fan blade is the axial fan blade according to any one of claims 1 to 13.