Cylindrical surface gas film sealing structure of tooth-shaped pressurizing groove

Abstract

The invention relates to a cylindrical surface gas film sealing structure of a tooth-shaped pressurizing groove. The cylindrical surface air film sealing structure of the tooth-shaped pressurization groove comprises a rear end cover and a front end cover which are arranged on a floating ring and a movable ring in a sleeving mode. The tooth-shaped pressurizing grooves are circumferentially arrayed in the peripheral surface of the movable ring at equal intervals, and each tooth-shaped pressurizing groove comprises a tooth-free feature groove area a and a tooth-shaped feature groove area b. Compared with a traditional linear groove design, the tooth-shaped pressurizing grooves are formed in the peripheral surface of the movable ring at equal intervals in the circumferential array mode, tooth-shaped feature groove areas b of the tooth-shaped pressurizing grooves are provided with tooth-shaped structures protruding towards the interiors of the grooves, and the tooth-shaped structures form contraction type channels in the gas flowing direction; when gas flows into the tooth-shaped characteristic groove area b through the tooth-shaped characteristic groove area a, the sectional area of a flowing channel of the tooth-shaped characteristic groove area b is reduced in the gas flowing direction, so that the hydrodynamic effect is enhanced, the buoyancy force of a gas film is improved, the supporting effect on a floating ring is improved, the stability of the gas film is enhanced, the leakage rate is reduced, and the sealing performance is improved.

Description

Technical Field

[0001] The present application relates to the technical field of cylindrical air film sealing, and in particular to a cylindrical air film sealing structure of a toothed boosting groove. Background Art

[0002] With the increasing demand for sealing technology in aerospace, petrochemical and other fields, the importance of sealing technology in production and technology has attracted more and more attention from researchers.

[0003] Cylindrical air film seal is a new type of non-contact sealing technology based on micron-level air film lubrication. It has the advantages of low leakage and is suitable for high speed and high pressure occasions. Its working principle is based on the theory of fluid dynamic pressure lubrication. The specific process is as follows: When the cylindrical air film seal is working, the dynamic ring and the floating ring are eccentrically installed. When the rotor rotates, the gas in the sealing gap is driven from the larger gap side to the smaller gap side by the boundary friction of the passive ring. In the process of gradual convergence of the air film gap, the gas is compressed and the pressure increases. This phenomenon is the fluid dynamic pressure effect. Under the action of dynamic pressure, the floating ring will move toward the center of the dynamic ring, and the eccentricity between the dynamic ring and the floating ring will gradually decrease, and finally tend to be concentric and enter a stable operating state. When the sealing system is disturbed and eccentric, resulting in a smaller gap on one side, the fluid dynamic pressure effect causes the floating ring to shift to the side with thicker air film to restore a new equilibrium state. Through this dynamic adjustment process, the fluid dynamic pressure, the force generated by the deformation of the floating ring, and the gas friction force are balanced to ensure the stability and effectiveness of the sealing system.

[0004] The traditional cylindrical gas film seal structure usually adopts a straight groove design, that is, a straight groove is opened on the surface of the dynamic ring. However, due to its single shape, it is difficult to effectively restrict the flow direction and flow rate of the gas, so that when the dynamic ring rotates at high speed, the gas is easy to form a turbulent flow state in the groove and cannot flow along the expected path, resulting in the gas not being able to fully exert its dynamic pressure effect, limiting the support for the floating ring, and thus reducing the sealing performance. Summary of the invention

[0005] In order to solve or partially solve the problems existing in the related art, the present application provides a cylindrical air film sealing structure of a toothed boosting groove.

[0006] To achieve the above objectives, this application is implemented through the following technical solutions:

[0007] A cylindrical air film sealing structure of a tooth-shaped boosting groove comprises a floating ring, a dynamic ring and a main shaft, wherein a layer of micrometer-level cylindrical air film is formed between the floating ring and the dynamic ring, and the cylindrical air film sealing structure of the tooth-shaped boosting groove further comprises:

[0008] The rear end cover and the front end cover are mounted on the floating ring and the moving ring;

[0009] A plurality of tooth-shaped boosting grooves are arranged in a circumferential array at equal intervals on the outer peripheral surface of the moving ring, each tooth-shaped boosting groove comprises a groove area a without tooth-shaped features and a groove area b with tooth-shaped features;

[0010] Among them, a tooth-shaped structure protruding into the groove is provided in the tooth-shaped characteristic groove area b, and the tooth-shaped structure forms a contraction channel along the gas flow direction, so that when the gas flows into the tooth-shaped characteristic groove area b through the non-tooth-shaped characteristic groove area a, the cross-sectional area of ​​the flow channel decreases along the gas flow direction.

[0011] Optionally, a plurality of flexible goose-shaped support members are provided between the floating ring and the rear end cover.

[0012] Optionally, the wing tip portion of the flexible goose-shaped support has an arc shape that matches the outer periphery of the floating ring, and the radius of the arc shape is consistent with the radius of the outer periphery of the floating ring.

[0013] Optionally, the floating ring is connected to the front end cover via a positioning pin, and the floating ring is connected to the rear end cover via a spring.

[0014] Optionally, the rear end cover and the front end cover are connected by hexagon socket bolts, and a sealing ring is provided at the connection between the two.

[0015] Optionally, the side of the cylindrical air film close to the rear end cover is the high-pressure gas side, and the side close to the front end cover is the low-pressure gas side.

[0016] Optionally, a cylindrical area between adjacent tooth-shaped boost grooves and a cylindrical area between the tooth-shaped boost grooves and the low-pressure gas side form a sealing dam.

[0017] Optionally, the slot end of the tooth-shaped boosting slot extends along its axial outer side to communicate with the high-pressure gas side to form an air inlet.

[0018] Optionally, the groove bottom end of the tooth-shaped boost groove extends along the axial inner side thereof to the sealing dam to form a groove root.

[0019] Optionally, the non-toothed characteristic groove area a constitutes the leeward side, and the toothed characteristic groove area b constitutes the windward side.

[0020] The beneficial effects of the present application are as follows: compared with the traditional straight groove design, the present application opens a number of tooth-shaped boosting grooves in an evenly spaced circular array on the outer circumferential surface of the dynamic ring. The tooth-shaped characteristic groove area b of the tooth-shaped boosting groove has a tooth-like structure protruding into the groove. The tooth-like structure forms a contraction channel along the gas flow direction, so that when the gas flows into the tooth-shaped characteristic groove area b through the tooth-free characteristic groove area a, the cross-sectional area of ​​the flow channel decreases along the gas flow direction, thereby enhancing the fluid dynamic pressure effect, improving the buoyancy of the air film, improving the support effect on the floating ring, enhancing the stability of the air film, thereby reducing leakage and improving the sealing performance.

[0021] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and other objects, features and advantages of the present application will become more apparent through a more detailed description of exemplary embodiments of the present application in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments of the present application.

[0023] Figure 1 is a structural schematic diagram of a cylindrical air film sealing structure shown in an embodiment of the present application;

[0024] Figure 2 is a schematic structural diagram of a tooth-shaped supercharging groove shown in an embodiment of the present application;

[0025] Figure 3 is a schematic diagram of the three-dimensional structure of a flexible goose-shaped support member shown in an embodiment of the present application;

[0026] Figure 4 is a side view of a flexible goose-shaped support member shown in an embodiment of the present application;

[0027] Figure 5 is a schematic cross-sectional structural diagram of a cylindrical air film sealing structure shown in an embodiment of the present application;

[0028] Figure 6 This is a detailed diagram of the sealing ring installation shown in the embodiment of the present application.

[0029] Figure numerals: 1 rear end cover, 2 hexagon socket bolt, 3 sealing ring, 4 flexible goose-shaped support, 5 spring, 6 floating ring, 7 dynamic ring, 8 main shaft, 9 positioning pin, 10 front end cover, 11 toothed boost groove, 12 wing tip part, 13 goose wing part. DETAILED DESCRIPTION

[0030] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0031] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0032] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific situation.

[0033] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0034] In the present application, the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0035] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

[0036] The above description is only an optional embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

[0037] In order to make the purpose, technical solutions and beneficial effects of the present application clearer, the preferred embodiments of the present application will be described in detail below in conjunction with the accompanying drawings to facilitate understanding by technical personnel.

[0038] Embodiment 1:

[0039] See also Figure 1 and Figure 2 A cylindrical air film sealing structure of a tooth-shaped boosting groove comprises a floating ring 6, a dynamic ring 7 and a main shaft 8, a micron-level cylindrical air film is formed between the floating ring 6 and the dynamic ring 7, and the cylindrical air film sealing structure of the tooth-shaped boosting groove further comprises:

[0040] The rear end cover 1 and the front end cover 10 are mounted on the floating ring 6 and the moving ring 7;

[0041] A plurality of tooth-shaped boosting grooves 11 are arranged in a circumferential array at equal intervals on the outer peripheral surface of the moving ring 7, and each tooth-shaped boosting groove 11 includes a groove area a without tooth-shaped features and a groove area b with tooth-shaped features;

[0042] Among them, a tooth-shaped structure protruding into the groove is provided in the tooth-shaped characteristic groove area b, and the tooth-shaped structure forms a contraction channel along the gas flow direction, so that when the gas flows into the tooth-shaped characteristic groove area b through the non-tooth-shaped characteristic groove area a, the cross-sectional area of ​​the flow channel decreases along the gas flow direction.

[0043] Specifically, the moving ring 7 is coaxially mounted on the main shaft 8, and the main shaft 8 and the moving ring 7 are interference fit to ensure that the main shaft 8 rotates with the moving ring 7 at high speed. The floating ring 6 is eccentrically mounted on the moving ring 7, and one end of the floating ring 6 is mounted on the front end cover 10, and the other end is mounted on the rear end cover 1. The front end cover 10 is connected to the rear end cover 1, and the rear end cover 1 is mounted on an external device.

[0044] A number of tooth-shaped boosting grooves 11 are formed in an evenly spaced circular array on the outer surface of the moving ring 7, and each tooth-shaped boosting groove 11 includes a groove area a without tooth-shaped features and a groove area b with tooth-shaped features. From a macroscopic point of view, when the gas flows in the tooth-shaped boosting groove 11, the existence of the tooth shape is equivalent to adding many protruding and concave parts to the originally relatively smooth flow channel. When the gas flows from the area without tooth-shaped feature groove area a to the area with tooth-shaped feature groove area b, the gas needs to flow between these teeth, and the space between the teeth is relatively narrow, forming a contraction channel, resulting in a reduction in the effective cross-sectional area through which the gas flows.

[0045] In the tooth-shaped boosting groove 11, the flow direction of the gas is not completely along a straight line, but will change due to the influence of the tooth-shaped structure. When the gas flows to the tooth-shaped area, it will be forced to flow along the contour and angle of the tooth shape. This change in flow direction will cause the gas to converge in a local area. In the process of gas convergence, the originally dispersed gas will flow in a smaller space, resulting in a reduction in cross-sectional area.

[0046] Compared with the traditional straight groove, the special tooth structure of the tooth-shaped characteristic groove area b makes the gas flow more regularly after entering the groove due to the obstruction and guidance of the groove wall. When the moving ring 7 rotates at high speed, the gas flows along the specific path of the tooth-shaped boosting groove 11, and it is not easy to have turbulence. When the gas flows from the non-tooth-shaped characteristic groove area a to the tooth-shaped characteristic groove area b, the flow rate and flow direction of the gas can be effectively controlled under the effect of the change in cross-sectional area, and it can better flow from the high-pressure side to the low-pressure side, forming a stable gas film, and enhancing the guiding effect on the gas.

[0047] Under complex working conditions, the tooth-shaped boosting groove 11 can optimize the gas flow and pressure distribution. On the one hand, when the gas flows through the tooth-shaped boosting groove 11, the cross-sectional area of ​​the gas channel changes due to the tooth-shaped structure. According to the law of conservation of flow, the gas flow rate will change, and then the dynamic pressure will change. The tooth-shaped characteristics of the tooth-shaped characteristic groove area b increase the gas flow rate and the dynamic pressure, forming a more reasonable pressure gradient in the sealing gap. On the other hand, when the floating ring 6 is offset due to external interference, the tooth-shaped boosting groove 11 can adjust the gas flow and pressure distribution according to the position change of the floating ring 6. For example, when the gap on one side becomes smaller, the tooth-shaped boosting groove 11 can guide more gas to flow to that side, increase the gas pressure on that side, and cause the floating ring 6 to shift to the side with a thicker air film, restore the equilibrium state, and improve the adaptability of the air film seal under complex working conditions.

[0048] When the main shaft 8 rotates at a predetermined speed, the gas flows along the shaft due to viscous friction, and flows from the side with a larger gap between the moving ring 7 and the floating ring 6 when eccentrically installed to the side with a smaller gap. Under the action of the convergent gap, the gas is squeezed to increase the pressure, and a gas film several microns thick is formed in this area. At the same time, the design of the toothed boosting groove 11 on the moving ring 7 significantly enhances the dynamic pressure effect. Multiple changes in cross-sectional area increase the dynamic pressure continuously, providing a stronger buoyancy for the floating ring 6. Under complex working conditions such as high speed and high pressure difference, this enhanced dynamic pressure effect can effectively improve the bearing capacity of the air film, ensure that the floating ring 6 and the moving ring 7 maintain a stable non-contact state, reduce leakage, and meet the requirements of aircraft engines for high performance of air film sealing. As the fluid dynamic pressure on the floating ring 6 exceeds the sum of its own gravity and friction, the floating ring 6 moves toward the geometric center, resulting in a decrease in eccentricity, thereby reducing the fluid dynamic pressure. When the fluid dynamic pressure is lower than the sum of the gravity and friction of the floating ring 6, the floating ring 6 will move in the opposite direction. Through this repeated movement, the fluid dynamic pressure, gravity and friction force finally reach a dynamic balance, completing the fluid sealing process.

[0049] To sum up, compared with the traditional straight groove design, the present application opens a number of tooth-shaped boosting grooves 11 in an evenly spaced circular array on the outer surface of the dynamic ring 7. The tooth-shaped characteristic groove area b of the tooth-shaped boosting groove 11 has a tooth-like structure protruding into the groove, and the tooth-like structure forms a contraction channel along the gas flow direction, so that when the gas flows into the tooth-shaped characteristic groove area b through the non-tooth-shaped characteristic groove area a, the cross-sectional area of ​​the flow channel decreases along the gas flow direction, thereby enhancing the fluid dynamic pressure effect, improving the buoyancy of the air film, improving the support effect on the floating ring, enhancing the stability of the air film, thereby reducing leakage and improving the sealing performance.

[0050] Embodiment 2:

[0051] See also Figure 3 and Figure 4 Based on the first embodiment, optionally, a plurality of flexible goose-shaped support members 4 are provided between the floating ring 6 and the rear end cover 1 .

[0052] Optionally, the wing tip portion 12 of the flexible goose-shaped support member 4 has an arc shape that matches the outer periphery of the floating ring 6 , and the radius of the arc shape is consistent with the radius of the outer periphery of the floating ring 6 .

[0053] Specifically, one end of the flexible goose-shaped support member 4 is fixed to the inner wall of the rear end cover 1, and the other end is in contact with the outer wall of the floating ring 6. Due to the continuous change of the position of the floating ring 6, the goose wing portion 13 of the flexible goose-shaped support member 4 will undergo elastic deformation to continuously support the floating ring 6. After the work stops, the arc structure of the wing tip portion 12 will help the floating ring return to the correct eccentric position, playing a positioning role.

[0054] In this embodiment, by providing a flexible goose-shaped support member 4, collision and friction of the sealing pair can be avoided under large radial displacement conditions, and seal failure can be prevented. The floating ring can be ensured to be correctly eccentrically installed after frequent start and stop of the sealing mechanism and after being acted upon by external forces, thereby ensuring the reliability of the sealing structure. In addition, the deformation of the flexible goose-shaped support member 4 itself has the characteristics of adjusting stiffness and damping, and can operate smoothly under complex working conditions.

[0055] Embodiment three:

[0056] See also Figure 5 and Figure 6 Based on the above embodiment, optionally, the floating ring 6 is connected to the front end cover 10 via a positioning pin 9 , and the floating ring 6 is connected to the rear end cover 1 via a spring 5 .

[0057] Specifically, the positioning pin 9 is used to ensure the accurate relative position of the floating ring 6 and the front cover 10 during assembly, so as to avoid sealing failure or mechanical interference due to position deviation; during the operation of the equipment, the positioning pin can prevent the floating ring 6 from rotating or axially moving relative to the front cover 10; the positioning pin 9 provides guidance for disassembly and assembly, shortens the maintenance time, and avoids damage to parts due to manual centering errors; the positioning pin 9 can be used as a "guide column" to help quickly align the installation position of the floating ring 6 and the front cover 10, thereby improving installation efficiency.

[0058] One end of the spring 5 is connected to the floating ring 6, and the other end is connected to the rear end cover 1. The elastic deformation ability of the spring 5 can absorb the axial / radial displacement of the floating ring 6 and the rear end cover 1 caused by temperature changes or processing errors, thereby avoiding stress concentration caused by rigid connection; the flexibility of the spring 5 can attenuate vibration or impact during equipment operation, thereby protecting the floating ring 6 and the rear end cover 1 from fatigue damage.

[0059] Optionally, the rear end cover 1 is connected to the front end cover 10 via a hexagon socket bolt 2, and a sealing ring 3 is provided at the connection between the two.

[0060] Specifically, the rear end cover 1 and the front end cover 10 are tightly connected by the hexagon socket bolts 2, and the hexagon socket bolts 2 are used to facilitate disassembly in a narrow space;

[0061] In this embodiment, the sealing ring 3 is installed in the groove between the rear cover 1 and the front cover 10. The sealing ring 3 serves as a static seal to fill the microscopic gap of the end cover joint surface, prevent external gas / liquid from directly invading the interior of the sealing structure, and avoid external pressure fluctuations from interfering with the pressure field of the toothed groove air film; the toothed booster groove 11 relies on the air film thickness (usually micrometer level) to achieve non-contact sealing, and the sealing ring 3 can prevent the environmental medium from penetrating to cause air film dilution or local pressure imbalance, ensuring uniform air film load. In this way, the sealing ring 3 makes the internal pressure distribution of the cylindrical air film sealing structure of the toothed booster groove 11 unaffected by the outside world.

[0062] Optionally, the side of the cylindrical air film close to the rear end cover 1 is the high-pressure gas side, and the side close to the front end cover 10 is the low-pressure gas side.

[0063] Specifically, an air film pressure gradient is formed by the high-pressure gas side and the low-pressure gas side to drive the air film flow. The air film pressure gradient offsets the radial force of the shaft system to ensure that the floating ring 6 and the moving ring 7 are not in direct contact, thereby reducing friction power consumption. When the operating conditions fluctuate (such as pressure and temperature changes) and cause the thickness of the air film to decrease, the throttling effect of the high-pressure side gas through the tooth groove is automatically compensated to maintain the air film stiffness. During the startup / shutdown process, the pressure gradient helps to quickly establish the air film to avoid dry friction.

[0064] Optionally, the cylindrical area between the adjacent tooth-shaped boost grooves 11 and the cylindrical area between the tooth-shaped boost grooves 11 and the low-pressure gas side form a sealing dam.

[0065] Specifically, the tooth-shaped booster groove 11 is a concave structure, and the sealing dam is a raised area between adjacent tooth-shaped booster grooves 11. The two cooperate with each other to form a unique "tooth groove-dam" alternating structure. The sealing dam decomposes the pressure difference (ΔP) from the high-pressure side to the low-pressure side into multiple stages. The sealing dam between adjacent tooth grooves reduces the flow area, forcing the gas to produce a local throttling effect when passing through the narrow gap, forming a stepped pressure drop. Multi-stage throttling can significantly reduce the leakage rate. The raised structure of the sealing dam induces the gas to produce local vortices during rotation, forming a high-pressure air cushion layer. This pressure distribution can offset the radial force of the shaft system, so that the floating ring 6 and the dynamic ring 7 maintain a stable air film gap.

[0066] Optionally, the slot end of the tooth-shaped boosting slot 11 extends along the axial outer side thereof to communicate with the high-pressure gas side to form an air inlet.

[0067] Specifically, the gas is introduced into the tooth-shaped boost groove 11 through the air inlet, and the high-pressure gas is accurately introduced into the tooth-shaped boost groove 11 through the air inlet to avoid turbulence.

[0068] Optionally, the groove bottom end of the tooth-shaped boost groove 11 extends along the axial inner side thereof to the sealing dam to form a groove root.

[0069] Specifically, the groove root extends to form a gradual channel, guiding the gas to diffuse smoothly, promoting uniform distribution of the air film, and improving the stiffness of the air film. By controlling the gas flow path, the thickness of the air film is made more stable, the isolation effect of the sealing surface is enhanced, and friction and wear are reduced. The groove root and the sealing dam cooperate to form a multi-stage throttling structure. When the gas flows through the groove root, a throttling effect is generated through the contraction and expansion of the channel, which reduces the gas pressure, effectively blocks the leakage path, and reduces the leakage of the medium. The groove root connects the toothed boost groove 11 and the sealing dam, optimizes the structural force distribution, reduces stress concentration, improves the deformation resistance of the sealing component, and extends the service life, especially under high pressure and high speed conditions to ensure the stability of the sealing system.

[0070] Optionally, the non-toothed characteristic groove area a constitutes the leeward side, and the toothed characteristic groove area b constitutes the windward side.

[0071] Specifically, the width of each tooth-shaped boost groove 11 constitutes a windward side and a leeward side toward the two side walls, wherein the windward side is the side of the tooth-shaped boost groove 11 having a tooth-shaped feature, the windward side is directly opposite to the inlet gas flowing into the tooth-shaped boost groove 11, and the leeward side is the side without tooth-shaped features. When the gas flows from the groove area a without tooth-shaped features into the groove area b with a certain speed, the gas increases the flow velocity and thus increases the dynamic pressure in order to maintain the conservation of flow rate when the cross-sectional area is reduced.

[0072] It should be noted that structures and / or installation methods not described in detail in this application are known to those skilled in the art in combination with common knowledge and / or prior art, and are not the focus of disclosure in this application and will not be further elaborated herein.

[0073] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solution of the present application rather than to limit it. Although the present application has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made in form and details without departing from the scope defined by the claims of the present application; the dimensions of the drawings are not related to the specific objects, and the dimensions of the objects can be changed arbitrarily.

Claims

1. A cylindrical air film sealing structure of a tooth-shaped boosting groove, comprising a floating ring (6), a dynamic ring (7) and a main shaft (8), wherein a layer of micrometer-level cylindrical air film is formed between the floating ring (6) and the dynamic ring (7), characterized in that: The cylindrical air film sealing structure of the tooth-shaped boosting groove also includes: A rear end cover (1) and a front end cover (10) mounted on the floating ring (6) and the moving ring (7); A plurality of tooth-shaped boosting grooves (11) are arranged in a circumferential array at equal intervals on the outer peripheral surface of the moving ring (7), each tooth-shaped boosting groove (11) comprising a non-tooth-shaped characteristic groove area a and a tooth-shaped characteristic groove area b; Among them, a tooth-shaped structure protruding into the groove is provided in the tooth-shaped characteristic groove area b, and the tooth-shaped structure forms a contraction channel along the gas flow direction, so that when the gas flows into the tooth-shaped characteristic groove area b through the non-tooth-shaped characteristic groove area a, the cross-sectional area of ​​the flow channel decreases along the gas flow direction.

2. The cylindrical air film sealing structure of the tooth-shaped boosting groove according to claim 1, characterized in that: A plurality of flexible goose-shaped support members (4) are provided between the floating ring (6) and the rear end cover (1).

3. The cylindrical air film sealing structure of the tooth-shaped boosting groove according to claim 2, characterized in that: The wing tip portion (12) of the flexible goose-shaped support member (4) has an arc shape that matches the outer periphery of the floating ring (6), and the radius of the arc shape is consistent with the radius of the outer periphery of the floating ring (6).

4. The cylindrical air film sealing structure of the tooth-shaped boosting groove according to claim 1 or 2, characterized in that: The floating ring (6) is connected to the front end cover (10) via a positioning pin (9), and the floating ring (6) is connected to the rear end cover (1) via a spring (5).

5. The cylindrical air film sealing structure of the tooth-shaped boosting groove according to claim 4, characterized in that: The rear end cover (1) and the front end cover (10) are connected via hexagon socket bolts (2), and a sealing ring (3) is provided at the connection between the two.

6. The cylindrical air film sealing structure of the tooth-shaped boosting groove according to claim 1, characterized in that: The side of the cylindrical air film close to the rear end cover (1) is the high-pressure gas side, and the side close to the front end cover (10) is the low-pressure gas side.

7. The cylindrical air film sealing structure of the tooth-shaped boosting groove according to claim 6, characterized in that: The cylindrical area between the adjacent tooth-shaped boost grooves (11) and the cylindrical area between the tooth-shaped boost grooves (11) and the low-pressure gas side form a sealing dam.

8. The cylindrical air film sealing structure of the tooth-shaped boosting groove according to claim 7, characterized in that: The slot end of the tooth-shaped supercharging slot (11) extends along its axial outer side to communicate with the high-pressure gas side to form an air inlet.

9. The cylindrical air film sealing structure of the tooth-shaped boosting groove according to claim 8, characterized in that: The groove bottom end of the tooth-shaped boost groove (11) extends along the axial inner side thereof to the sealing dam to form a groove root.

10. The cylindrical air film sealing structure of the tooth-shaped boosting groove according to claim 1, characterized in that: The non-toothed characteristic groove area a constitutes the leeward side, and the toothed characteristic groove area b constitutes the windward side.

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