Sealing structure and compressor with same

Abstract

The invention provides a sealing structure and a compressor with the sealing structure, the sealing structure comprises a rotor and a static part sleeving the radial outer side of the rotor, a sealing unit is formed between the rotor and the static part, and the sealing unit comprises a wedge-shaped dynamic pressure sealing part and a fluid diffusion sealing part; the through-flow area of an inlet of a wedge-shaped flow channel of the wedge-shaped dynamic pressure sealing part is larger than that of an outlet of the wedge-shaped flow channel, an inlet of a diffusion ring cavity of the fluid diffusion sealing part communicates with the outlet of the wedge-shaped flow channel, and the outlet and the inlet of the diffusion ring cavity are arranged in a staggered mode on the axial projection of the rotor. An inlet of the wedge-shaped flow channel is communicated with the high-pressure area, and an outlet of the diffusion ring cavity is communicated with the low-pressure area. Hard contact abrasion of the rotor and the static part is avoided, the service life of the sealing structure is prolonged, meanwhile, energy of pressure fluid is further weakened through the turbulence effect generated by the fluid diffusion sealing part, and therefore the purpose of preventing gas leakage is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of air conditioning, and particularly relates to a sealing structure and a compressor having the same. Background Art

[0002] As a typical non-contact sealing structure, the working principle of the labyrinth seal is to set a series of comb-like raised structures between the rotating part and the stationary part to form a fluid damping effect, thereby effectively suppressing the leakage of gas or liquid. Its structure is usually composed of multiple combs, and these combs are arranged at intervals to form a structure similar to a comb, hence the name. In a centrifugal compressor, the labyrinth seal is generally applied to the impeller outlet or the inter-stage sealing part, mainly used to prevent the compressed gas from leaking from the high-pressure area to the low-pressure area. When the compressor operates, the high-pressure gas tries to leak through the gaps between the combs. However, due to the existence of the comb structure, the gas flow path is divided into multiple narrow channels. When the gas flows in these narrow channels, it is jointly affected by the hydrodynamic pressure effect and the frictional resistance, resulting in an increase in the pressure drop, thereby significantly reducing the leakage amount.

[0003] While the traditional labyrinth seal structure exerts its advantages, it also has some significant limitations. For example, the traditional labyrinth seal is based on the labyrinth effect of a fixed gap for sealing. However, during the operation of a high-speed centrifuge, the thermal expansion or vibration of the rotor may cause the gap to change, thereby triggering leakage or hard contact wear problems. In addition, the single wedge structure has insufficient hydrodynamic pressure effect during the low-speed or start-stop stage, poor static sealing performance, and is prone to sudden leakage. At the same time, the risk of hard contact between the tooth tip and the rotor is relatively high, and the gap expands after long-term operation, ultimately leading to seal failure. Summary of the Invention

[0004] Therefore, the present invention provides a sealing structure and a compressor having the same, which can overcome the technical problems that in the related art, when the sealing structure adopts a single labyrinth comb seal, the thermal expansion or vibration of the rotor during the operation of a high-speed centrifuge may cause the gap to change, easily triggering leakage or hard contact wear problems, while adopting a single wedge structure has insufficient hydrodynamic pressure effect during the low-speed or start-stop stage, poor static sealing performance, and is prone to sudden leakage.

[0005] To solve the above problems, the present invention provides a sealing structure, including a rotor and a stationary member sleeved on the radial outer side of the rotor. A sealing unit is formed between the rotor and the stationary member. The sealing unit includes a wedge-shaped hydrodynamic sealing portion and a fluid diffusion sealing portion. The flow-through area of the inlet of the wedge-shaped flow channel of the wedge-shaped hydrodynamic sealing portion is larger than that of the outlet of the wedge-shaped flow channel. The inlet of the diffusion ring cavity of the fluid diffusion sealing portion is communicated with the outlet of the wedge-shaped flow channel, and the outlet and the inlet of the diffusion ring cavity are arranged in a staggered manner in the axial projection of the rotor. The inlet of the wedge-shaped flow channel is communicated with the high-pressure area, and the outlet of the diffusion ring cavity is communicated with the low-pressure area.

[0006] In some embodiments, the sealing unit further includes a rectifying ring channel communicating the outlet of the wedge-shaped flow channel and the inlet of the diffusion ring cavity. The rectifying ring channel is used to introduce the fluid flowing out of the outlet of the wedge-shaped flow channel into the diffusion ring cavity in a direction tangential to the inlet of the diffusion ring cavity.

[0007] In some embodiments, the wedge-shaped flow channel is jointly formed by a first cylindrical surface on the outer wall surface of the rotor and a first conical surface on the inner wall surface of the stationary member. In the projection of any axial section of the rotor, the inclination angle of the first conical surface is 2° - 5°.

[0008] In some embodiments, the rectifying ring channel is jointly formed by a second conical surface on the outer wall surface of the rotor and a third conical surface on the inner wall surface of the stationary member. The inclination angles of the second conical surface and the third conical surface are equal, and the second conical surface gets closer to the rotor along the direction away from the wedge-shaped flow channel.

[0009] In some embodiments, in the projection of any axial section of the rotor, the inclination angle of the second conical surface is 10° - 20°; and / or, the flow-through area of the rectifying ring channel is equal to that of the outlet of the wedge-shaped flow channel.

[0010] In some embodiments, the diffusion ring cavity includes an arc surface formed on the outer wall surface of the rotor. The arc surface is tangentially connected to the second conical surface. The center of the arc surface is on the side away from the rotor, and the central angle of the arc surface is 90° - 180°.

[0011] In some embodiments, there are multiple groups of the sealing units between the rotor and the stationary member. Each group of the sealing units is arranged in sequence along the axial direction of the rotor, and the outlet of the diffusion ring cavity of one of the adjacent two sealing units is connected to the inlet of the wedge-shaped flow channel of the other.

[0012] In some embodiments, the ratio of the inlet gap to the outlet gap of the wedge-shaped flow channel is 1.2:1 to 1.5:1; and / or, the outlet of the diffusion ring cavity is radially outside its inlet.

[0013] The present invention also provides a compressor including the above-mentioned sealing structure.

[0014] In some embodiments, the stationary member is a compressor housing, and the rotor is a rotating shaft or an impeller.

[0015] A sealing structure provided by the present invention and a compressor having the same have the following beneficial effects:

[0016] A wedge-shaped dynamic pressure sealing portion and a fluid diffusion sealing portion are simultaneously formed within the same sealing unit, forming a dynamic and static collaborative sealing mechanism for the pressure fluid, which can ensure passive adjustment of the sealing gap during the operation of equipment such as compressors that require non-contact sealing, avoid hard contact wear between the rotor and the stationary member, improve the service life of the sealing structure, and at the same time, the turbulent effect generated by the fluid diffusion sealing portion will further weaken the energy of the pressure fluid, thereby achieving the purpose of preventing gas leakage. Specifically, since the same sealing unit in the present invention simultaneously has a wedge-shaped dynamic pressure sealing portion and a fluid diffusion sealing portion, it can effectively avoid the phenomenon that a single wedge-shaped sealing structure has insufficient dynamic pressure effect, poor static sealing performance, and is prone to sudden leakage during the low-speed or start-stop stage, and at the same time, it can also avoid the phenomenon that due to rotor thermal expansion or vibration during the high-speed rotation of the rotor, the static sealing structure cannot adjust the gap, resulting in hard contact wear and leakage, reducing the sealing effect;

[0017] By arranging a rectifying channel between the wedge-shaped flow channel and the diffusion ring cavity, the fluid flowing out of the wedge-shaped flow channel can be rectified and guided so that it can enter the diffusion ring cavity tangentially along the inlet of the diffusion ring cavity. In this way, on the one hand, the fluid flowing out of the wedge-shaped flow channel can be throttled to a certain extent, and on the other hand, the direction of the fluid flowing into the diffusion ring cavity can be guided to improve the energy loss of the fluid in the diffusion ring cavity, thereby improving the sealing effect;

[0018] Designing one side wall surface of the diffusion ring cavity as an arc surface tangentially connected to the aforementioned second conical surface and limiting the central angle of the arc surface can, while ensuring smooth air flow, consume the air flow energy by increasing the turbulent reaction, and further improve the sealing performance and mechanical efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. The drawings in the following description are merely exemplary, and for those of ordinary skill in the art, without creative efforts, other implementation drawings can also be obtained based on the provided drawings.

[0020] Figure 1 is a schematic structural diagram of a sealing structure in an embodiment of the present invention, and the arrows in the figure show the flow path and direction of the fluid;

[0021] Figure 2 is Figure 1 a partial enlarged schematic view of part A in, and the arrows in the figure show the flow path and direction of the fluid;

[0022] Figure 3 is Figure 1 a partial enlarged schematic view of part B in, and the arrows in the figure show the flow path and direction of the fluid;

[0023] Figure 4 is a schematic structural diagram of some components of a compressor in another embodiment of the present invention;

[0024] Figure 5 is Figure 4 a partial enlarged view of part C in.

[0025] The reference numerals are:

[0026] 1, rotor; 11, first cylindrical surface; 12, second conical surface; 13, arc surface; 2, stationary member; 21, first conical surface; 22, third conical surface; 23, second cylindrical surface; 300, sealing unit; 31, wedge-shaped flow channel; 32, diffusion ring cavity; 33, rectifying flow channel. Detailed Embodiments

[0027] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. The description of at least one exemplary embodiment below is actually only illustrative and in no way limits the present invention and its application or use. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0028] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by orientation words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom", etc. is usually based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description. Without contrary explanations, these orientation words do not indicate and imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation on the protection scope of the present invention; the orientation words "inside, outside" refer to the inside and outside relative to the contour of each component itself.

[0029] For ease of description, spatial relative terms such as "above", "over", "on the upper surface", "upper" etc. may be used here to describe the spatial positional relationship of one device or feature shown in the drawings with other devices or features. It should be understood that the spatial relative terms are intended to cover different orientations in use or operation in addition to the orientation described in the drawings for the device. For example, if the device in the drawing is inverted, the device described as "above" or "over" other devices or structures will then be positioned "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both the orientations of "above" and "below". The device can also be positioned in other different ways (rotated 90° or in other orientations), and corresponding interpretations are made for the spatial relative descriptions used here.

[0030] In addition, it should be noted that using words such as "first", "second" etc. to define components is only for the convenience of differentiating the corresponding components. Without additional statements, the above words have no special meanings. Therefore, it should not be construed as a limitation on the protection scope of the present invention.

[0031] See Figure 1 and Figure 5As shown, according to an embodiment of the present invention, a sealing structure is provided, which includes a rotor 1 and a stationary member 2 sleeved on the radially outer side of the rotor 1. A gap is formed between the rotor 1 and the stationary member 2, and a sealing unit 300 is disposed in the gap. The sealing unit 300 includes a wedge-shaped hydrodynamic sealing portion (not labeled in the figure) and a fluid diffusion sealing portion (not labeled in the figure). The flow-through area of the inlet of the wedge-shaped flow channel 31 of the wedge-shaped hydrodynamic sealing portion is larger than that of the outlet of the wedge-shaped flow channel 31, that is, the wedge-shaped flow channel 31 is tapered in the fluid flow direction, so that the pressure fluid entering the wedge-shaped flow channel 31 gradually increases in pressure as the wedge-shaped flow channel 31 tapers, thereby achieving the purpose of reverse self-pushing away under the action of high pressure when the rotor 1 and the stationary member 2 approach axially or radially, that is, preventing hard contact wear between the two, and at the same time, the hydrodynamic effect can be used to push the fluid in the reverse direction against the leakage direction, offset the static pressure difference at the outlet of the high-pressure area (such as an impeller), increase the gas flow resistance and reduce leakage, and improve the sealing effect. The inlet of the diffusion ring cavity 32 of the fluid diffusion sealing portion communicates with the outlet of the wedge-shaped flow channel 31, and the outlet and the inlet of the diffusion ring cavity 32 are arranged in a staggered manner in the axial projection of the rotor 1 to ensure that the air flow entering the diffusion ring cavity 32 can form a staggered layer with the outflowing air flow, so as to form a turbulent effect between the inflowing air flow and the outflowing air flow and weaken the energy of the fluid. The inlet of the wedge-shaped flow channel 31 communicates with the high-pressure area, and the outlet of the diffusion ring cavity 32 communicates with the low-pressure area, that is, the wedge-shaped flow channel 31 is on the high-pressure side and the diffusion ring cavity 32 is on the low-pressure side. It can be understood that the main flow-through area of the aforementioned diffusion ring cavity 32 should be larger than the flow-through areas of its inlet and outlet to achieve throttling expansion of the fluid entering it, thereby consuming part of the energy of the gas, and further ensuring the static sealing effect of the sealing unit 300.

[0032] In this technical solution, a wedge-shaped hydrodynamic sealing portion and a fluid diffusion sealing portion are simultaneously formed in the same sealing unit 300, forming a dynamic and static collaborative sealing mechanism for pressure fluid, which can ensure passive adjustment of the sealing gap during the operation of equipment such as compressors that require non-contact sealing, avoid hard contact wear between the rotor 1 and the stationary member 2, improve the service life of the sealing structure, and at the same time, the turbulent effect generated by the fluid diffusion sealing portion will further weaken the energy of the pressure fluid, so as to achieve the purpose of preventing gas leakage. Specifically, since the same sealing unit 300 in the present invention simultaneously has a wedge-shaped hydrodynamic sealing portion and a fluid diffusion sealing portion, it can effectively avoid the phenomenon that a single wedge-shaped sealing structure has insufficient hydrodynamic effect, poor static sealing performance, and easy occurrence of sudden leakage during the low-speed or start-stop stage, and at the same time, it can also avoid the phenomenon that due to thermal expansion or vibration of the rotor 1 during the high-speed rotation of the rotor 1, hard contact wear is caused due to the inability of the static sealing structure to adjust the gap, resulting in leakage and reduction of the sealing effect.

[0033] It can be understood that the pressurized fluid enters the inlet position of the wedge-shaped flow channel 31 from the high-pressure area. Since the wedge-shaped flow channel 31 is a tapered structure, that is, the pressurized fluid flows from the wide cross-section to the narrow cross-section. As the gas flow area decreases, the gas pressure gradually rises, forming a dynamic pressure effect area. The dynamic pressure effect area pushes the pressurized fluid to resist the leakage direction in the reverse direction and offsets the static pressure difference at the outlet of the high-pressure area.

[0034] In addition, it should be particularly emphasized that the setting of the wedge-shaped flow channel 31 in the sealing unit 300 of the present invention can utilize centrifugal force to drive fluid shear to generate dynamic pressure and compensate for the axial and radial offsets of the rotor 1. Specifically, the design of the wedge-shaped structure enables the pressurized fluid, when passing through, due to the gradually narrowing gap, the fluid velocity increases. According to Bernoulli's principle, the increase in fluid velocity leads to a decrease in pressure. This pressure change helps to form a gas film. In a rotating machine, centrifugal force drives the fluid to move outward, thereby increasing the dynamic pressure of the fluid. Centrifugal force drives the fluid to move outward, resulting in relative sliding (shearing) between different layers inside the fluid. This shearing action increases the dynamic pressure of the fluid and further promotes the formation and maintenance of the gas film.

[0035] In some embodiments, the sealing unit 300 further includes a straightening channel 33 connecting the outlet of the wedge-shaped flow channel 31 and the inlet of the diffusion ring cavity 32. The straightening channel 33 is used to introduce the fluid flowing out of the outlet of the wedge-shaped flow channel 31 into the diffusion ring cavity 32 in a direction tangential to the inlet of the diffusion ring cavity 32.

[0036] In this technical solution, by arranging the straightening channel 33 between the wedge-shaped flow channel 31 and the diffusion ring cavity 32, the fluid flowing out of the wedge-shaped flow channel 31 can be rectified and guided so that it can enter the diffusion ring cavity 32 tangentially along the inlet of the diffusion ring cavity 32. In this way, on the one hand, the fluid flowing out of the wedge-shaped flow channel 31 can be throttled to a certain extent, and on the other hand, the direction of the fluid flowing into the diffusion ring cavity 32 can be guided to improve the energy loss of the fluid in the diffusion ring cavity 32, thereby improving the sealing effect.

[0037] In some embodiments, the ratio of the inlet gap to the outlet gap of the wedge-shaped flow channel 31 is 1.2:1 to 1.5:1.

[0038] In this technical solution, a larger inlet gap helps the fluid to enter the gap more easily and reduces the resistance during entry. While the smaller outlet gap can increase the fluid velocity. According to Bernoulli's principle, an increase in velocity will lead to a decrease in pressure. This pressure difference helps to form dynamic pressure, thereby improving the sealing effect.

[0039] In some embodiments, the wedge-shaped flow channel 31 is jointly formed by a first cylindrical surface 11 on the outer wall surface of the rotor 1 and a first conical surface 21 on the inner wall surface of the stationary member 2. When projected onto any axial section of the rotor 1, the inclination angle of the first conical surface 21 is 2° to 5°.

[0040] In this technical solution, when the aforementioned inclination angle is less than 2°, the change in the gap is too gentle to effectively generate the required dynamic pressure. When the aforementioned inclination angle is greater than 5°, it may increase the resistance to fluid flow, which is not conducive to the counteracting seal of the pressure fluid in the subsequent diffusion ring cavity 32.

[0041] In some embodiments, the rectifying ring channel 33 is jointly formed by a second conical surface 12 on the outer wall surface of the rotor 1 and a third conical surface 22 on the inner wall surface of the stationary member 2. The inclination angles of the second conical surface 12 and the third conical surface 22 are equal, and the second conical surface 12 gets closer to the rotor 1 along the direction away from the wedge-shaped flow channel 31. That is to say, the rectifying ring channel 33 objectively forms a conical ring gap with a constant width in the fluid flow direction. Preferably, the flow-through area of the rectifying ring channel 33 is equal to the flow-through area of the outlet of the wedge-shaped flow channel 31. That is to say, the inlet of the rectifying ring channel 33 objectively is also the outlet of the wedge-shaped flow channel 31.

[0042] In this technical solution, the rectifying ring channel 33 objectively is a flat annular gap, and the processing of this structure of the annular gap is more convenient.

[0043] In some embodiments, when projected onto any axial section of the rotor 1, the inclination angle of the second conical surface 12 is 10° to 20°.

[0044] In this technical solution, the angle design of 10° to 20° can effectively enhance the inertial effect of the fluid, so that after the air flow enters the diffusion ring cavity 32, more turbulent reactions are generated due to inertia, thereby intensifying the interaction between the air flows, helping to consume part of the air flow energy, and improving the sealing effect. On the contrary, being too large or too small will weaken the turbulent effect. At the same time, the angle range of 10° to 20° is easy to achieve in the actual manufacturing process and can be well coordinated with other parts of the mechanical system to ensure the feasibility and reliability of the overall design.

[0045] In some embodiments, the diffusion ring cavity 32 includes an arc surface 13 formed on the outer wall surface of the rotor 1 and a second cylindrical surface 23 formed on the inner wall surface of the stationary member 2. The arc surface 13 is tangentially connected to the second conical surface 12. The center of the arc surface 13 is on the side away from the rotor 1, and the central angle of the arc surface 13 is 90° to 180°.

[0046] In this technical solution, one side wall surface of the diffusion ring cavity 32 is designed as an arc surface 13 that is tangentially connected to the aforementioned second conical surface 12, and the central angle of the arc surface 13 is limited. This can, while ensuring smooth air flow, consume the air flow energy by increasing the turbulent reaction, and further improve the sealing performance and mechanical efficiency.

[0047] In a specific embodiment, the outlet of the diffusion ring cavity 32 is radially outside its inlet.

[0048] In some embodiments, specifically referring to Figure 4 and Figure 5 as shown, there are multiple groups of the sealing units 300 between the rotor 1 and the stationary member 2. Each group of the sealing units 300 is arranged in sequence along the axial direction of the rotor 1, and the outlet of the diffusion ring cavity 32 of one of the adjacent two sealing units 300 is connected to the inlet of the wedge-shaped flow channel 31 of the other, so that the sealing structure objectively forms a cascaded labyrinth comb tooth sealing structure, which can further improve the sealing performance of the sealing structure.

[0049] According to an embodiment of the present invention, there is also provided a compressor, in particular a centrifugal compressor, including the above-mentioned sealing structure. In some embodiments, the stationary member 2 is a compressor housing, and the rotor 1 is a rotating shaft or an impeller.

[0050] In this technical solution, a wedge-shaped dynamic pressure sealing portion and a fluid diffusion sealing portion are simultaneously formed within the same sealing unit 300 of the sealing structure, forming a dynamic and static collaborative sealing mechanism for pressure fluid. This can ensure passive adjustment of the sealing gap during the operation of equipment such as compressors that require non-contact sealing, avoid hard contact wear between the rotor 1 and the stationary member 2, improve the service life of the sealing structure, and at the same time, the turbulent effect generated by the fluid diffusion sealing portion will further weaken the energy of the pressure fluid, thereby achieving the purpose of preventing gas leakage. Specifically, because the same sealing unit 300 in the present invention simultaneously has a wedge-shaped dynamic pressure sealing portion and a fluid diffusion sealing portion, it can effectively avoid the phenomenon that a single wedge-shaped sealing structure has insufficient dynamic pressure effect, poor static sealing performance, and is prone to sudden leakage during the low-speed or start-stop stage, and at the same time, it can also avoid the phenomenon that during the high-speed rotation of the rotor 1, due to the thermal expansion or vibration of the rotor 1, the static sealing structure cannot adjust the gap, resulting in hard contact wear and leakage, reducing the sealing effect.

[0051] It is easy for those skilled in the art to understand that, on the premise of no conflict, the advantageous technical features of the above-mentioned various embodiments can be freely combined and superimposed.

[0052] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention. The above is only the preferred implementation manner of the present invention. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the technical principle of the present invention, several improvements and variations can still be made, and these improvements and variations should also be regarded as within the protection scope of the present invention.

Claims

1. A sealing structure, comprising a rotor (1) and a stationary member (2) sleeved on the radially outer side of the rotor (1), characterized in that, A sealing unit (300) is formed between the rotor (1) and the stationary member (2). The sealing unit (300) includes a wedge-shaped hydrodynamic seal portion and a fluid diffusion seal portion. The flow-through area of the inlet of the wedge-shaped flow channel (31) of the wedge-shaped hydrodynamic seal portion is larger than that of the outlet of the wedge-shaped flow channel (31). The inlet of the diffusion ring cavity (32) of the fluid diffusion seal portion is communicated with the outlet of the wedge-shaped flow channel (31), and the outlet and the inlet of the diffusion ring cavity (32) are arranged in a staggered manner in the axial projection of the rotor (1). The inlet of the wedge-shaped flow channel (31) is communicated with the high-pressure area, and the outlet of the diffusion ring cavity (32) is communicated with the low-pressure area.

2. The sealing structure according to claim 1, wherein The sealing unit (300) further includes a rectifying ring channel (33) that communicates the outlet of the wedge-shaped flow channel (31) and the inlet of the diffusion ring cavity (32). The rectifying ring channel (33) is used to introduce the fluid flowing out of the outlet of the wedge-shaped flow channel (31) into the diffusion ring cavity (32) in a direction tangential to the inlet of the diffusion ring cavity (32).

3. The sealing structure according to claim 2, characterized in that, The wedge-shaped flow channel (31) is jointly formed by a first cylindrical surface (11) on the outer wall surface of the rotor (1) and a first conical surface (21) on the inner wall surface of the stationary member (2). In the projection of any axial section of the rotor (1), the inclination angle of the first conical surface (21) is 2° to 5°.

4. The sealing structure according to claim 3, characterized in that, The rectifying ring channel (33) is jointly formed by a second conical surface (12) on the outer wall surface of the rotor (1) and a third conical surface (22) on the inner wall surface of the stationary member (2). The inclination angles of the second conical surface (12) and the third conical surface (22) are equal, and the second conical surface (12) gets closer to the rotor (1) along the direction away from the wedge-shaped flow channel (31).

5. The sealing structure according to claim 4, characterized in that, In the projection of any axial section of the rotor (1), the inclination angle of the second conical surface (12) is 10° to 20°; and / or, the flow-through area of the rectifying ring channel (33) is equal to the flow-through area of the outlet of the wedge-shaped flow channel (31).

6. The sealing structure according to claim 4, characterized in that, The diffusion ring cavity (32) includes an arc surface (13) formed on the outer wall surface of the rotor (1). The arc surface (13) is tangentially connected to the second conical surface (12). The center of the arc surface (13) is on the side away from the rotor (1), and the central angle of the arc surface (13) is 90° to 180°.

7. The sealing structure according to any one of claims 1 to 6, characterized in that, There are multiple groups of the sealing units (300) between the rotor (1) and the stationary member (2). Each group of the sealing units (300) is arranged in sequence along the axial direction of the rotor (1), and the outlet of the diffusion ring cavity (32) of one of the adjacent two sealing units (300) is connected to the inlet of the wedge-shaped flow channel (31) of the other.

8. The sealing structure according to claim 1, characterized in that The ratio of the inlet to outlet clearance of the wedge-shaped flow channel (31) is 1.2:1 to 1.5:1; and / or, the outlet of the diffusion ring cavity (32) is radially outside its inlet.

9. A compressor, characterized in that, It includes the sealing structure according to any one of claims 1 to 8.

10. The compressor according to claim 9, characterized in that, The stationary member (2) is a compressor housing, and the rotor (1) is a rotating shaft or an impeller.

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