Oil-gas two-phase end face foil sealing structure imitating sharkskin placoid scale

Abstract

The utility model discloses a sharkskin placoid scale imitating oil-gas two-phase end face foil sealing structure which comprises a movable ring and a static ring which are matched with each other, a bump foil and a flat foil are arranged on one side, facing the movable ring, of the static ring, and the bump foil is located between the flat foil and the static ring. A micro-texture is arranged on the surface of one side, facing the moving ring, of the flat foil. The utility model provides an oil-gas two-phase end face foil sealing structure imitating sharkskin placoid scales to solve the problems that in the prior art, a gas film sealing technology for an aero-engine is prone to abrasion and insufficient in stability, and the purposes of relieving the collision and abrasion situation and improving the universality and stability of the gas film sealing structure are achieved.

Description

Technical Field

[0001] The utility model relates to the field of air film sealing, in particular to an oil and gas two-phase end face foil sealing structure imitating shark skin shield scales. Background Art

[0002] As a complex and sophisticated system, the key components of aircraft engines need to be manufactured and assembled using special processes. A variety of seals are arranged in key parts of aerospace engines, such as bearing ends, blade tips, and airflow channels. The function of these seals is to effectively isolate the oil and gas in the cavity, control the reflux and leakage, thereby improving the operating efficiency of the unit and reducing operating costs. Since aircraft engines have extremely high requirements for sealing materials, complex structures, and special operating conditions, they must rely on modern manufacturing processes and methods to meet the requirements of harsh working conditions.

[0003] Advanced sealing technology is not only a key link in the development of aircraft engines, but also a decisive factor in ensuring that aircraft engines can operate efficiently and reliably. Due to special working conditions and harsh climates, aircraft engines place high demands on seals. In order to ensure that aircraft engines can operate stably for a long time at ultra-high rotation speeds, extremely high ambient temperatures and in a variety of postures, it is necessary to ensure that the sealing performance of aircraft engines when used in extreme environments has extremely high safety; however, the air film sealing technology used in aircraft engines in the existing technology still has defects such as easy wear and frequent maintenance, and there is still room for improvement in sealing stability. Utility Model Content

[0004] The utility model provides an oil-gas two-phase end face foil sealing structure imitating shark skin scales, so as to solve the problem that the air film sealing technology used for aircraft engines in the prior art is easy to wear and has insufficient stability, thereby alleviating the collision and wear and improving the universality and stability of the air film sealing structure.

[0005] The utility model is realized by the following technical solutions:

[0006] A shark skin-like shield scale-like oil-gas two-phase end face foil sealing structure comprises a dynamic ring and a static ring which match each other. A corrugated foil and a flat foil are arranged on the side of the static ring facing the dynamic ring, and the corrugated foil is located between the flat foil and the static ring. A micro-texture is arranged on the surface of the flat foil facing the dynamic ring.

[0007] In view of the problem that the air film sealing technology used in aircraft engines in the prior art is easy to wear and lacks stability, the utility model proposes an oil-gas two-phase end face foil sealing structure that imitates shark skin scales, wherein the dynamic ring and the static ring are both prior art in the field of air film sealing technology, which will not be elaborated here. The present application arranges a corrugated foil and a flat foil on the surface of the static ring, wherein the corrugated foil is located between the flat foil and the static ring, so that the flat foil faces the dynamic ring, and the gap between the flat foil and the dynamic ring constitutes the sealing gap of the air film seal; a plurality of micro textures are also arranged on the surface of the flat foil on one side facing the direction of the dynamic ring.

[0008] The present application forms a flexible end face gas-liquid two-phase contact seal by setting a corrugated foil and a flat foil, and makes up for the deficiencies of a traditional rigid end face mechanical seal by means of the flexible end face gas-liquid two-phase seal, thereby ensuring a nearly zero leakage sealing effect and shaft system under the high parameter use environment in the field of aero-engines, thereby significantly improving the universality and stability of the sealing structure, and ensuring the power stability of the engine, which is conducive to the wider application of gas-liquid two-phase air film seals in multiple fields such as petrochemicals, nuclear power and thermal power, aerospace, and deep-sea platforms.

[0009] The specific form of the micro-texture is not specifically limited here, and any micro-texture form that can be achieved by those skilled in the art can be used in this application.

[0010] Furthermore, the micro texture includes a plurality of shield scale groups evenly distributed in an annular manner, and each shield scale group includes a plurality of micro texture units. In this solution, a plurality of shield scale groups are distributed in an annular manner on the surface of the flat foil, so that a large number of micro texture units are also distributed 360° around the circumference. This distribution form effectively avoids the problem that the micro texture in the divergent area will damage the pressure bearing area, thereby causing the load-bearing capacity to decrease, and achieves a good balance in reducing friction and ensuring load-bearing capacity.

[0011] Furthermore, the micro-texture unit includes a number of radially distributed ribs; that is, in each shield scale group, there are a number of micro-texture units, and in each micro-texture unit, there are a number of ribs distributed radially; this structure can form a directional airflow channel between adjacent ribs, and the medium can enhance heat exchange when flowing through, and take away part of the heat generated by the end face seal during operation, thereby enhancing the heat dissipation effect; at the same time, this scheme can generate secondary vortices near the ribs, weaken the movement intensity of the flow vortex in the boundary layer, so that the low-speed fluid remains in the groove of the ribs, which has the beneficial effect of reducing friction resistance.

[0012] Furthermore, the major axis of the rib is perpendicular to the line between the center point of the rib and the center of the flat foil.

[0013] This solution clearly defines the extension direction of the ribs, so that the gaps of the micro-textures are consistent with the radial flow direction in the radial direction, and the distribution of the micro-textures in the circumferential direction is consistent with the circumferential direction. This arrangement is conducive to the stable flow of the medium.

[0014] Furthermore, the number of ribs in each microtexture unit is N, N is an odd number and N ≥ 3;

[0015] In the micro-texture unit, the long axis of the rib located in the middle is used as the symmetry axis, and the other ribs are symmetrically distributed compared with the rib located in the middle.

[0016] In this solution, there are at least three ribs in the micro-texture unit and the total number is an odd number, so there must be one rib located in the middle, with the long axis of the middle rib as the symmetry axis, and the remaining ribs are symmetrically distributed on both sides of the radial direction.

[0017] Furthermore, in the micro-texture unit, the length gradually decreases or increases from the ribs at the two radial ends to the ribs in the middle.

[0018] In this scheme, the lengths of two adjacent ribs in a micro-texture unit are different; for all ribs in the micro-texture unit, their lengths increase first and then decrease, or decrease first and then increase. This arrangement is more effective in reducing friction than common texture forms such as cylindrical pit texture and ball pit texture. In addition, the rib arrangement of this scheme also has the effect of reducing oil stains under oil-gas two-phase working conditions.

[0019] Furthermore, in the micro-texture unit, the lengths from the ribs at the two radial ends to the ribs in the middle are distributed in an arithmetic progression, which is beneficial to ensure the stability of the air film's bearing capacity.

[0020] Furthermore, the ribs between two adjacent shield scale groups correspond one to one in the circumferential direction and have complementary lengths.

[0021] Among them, one-to-one correspondence in the circumferential direction means one-to-one correspondence along the circumferential direction, which can ensure a continuous and stable airflow channel in the circumferential direction. The length complementarity means: the longest rib in one shield scale group is opposite to the shortest rib in another shield scale group in the circumferential direction; the second longest rib in one shield scale group is opposite to the second shortest rib in another shield scale group in the circumferential direction; and so on, so that the length of the ribs between two adjacent shield scale groups is in a state of increase and decrease. This structure is conducive to ensuring the stability of the air film bearing capacity, thereby further improving the sealing stability.

[0022] Furthermore, along the axial direction of the flat foil, the height of the rib is 1 / 3d to 1 / 2d, wherein d is the distance between the flat foil and the moving ring.

[0023] During the design process, the inventor of this case discovered that the friction during air film flow first decreases and then increases with the depth of the texture, which indicates that there is an optimal texture depth that minimizes the friction. After extensive research, it was concluded that the best drag reduction effect is achieved when the rib height is 1 / 3d to 1 / 2d.

[0024] Furthermore, along the radial direction of the flat foil, the distance between two adjacent ribs is d, wherein d is the distance between the flat foil and the moving ring. This solution is more conducive to generating secondary vortices near the ribs, and can further increase convective heat transfer and enhance the heat exchange effect.

[0025] Compared with the prior art, the utility model has the following advantages and beneficial effects:

[0026] 1. The utility model discloses an oil-gas two-phase end face foil sealing structure imitating shark skin scales, which forms a flexible end face gas-liquid two-phase contact seal by setting a corrugated foil and a flat foil. The flexible end face gas-liquid two-phase seal makes up for the deficiencies of the traditional rigid end face mechanical seal, ensures a nearly zero leakage sealing effect and shaft system under the high parameter use environment in the field of aviation engines, and thus significantly improves the universality and stability of the sealing structure, ensures the engine power stability, which is conducive to the gas-liquid two-phase air film seal to be more widely used in multiple fields such as petrochemical, nuclear power and thermal power, aerospace, and deep-sea platforms.

[0027] 2. The utility model provides an oil-gas two-phase end face foil sealing structure imitating shark skin scales, which can form a directional airflow channel between adjacent ribs. When the medium flows through, it can enhance heat exchange and take away part of the heat generated by the end face seal during operation, thereby enhancing the heat dissipation effect.

[0028] 3. The utility model has an oil-gas two-phase end face foil sealing structure imitating shark skin scales, which can generate secondary vortices near the inter-ribs of the ribs, weaken the motion intensity of the flow vortex in the boundary layer, keep the low-speed fluid in the groove of the ribs, and has the beneficial effect of reducing friction resistance.

[0029] 4. The utility model provides an oil-gas two-phase end face foil sealing structure imitating shark skin scales, which can enhance heat exchange and reduce oil adhesion while reducing the friction of the seal during operation, which is beneficial to the outflow of heat generated during the operation, ensures sealing performance, and reduces the risk of sealing failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings described herein are used to provide a further understanding of the embodiments of the present utility model, constitute a part of this application, and do not constitute a limitation of the embodiments of the present utility model. In the drawings:

[0031] Figure 1It is an exploded schematic diagram of a specific embodiment of the utility model;

[0032] Figure 2 It is a structural schematic diagram of a static ring in a specific embodiment of the utility model;

[0033] Figure 3 This is a schematic diagram of the structure of the wave foil in a specific embodiment of the utility model;

[0034] Figure 4 This is a schematic diagram of the structure of a flat foil in a specific embodiment of the utility model;

[0035] Figure 5 It is a partial schematic diagram of the micro-texture in a specific embodiment of the utility model.

[0036] Marks and corresponding parts names in the attached drawings:

[0037] 1-dynamic ring, 2-static ring, 3-corrugated foil, 4-flat foil, 5-first rib, 6-second rib, 7-third rib, 8-fourth rib. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical scheme and advantages of the utility model clearer, the utility model is further described in detail in combination with the embodiments and the accompanying drawings. The schematic implementation mode of the utility model and its description are only used to explain the utility model and are not used as a limitation of the utility model. In the description of the present application, it should be understood that the orientation or position relationship indicated by terms such as "front", "rear", "left", "right", "up", "down", "vertical", "horizontal", "high", "low", "inside", "outside", etc. is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the scope of protection of the present application.

[0039] Embodiment 1:

[0040] like Figures 1 to 4 The oil-gas two-phase end face foil sealing structure shown in the figure is imitating shark skin scales, comprising a dynamic ring 1 and a static ring 2 that match each other, wherein a corrugated foil 3 and a flat foil 4 are arranged on the side of the static ring 2 facing the direction of the dynamic ring 1, and the corrugated foil 3 is located between the flat foil 4 and the static ring 2; and a micro-texture is arranged on the surface of the flat foil 4 facing the direction of the dynamic ring 1.

[0041] In this embodiment, an annular boss is arranged on the end surface of the stationary ring 2, and the corrugated foil 3 and the flat foil 4 are both fixedly sleeved outside the annular boss.

[0042] This embodiment constitutes the entire end face foil sealing structure. During operation, due to the pressure difference between the inner and outer diameters, and the pressure at the outer diameter is greater than the pressure at the inner diameter, the oil and gas two-phase medium enters from the outer diameter and flows out from the inner diameter due to the pressure difference.

[0043] Embodiment 2:

[0044] A shark skin-like shield scale oil-gas two-phase end face foil sealing structure, based on Example 1, as Figures 1 to 5 As shown, the micro texture includes a plurality of shield scale groups evenly distributed in annular shapes, each of which includes a plurality of micro texture units; the micro texture unit includes a plurality of radially distributed ribs. The long axis of the rib is perpendicular to the line between the center point of the rib and the center of the flat foil 4.

[0045] In each microtexture unit, the number of ribs is N, N is an odd number and N ≥ 3;

[0046] In each micro-texture unit, the long axis of the middle rib is taken as the symmetry axis, and the other ribs are symmetrically distributed compared with the middle rib; and the length gradually decreases or increases from the ribs at the radial ends to the ribs in the middle.

[0047] The ribs between two adjacent shield scale groups correspond one to one in the circumferential direction and have complementary lengths.

[0048] More preferably, in the micro-texture unit, the lengths from the ribs at the two radial ends to the ribs in the middle are distributed in an arithmetic progression.

[0049] More preferably, the micro-texture units adjacent to each other in the radial direction share a rib.

[0050] like Figure 5 As shown, there are four ribs of different lengths in each micro-texture unit, which are defined as the first rib 5, the second rib 6, the third rib 7, and the fourth rib 8 from long to short, and their lengths are 6.3 mm, 4.8 mm, 3.3 mm, and 1.8 mm, respectively. The radial width of each rib is 0.5 mm. With the fourth rib 8 as the axis of symmetry, the third rib 7, the second rib 6, and the first rib 5 are distributed on both sides of the fourth rib 8 in the radial direction.

[0051] In the radial direction, the center distance between adjacent ribs is 0.95 mm; in the circumferential direction, the center distance between adjacent ribs is 1.6 mm, and the rib height is 5 um.

[0052] This embodiment has the following advantages:

[0053] While reducing the friction of the seal when it is working, it can enhance heat exchange and reduce oil adhesion, which is beneficial to the outflow of heat generated during the working process, ensuring sealing performance and avoiding seal failure; when working, the fluid generates secondary vortices near the ribs, so that the low-speed fluid remains in the grooves of the ribs, which can increase convective heat transfer and achieve the effect of enhancing heat exchange.

[0054] In addition, the micro-texture of this embodiment is fully distributed on the surface of the flat foil, which can enable the air film to form some tiny pressure areas before it ruptures, thereby offsetting part of the bearing capacity, avoiding a significant decrease in the bearing capacity of the air film due to the texture being located in the air film divergence domain, and being able to strike a balance between reducing friction and the bearing capacity of the air film; it ensures both the reduction of friction and the bearing capacity of the air film.

[0055] Embodiment 3:

[0056] An oil-gas two-phase end face foil sealing structure imitating shark skin scales. Different from Example 2, in this embodiment, the radial width of each rib is set to R; along the radial direction, the center distance between adjacent ribs is 2R; along the circumferential direction, the center distance between adjacent ribs is 3R.

[0057] Along the axial direction of the flat foil, the height of the rib is 1 / 3d to 1 / 2d, wherein d is the distance between the flat foil and the moving ring.

[0058] This embodiment is conducive to obtaining a more realistic micro-texture of shark skin shield scales, which can reduce the attachment of pollutants. The grooves on the surface of the shield scales reduce the actual contact area between the pollutants and the surface, forming a dynamic effect of water flow, generating tiny vortices, and helping to wash away surface particles and microorganisms. In addition, the geometric shape of the shield scales reduces adhesion, further reducing the attachment of pollutants. At the same time, compared with other textures such as cylindrical pit textures and ball pit textures, at the same texture depth, the shark skin shield scale texture has a good effect in reducing friction.

[0059] The specific implementation methods described above further illustrate the purpose, technical solutions and beneficial effects of the utility model in detail. It should be understood that the above description is only the specific implementation method of the utility model and is not used to limit the protection scope of the utility model. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the utility model should be included in the protection scope of the utility model.

[0060] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In addition, the term "connected" used in this article can be directly connected or indirectly connected via other components without special explanation.

Claims

1. An oil-gas two-phase end face foil sealing structure imitating shark skin scales, comprising a dynamic ring (1) and a static ring (2) matching each other, characterized in that: A corrugated foil (3) and a flat foil (4) are arranged on the side of the stationary ring (2) facing the direction where the dynamic ring (1) is located, and the corrugated foil (3) is located between the flat foil (4) and the stationary ring (2); and a micro-texture is arranged on the surface of the side of the flat foil (4) facing the direction where the dynamic ring (1) is located.

2. The oil-gas two-phase end face foil sealing structure imitating shark skin scales according to claim 1, characterized in that: The micro-texture includes a plurality of shield scale groups evenly distributed in an annular shape, and each shield scale group includes a plurality of micro-texture units.

3. The oil-gas two-phase end face foil sealing structure imitating shark skin scales according to claim 2, characterized in that: The micro-texture unit includes a plurality of radially distributed ribs.

4. The oil-gas two-phase end face foil sealing structure imitating shark skin scales according to claim 3, characterized in that: The long axis of the rib is perpendicular to the line between the center point of the rib and the center of the flat foil (4).

5. The oil-gas two-phase end face foil sealing structure imitating shark skin scales according to claim 3, characterized in that: The number of ribs in each microtexture unit is N, N is an odd number and N ≥ 3; In the micro-texture unit, the long axis of the rib located in the middle is used as the symmetry axis, and the other ribs are symmetrically distributed compared with the rib located in the middle.

6. The oil-gas two-phase end face foil sealing structure imitating shark skin scales according to claim 5, characterized in that: In the micro-texture unit, the length gradually decreases or increases from the ribs located at the two radial ends to the ribs located in the middle.

7. The oil-gas two-phase end face foil sealing structure imitating shark skin scales according to claim 5, characterized in that: In the micro-texture unit, the lengths from the ribs at the two radial ends to the ribs in the middle are distributed in an arithmetic progression.

8. The shark skin scale-like oil-gas two-phase end face foil sealing structure according to claim 3, characterized in that: The ribs between two adjacent shield scale groups correspond one to one in the circumferential direction and have complementary lengths.

9. The oil-gas two-phase end face foil sealing structure imitating shark skin scales according to any one of claims 3 to 8, characterized in that: Along the axial direction of the flat foil (4), the height of the ribs is 1 / 3d to 1 / 2d, wherein d is the distance between the flat foil (4) and the moving ring (1).

10. The oil-gas two-phase end face foil sealing structure imitating shark skin scales according to any one of claims 3 to 8, characterized in that: Along the radial direction of the flat foil (4), the distance between two adjacent ribs is d; wherein d is the distance between the flat foil (4) and the moving ring (1).

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