Sealing structure and compressor with same
By combining the wedge-shaped hydrodynamic seal with the fluid diffusion seal, the leakage and hard contact problems caused by rotor thermal expansion or vibration in traditional comb seals in high-speed centrifuges are solved. Stable sealing performance is achieved at low speeds or during start-up and shutdown, improving the service life of the sealing structure and the gas leakage prevention effect.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- GREE ELECTRIC APPLIANCE INC OF ZHUHAI
- Filing Date
- 2025-05-16
- Publication Date
- 2026-05-08
AI Technical Summary
Traditional comb-tooth seal structures are prone to leakage or hard contact wear due to changes in clearance caused by rotor thermal expansion or vibration during high-speed centrifuge operation. Furthermore, the dynamic pressure effect is insufficient at low speeds or during start-up and shutdown, resulting in poor static sealing performance and a tendency to cause sudden leakage.
The sealing structure combines a wedge-shaped hydrodynamic seal with a fluid diffusion seal. The inlet of the wedge-shaped flow channel is larger than the outlet, and the inlet and outlet of the diffusion ring cavity are staggered. The rectifier ring channel guides the fluid into the diffusion ring cavity, forming a dynamic and static synergistic sealing mechanism, avoiding hard contact and enhancing the turbulence effect.
During high-speed rotation, hard contact wear between the rotor and stationary parts is avoided, thus extending the life of the sealing structure, reducing gas leakage, and improving sealing performance and mechanical efficiency.
Smart Images
Figure CN224214426U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of air conditioning technology, specifically relating to a sealing structure and a compressor having the same. Background Technology
[0002] Comb-tooth seals, a typical non-contact sealing structure, work by creating a series of comb-like protrusions between rotating and stationary parts. This generates a fluid damping effect, effectively suppressing gas or liquid leakage. The structure typically consists of multiple comb-like teeth arranged at intervals, resembling a comb, hence the name. In centrifugal compressors, comb-tooth seals are generally used at the impeller outlet or interstage sealing points, primarily to prevent compressed gas from leaking from high-pressure areas to low-pressure areas. When the compressor is running, high-pressure gas attempts to leak through the gaps between the teeth, but the presence of the teeth divides the gas flow path into multiple narrow channels. As the gas flows within these narrow channels, it is subjected to the combined effects of hydrodynamic pressure and frictional resistance, leading to an increased pressure drop and significantly reducing leakage.
[0003] While traditional comb-tooth seal structures offer advantages, they also have significant limitations. For instance, traditional comb-tooth seals rely on the labyrinth effect with a fixed gap for sealing. However, during high-speed centrifuge operation, the rotor's thermal expansion or vibration can cause changes in the gap, leading to leakage or hard contact wear. Furthermore, a single wedge structure lacks sufficient dynamic pressure effect at low speeds or during start-up and shutdown, resulting in poor static sealing performance and a susceptibility to sudden leaks. Additionally, the risk of hard contact between the tooth tips and the rotor is high, and over long-term operation, the gap widens, ultimately leading to seal failure. Utility Model Content
[0004] Therefore, this utility model provides a sealing structure and a compressor having the same, which can overcome the technical problems in the related technology where the sealing structure using a single labyrinth comb seal may cause changes in the gap due to the thermal expansion or vibration of the rotor during the operation of a high-speed centrifuge, which can easily lead to leakage or hard contact wear. On the other hand, the single wedge structure has insufficient dynamic pressure effect at low speed or during start-up and shutdown, poor static sealing performance, and is prone to sudden leakage.
[0005] To address the aforementioned problems, this utility model provides a sealing structure, including a rotor and a stationary component fitted radially outward of the rotor. A sealing unit is formed between the rotor and the stationary component. The sealing unit includes a wedge-shaped dynamic pressure sealing part and a fluid diffusion sealing part. The flow area of the inlet of the wedge-shaped flow channel in the wedge-shaped dynamic pressure sealing part is larger than the flow area of the outlet of the wedge-shaped flow channel. The inlet of the diffusion ring cavity in the fluid diffusion sealing part is connected to the outlet of the wedge-shaped flow channel, and the outlet and inlet of the diffusion ring cavity are misaligned on the axial projection of the rotor. The inlet of the wedge-shaped flow channel is connected to the high-pressure area, and the outlet of the diffusion ring cavity is connected to the low-pressure area.
[0006] In some embodiments, the sealing unit further includes a rectifier annular channel connecting the outlet of the wedge-shaped flow channel and the inlet of the diffusion annular cavity, the rectifier annular channel being used to introduce fluid flowing out of the outlet of the wedge-shaped flow channel into the diffusion annular cavity in a direction tangential to the inlet of the diffusion annular cavity.
[0007] In some embodiments, the wedge-shaped flow channel is formed by a first cylindrical surface on the outer wall of the rotor and a first conical surface on the inner wall of the stationary member. When projected onto any axial section of the rotor, the inclination angle of the first conical surface is 2° to 5°.
[0008] In some embodiments, the rectifier channel is formed by a second conical surface on the outer wall of the rotor and a third conical surface on the inner wall of the stationary member, wherein the second conical surface and the third conical surface have the same inclination angle, and the second conical surface gets closer and closer to the rotor along the direction away from the wedge-shaped channel.
[0009] In some embodiments, the second conical surface is tilted at an angle of 10° to 20° when projected onto any axial section of the rotor; and / or, the flow area of the rectifying annulus is equal to the flow area of the outlet of the wedge-shaped flow channel.
[0010] In some embodiments, the diffusion annular cavity includes an arcuate surface formed on the outer wall of the rotor, the arcuate surface being tangentially connected to the second conical surface, the center of the arcuate surface being located on the side away from the rotor, and the central angle of the arcuate surface being 90° to 180°.
[0011] In some embodiments, there are multiple sets of sealing units between the rotor and the stationary member, each set of sealing units being arranged sequentially along the axial direction of the rotor, and the outlet of a diffusion annular cavity in one of two adjacent sealing units being connected to the inlet of a wedge-shaped flow channel in the other.
[0012] In some embodiments, the inlet-to-outlet gap ratio of the wedge-shaped flow channel is 1.2:1 to 1.5:1; and / or, the outlet of the diffusion annular cavity is located radially outside its inlet.
[0013] This utility model also provides a compressor, including the above-described sealing structure.
[0014] In some embodiments, the stationary component is a compressor housing, and the rotor is a shaft or an impeller.
[0015] The sealing structure and compressor having the same provided by this utility model have the following beneficial effects:
[0016] Within the same sealing unit, both a wedge-shaped dynamic pressure seal and a fluid diffusion seal are formed, creating a dynamic and static synergistic sealing mechanism for pressurized fluids. This ensures passive adjustment of the sealing gap during operation of equipment requiring non-contact sealing, such as compressors, avoiding hard contact wear between the rotor and stationary parts, and extending the service life of the sealing structure. Simultaneously, the turbulence effect generated by the fluid diffusion seal further weakens the energy of the pressurized fluid, thereby preventing gas leakage. Specifically, because the same sealing unit in this invention simultaneously possesses a wedge-shaped dynamic pressure seal and a fluid diffusion seal, it effectively avoids the problems of insufficient dynamic pressure effect, poor static sealing performance, and easy sudden leakage caused by a single wedge-shaped seal structure during low-speed or start-stop phases. Furthermore, it prevents leakage and reduced sealing effectiveness caused by hard contact wear due to the inability of the static seal structure to adjust the gap during high-speed rotor rotation caused by rotor thermal expansion or vibration.
[0017] By setting a rectifying annular channel between the wedge-shaped flow channel and the diffuser ring cavity, the fluid flowing out of the wedge-shaped flow channel can be rectified and guided, so that it can enter the diffuser ring cavity tangentially along the inlet of the diffuser ring cavity. In this way, the fluid flowing out of the wedge-shaped flow channel can be throttled to a certain extent, and the direction of the fluid flowing into the diffuser ring cavity can be guided, so as to improve the energy loss of the fluid in the diffuser ring cavity and thus improve the sealing effect.
[0018] Designing one side wall of the diffuser annular cavity as an arc surface tangentially connected to the aforementioned second conical surface, and limiting the central angle of this arc surface, can ensure smooth airflow while increasing turbulent reaction to consume airflow energy, thereby further improving sealing performance and mechanical efficiency. Attached Figure Description
[0019] To more clearly illustrate the embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. The drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.
[0020] Figure 1 This is a schematic diagram of the sealing structure in one embodiment of the present invention. The arrows in the diagram indicate the flow path and direction of the fluid.
[0021] Figure 2 yes Figure 1 A magnified view of a portion of point A in the diagram, with arrows indicating the flow path and direction of the fluid;
[0022] Figure 3 yes Figure 1 A magnified view of a portion of point B, with arrows indicating the flow path and direction of the fluid.
[0023] Figure 4 This is a schematic diagram of the structure of some components of the compressor in another embodiment of the present invention;
[0024] Figure 5 yes Figure 4 A magnified view of a section at point C.
[0025] The attached figures are labeled as follows:
[0026] 1. Rotor; 11. First cylindrical surface; 12. Second conical surface; 13. Arc surface; 2. Stationary component; 21. First conical surface; 22. Third conical surface; 23. Second cylindrical surface; 300. Sealing unit; 31. Wedge-shaped flow channel; 32. Diffusion annular cavity; 33. Rectifying annular channel. Detailed Implementation
[0027] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present utility model or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the scope of protection of the present utility model.
[0028] In the description of this utility model, it should be understood that the directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this utility model. The directional terms "inner" and "outer" refer to the inner and outer contours of each component itself.
[0029] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90° or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.
[0030] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be construed as limiting the scope of protection of this utility model.
[0031] See Figure 1 and Figure 5As shown, according to an embodiment of the present invention, a sealing structure is provided, including a rotor 1 and a stationary member 2 fitted radially outside the rotor 1. A gap is formed between the rotor 1 and the stationary member 2. A sealing unit 300 is provided within the gap. The sealing unit 300 includes a wedge-shaped dynamic pressure sealing part (not labeled in the figure) and a fluid diffusion sealing part (not labeled in the figure). The flow area of the inlet of the wedge-shaped flow channel 31 of the wedge-shaped dynamic pressure sealing part is larger than the flow area of the outlet of the wedge-shaped flow channel 31. That is, the wedge-shaped flow channel 31 has a gradually narrowing structure in the direction of fluid flow. This causes the pressure fluid entering the wedge-shaped flow channel 31 to gradually increase with the gradual narrowing pressure of the wedge-shaped flow channel 31, thereby achieving the purpose of reverse self-pushing away under high pressure when the rotor 1 and the stationary member 2 are close together in the axial or radial direction. This prevents hard contact wear between the two and also utilizes the dynamic pressure effect to push the fluid in the opposite direction to resist leakage, offsetting the static pressure difference at the outlet of the high-pressure zone (e.g., impeller), increasing gas flow resistance to reduce leakage and improve sealing effect. The inlet of the diffusion ring cavity 32 of the fluid diffusion sealing part is connected to the outlet of the wedge-shaped flow channel 31, and the outlet and inlet of the diffusion ring cavity 32 are staggered on the axial projection of the rotor 1 to ensure that the airflow entering the diffusion ring cavity 32 can form a staggered layer with the outflowing airflow, thereby realizing the formation of turbulence effect between the inflowing airflow and the outflowing airflow and weakening the energy of the fluid. The inlet of the wedge-shaped flow channel 31 is connected to the high-pressure zone, and the outlet of the diffusion ring cavity 32 is connected to the low-pressure zone, 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 is understandable that the main flow area of the aforementioned diffusion ring cavity 32 should be larger than the flow area of its inlet and outlet, so as to achieve throttling expansion of the fluid entering it, thereby consuming part of the energy of the gas, and thus ensuring the static sealing effect of the sealing unit 300.
[0032] In this technical solution, a wedge-shaped dynamic pressure sealing part and a fluid diffusion sealing part are simultaneously formed within the same sealing unit 300, creating a dynamic and static synergistic sealing mechanism for the pressurized fluid. This ensures passive adjustment of the sealing gap during the operation of equipment requiring non-contact sealing, such as compressors, avoiding hard contact wear between the rotor 1 and the stationary part 2, and extending the service life of the sealing structure. Simultaneously, the turbulence effect generated by the fluid diffusion sealing part further weakens the energy of the pressurized fluid, thereby preventing gas leakage. Specifically, because the same sealing unit 300 in this invention simultaneously possesses a wedge-shaped dynamic pressure sealing part and a fluid diffusion sealing part, it effectively avoids the phenomena of insufficient dynamic pressure effect, poor static sealing performance, and easy sudden leakage caused by a single wedge-shaped sealing structure during low-speed or start-stop phases. Furthermore, it prevents leakage and reduced sealing effect caused by hard contact wear due to the inability of the static sealing structure to adjust the gap during high-speed rotation of the rotor 1 caused by the thermal expansion or vibration of the rotor 1.
[0033] It is understandable that the pressure fluid enters the inlet of the wedge-shaped flow channel 31 from the high-pressure zone. Since the wedge-shaped flow channel 31 has a tapered structure, that is, the pressure fluid flows from the wide cross section to the narrow cross section. As the gas flow area decreases, the gas pressure gradually increases, forming a dynamic pressure effect region. The dynamic pressure effect region pushes the pressure fluid in the opposite direction to resist the leakage direction and offsets the static pressure difference at the outlet of the high-pressure zone.
[0034] Furthermore, it is particularly important to emphasize that the wedge-shaped flow channel 31 within the sealing unit 300 of this invention can utilize centrifugal force to drive fluid shearing and generate dynamic pressure, compensating for the axial and radial offset of the rotor 1. Specifically, the wedge-shaped structure design causes the pressure fluid to increase in velocity as the gap gradually narrows. According to Bernoulli's principle, the increase in fluid velocity leads to a decrease in pressure, and this pressure change helps to form an air film. In rotating machinery, centrifugal force drives the fluid outward, thereby increasing the fluid's dynamic pressure. This outward movement of the fluid also causes relative sliding (shearing) between different layers within the fluid. This shearing action increases the fluid's dynamic pressure, further promoting the formation and maintenance of the air film.
[0035] In some embodiments, the sealing unit 300 further includes a rectifier annular channel 33 connecting the outlet of the wedge-shaped flow channel 31 and the inlet of the diffusion annular cavity 32, the rectifier annular channel 33 being used to introduce fluid flowing out of the outlet of the wedge-shaped flow channel 31 into the diffusion annular cavity 32 in a direction tangential to the inlet of the diffusion annular cavity 32.
[0036] In this technical solution, by setting a rectifying annular channel 33 between the wedge-shaped flow channel 31 and the diffuser annular cavity 32, the fluid flowing out of the wedge-shaped flow channel 31 can be rectified and guided, so that it can enter the diffuser annular cavity 32 tangentially along the inlet of the diffuser annular 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 diffuser annular cavity 32 can be guided, so as to improve the energy loss of the fluid in the diffuser annular cavity 32, thereby improving the sealing effect.
[0037] In some embodiments, the inlet-to-outlet gap ratio 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 enter the gap more easily and reduces the resistance when entering, while a smaller outlet gap can increase the fluid velocity. According to Bernoulli's principle, the 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 formed by a first cylindrical surface 11 on the outer wall of the rotor 1 and a first conical surface 21 on the inner wall 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 tilt angle is less than 2°, the gap change is too gradual to effectively generate the required dynamic pressure. When the aforementioned tilt 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 annular channel 33 is formed by a second conical surface 12 on the outer wall of the rotor 1 and a third conical surface 22 on the inner wall of the stationary member 2. The second conical surface 12 and the third conical surface 22 have the same inclination angle, and the second conical surface 12 gets closer and closer to the rotor 1 along the direction away from the wedge-shaped flow channel 31. That is, the rectifying annular channel 33 objectively forms a conical annular gap of equal width in the fluid flow direction. Preferably, the flow area of the rectifying annular channel 33 is equal to the flow area of the outlet of the wedge-shaped flow channel 31. That is, the inlet of the rectifying annular channel 33 is also the outlet of the wedge-shaped flow channel 31.
[0042] In this technical solution, the rectifier ring channel 33 is objectively a straight annular gap, and the annular gap of this structure is more convenient to process.
[0043] In some embodiments, the tilt angle of the second conical surface 12 is 10° to 20° when projected onto any axial section of the rotor 1.
[0044] In this technical solution, the 10° to 20° angle design effectively enhances the inertial effect of the fluid, causing the airflow to generate more turbulent reactions due to inertia after entering the diffuser annular cavity 32. This intensifies the interaction between airflows, helps to consume some airflow energy, and improves the sealing effect. Conversely, an angle that is too large or too small will weaken the turbulence effect. At the same time, the 10° to 20° angle range is easy to achieve in actual manufacturing and can be well integrated with other parts of the mechanical system, ensuring the feasibility and reliability of the overall design.
[0045] In some embodiments, the diffusion annular cavity 32 includes an arcuate surface 13 formed on the outer wall of the rotor 1 and a second cylindrical surface 23 formed on the inner wall of the stationary member 2. The arcuate surface 13 is tangentially connected to the second conical surface 12. The center of the arcuate surface 13 is located on the side away from the rotor 1, and the central angle of the arcuate surface 13 is 90° to 180°.
[0046] In this technical solution, one side wall of the diffusion annular 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 ensure smooth airflow while increasing turbulent reaction to consume airflow energy, thereby further improving sealing performance and mechanical efficiency.
[0047] In one specific embodiment, the outlet of the diffusion annular cavity 32 is located radially outside its inlet.
[0048] In some implementation methods, see details. Figure 4 and Figure 5 As shown, there are multiple sets of sealing units 300 between the rotor 1 and the stationary part 2. Each set of sealing units 300 is arranged sequentially along the axial direction of the rotor 1, and the outlet of the diffusion annular cavity 32 of one of the two adjacent 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 sealing structure, which can further improve the sealing performance of the sealing structure.
[0049] According to an embodiment of the present invention, a compressor, particularly a centrifugal compressor, is also provided, including the above-described sealing structure. In some embodiments, the stationary component 2 is a compressor housing, and the rotor 1 is a rotating shaft or an impeller.
[0050] In this technical solution, the sealing structure simultaneously forms a wedge-shaped dynamic pressure sealing part and a fluid diffusion sealing part within the same sealing unit 300, creating a dynamic and static synergistic sealing mechanism for the pressurized fluid. This ensures passive adjustment of the sealing gap during the operation of equipment requiring non-contact sealing, such as compressors, avoiding hard contact wear between the rotor 1 and the stationary part 2, thus extending the service life of the sealing structure. Simultaneously, the turbulence effect generated by the fluid diffusion sealing part further weakens the energy of the pressurized fluid, thereby preventing gas leakage. Specifically, because the same sealing unit 300 in this invention simultaneously possesses a wedge-shaped dynamic pressure sealing part and a fluid diffusion sealing part, it effectively avoids the phenomena of insufficient dynamic pressure effect, poor static sealing performance, and easy sudden leakage caused by a single wedge-shaped sealing structure during low-speed or start-stop phases. Furthermore, it prevents leakage and reduced sealing effect caused by hard contact wear due to the inability of the static sealing structure to adjust the gap during high-speed rotation of the rotor 1 caused by the thermal expansion or vibration of the rotor 1.
[0051] It will be readily understood by those skilled in the art that, without conflict, the advantageous technical features of the above-mentioned methods can be freely combined and superimposed.
[0052] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model. The above description is only a preferred embodiment of this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of this utility model, and these improvements and modifications should also be considered within the protection scope of this utility model.
Claims
1. A sealing structure comprising a rotor (1) and a stationary member (2) fitted radially outward of the rotor (1), characterized in that, A sealing unit (300) is formed between the rotor (1) and the stationary part (2). The sealing unit (300) includes a wedge-shaped dynamic pressure sealing part and a fluid diffusion sealing part. The flow area of the inlet of the wedge-shaped flow channel (31) of the wedge-shaped dynamic pressure sealing part is greater than the flow area of the outlet of the wedge-shaped flow channel (31). The inlet of the diffusion ring cavity (32) of the fluid diffusion sealing part is connected to the outlet of the wedge-shaped flow channel (31). The outlet and inlet of the diffusion ring cavity (32) are misaligned on the axial projection of the rotor (1). The inlet of the wedge-shaped flow channel (31) is connected to the high-pressure area, and the outlet of the diffusion ring cavity (32) is connected to the low-pressure area.
2. The sealing structure according to claim 1, characterized in that, The sealing unit (300) further includes a rectifier ring channel (33) connecting the outlet of the wedge-shaped flow channel (31) and the inlet of the diffusion ring cavity (32), the rectifier ring channel (33) being 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 formed by a first cylindrical surface (11) on the outer wall of the rotor (1) and a first conical surface (21) on the inner wall 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°.
4. The sealing structure according to claim 3, characterized in that, The rectifier ring channel (33) is formed by a second conical surface (12) on the outer wall of the rotor (1) and a third conical surface (22) on the inner wall of the stationary member (2). The second conical surface (12) and the third conical surface (22) have the same inclination angle, and the second conical surface (12) gets closer and 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, Projected onto any axial section of the rotor (1), the inclination angle of the second conical surface (12) is 10° to 20°; and / or, the flow area of the rectifying annulus (33) is equal to the flow area of the outlet of the wedge-shaped flow channel (31).
6. The sealing structure according to claim 4, characterized in that, The diffusion annular cavity (32) includes an arc surface (13) formed on the outer wall 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 located 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 sets of sealing units (300) between the rotor (1) and the stationary part (2). Each set of sealing units (300) is arranged sequentially along the axial direction of the rotor (1), and the outlet of the diffusion annular cavity (32) of one of the two adjacent sealing units (300) is connected to the inlet of the wedge-shaped flow channel (31).
8. The sealing structure according to claim 1, characterized in that, The inlet-to-outlet gap ratio of the wedge-shaped flow channel (31) is 1.2:1 to 1.5:1; and / or, the outlet of the diffusion annular cavity (32) is located radially outside its inlet.
9. A compressor, characterized in that, The sealing structure includes any one of claims 1 to 8.
10. The compressor according to claim 9, characterized in that, The stationary component (2) is the compressor housing, and the rotor (1) is a shaft or impeller.