Flow guide ring structure, semi-open type axial flow fan and air conditioner

Abstract

The invention discloses a flow guide ring structure, a semi-open type axial flow fan and an air conditioner, the flow guide ring structure comprises a flow guide ring with an arc-shaped flow guide part and a linear flow guide part, airflow flows from the arc-shaped flow guide part to the linear flow guide part, the inner diameter of the arc-shaped flow guide part is gradually reduced from the inlet end to the outlet end, and the arc-shaped flow guide part is provided with a wavy outer edge; the wave outer edge evenly fluctuates in the radial direction of the flow guide ring to form a smooth and continuous radial fluctuation curve, and the wave outer edge evenly fluctuates in the axial direction of the flow guide ring to form a smooth and continuous axial fluctuation curve. By improving the shape of the flow guide ring, the blade tip vortex influence range, strength and blade top leakage loss of a fan system are effectively reduced, vortex noise is reduced, and the performance of the axial flow fan is optimized.

Description

Technical Field

[0001] The present invention relates to the technical field of guide rings, in particular to a guide ring structure, a semi-open axial flow fan and an air conditioner. Background Art

[0002] Axial flow fans are widely used in the field of forced convection heat exchange due to their large flow characteristics. Their basic structure includes an impeller rotating around an axis and a drive motor. During operation, the airflow direction is parallel to the main shaft. In space-constrained scenarios such as air-conditioning outdoor units, existing technologies generally adopt a semi-open axial flow fan structure. The characteristic of this configuration is that it is only equipped with a guide ring covering a local area of ​​the trailing edge of the fan blade. Although this design meets the requirements of compact equipment layout and manufacturing cost control, it is constrained by the specific structure of the air-conditioning outdoor unit. There are flow obstacles such as heat exchangers and motor brackets on the air inlet side of the fan blade, which causes the flow field in the blade tip area to be distorted, forming a high turbulence intensity flow separation area.

[0003] In this complex flow environment, the tip gap leakage effect becomes a key performance-limiting factor: a tip gap exists between the tip of the axial flow blade and the inner surface of the guide ring. This gap causes tip leakage, resulting in a decrease in fan airflow and efficiency. Simultaneously, due to the pressure difference between the pressure and suction surfaces of the blade, the fluid flowing from the outer edge of the impeller inward interacts with the main flow, generating a shear boundary layer curling, which in turn induces a tip vortex. This vortex structure dominates the flow field in the blade tip region and significantly affects fan performance and aerodynamic noise.

[0004] Although there are guide ring structures in the prior art that can reduce noise to a certain extent, such as the guide ring on the front panel of the air conditioner outdoor unit, its structural characteristics are: the bell mouth of the guide ring is in a wave shape with ups and downs or staggered heights, and the bell mouth is provided with two oppositely arranged recesses with different heights, forming an asymmetric arrangement. However, when this guide ring structure is used with a semi-open axial flow fan, the area of ​​the fan blade exposed to the outside of the guide ring is further increased, causing the side and middle partition corner areas to be biased towards the low-pressure area, and the inner side of the guide ring flow channel to be biased towards the high-pressure area, causing the vortex intensity in the side heat exchanger corner area to be further increased due to blade tip leakage; on the side of the middle partition, the airflow is sucked and utilized by the fan blade before reaching the slit area between the guide ring and the middle partition. Even if part of the airflow reaches the slit area, due to the pressure difference between the inside and outside of the guide ring, the airflow in the slit area will not only still form a vortex area and be difficult to utilize, but the asymmetric structure will also seriously damage the uniformity of the annular air intake structure.

[0005] Therefore, how to design a guide ring structure that can effectively reduce blade tip vortex noise and optimize axial fan performance is a technical problem that needs to be urgently solved in the industry. Summary of the Invention

[0006] In order to solve the defects of existing semi-open axial flow fans such as large flow loss and eddy current noise, the present invention proposes a guide ring structure, a semi-open axial flow fan and an air conditioner. By improving the shape of the guide ring, the influence range, intensity and blade tip leakage loss of the fan system are effectively reduced, the eddy current noise is reduced and the performance of the axial flow fan is optimized.

[0007] The technical solution adopted by the present invention is to design a guide ring structure, including: a guide ring having an arc-shaped guide portion and a straight guide portion, the air flow flows from the arc-shaped guide portion to the straight guide portion, the inner diameter of the arc-shaped guide portion gradually decreases from the inlet end to the outlet end, and the arc-shaped guide portion has a wavy outer edge; the wavy outer edge fluctuates uniformly in the radial direction of the guide ring to form a smooth and continuous radial fluctuation curve, and the wavy outer edge fluctuates uniformly in the axial direction of the guide ring to form a smooth and continuous axial fluctuation curve.

[0008] Furthermore, for any point P on the outer edge of the wave, the curve equation of the radial wave curve is satisfied:

[0009] R=a×sin(k×t×360)+R0

[0010]

[0011] Where R is the distance between point P and the center axis of the guide ring, in mm; a is the radial amplitude, in mm; k is the number of radial waves; t is the position coordinate of point P on the radial wave curve, t = 0 ~ 1; R0 is the radial base circle radius, R max is the maximum radius of the radial fluctuation curve, R min It is the minimum radius of the radial fluctuation curve, in mm.

[0012] Furthermore, the inner radius of the outlet end of the arc-shaped guide portion is R1. The angle formed by two adjacent wave peaks on the radial fluctuation curve and the central axis of the guide ring is α, and the value range of α is 1° to 3°.

[0013] Furthermore, for any point P on the outer edge of the wave, the curve equation of the axial wave curve is satisfied:

[0014] Z=b×sin(n×t×360+β0)+Z0

[0015]

[0016] Among them, Z is the coordinate of point P in the direction of the central axis of the guide ring, the unit is mm; b is the axial amplitude, the unit is mm; n is the number of axial waves; β0 is used to adjust the position of the axial wave trough and peak in the circumferential direction, the unit is °; t is the position coordinate of point P on the axial wave curve, t = 0 ~ 1; Z0 is the coordinate of the base circle plane where the axial base circle is located in the direction of the central axis, Z max is the maximum coordinate of point P in the direction of the central axis of the guide ring, Z min It is the minimum coordinate of point P in the direction of the center axis of the guide ring, and the unit is mm.

[0017] Furthermore, the axial length from the axial base circle to the outlet end of the guide ring is L, and the axial length from the axial base circle to the inlet end of the arc-shaped guide portion is L1. The value range of n is 2 to 12.

[0018] Furthermore, the straight guide portion is composed of a first straight portion and a second straight portion, the first straight portion is connected between the arc-shaped guide portion and the second straight portion, and the inner diameter of the second straight portion gradually increases from the inlet end to the outlet end.

[0019] Furthermore, an included angle between the second straight portion and the first straight portion is γ, and a value range of γ is 2° to 8°.

[0020] Furthermore, the inner walls of the first straight portion and the second straight portion are provided with a plurality of protrusion structures spaced apart along the circumferential direction, and the trajectory of each protrusion structure is a continuous plurality of arcs starting from the inlet end of the first straight portion and ending at the outlet end of the second straight portion.

[0021] Furthermore, the angle formed between the starting point and the end point of the protruding structure and the central axis on the outlet plane projection of the guide ring is θ, and the value range of θ is 10° to 30°.

[0022] Furthermore, the raised structure includes a plurality of raised points, and the raised points in the raised structure are sequentially spaced and distributed along the inlet end of the first straight portion to the outlet end of the second straight portion to form a plurality of continuous arcs.

[0023] Furthermore, the equivalent circle radius of the convex point is R2, and the value range of R2 is 1mm to 4mm; the maximum height of the convex point protruding from the inner wall is h, and the value range of h is 1mm to 3mm; the distance between two adjacent convex points is W,

[0024] The present invention also proposes a semi-open axial flow fan, comprising: an axial flow blade and a guide ring, wherein the guide ring is sleeved on the periphery of the axial flow blade and only covers a local area of ​​the trailing edge of the axial flow blade, and the guide ring adopts the above-mentioned guide ring structure.

[0025] The present invention also provides an air conditioner, comprising: an outdoor unit, wherein the fan of the outdoor unit adopts the above-mentioned semi-open axial flow fan.

[0026] Compared with the prior art, the present invention has at least one of the following beneficial effects:

[0027] 1. The guide ring has an arc-shaped guide part and a straight guide part. The outer edge of the arc-shaped guide part has the comprehensive characteristics of radial and axial fluctuation curves, which destroys the periodicity of local vortices at different circumferential phases and axial heights at the guide ring inlet, thereby changing the flow trajectory of the tip vortex core, effectively reducing the influence range and intensity of the tip vortex of the semi-open axial flow blade, destroying the periodicity of the circumferential vortex, and reducing vortex noise;

[0028] 2. The inner side of the linear guide has a convex structure that is obliquely distributed from the inlet end to the outlet end. The convex structure cuts off the return path of the blade tip gap, making the flow in the blade tip area more stable and uniform, thereby reducing the blade tip leakage loss, weakening the blockage effect of the overflow, and increasing the fan air volume. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention is described in detail below with reference to the embodiments and accompanying drawings, in which:

[0030] Figure 1 It is a three-dimensional schematic diagram of the axial flow fan of the present invention;

[0031] Figure 2 It is a three-dimensional schematic diagram of the guide ring structure of the present invention;

[0032] Figure 3 2. It is a schematic diagram of the radial fluctuation curve of the arc-shaped guide portion of the present invention;

[0033] Figure 4 This is a partially enlarged schematic diagram of the radial fluctuation curve of the arc-shaped guide portion of the present invention;

[0034] Figure 5 Schematic diagram of the axial fluctuation curve of the arc-shaped guide portion of the present invention;

[0035] Figure 6 This is a partially enlarged schematic diagram of the axial fluctuation curve of the arc-shaped guide portion of the present invention;

[0036] Figure 7 is a schematic diagram of the trajectory of the protruding structure of the present invention;

[0037] Figure 8 It is a partial enlarged schematic diagram of the protrusion structure of the present invention;

[0038] Figure 9 is a schematic cross-sectional view of a protrusion structure of the present invention;

[0039] Figure 10 It is a partial enlarged schematic diagram of the protrusion structure of the present invention;

[0040] 1. Guide ring; 11. Arc-shaped guide portion; 111. Wave outer edge; 111_1. Radial base circle; 111_2. Axial base circle; 12. Straight guide portion; 121. First straight portion; 122. Second straight portion; 13. Raised structure; 131. Protrusion; 2. Axial flow blade. DETAILED DESCRIPTION

[0041] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0042] like Figure 1 As shown, the guide ring structure proposed in the present invention is suitable for fans, especially semi-open axial fans. The semi-open axial fan has an axial fan blade 2 and a guide ring 1. The front side of the axial fan blade 2 is open, and the rear trailing edge area of ​​the axial fan blade 2 covers the guide ring 1. Due to the presence of external obstructions such as a heat exchanger on the air inlet side, a unique layout is formed with open circulation in the front and semi-constrained in the rear. While achieving axial compactness, it also leads to the complication of the flow in the blade tip gap area, which becomes the core area of ​​energy loss and noise generation. Based on this, the present invention improves the shape of the guide ring 1 to achieve the effect of high air volume and low noise.

[0043] like Figures 2 to 6 As shown, specifically, the guide ring structure includes: a guide ring 1 having an arcuate guide portion 11 and a straight guide portion 12. The arcuate guide portion 11 is located upstream of the straight guide portion 12. The airflow flows from the arcuate guide portion 11 to the straight guide portion 12. The inner diameter of the arcuate guide portion 11 gradually decreases from the inlet end to the outlet end, playing the role of air collection and guidance. The arcuate guide portion 11 has a wavy outer edge 111. The wavy outer edge 111 fluctuates uniformly in the radial direction of the guide ring 1 to form a smooth and continuous radial fluctuation curve. The wavy outer edge 111 fluctuates uniformly in the axial direction of the guide ring 1 to form a smooth and continuous axial fluctuation curve. The periodicity of the axial and radial waves on the outer edge of the guide ring is used to interfere with the periodicity of the blade during rotation, thereby destroying the periodicity of local vortices at different circumferential phases and axial heights at the inlet of the guide ring 1, improving the tip vortex phenomenon unique to the blade top area of ​​the axial flow blade 2, and thus reducing noise.

[0044] This design designs the outer edge of the arc-shaped guide part 11 into a special shape, changes the axial height and radial height distribution of the outer edge of the guide ring 1, and has the structural characteristics of axisymmetry and center symmetry. Compared with the traditional guide ring structure, the wave outer edge of the present invention destroys the circumferential periodicity of the complete ring, and then replaces it with the periodicity of axial waves and radial waves, without completely disrupting the uniformity of the circumferential air intake structure, avoiding the formation of a large difference in the circumferential gap between the guide ring and the blade tip of the fan, resulting in the problem of increased local eddy current turbulence and noise.

[0045] like Figure 3 、 4 As shown, in some embodiments of the present invention, for any point P on the wave outer edge 111, the curve equation of the radial wave curve is satisfied:

[0046] R=a×sin(k×t×360)+R0

[0047]

[0048] Wherein, R is the distance between point P and the central axis of the guide ring 1, in mm; a is the radial amplitude, in mm; k is the number of radial waves; t is the position coordinate of point P on the radial wave curve, t = 0 to 1, that is, point P circles 360° from the starting point (t = 0) to the end point (t = 1); R0 is the radius of the radial base circle 111_1, R max is the maximum radius of the radial fluctuation curve, R min It is the minimum radius of the radial fluctuation curve, in mm.

[0049] This design uses the curvature of the wave to trigger the periodic transition of the boundary layer, generating ordered streamwise vortices to enhance turbulent mixing, reduce the size of the separation zone, and lower the total pressure loss coefficient. The radial amplitude a and the number of radial waves k are used to coordinately control the stretching and breaking process of the tip vortex, attenuating the vortex peak and reducing the discrete noise. R0 is used to maintain the reference flow area and improve flow stability.

[0050] On this basis, the preferred solution is: the inner radius of the outlet end of the arc-shaped guide portion 11 is R1, When a is too small, the radial wave structure is not obvious, the shearing effect on the local large circumferential vortex will be reduced, the ability to break up the large vortex will be weakened, and the blockage effect and tip vortex phenomenon of the flow inside the guide ring cannot be effectively improved; when a is too large, the air collection and guidance function of the arc-shaped guide part 11 will be reduced, causing the wind volume to be greatly attenuated. When R0 is too small, the circumferential airflow cannot be effectively guided; when R0 is too large, it may interfere with the upstream heat exchanger structure, resulting in insufficient design space; in the direction of the intake projection plane, the angle formed by the two adjacent wave peaks on the radial fluctuation curve and the central axis of the guide ring 1 is α, and the value range of α is 1°~3°. When α is too small, the distance between adjacent wave peaks is small, which increases the precision requirements and manufacturing difficulty, and the number k of radial waves formed is large, which cannot effectively play the role of radial waves; when α is too large, the distance between adjacent wave peaks is large, which will lead to insufficient air collection and diversion capacity.

[0051] like Figure 4 、 5As shown, in some embodiments of the present invention, for any point P on the wave outer edge 111, the curve equation of the axial wave curve is satisfied:

[0052] Z=b×sin(n×t×360+β0)+Z0

[0053]

[0054] Among them, Z is the coordinate of point P in the direction of the central axis of the guide ring 1, the unit is mm; b is the axial amplitude, the unit is mm; n is the number of axial waves; β0 is used to adjust the position of the axial wave trough and peak in the circumferential direction, the unit is °; t is the position coordinate of point P on the axial wave curve, t = 0 ~ 1, that is, point P circles 360° from the starting point (t = 0) to the end point (t = 1); Z0 is the coordinate of the base circle plane where the axial base circle 111_2 is located in the direction of the central axis, Z max is the maximum coordinate of point P in the direction of the central axis of the guide ring 1, Z min It is the minimum coordinate of point P in the direction of the central axis of the guide ring 1, and the unit is mm.

[0055] This design uses sinusoidal wave disturbances to excite ordered directional vortex pairs, promotes the boundary layer to transition to turbulence in advance, effectively suppresses airflow separation, uses the phase angle β0 to form a matching association with the blade wake frequency, and significantly attenuates the discrete noise peak through vortex-wave destructive interference. The axial amplitude b is used to regulate the adverse pressure gradient intensity, effectively reducing the total pressure loss coefficient, and Z0 is used to maintain flow output stability.

[0056] On this basis, the preferred solution is: the axial length from the axial base circle 111_2 to the outlet end of the guide ring 1 is L, and the axial length from the axial base circle 111_2 to the outlet end of the arc-shaped guide portion 11 is L1.

[0057] When b or L1 is too small, the axial fluctuation characteristics of the wave outer edge 111 will be weakened, failing to effectively disrupt the circumferential periodicity of the flow within the guide ring 1 to prevent noise superposition. When b is too large, the axial fluctuation is too severe, failing to effectively guide the circumferential airflow, and easily causing local eddy current losses. When L1 is too large, the axial length of the straight guide portion 12 is shortened, the average tip clearance of the arc-shaped guide portion 11 increases, and leakage losses are increased. The value of n ranges from 2 to 12. When n is too large, it seriously affects the circumferential air intake uniformity of the guide ring 1, generates local eddies, and increases fan noise.

[0058] like Figure 2As shown, in some embodiments of the present invention, the straight guide portion 12 is composed of a first straight portion 121 and a second straight portion 122. The first straight portion 121 connects the curved guide portion 11 and the second straight portion 122, and the inner diameter of the second straight portion 122 gradually increases from the inlet to the outlet. This design achieves efficient airflow control through a three-stage progressive design. The curved guide portion 11 provides smooth pre-guiding at the front end, effectively suppressing the formation of separation vortices caused by the impact of the incoming flow. The first straight portion 121 serves as a flow field stabilization segment connecting the upstream and downstream, promoting a uniform flow velocity distribution to reduce turbulence intensity. The second straight portion 122 adopts a continuously expanding configuration to achieve controllable pressure diffusion, actively suppressing airflow separation during the efficient conversion of kinetic energy to static pressure.

[0059] It should be pointed out that since the inner diameter of the first straight portion 121 is unchanged and is connected between the outlet end of the arc-shaped guide portion 11 and the inlet end of the second straight portion 122, the inner radius of the outlet end of the arc-shaped guide portion 11 in the above text is R1, which is equal to the inner radius of the first straight portion 121, that is, the inner radius of the first straight portion 121 can also be selected in practical applications; the axial length from the axial base circle 111_2 to the outlet end of the arc-shaped guide portion 11 in the above text is L1, which is equal to the axial length from the axial base circle 111_2 to the inlet end of the first straight portion 121, that is, the axial length from the axial base circle 111_2 to the inlet end of the first straight portion 121 can also be selected in practical applications.

[0060] like Figure 6 As shown, on this basis, the preferred solution is: the angle formed by the second straight portion 122 and the first straight portion 121 is γ, and the value range of γ is 2°~8°. The reason is that when γ is less than 2°, there is a problem of difficulty in demolding during manufacturing, which cannot meet the manufacturing requirements. When γ is greater than 8°, the excessive diffusion angle will cause the adverse pressure gradient to exceed the critical value, resulting in a sharp increase in the boundary layer momentum thickness, inducing the airflow to separate from the wall to form a recirculation vortex area, occupying the effective flow area of ​​the flow channel, thereby significantly reducing the air volume.

[0061] like Figure 7 、 8 As shown, in a preferred embodiment of the present invention, the inner walls of the first straight portion 121 and the second straight portion 122 are provided with a plurality of circumferentially spaced protrusions 13. The trajectory of each protrusion 13 is a continuous arc, starting from the inlet end of the first straight portion 121 and ending at the outlet end of the second straight portion 122. As viewed from the outlet end of the guide ring 1, the axial flow blade 2 rotates counterclockwise, and the airflow enters the straight guide portion 12 from the arc-shaped guide portion 11. The airflow in the blade tip gap is guided and rectified by the protrusions 13, flowing from the starting point of the protrusion 13 of the first straight portion 121 to the end point of the protrusion 13 of the second straight portion 122. The protrusions 13 cut off the return flow path of the blade tip gap, reducing the intensity of the return vortex and leakage loss in the blade tip gap.

[0062] On this basis, viewed from the direction of the outlet of the guide ring 1, the angle formed by the starting point and the end point of the protruding structure 13 and the central axis on the outlet plane projection of the guide ring 1 is θ, and the value range of θ is 10° to 30°. When θ is too small, the trajectory of the protruding structure 13 is close to being parallel to the central axis, and the blade tip leakage phenomenon cannot be stably suppressed; when θ is too large, the protruding structure 13 generates a strong shear force on the airflow in the blade tip area, which is not adapted to the mainstream flow direction in the guide ring 1.

[0063] like Figures 7 to 10 As shown, in some feasible embodiments of the present invention, the raised structure 13 includes a plurality of protrusions 131. The protrusions 131 within the raised structure 13 are sequentially spaced from the inlet of the first straight portion 121 to the outlet of the second straight portion 122 to form a continuous multi-segment arc. This design utilizes each protrusion to sequentially generate a secondary flow vortex system, promoting momentum exchange between the mainstream and the boundary layer, maintaining airflow close to the wall, and utilizing the continuous arc structure to gradiently distribute vortex size along the flow direction, accelerating the breakdown of large vortices into small-scale turbulence and reducing energy dissipation losses. Furthermore, the protrusions in the multiple arc segments form chain-like reattachment points, disrupting the coherence of the separation bubble and preventing large-scale flow separation.

[0064] On this basis, the equivalent circle radius of the protrusion 131 is R2, and the value range of R2 is 1mm~4mm. The maximum height of the protrusion 131 protruding from the inner wall is h, and the value range of h is 1mm~3mm. When R2 or h is too small, the characteristics of the protrusion structure 13 are not obvious, and it is difficult to manufacture and cannot effectively guide and rectify the flow; when h is too large, the blade tip clearance is too small, and the deformation of the blade during the rotation of the wind blade may cause dynamic and static interference problems; when R2 is too large, the number of protrusion structures 13 distributed will be reduced, and a stable boundary layer flow cannot be formed between adjacent protrusion structures 13, thereby cutting off the leakage in the blade tip clearance area. The spacing between two adjacent protrusions 131 is W, When W is too small, the nearly gapless distribution of the convex points 131 cannot effectively break up the local large vortex structure into a small vortex structure, and thus the ability to reduce drag and noise will be weakened; when W is too large, a relatively stable flow cannot be formed between adjacent convex points 131, and leakage loss cannot be effectively reduced.

[0065] like Figure 1As shown, the present invention also proposes a semi-open axial flow fan, comprising: an axial flow blade 2 and a guide ring 1, wherein the guide ring 1 is sleeved on the periphery of the axial flow blade 2 and only covers a local area of ​​the trailing edge of the axial flow blade 2, and the guide ring 1 adopts the above-mentioned guide ring structure. The wave outer edge 111 of the guide ring structure has the comprehensive characteristics of the radial wave curve and the axial wave curve, which destroys the periodicity of the local vortex at different circumferential phases and axial heights on the inlet side of the guide ring 1, thereby changing the flow trajectory of the tip vortex core, reducing the influence range and intensity of the tip vortex of the semi-open axial flow blade, and reducing the vortex noise; the inner side of the straight guide portion 12 has a protruding structure 13 obliquely distributed from the inlet to the outlet, which cuts off the return path of the blade tip gap, making the flow in the blade tip area more stable and uniform, thereby reducing the blade tip leakage loss, weakening the blockage effect of the overflow, and increasing the fan air volume. Compared with the traditional guide ring, when the guide ring structure of the preferred embodiment of the present invention is applied to a semi-open axial flow fan, under the same test conditions and the same speed conditions, the air volume of the whole machine is increased by about 2%; under the same test conditions and the same air volume conditions, the noise sound pressure level is reduced by about 0.7dB(A).

[0066] The present invention also provides an air conditioner, comprising: an outdoor unit, wherein the fan of the outdoor unit adopts the above-mentioned semi-open axial flow fan, and the outdoor unit has low noise and good performance during operation.

[0067] It should be noted that the terms used above are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. When the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof. The order of execution of actions, steps, etc. in the devices and methods shown in the specification and the drawings can be implemented in any order as long as there is no special explicit limitation on the order and as long as the output of the previous processing is not used in the subsequent processing. Similar sequential terms used for the convenience of description do not mean that they must be implemented in such an order.

[0068] Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail, but, where appropriate, such techniques, methods, and apparatus should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following figures, and therefore, once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

[0069] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. Guide ring structure, including: A guide ring having an arcuate guide portion and a straight guide portion, wherein the airflow flows from the arcuate guide portion to the straight guide portion, the inner diameter of the arcuate guide portion gradually decreases from the inlet end to the outlet end, and the arcuate guide portion has a wavy outer edge; It is characterized in that the outer edge of the wave fluctuates evenly in the radial direction of the guide ring to form a smooth and continuous radial fluctuation curve, and the outer edge of the wave fluctuates evenly in the axial direction of the guide ring to form a smooth and continuous axial fluctuation curve.

2. The guide ring structure according to claim 1, characterized in that: For any point P on the outer edge of the wave, the curve equation of the radial wave curve is satisfied: R=a×sin(k×t×360)+R0 Wherein, R is the distance between point P and the center axis of the guide ring, in mm; a is the radial amplitude, in mm; k is the number of radial waves; t is the position coordinate of point P on the radial wave curve, t = 0 to 1; R0 is the radial base circle radius, R max is the maximum radius of the radial fluctuation curve, R min is the minimum radius of the radial fluctuation curve, in mm.

3. The guide ring structure according to claim 2, characterized in that: The inner radius of the outlet end of the arc-shaped guide portion is R1. The angle formed between two adjacent wave peaks on the radial fluctuation curve and the central axis of the guide ring is α, and the value range of α is 1° to 3°.

4. The guide ring structure according to claim 1, characterized in that: For any point P on the outer edge of the wave, the curve equation of the axial wave curve is satisfied: Z=b×sin(n×t×360+β0)+Z0 Among them, Z is the coordinate of point P in the direction of the central axis of the guide ring, the unit is mm; b is the axial amplitude, the unit is mm; n is the number of axial waves; β0 is used to adjust the position of the axial wave trough and peak in the circumferential direction, the unit is °; t is the position coordinate of point P on the axial wave curve, t = 0 ~ 1; Z0 is the coordinate of the base circle plane where the axial base circle is located in the direction of the central axis, Z max is the maximum coordinate of point P in the direction of the central axis of the guide ring, Z min is the minimum coordinate of point P in the direction of the central axis of the guide ring, in mm.

5. The guide ring structure according to claim 4, characterized in that: The axial length from the axial base circle to the outlet end of the guide ring is L, and the axial length from the axial base circle to the outlet end of the arc-shaped guide portion is L1. The value range of n is 2 to 12.

6. The guide ring structure according to claim 1, characterized in that: The straight guide portion is composed of a first straight portion and a second straight portion, the first straight portion is connected between the arc-shaped guide portion and the second straight portion, and the inner diameter of the second straight portion gradually increases from the inlet end to the outlet end.

7. The guide ring structure according to claim 6, characterized in that: An included angle between the second straight portion and the first straight portion is γ, and a value range of γ is 2° to 8°.

8. The guide ring structure according to claim 6, characterized in that: The inner walls of the first straight portion and the second straight portion are provided with a plurality of protrusion structures spaced apart along the circumferential direction, and the trajectory of each protrusion structure is a continuous plurality of arcs starting from the inlet end of the first straight portion and ending at the outlet end of the second straight portion.

9. The guide ring structure according to claim 8, characterized in that: The angle formed by the starting point and the end point of the protruding structure and the central axis on the outlet plane projection of the guide ring is θ, and the value range of θ is 10° to 30°.

10. The guide ring structure according to claim 8, characterized in that: The convex structure includes a plurality of convex points, and the convex points in the convex structure are sequentially spaced from the inlet end of the first straight portion to the outlet end of the second straight portion to form the continuous multiple arcs.

11. The guide ring structure according to claim 10, characterized in that: The equivalent circle radius of the convex point is R2, and the value range of R2 is 1mm~4mm; the maximum height of the convex point protruding from the inner wall is h, and the value range of h is 1mm~3mm; the distance between two adjacent convex points is W, 12. Semi-open axial flow fan, including: An axial flow fan blade and a guide ring, wherein the guide ring is sleeved on the periphery of the axial flow fan blade and only covers a local area of ​​the trailing edge of the axial flow fan blade, characterized in that the guide ring adopts the guide ring structure according to any one of claims 1 to 11.

13. Air conditioners, including: The outdoor unit is characterized in that the fan of the outdoor unit adopts the semi-open axial flow fan described in claim 12.

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