Sealing structure and sealing grate teeth

Abstract

The present invention provides a sealing grate, which is arranged in the circumferential gap between the rotor and the stator. The sealing grate includes circumferential grate, the tooth roots of which are arranged on the rotor or the stator, and the tooth tops face the stator or the rotor. The sealing grate also includes a plurality of side plates, which are circumferentially distributed on the side end faces of the circumferential grate facing the incoming flow and extend outward from the side end faces toward the incoming flow. The radially outer end of at least one of the plurality of side plates is provided with a plurality of tooth grooves distributed along the axial direction. The present invention also provides a sealing structure. The above-mentioned sealing grate and sealing structure can reduce leakage losses.

Description

Technical Field

[0001] The present invention relates to a sealing structure, in particular to a sealing comb tooth. Background Art

[0002] In recent years, the aviation industry has developed rapidly, and the requirements for the maneuverability, reliability and economy of aircraft have become increasingly higher. This urgently requires improvements to aircraft engines, including improvements to their various components, to ensure that aircraft engines can meet high performance requirements.

[0003] Modern aircraft engines, such as gas turbine engines, are developing towards low fuel consumption, high thrust-to-weight ratio, high reliability and durability. However, the gradual increase in the internal temperature and pressure ratio of aircraft engines will cause the leakage of the internal flow coefficient to become increasingly serious. Among them, the sealing performance can have a direct impact on the working performance of aircraft engines, such as fuel consumption rate, flight cost, thrust-to-weight ratio, etc. Many parts involve sealing structures. It is particularly important to improve the original sealing structure to reduce leakage losses and thus improve the overall performance of aircraft engines.

[0004] Therefore, it is necessary to provide a sealing structure that can reduce leakage losses. Summary of the invention

[0005] The object of the present invention is to provide a sealing structure which can reduce leakage losses.

[0006] Another object of the present invention is to provide a sealing grate which can form a sealing structure that reduces leakage losses.

[0007] The present invention provides a sealing grate, which is arranged in the circumferential gap between the rotor and the stator. The sealing grate comprises circumferential grate, the tooth root of the circumferential grate is arranged on the first side of the rotor and the stator, and the tooth top faces the second side of the rotor and the stator, and the sealing grate also comprises a plurality of side plates, the plurality of side plates are circumferentially distributed on the side end surface of the circumferential grate facing the incoming flow and extend outward from the side end surface toward the incoming flow, and the radially outer end of at least one of the plurality of side plates is provided with a plurality of tooth grooves distributed in the axial direction.

[0008] In one embodiment, two adjacent side plates among the plurality of side plates are each provided with the plurality of tooth grooves distributed at equal intervals; and the intervals between the tooth grooves of the two side plates are different from each other.

[0009] In one embodiment, two adjacent side plates among the plurality of side plates are each provided with the plurality of tooth grooves having the same cross-sectional shape; and the cross-sectional shapes of the tooth grooves of the two side plates are different from each other.

[0010] In one embodiment, the tooth roots of the circumferential comb teeth are arranged on the rotor; and the angle between the direction along which the multiple side plates extend outward and the tangent vector of the rotor's rotation direction at the corresponding position is an obtuse angle.

[0011] In one embodiment, the outwardly extending lengths of the plurality of side panels are the same.

[0012] In one embodiment, the side panels are in the form of flat plates.

[0013] In one embodiment, the slot length direction of the tooth slot is consistent with the tangent vector of the rotor's rotation direction at a corresponding position.

[0014] In one embodiment, the groove depth of the tooth groove is 1 / 20 to 1 / 10 of the tooth height of the circumferential comb teeth; the groove width of the tooth groove is 1 / 10-1 / 5 of the tooth top width of the circumferential comb teeth; and / or the spacing between the tooth grooves is 1 / 2-2 of the groove width of the tooth groove.

[0015] The present invention also provides a sealing structure, comprising at least two comb tooth structures distributed along the axial direction of the rotor, wherein the two outermost comb tooth structures of the at least two comb tooth structures are composed of the aforementioned sealing comb teeth, and the side plates of the two sealing comb teeth respectively constituting the two comb tooth structures are located on the outer sides of the circumferential comb teeth of the two sealing comb teeth.

[0016] In one embodiment, the side plates of the two sealing comb teeth correspond to each other in the circumferential direction.

[0017] The side plates of the sealing grate teeth extend outward toward the incoming flow, and the multiple tooth grooves distributed axially at the top side end thereof will cause part of the incoming flow flowing toward the top side end thereof to form many vortices, thereby increasing the dissipation of the kinetic energy of the gas, thereby preventing this part of the incoming flow from flowing through the sealing grate teeth and reducing leakage losses.

[0018] In the sealing structure, at least two grate structures are distributed along the axial direction of the rotor, and the two outermost grate structures in the axial direction are composed of the sealing grate teeth, thereby reducing leakage on either side of the sealing structure and further reducing leakage losses. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and other features, properties and advantages of the present invention will become more apparent through the following description in conjunction with the accompanying drawings and embodiments, in which:

[0020] Figure 1 This is a schematic diagram of the area near the bearing cavity inside an aircraft engine.

[0021] Figure 2 is a perspective view of an exemplary sealing structure according to the present invention, wherein a rotor and a stator are also shown.

[0022] Figure 3 yes Figure 2 A plan view of an exemplary sealing structure in which the rotor is shown but the stator is not shown.

[0023] Figure 4 yes Figure 2 A cross-sectional view of an exemplary sealing structure.

[0024] Figure 5 It is a schematic diagram of an exemplary sealing structure acting on incoming flow.

[0025] Figure 6 yes Figure 5 A local enlarged view of point A1 in the middle.

[0026] Fig. 7A , Figure 7B , Figure 7C and Fig.7D They are schematic diagrams of tooth grooves with different cross-sectional shapes. DETAILED DESCRIPTION

[0027] The present invention is further described below in conjunction with specific implementation methods and accompanying drawings. More details are elaborated in the following description to facilitate a full understanding of the present invention. However, the present invention can obviously be implemented in a variety of other ways different from this description. Those skilled in the art can make similar generalizations and deductions based on actual application situations without violating the connotation of the present invention. Therefore, the scope of protection of the present invention should not be limited by the content of this specific implementation method.

[0028] For example, a first feature described later in the specification as being formed above or on a second feature may include an embodiment in which the first feature and the second feature are formed by direct connection, and may also include an embodiment in which an additional feature is formed between the first feature and the second feature, so that the first feature and the second feature may not be directly connected. Further, when a first element is described as being connected or combined with a second element, the description includes an embodiment in which the first element and the second element are directly connected or combined with each other, and also includes an embodiment in which one or more other intervening elements are added to indirectly connect or combine the first element and the second element.

[0029] Figure 1 The relevant structure of the aircraft engine bearing cavity S1 is shown as an example. In the aircraft engine 200, a bearing cavity S1 is formed between the rotor and the stator, and is usually sealed with compressed air to ensure that the lubricating oil (also referred to as lubricating oil) used for lubrication and cooling of the bearings 501 and 502 does not leak. The main function of the lubricating oil seal in the bearing cavity S1 is to effectively isolate the bearing cavity S1 of the engine rotor system from the airflow environment of the engine, such as the outer cavity S2, to protect the bearings 501, 502, etc. and the lubricating oil from damage to the airflow path, and to prevent lubricating oil leakage.

[0030] During the operation of the aircraft engine 200, the lubricating oil in the bearing cavity S1 usually exists in the form of oil gas G2. A stream of compressed gas G1 with a certain pressure can be introduced from the outside of the bearing cavity S1, i.e., the outer cavity S2, to block the oil gas G2 trying to leak out in the bearing cavity S1 and build up the pressure in the bearing cavity S1.

[0031] In order to avoid the reverse pressure difference at the seal, which may cause the lubricating oil in the bearing cavity S1 to leak from the seal flow gap, the air pressure of the compressed gas G1 in the outer cavity S2 can be increased. However, this will lead to an increase in air leakage and higher lubricating oil consumption, and may even cause high-temperature and high-pressure gas to leak into the bearing cavity S1, increasing the risk of lubricating oil burning and coking in the bearing cavity S1.

[0032] Usually, a sealing structure 10' can be set between the rotor part 400 and the stator part 300 to improve the sealing effect of the compressed gas G1 on the oil and gas G2, and even reduce the use of the compressed gas G1. The current aircraft engines widely use a comb seal structure involving sealing comb teeth as the aforementioned sealing structure 10'. The comb seal structure increases the flow resistance by expanding and contracting the channel suddenly, thereby limiting fluid leakage and realizing non-contact dynamic sealing.

[0033] The exemplary structure of the sealing grate teeth 1 provided by the present invention is as follows: Figures 2 to 4 As shown, Figure 2 An exemplary three-dimensional structure of a sealing structure 10 including sealing comb teeth 1 is shown. Figure 3 An exemplary side view of a sealing structure 10 including sealing comb teeth 1 is shown. Figure 4 An exemplary cross-sectional configuration of the sealing structure 10 including the sealing comb teeth 1 cooperating with the rotor and the stator is shown.

[0034] Figures 2 to 4 In the figures, the sealing structure 10 is used as an example to illustrate the exemplary structure of the sealing grate teeth 1, and the sealing structure 10 includes two sealing grate teeth 1. Figure 3 In the figure, they are respectively the left sealing grate teeth 1a and the right sealing grate teeth 1b. When not distinguished in the text, they can be collectively referred to as the sealing grate teeth 1, and when described separately, a or b is added after the same reference numeral to distinguish them. Figures 2 to 4 The sealing grate teeth 1 are described by taking the sealing grate teeth 1a in FIG. 1 as an example.

[0035] It should be understood that the drawings are only examples and are not drawn to scale, and should not be used to limit the actual scope of protection required by the present invention.

[0036] Combination Figure 2 and Figure 3The sealing grate teeth 1 are arranged in the circumferential gap GA between the rotor 4 and the stator 3. In the illustrated embodiment, the stator 3 is a sealing ring, which may be a part of the stator component 300 of the aircraft engine 200, and the rotor 4 is a rotating shaft, which may be a part of the rotor component 400 of the aircraft engine 200. The sealing ring of the stator 3 is sleeved on the outer peripheral side of the rotating shaft of the rotor 4, and an annular circumferential gap GA is formed between the two. The circumferential gap GA may also be referred to as an annular chamber, or annular chamber for short.

[0037] It can be understood that the rotor 4 and the stator 3 can define an axial direction X0, a circumferential direction C0 and a radial direction R0, wherein the axial direction X0 is along the rotation center O1 of the rotor 4 (also Figure 1 The circumferential direction C0 is the direction around the rotation center O1 of the rotor 4, and the radial direction R0 refers to the direction from the radial inside to the radial outside.

[0038] The sealing comb teeth 1 include circumferential comb teeth 2. The tooth roots 24 of the circumferential comb teeth 2 can be arranged on the first side of the rotor 4 and the stator 3, and the tooth tops 23 face the second side of the rotor 4 and the stator 3. In other words, the tooth roots 24 of the circumferential comb teeth 2 can be arranged on the rotor 4 or the stator 3, extending toward the stator 3 or the rotor 4. In the illustrated embodiment, the tooth roots 24 of the circumferential comb teeth 2 are arranged on the rotor 4, that is, the aforementioned first side is the rotor 4. There is a small annular gap SG between the tooth tops 23 of the annular circumferential comb teeth 2 and the sealing ring serving as the stator 3. The inner wall surface of the sealing ring serving as the stator 3 can be provided with a non-wearable coating or honeycomb. This can not only prevent the rotor and the stator from rubbing against each other, but also reduce the circulation of fluids on both sides, such as the air inside and outside the aforementioned bearing cavity S1, to achieve a sealing effect.

[0039] It can be understood that the use of words such as "first" and "second" to limit features is only to facilitate the distinction between corresponding features. Unless otherwise stated, the above words have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0040] The sealing grate 1 further comprises a plurality of side plates 5. It can be understood that "plurality" means at least two, for example, three, four or five or more.

[0041] The plurality of side plates 5 are distributed along the circumferential direction C0 on the side end surface 21 of the circumferential comb teeth 2 facing the incoming flow F and extend outward from the side end surface 21 toward the incoming flow F. The incoming flow F can be considered as the intrusion fluid that the sealing comb teeth 1 want to prevent. In the illustrated embodiment, the plurality of side plates 5 can be evenly distributed along the circumferential direction C0.

[0042] The radially outer end 53 of at least one of the plurality of side plates 5 is provided with a plurality of tooth grooves 6 distributed along the axial direction X0. The radially outer end 53 of the side plate 5 is also the top end portion (hereinafter referred to as the top side) closer to the tooth top 23 than the tooth root 24 in the tooth height direction H1 (consistent with the radial direction R0) of the circumferential comb teeth 2. In the illustrated embodiment, the top end 53 of each of the plurality of side plates 5 can be provided with a plurality of tooth grooves 6 distributed along the axial direction X0. In the illustrated embodiment, the top end 53 of the side plate 5 can be roughly flush with the tooth top 53 of the circumferential comb teeth 2, and maintain a gap with the sealing ring as the stator 3 that is roughly the same as the gap size at the tooth top 23, together forming the aforementioned annular gap SG. In the illustrated embodiment, the radially inner end (also referred to as the bottom end) of the side plate 5 can be directly connected to, for example, welded to the rotor 4, that is, roughly flush with the tooth root 24 of the circumferential comb teeth 2. In one embodiment, the side plate 5 may extend along a portion of the tooth height of the circumferential comb teeth 2 instead of extending along the entire tooth height of the circumferential comb teeth 2 .

[0043] The side plates 5 of the sealing grate teeth 1 distributed along the circumferential direction C0 extend outward toward the incoming flow F, and thus have a certain size in the axial direction X0 or the flow path of the incoming flow F. The multiple tooth grooves 6 distributed along the axial direction at the top end 53 of the sealing grate teeth 1 will cause the flow channel between the top end 53 and the stator 3 to continuously expand and contract. Figures 2 to 4 When the arrow in the figure points to the sealing grate teeth 1, the top side incoming flow F2 directed to the annular gap SG will form a plurality of tooth tip vortices FT due to the continuously expanding flow channel formed by the tooth grooves 6 on the top side end 53 of the side plate 5. Figure 5 and Figure 6 In this way, the dissipation of the kinetic energy of the gas can be increased, and the top side flow F2 can be prevented from flowing through the sealing grate teeth 1 via the annular gap SG.

[0044] Research shows that in the future, improving the performance of aircraft engines may depend half on the improvement of sealing technology and the reduction of leakage. Therefore, it is very important and increasingly urgent to improve the sealing structure to enhance its sealing performance. The above-mentioned sealing grate teeth 1 can meet the requirements for high-performance sealing structures. The improved structure of the sealing grate teeth 1 has important practical value in reducing fuel consumption and improving engine efficiency.

[0045] In the illustrated embodiment, the side panel 5 can be in the form of a flat plate, that is, the side panel 5 is a straight plate with a predetermined thickness. In one embodiment, the side panel 5 can also be a flat plate of unequal thickness. In another embodiment, the side panel 5 can also be in the form of a curved plate such as an arc plate or a spherical plate.

[0046] It is understood that specific words are used herein to describe embodiments of the present invention, such as "one embodiment", "another embodiment", and / or "some embodiments" to refer to a certain feature, structure or characteristic associated with at least one embodiment of the present invention. Therefore, it should be emphasized and noted that "one embodiment" or "another embodiment" mentioned twice or more in different places in this specification does not necessarily refer to the same embodiment. In addition, certain features, structures or characteristics of one or more embodiments of the present invention may be appropriately combined.

[0047] In the illustrated embodiment, the angle α between the direction along which the side plate 5 extends outward (hereinafter referred to as the extension direction D1) and the tangent vector TR of the steering RT of the rotor 4 at the corresponding position is an obtuse angle. It can be understood that the specific direction of the steering RT at different positions is different, and each position is specifically manifested as a corresponding tangent vector TR. The figure also shows the angle β in the form of an acute angle between the extension direction D1 of the side plate 5 and the radial plane PR perpendicular to the axial direction X0, and the angle β is complementary to the angle α. The radial plane PR can also be considered as the extension plane of the sealing comb teeth 2. The side plate 5 shown in the figure is inclined relative to the extension plane of the sealing comb teeth 2, and can also be called an inclined tooth.

[0048] The side plate 5 has a windward side surface 51 on the windward side SU relative to the turning direction RT of the rotor 4. It can be understood that the side plate 5 has a windward side SU and a leeward side SD relative to the turning direction RT. Figure 3 In the axial plane shown, the turning RT is shown as downward, for example, the windward side SU is the lower side, and the leeward side SD is the upper side. In addition, it should be understood that the description of "windward side SU" and "leeward side SD" is only for expressing the orientation, and is not intended to limit the flow medium rotating around the rotor 4. The fluid can be liquid or gas, and the common fluid in the aircraft engine 100 is airflow.

[0049] The included angle α between the extension direction D1 of the side plate 5 and the turning direction RT of the rotor 4 is an obtuse angle, so that the root side incoming flow F1 of the incoming flow F that is aligned with the side plate 5 will be turned back when it hits the windward side surface 51 of the side plate 5, thereby forming a return flow F3. The turned back return flow F3 not only has a reverse velocity component toward the incoming flow F, but also has a velocity component along the turning direction RT (or its tangent vector TR), so that a reverse spiral flow Fs will eventually be formed relative to the rotor 4, as shown in FIG. Figure 5 The reverse spiral airflow Fs will resist the incoming flow F, so the root-side incoming flow F1 aligned with the side plate 5 within the size range along the tooth height direction H1 will generate energy dissipation, thereby further reducing the leakage.

[0050] In the illustrated embodiment, the plurality of tooth grooves 6 provided at the top end 53 of the side plate 5 may be distributed at equal intervals along the axial direction X0. In one embodiment, the plurality of tooth grooves 6 provided at the top end 53 of the side plate 5 may be distributed at equal intervals along the extension direction D1 thereof. In another embodiment, the plurality of tooth grooves 6 provided at the top end 53 of the side plate 5 may also be distributed at non-equal intervals, for example, in the axial direction X0, or in the extension direction D1 thereof.

[0051] In the illustrated embodiment, two adjacent side plates 5 among the plurality of side plates 5 may each be provided with a plurality of tooth grooves 6 distributed at equal intervals. That is, the two side plates 5 are adjacent in the circumferential direction C0, and the plurality of tooth grooves 6 provided at the top end 53 of each of the two side plates 5 are distributed at equal intervals, and the equal interval distribution may be equal intervals along the axial direction X0, or may be equal intervals along its extension direction D1. The spacing t6 of the tooth grooves 6 of the two side plates 5 may be different from each other. That is, each of the two side plates 5 has a spacing t6 (of the tooth grooves 6), and the two spacings t6 are not equal to each other. In the illustrated embodiment, each of the plurality of side plates 5 may each be provided with a plurality of tooth grooves 6 distributed at equal intervals, and the spacing t6 of the tooth grooves 6 of each side plate 5 may be different from each other.

[0052] The multiple side plates 5 divide the entire annular cavity formed by the circumferential gap GA between the rotor 4 and the stator 3 into multiple small chambers spaced apart in the circumferential direction C0, which can block the circumferential flow of the airflow before and after the sealing comb teeth 1, and the spacing t6 of the tooth grooves 6 at each top side end 53 is different, which can further enhance the formation of the tooth tip vortex FT, thereby improving the sealing effect of the sealing comb teeth 1.

[0053] In the illustrated embodiment, two adjacent side plates 5 among the plurality of side plates 5 are each provided with a plurality of tooth grooves 6 having the same cross-sectional shape. That is, the two side plates 5 are adjacent in the circumferential direction C0, and the cross-sectional shapes of the plurality of tooth grooves 6 provided at the top end 53 of each of the two side plates 5 are the same. However, the cross-sectional shapes of the tooth grooves 6 of the two side plates 5 may be different from each other. That is, each of the two side plates 5 has a cross-sectional shape (of the tooth groove 6), and the cross-sectional shapes of the two side plates 5 are different from each other. In the illustrated embodiment, each of the plurality of side plates 5 may be each provided with a plurality of tooth grooves 6 having the same cross-sectional shape, and each side plate 5 may be different from the tooth grooves 6 of the adjacent side plates 5 in cross-sectional shape.

[0054] For example, the cross-sectional shape of the tooth groove 6 can be a triangle, such as Fig. 7A As shown, it can also be a semi-ellipse, such as Figure 7B As shown, it can also be a rectangle, such as Figure 7C As shown, it can also be a semicircle, such as Fig.7D shown.

[0055] The different cross-sectional shapes of the tooth grooves 6 of the adjacent side plates 5 can also further enhance the formation of the tooth tip vortex FT, thereby improving the sealing effect of the sealing comb teeth 1.

[0056] The spacing t6 of the tooth grooves 6 can be, for example, the dimension between the groove bottoms of adjacent tooth grooves 6 in the extension direction D1. The tooth grooves 6 also have dimensions such as groove depth d6 and groove width w6. The groove depth d6 can be, for example, the dimension between the groove opening and the groove bottom of the tooth groove 6 in the tooth height direction H1. The groove width w6 can be, for example, the width dimension of the groove opening of the tooth groove 6 in the extension direction D1. In the illustrated embodiment, the groove depth d6 of the tooth groove 6 can be 1 / 20 to 1 / 10 of the tooth height h2 of the circumferential comb teeth 2. The groove width w6 of the tooth groove 6 can be 1 / 10-1 / 5 of the tooth top width w2 of the circumferential comb teeth 2. The spacing t6 of the tooth grooves 6 can be 1 / 2-2 of the groove width w6 of the tooth groove 6.

[0057] In the illustrated embodiment, the lengths of the multiple side panels 5 extending outwards may be the same, that is, the dimensions of the side panels 5 in the extension direction D1 are the same. This is not only convenient for manufacturing, but also allows the root-side incoming flow F1 to directly hit the outer end portion of the windward side surface 51 of each side panel 5 in the extension direction D1 without being blocked by the adjacent side panel 5, thus enhancing the return effect.

[0058] In the illustrated embodiment, the slot length direction of the tooth slot 6 (i.e., the direction in which the tooth slot 6 extends) may be consistent with the tangent vector TR of the direction RT of the rotor 4 at the corresponding position. In this way, the extending direction of the tooth slot 6 is perpendicular to the axial direction X0, and thus perpendicular to the flow direction of the incoming flow F, which has a better flow blocking effect on the incoming flow F.

[0059] The present invention further provides a sealing structure 10. The sealing structure 10 may include at least two comb tooth structures distributed along the axial direction X0 of the rotor 4. Figure 2 The two outermost grate teeth structures of the at least two grate teeth structures are composed of the sealing grate teeth 1, and the side plates 5 of the two sealing grate teeth 1 constituting the two grate teeth structures are located outside the circumferential grate teeth 2 of the two sealing grate teeth 1. Figure 3 In the embodiment, the sealing structure 10 includes not only the sealing grate teeth 1a and 1b as the two outermost grate tooth structures in the axial direction X0, but also an intermediate grate tooth structure 20. The intermediate grate tooth structure 20 may be a circumferential grate tooth similar to the circumferential grate teeth 2a of the sealing grate teeth 1a and the circumferential grate teeth 2b of the sealing grate teeth 1b. The circumferential grate teeth of the intermediate grate tooth structure 20 may be distributed at equal intervals with the circumferential grate teeth 2a and the circumferential grate teeth 2b in the axial direction X0.

[0060] Figures 2 to 5In the figure, similar reference numerals are used for the sealing grate teeth 1a and 1b. Specifically, the preceding reference numerals are the same but the suffixes are a and b, respectively, to indicate that the features belong to the sealing grate teeth 1a and 1b, respectively. It should be understood that similar reference numerals are used to represent similar features, and the description of the same technical content is selectively omitted and not repeated, so as to simplify the description. For example, the sealing grate teeth 1a and 1b can both be used as examples of the sealing grate teeth 1 and any description of the sealing grate teeth 1 above can be applied. For another example, the circumferential grate teeth 2a and 2b are examples of the circumferential grate teeth 2, the side plates 5a and 5b are examples of the side plates 5, and the incoming flows Fa and Fb are examples of the incoming flows F. The spiral airflows Fsa and Fsb are examples of the spiral airflow Fs, and so on.

[0061] In the sealing structure 10 , the side plates 5a and 5b of the two sealing comb teeth 1a and 1b may correspond to each other in the circumferential direction C0 . The sealing comb teeth 1a and 1b may be symmetrically distributed on both sides relative to the middle comb tooth structure 20 .

[0062] The sealing structure 10 can be used as Figure 1 The sealing structure 10' in the sealing structure 10. One of the two sealing grate teeth 1a and 1b of the sealing structure 10 can help prevent the compressed gas G1 outside the bearing cavity S1 from flowing from the outside of the bearing cavity S1 to the inside of the bearing cavity S1 via the sealing structure 10, while the other sealing grate tooth 1b of the two sealing grate teeth 1a and 1b can help prevent the oil gas G2 in the bearing cavity S1 from flowing from the inside of the bearing cavity S1 to the outside of the bearing cavity S1 via the sealing structure 10. That is, Figure 4 In the embodiment, the left side of the sealing structure 10 can be Figure 1 The compressed gas G1 in the right side, and the right side flow Fb can be Figure 1 Oil and gas G2.

[0063] In the above-mentioned aircraft engine 100, after the top side incoming flow F2 at the tooth tip gap enters the top side end 53 of the side plate 5 along the inner wall surface of the sealing ring of the stator 3, as shown in FIG. Figure 6 As shown, since the top side end 53 of the side plate 5 is designed with multiple tooth grooves 6 distributed along the axial direction X0, a plurality of tooth tip vortices FT are formed, thereby increasing the dissipation of the kinetic energy of the gas. At the same time, the annular cavity (that is, the circumferential gap SG) formed between the rotor and the stator may drive the gas to flow along the circumferential direction C0 and cause gas leakage, and the side plate 5 of the sealing comb teeth 1 of the present invention divides the annular cavity into a plurality of small chambers spaced apart in the circumferential direction C0, which can block the circumferential flow of the airflow before and after the sealing comb teeth 1. In particular, the spacing or cross-sectional shape of the tooth grooves 6 on the top side of each side plate 5 is different, which can further enhance the formation of the tooth tip vortex FT, thereby improving the sealing effect of the sealing comb teeth 1 and the sealing structure 10.

[0064] As the rotor 400 (i.e., the rotor 4) rotates along the turning direction RT, when the pressure outside the bearing cavity S1 is greater than the pressure inside the bearing cavity S1, the left side incoming flow Fa (compressed gas G1) of the sealing structure 10 will approach the sealing grate teeth 1a and try to enter the bearing cavity S1 through the tooth tip gap. However, the side plate 5a rotating with the rotor 400 will change the movement direction of the incoming flow F1a (compressed gas G1) within the grate tooth height range and move in the direction of the left side incoming flow F1a to become the return flow F3a. The return flow F3a moves outward (i.e., Figure 5 The spiral flow Fsa will be formed around the rotor 4 in the same direction as the turning RT and facing away from the sealing structure 10, while the reverse spiral flow Fsa will resist the invading flow Fa. Thus, the energy of the fluid flowing due to the pressure difference between the inside and outside of the bearing cavity S1 within the range of the comb tooth height is dissipated, and the leakage of the fluid into the bearing cavity S1 is reduced.

[0065] At the same time, when the pressure in the bearing cavity S1 is greater than the pressure outside the bearing cavity S1, the right side flow Fb (oil and gas G2) of the sealing structure 10 will approach the sealing grate teeth 1b and try to leak out of the bearing cavity S1. Similar to the above, the top side flow F2b (a part of the oil and gas G2) at the tooth tip gap will be blocked by the tooth tip vortex FT of the side plate 5b and cannot leak out, and the root side flow F1b (another part of the oil and gas G2) within the grate tooth height range will also be driven by the spiral flow Fsb to the direction away from the sealing structure 10 ( Figure 5 At the same time, the spiral flow Fsb (the aforementioned other part of the oil and gas G2) disturbed by the side plate 5 and in spiral motion will also be separated from the air due to the centrifugal force, thereby reducing the lubricating oil consumption caused by oil and gas leakage.

[0066] The above-mentioned sealing structure is achieved by designing a series of side plates on the outer sides of the two outermost circumferential comb teeth, and each side plate is provided with spaced tooth grooves on the top side, and the tooth grooves on the top sides of each side plate can be arranged differently, wherein the shapes and positions can be different. This can effectively disturb the airflow in the tooth top gaps on both sides of the circumferential comb teeth, forming vortices and strengthening the mixing of the inlet gas flow on both sides of the circumferential comb teeth, thereby enhancing kinetic energy dissipation and effectively reducing the leakage of the comb teeth.

[0067] Furthermore, the side plates form an angle with the circumferential comb teeth, and the angle direction is in line with the direction of the rotor. As the rotor rotates, the side plates on both sides can effectively push the gas at both ends away from the sealing structure and disturb the nearby air to form a spiral divergent airflow to form a sealing surface. The oil and gas disturbed by the side plates and spirally moving will also be separated from the air due to the centrifugal force, thereby reducing the lubricating oil consumption caused by oil and gas leakage.

[0068] When the above sealing structure is used for sealing the bearing cavity of an aircraft engine, the sealing effect can be improved at each speed stage, while reducing the demand for the compressor outlet bleed air, and the bearing cavity lubricating oil consumption can be reduced, and the high-temperature sealing gas and lubricating oil cavity oil gas can be blocked. When the compressor bleed air volume is reduced, the overall performance of the machine can be improved, the fuel consumption rate of the engine can be reduced, and the aircraft range can be increased under the same fuel load. The turbine inlet temperature can be reduced, thereby extending the service life of the turbine, extending the engine overhaul and scrapping cycle, and thus reducing costs. Reducing the bearing cavity lubricating oil consumption can improve the working performance of the bearing and ensure effective lubrication and cooling. At the same time, blocking the high-temperature seal and the lubricating oil cavity oil gas can prevent high-temperature and high-pressure gas from leaking into the bearing cavity, causing the lubricating oil to burn and coke in the bearing cavity.

[0069] Although the present invention is disclosed as above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, any modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope defined by the claims of the present invention.

Claims

1. A sealing grate, arranged in a circumferential gap between a rotor and a stator, comprising circumferential grate, wherein the tooth root of the circumferential grate is arranged on one of the rotor and the stator, and the tooth top faces the other of the rotor and the stator, characterized in that: The sealing comb teeth also include a plurality of side plates, which are circumferentially distributed on the side end surfaces of the circumferential comb teeth facing the invading fluid and extend outward from the side end surfaces toward the invading fluid, and a plurality of tooth grooves distributed along the axial direction are provided at the radially outer end of at least one side plate of the plurality of side plates.

2. The sealing grate teeth according to claim 1, characterized in that: Two adjacent side plates among the plurality of side plates are each provided with the plurality of tooth grooves distributed at equal intervals; The pitches of the tooth grooves of the two side plates are different from each other.

3. The sealing grate teeth according to claim 1, characterized in that: Two adjacent side plates among the plurality of side plates are each provided with the plurality of tooth grooves having the same cross-sectional shape; The cross-sectional shapes of the tooth grooves of the two side plates are different from each other.

4. The sealing grate teeth according to claim 1, characterized in that: The tooth roots of the circumferential comb teeth are arranged on the rotor; An angle between a direction along which the multiple side plates extend outward and a tangent vector of the rotor's rotation direction at a corresponding position is an obtuse angle.

5. The sealing grate teeth according to claim 1, characterized in that: The plurality of side panels have the same outwardly extending length.

6. The sealing grate teeth according to claim 1, characterized in that: The side panels are in the form of flat plates.

7. The sealing grate teeth according to claim 1, characterized in that: The slot length direction of the tooth slot is consistent with the tangent vector of the rotor's rotation direction at a corresponding position.

8. The sealing comb teeth according to claim 1, characterized in that: The groove depth of the tooth groove is 1 / 20 to 1 / 10 of the tooth height of the circumferential comb teeth; The groove width of the tooth groove is 1 / 10-1 / 5 of the tooth top width of the circumferential comb teeth; and / or The spacing of the tooth grooves is 1 / 2-2 of the groove width of the tooth grooves.

9. A sealing structure, comprising at least two grate structures distributed along the axial direction of a rotor, characterized in that: The two outermost comb tooth structures among the at least two comb tooth structures are composed of the sealing comb teeth according to any one of claims 1 to 8, and the side plates of the two sealing comb teeth respectively constituting the two comb tooth structures are located outside the circumferential comb teeth of the two sealing comb teeth.

10. The sealing structure according to claim 9, characterized in that: The side plates of the two sealing comb teeth correspond to each other in the circumferential direction.

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