Sealing comb tooth structure and sealing structure

Abstract

A sealing grate tooth structure is provided, which is arranged on a rotor member and is used to block a first space and a second space, and includes a plurality of circumferential grate tooth rings and a plurality of arc-shaped teeth. The sealing grate tooth structure is provided with the plurality of arc-shaped teeth on the axial outer side facing the first space or / and the second space. The arc-shaped teeth are arranged obliquely on the axial outer side. The tooth tops of the arc-shaped teeth are forward relative to the tooth roots along the rotation direction of the rotor. A groove-shaped flow channel is defined between adjacent arc-shaped teeth for sucking the airflow located at the tooth tops. The sealing grate tooth structure can improve the sealing effect. A sealing structure is also provided.

Description

Technical Field

[0001] The invention relates to the field of aviation engine sealing, and in particular to the field of sealing comb teeth. Background Art

[0002] With the development of aviation, the requirements for aircraft maneuverability, reliability and economy are getting higher and higher. Therefore, it is urgent to improve the various components of aircraft engines to ensure the high performance requirements of the engine. Low fuel consumption, high thrust-to-weight ratio, high reliability and durability are the development trends of modern aviation gas turbine engines. However, the internal temperature and pressure ratio of the engine are gradually increasing, making the leakage of the internal flow coefficient more and more serious, and the performance of the seal directly affects the fuel consumption rate, flight cost, thrust-to-weight ratio and other working performance of the aircraft engine. In order to reduce leakage losses and improve the overall performance of the engine, it is particularly important to improve the original sealing devices in many parts.

[0003] In order to ensure the sealing of the air path between the rotor and the stator, the most widely used sealing grate structure in current engines is a non-contact dynamic seal that uses the sudden expansion and contraction of the channel to increase the flow resistance to limit fluid leakage. The main function of the bearing cavity lubricating oil seal is to effectively isolate the bearing cavity of the engine rotor system from the airflow environment of the engine, protect the bearing and lubricating oil from damage to the airflow path, and prevent lubricating oil leakage. However, when the pressure difference between the bearing cavity and the outside of the bearing cavity is insufficient, a reverse pressure difference will appear at the seal, and the lubricating oil in the cavity will leak from the gap of the sealing channel and increase the air pressure outside the bearing cavity, which will also lead to an increase in air leakage and higher lubricating oil consumption, and even high-temperature and high-pressure gas will leak into the bearing cavity, increasing the risk of lubricating oil burning and coking in the bearing cavity. Summary of the invention

[0004] An object of the present invention is to provide a comb teeth sealing structure which can improve the sealing effect.

[0005] The sealing grate structure for achieving the above purpose is arranged on the rotor part, and is used to block the first space and the second space, and includes a plurality of circumferential grate rings and a plurality of arc-shaped teeth. The sealing grate structure is provided with the plurality of arc-shaped teeth on the axial outer side facing the first space or / and the second space, and the arc-shaped teeth are arranged obliquely on the axial outer side, and the tooth tops of the arc-shaped teeth are forward relative to the tooth roots along the rotation direction of the rotor, and a groove-shaped flow channel is defined between adjacent arc-shaped teeth, which is used to suck the airflow located at the tooth tops.

[0006] In one or more embodiments, the grooved flow channel is tapered from the tooth top to the tooth root.

[0007] In one or more embodiments, an inclination angle of the tooth root relative to the rotor member ranges from 20° to 60°.

[0008] In one or more embodiments, the arc-shaped teeth are symmetrically distributed toward the first space and the second space.

[0009] In one or more embodiments, the length of the arc-shaped teeth along the axial direction is 2 to 3 times the axial thickness of the circumferential comb ring.

[0010] Another object of the present invention is to provide a sealing structure, comprising a sealing ring arranged on a stator component and a sealing grate structure arranged on a rotor component, wherein the sealing grate structure is the above-mentioned sealing grate structure.

[0011] In one or more embodiments, the inner surface of the sealing ring includes an easy-to-wear coating or a honeycomb structure, and the circumferential grate ring of the sealing grate structure is perpendicular to the axial direction of the rotor member.

[0012] The above-mentioned comb teeth sealing structure is provided with arc-shaped teeth located on both sides of the axial direction. The arc-shaped groove surface of the arc-shaped teeth can guide the gas to flow from the tooth top to the tooth root during the rotation process, thereby forming a low-pressure area at the tooth top through suction, so that the front and rear pressure difference of the circumferential comb teeth ring is reduced, thereby reducing the gas leakage.

[0013] The radially extending arc-shaped teeth can guide the gas to spiral around the rotor in the direction away from the sealing grate structure, thereby forming a spiral airflow to resist the incoming flow, further enhancing the sealing effect of the grate structure. If the arc-shaped teeth face the inside of the oil chamber, the movement of the spiral airflow will help separate the lubricating oil from the oil and gas, further reducing the lubricating oil consumption and improving the safety of engine operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] 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:

[0015] Figure 1 This is a schematic diagram of a common aircraft engine bearing cavity;

[0016] Figure 2 Schematic diagram of an embodiment of a sealing grate tooth structure;

[0017] Figure 3 It is a schematic diagram of the airflow motion disturbed by the arc-shaped teeth;

[0018] Figure 4 It is a working principle diagram of an embodiment of a sealing comb tooth structure.

[0019] Description of Reference Numerals

[0020] 1 Bearing cavity

[0021] 2 Sealing structure

[0022] 3. First bearing

[0023] 4 Second bearing

[0024] 5 Rotor parts

[0025] 6 static components

[0026] 10 Bearing outer cavity

[0027] 11 Bearing cavity

[0028] 12 Compressed gas

[0029] 13 Oil and gas flow

[0030] 61 Sealing Ring

[0031] 50 Circumferential Comb Ring

[0032] 51 First circumferential comb ring

[0033] 52 Second circumferential comb ring

[0034] 53 Rotation direction

[0035] 54 Axis

[0036] 30 Curved teeth

[0037] 40 Second arc tooth

[0038] 100 First Space

[0039] 200 Second Space

[0040] 301 Tooth top

[0041] 302 Tooth root

[0042] 303 groove surface

[0043] 70 groove flow channel

[0044] 71 Incoming air flow

[0045] 72 Top Airflow

[0046] 74 First Spiral Airflow

[0047] 84 Second Spiral Airflow DETAILED DESCRIPTION

[0048] The present invention is further described below in conjunction with specific embodiments and 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 the description herein. 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 protection scope of the present invention should not be limited by the content of this specific embodiment.

[0049] It should be noted that these and other subsequent 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.

[0050] Reference Figure 1 As shown, the bearing cavity 1 formed between the rotors and stators of the aircraft engine is usually air-sealed by a sealing structure 2 to ensure that the lubricating oil used for lubrication and cooling of the first bearing 3 and the second bearing 4 does not leak.

[0051] During the operation of the engine, the lubricating oil in the inner cavity 11 of the bearing usually exists in the form of oil and gas. A part of the oil and gas 14 in the inner cavity 11 of the bearing enters the rotor part, and the outer cavity 10 of the bearing will lead a stream of compressed gas 12 with a certain pressure to block the oil and gas trying to leak out in the bearing cavity, thereby building up the pressure in the bearing cavity 11. In order to improve the sealing effect of the compressed gas 12 on the oil and gas and minimize the use of the compressed gas 12, a sealing structure is usually designed between the rotor part 5 and the stator part 6, and the common structure is a comb teeth sealing structure.

[0052] In the grate sealing structure, the rotor member 5 rotates around the axis 54 in the direction of rotation 53, and the sealing grate ring 50 provided on the rotor member 5 rotates accordingly, and maintains a certain gap with the sealing ring 61. The multiple circumferential grate rings 50 on the sealing grate and the sealing ring 61 define a sudden expansion and contraction channel, and utilize the flow contraction effect and throttling effect to increase the energy consumption of the airflow to achieve the purpose of sealing.

[0053] In one embodiment, the inner surface of the sealing ring 61 is usually designed as an easily wearable coating sealing ring 61 or a honeycomb structure, and there is a small gap between the circumferential comb ring 50 and the inner ring of the sealing ring 61, which is used to prevent the rotor and stator from rubbing against each other and reduce the circulation of air inside and outside the bearing cavity to achieve a sealing effect. However, if the pressure difference between the inner cavity 11 of the bearing and the outer cavity 10 of the bearing is insufficient, oil and gas are likely to leak through the gap, increasing the risk of engine operation.

[0054] The sealing comb tooth structure involved in the present disclosure refers to Figures 2 to 4 As shown, the sealing effect can be further improved, the high-temperature seal and oil gas in the lubricating oil chamber can be effectively blocked, and the demand for the compressor outlet bleed air volume can be reduced, thereby improving the engine operating efficiency.

[0055] Reference Figure 2 and Figure 3 As shown, the comb teeth sealing structure is arranged on the rotor member 5 to block the first space 100 and the second space 200. The first space 100 and the second space 200 in this embodiment are the bearing outer cavity 10 and the bearing inner cavity 11 in the above-mentioned bearing cavity lubricating oil sealing system. However, those skilled in the art should understand that the first space 100 and the second space 200 include but are not limited to the above-mentioned scenarios. In other embodiments, the first space 100 and the second space 200 can be other scenarios that need to be sealed in the aircraft engine.

[0056] The comb tooth sealing structure includes a plurality of circumferential comb tooth rings 50, for example Figure 2 As shown, the first circumferential grate ring 51 and the second circumferential grate ring 52 are distributed side by side in the axial direction. The plurality of circumferential grate rings 50 distributed circumferentially are used to form sudden expansion and contraction channels with the sealing ring 61 .

[0057] The comb teeth sealing structure also has multiple arcuate teeth 30 arranged on the axial outer side facing the first space 100 and / or the second space 200. The arcuate teeth 30 are arranged obliquely on the axial outer side, such as the arcuate teeth 30 arranged on the axial outer side of the first circumferential comb teeth ring 51 face the incoming flow direction from the first space 100.

[0058] The tooth tops 301 of the arc-shaped teeth 30 are located forward relative to the tooth roots 302 along the rotation direction of the rotor, and groove-shaped flow channels 70 are defined between adjacent arc-shaped teeth 30 for sucking airflow at the tooth tops 301 .

[0059] Specifically, refer to Figure 3 As shown, the rotation direction 53 of the rotor member 5 is clockwise, the arc-shaped teeth 30 are radially arranged on the axial side, and the position of the tooth top 301 relative to the tooth root 302 along the rotation direction of the rotor is in front of the tooth root 302.

[0060] It should be noted that the tooth root 302 of the first arc-shaped tooth 30 is close to the rotor member 5, and the tooth top 301 is close to the sealing ring 61. In one embodiment, the length of the arc-shaped tooth 30 in the axial direction is 2 to 3 times the axial thickness of the circumferential comb tooth ring 50. The arc-shaped tooth 30 with an appropriate width can effectively define the groove-shaped flow channel 70, avoid the deviation of the airflow during the suction process, and effectively ensure the flow rate of the suction airflow.

[0061] Driven by the engine rotor 5, the first arc-shaped tooth 30 can effectively use the arc-shaped groove surface 303 to guide the gas to flow from the tooth top 301 to the tooth root 302. A groove-shaped flow channel 70 is defined between adjacent arc-shaped teeth 30, and the groove-shaped flow channel 70 is used to draw air from the tooth top 301. When the rotor rotates, the peripheral airflow of the groove-shaped flow channel 70 flows rapidly, and the pressure is nearly uniform. When the peripheral airflow flows through the groove surface 303 of the arc-shaped tooth 30, it is guided by the groove surface 303, and the peripheral airflow is sucked into the groove-shaped flow channel 70 from the tooth top 301 and flows toward the tooth root 302.

[0062] The grooved flow channel 70 provides a good drainage channel for gas flow, and can orderly disturb and guide the airflow to move along the grooved flow channel 70. Therefore, the arc-shaped tooth 30 can guide the airflow to flow through the grooved flow channel 70 by using the arc-shaped groove surface 303 to suck the top airflow 72 located at the tooth top 302. Through the suction effect, the airflow at the tooth top 301 is effectively reduced, thereby forming a low pressure area T1 near the tooth top 301.

[0063] Reference Figure 4 As shown in the figure, the low pressure area T1 formed by the suction is located outside the first circumferential grate ring 51, and there is an original pressure area T2 in the cavity between the first circumferential grate ring 51 and the adjacent circumferential grate ring, so the pressure difference between the low pressure area T1 and the pressure area T2 will be significantly reduced. The reduced pressure difference reduces the driving force of the airflow, and further reduces the airflow through the sealing grate structure, thereby improving the sealing effect and effectively avoiding airflow leakage.

[0064] As described above, the sealing grate teeth can reduce the pressure difference between the inside and outside of the circumferential grate tooth ring 50 , thereby reducing the leakage of gas from the first space 100 to the second space 200 .

[0065] In addition, the arc-shaped teeth 30 radially extending and arranged on the axial outer side of the first circumferential comb ring 51 can change the airflow direction.

[0066] Reference Figure 4 As shown, during the operation of the engine, the incoming airflow 71 in the first space 100 flows in a direction parallel to the rotor member 5 and attempts to enter the second space 200 through the tooth tip gap. Part of the incoming airflow 71 is sucked by the arc-shaped teeth 30, forming a movement from the tooth tip 301 to the tooth root 302, and is discharged along the tooth root 302, thereby forming a first spiral airflow 74. Since the arc-shaped teeth 30 are arranged radially, the airflow can be guided to rotate with the engine, and the first spiral airflow 74 is formed under the rotation of the rotor member 5, rotating around the rotor member 5 and in a direction away from the sealing comb tooth structure.

[0067] The first spiral airflow 74 moves outward due to the kinetic energy given by the rotor member 5 and moves away from the direction of the arc-shaped teeth 30. The first spiral airflow 74 can resist the flow of the original airflow 71, thereby blocking the incoming airflow 71 outside. The incoming airflow 71 is blocked by the first spiral airflow 74 to form a gas flow cycle outside the sealing grate teeth, which also generates a certain amount of energy dissipation, thereby reducing the flow of the airflow flowing through the sealing grate tooth structure, so as to further enhance the sealing effect of the grate tooth structure.

[0068] When the first space 100 is the outer cavity 10 of the bearing, the reduced pressure difference between the inside and outside of the sealing comb structure and the formed spiral airflow can ensure the same or even better sealing effect under the premise of less air intake, thereby effectively reducing the compressor air intake volume used for sealing, improving the performance of the whole machine, and reducing the fuel consumption rate of the engine. Under the condition of the same fuel load, the aircraft range can be increased and the turbine inlet temperature can be reduced, thereby extending the service life of the turbine, extending the overhaul and scrapping cycle of the engine, and reducing costs.

[0069] Furthermore, the groove-shaped flow channel 70 is tapered from the tooth top 301 to the tooth root 302 to improve the suction effect of the airflow.

[0070] The arc-shaped groove surface of the arc-shaped tooth is used to guide the original axial airflow to flow through the groove surface to form a rotating airflow. The groove surface 303 determines the flow of the airflow from the tooth top 301 to the tooth root 302. The grooved flow channel 70 draws the original axial airflow at the tooth top, and the original axial airflow will flow through the comb tooth structure in the axial direction without the interference of the arc-shaped tooth.

[0071] Thereby, the arc-shaped teeth 30 and the groove-shaped flow channel 70 formed therewith draw in the axial airflow, thereby reducing the flow of the gas flowing through the comb tooth structure and reducing the front-rear pressure difference of the circumferential comb tooth ring, thereby achieving a better sealing effect.

[0072] In a preferred example, the acute angle formed by the line connecting the tooth root 302 to the tooth top 301 and the rotor member 5 is in the range of 20 to 60 degrees, which can ensure that the airflow can be effectively sucked into the slot-shaped flow channel 70. The acute angle range formed by the line connecting the tooth root 302 to the tooth top 301 and the rotor member 5 includes but is not limited to the above-mentioned embodiment, and the angle is specifically designed by the staff in this field according to the incoming flow rate and the size of the rotor member to achieve a better drainage effect.

[0073] exist Figure 2 In the illustrated embodiment, in addition to the arcuate teeth 30 provided on the axial outer side of the first circumferential comb ring 51 facing the first space 100 , second arcuate teeth 40 are provided on the axial outer side of the second circumferential comb ring 52 facing the second space 200 .

[0074] Continue to combine Figure 4, the second arc-shaped tooth 40 located on the other side of the axial direction is introduced. The following embodiments use the component numbers and some contents of the previous embodiments, wherein the same numbers are used to represent the same or similar components, and the description of the same technical contents is selectively omitted. The description of the omitted parts can refer to the previous embodiments, and will not be repeated here.

[0075] The plurality of second arc-shaped teeth 40 are disposed on the axial outer side of the second circumferential comb ring 52 and face the second space 200 .

[0076] In one embodiment, the second space 200 is a bearing inner cavity 11 containing a large amount of oil and gas. A grooved flow channel 70 is formed between adjacent second arc-shaped teeth 40. By utilizing the arc-shaped groove 303 of the second arc-shaped teeth 40, the grooved flow channel 70 can guide the oil and gas flow 13 located at the tooth top 301 to move along the grooved flow channel 70 from the tooth top 301 to the tooth root 302, thereby effectively sucking the oil and gas flow 13 located at the tooth top 301 of the second arc-shaped teeth 40 and forming a low-pressure area at the tooth top 301. As a result, the pressure difference formed by the low-pressure area and the original pressure area in the cavity between the second circumferential comb tooth ring 52 and the adjacent circumferential comb tooth ring is reduced, thereby reducing the gas leakage.

[0077] In addition, the second arc-shaped teeth 40 also guide part of the oil and gas flow 13 to form a spiral motion around the rotor member 5 at the tooth root 302, and flow in a direction away from the sealing comb tooth structure to form a second spiral airflow 84.

[0078] The second spiral airflow 84 changes the flow direction of the original oil and gas airflow 13 and resists the flow of the original oil and gas airflow 13, thereby blocking the original oil and gas airflow 13 outside the second circumferential comb ring 52. The original oil and gas airflow 13 is blocked by the second spiral airflow 84 to form a gas flow cycle outside the sealing comb structure, which will produce a certain amount of energy dissipation, thereby reducing the oil and gas airflow passing through the sealing comb structure and further blocking gas leakage.

[0079] The second spiral airflow 84 formed in the bearing inner cavity 11 can also throw out the lubricating oil in the oil gas by centrifugal force during the rotational motion, thereby separating the lubricating oil in the oil gas airflow 13 and further reducing the lubricating oil consumption.

[0080] The effective discharge of lubricating oil can significantly reduce the lubricating oil consumption in the bearing cavity, which 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 oil gas in the lubricating oil cavity can prevent the high temperature and high pressure gas from leaking into the bearing cavity and causing the lubricating oil to burn and coke in the bearing cavity.

[0081] In a preferred embodiment, the arc-shaped teeth facing the first space 100 and the second space 200 are symmetrically distributed. The symmetrically distributed arc-shaped teeth can ensure the same suction effect on both sides, so as to improve the coordination of airflow distribution on both sides, so that both sides of the comb teeth have a sealing effect, and enhance the sealing effect of the solution.

[0082] In combination with the above introduction to the sealing grate teeth, a sealing structure can also be understood. The sealing structure includes a sealing ring arranged on the stator component and a sealing grate tooth structure arranged on the rotor component.

[0083] In one embodiment, the inner surface of the sealing ring includes a wear-resistant coating or a honeycomb structure, and the circumferential grate ring of the circumferential grate structure is perpendicular to the axial direction of the rotor. The sealing ring cooperates with the vertically distributed circumferential grate ring. The sealing grate structure is the sealing grate structure mentioned above.

[0084] When running together with the rotor, the multiple arc-shaped teeth on both sides of the axial direction of the sealing grate ring can guide the airflow through the groove-shaped flow channel formed between the arc-shaped teeth, thereby sucking the airflow at the tooth top, forming a low-pressure area at the tooth top, and reducing the pressure difference before and after the circumferential grate teeth, thereby reducing the gas leakage.

[0085] When the gas flows from the tooth top to the tooth root, it will also make a spiral motion around the rotor around the tooth bottom, forming a spiral airflow, which will use the spiral airflow to push the airflow on both sides away from the sealing grate tooth structure, further blocking the leakage of gas. When the arc-shaped teeth face the side of the bearing cavity, the oil and gas movement effect of the spiral motion will help separate the lubricating oil from the oil and gas, further reduce the lubricating oil consumption, and improve the safety of engine operation.

[0086] Although the present invention is disclosed as above with reference to the 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.

[0087] For example, the number of sealing grate rings is not limited to the three shown in the drawings, and multiple sealing grate rings can be axially arranged according to actual conditions; for another example, the curvature and length of the arc-shaped teeth are determined according to the actual suction effect, and are not limited to the dimensions shown in the drawings; for another example, the first space and the second space are not limited to the bearing outer cavity and the bearing inner cavity in the bearing cavity lubricating oil sealing system.

[0088] Therefore, any modifications, equivalent changes and modifications made to the above embodiments based on 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 structure, arranged on the rotor member (5), for blocking the first space (100) and the second space (200), comprising a plurality of circumferential grate rings (50), It is characterized in that The sealing comb tooth structure also includes a plurality of arc-shaped teeth (30), including a groove surface (303) facing radially inward, The sealing comb tooth structure is provided with the plurality of arc-shaped teeth (30) on the axial outer side facing the first space (100) or / and the second space (200); the arc-shaped teeth (30) are arranged obliquely on the axial outer side; the tooth tops (301) of the arc-shaped teeth (30) are located forward relative to the tooth roots (302) along the rotation direction of the rotor component (5); and groove-shaped flow channels (70) are defined between adjacent arc-shaped teeth (30) for sucking airflow located at the tooth tops (301).

2. The sealing comb tooth structure according to claim 1, It is characterized in that The groove-shaped flow channel (70) is gradually tapered in a direction from the tooth top (301) to the tooth root (302).

3. The sealing comb tooth structure according to claim 1, It is characterized in that The acute angle formed by the line connecting the tooth root (302) to the tooth top (301) and the rotor component (5) is in the range of 20 to 60 degrees.

4. The sealing comb tooth structure according to claim 1, It is characterized in that The arc-shaped teeth arranged toward the first space (100) and the second space (200) are symmetrically distributed.

5. The sealing comb tooth structure according to claim 1, It is characterized in that The length of the arc-shaped teeth (300) along the axial direction is 2 to 3 times the axial thickness of the circumferential comb tooth ring (50).

6. A sealing structure, comprising a sealing ring (61) arranged on a stator (6) and a sealing grate structure arranged on a rotor (5), It is characterized in that The sealing comb tooth structure is the sealing comb tooth structure described in any one of claims 1 to 5 above.

7. The sealing structure according to claim 6, It is characterized in that The inner surface of the sealing ring (61) comprises an easy-to-wear coating or a honeycomb structure, and the circumferential grate ring (50) of the sealing grate structure is perpendicular to the axial direction of the rotor component (5).

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