Pressurizing labyrinth sealing structure and engine

Abstract

A pressurizing labyrinth sealing structure is arranged in an air channel formed between a stator and a rotor and comprises a pressurizing stage, the pressurizing stage comprises an air inlet cavity with the sectional area reduced in the air flow direction, and at least part of the wall body of the air inlet cavity is formed by centrifugal blades which protrude out of the surface of the rotor and are provided with pneumatic structures. The airflow is guided by the centrifugal blades to flow to the peripheral sides of the centrifugal blades in the radial direction. The supercharging labyrinth sealing structure can effectively improve the sealing performance of the aero-engine and improve the energy efficiency of the engine. The utility model further provides an engine.

Description

Technical Field

[0001] The utility model belongs to the field of aviation engines, and in particular relates to a supercharging grate tooth sealing structure and an engine. Background Art

[0002] With the rapid development of the aviation industry, the requirements for the performance of the sealing structure of aircraft engines are getting higher and higher. As the industry's requirements for the efficiency and economy of aircraft engines are becoming increasingly stringent, the leakage of the gas path between the stator and the rotor has become more and more significant in restricting the comprehensive performance of the engine. At present, the conventional grate sealing structure can no longer meet the sealing requirements of future high-efficiency aircraft engines. Some technical solutions adopt an axial flow supercharging structure, which forms a high-pressure area between the grate teeth by setting one or more stages of sealing grate teeth as axial flow supercharging blades, thereby limiting the leakage from the high-pressure stage to the low-pressure stage. However, the supercharging efficiency of the axial flow supercharging structure is limited, and the pressure formed is not enough to fully prevent leakage. If a multi-stage axial flow supercharging structure is set, the axially flowing gas will be blocked by the next stage of supercharging blades, reducing efficiency. Therefore, providing a more effective grate sealing structure has a high application value for improving engine efficiency. Utility Model Content

[0003] The purpose of the utility model is to provide a supercharging grate teeth sealing structure to improve the sealing performance of the engine. The utility model also provides an engine.

[0004] According to an embodiment of one aspect of the utility model, a boost grate sealing structure is provided, providing a stator and a rotor, wherein the stator surrounds the outside of the rotor, an air passage is formed between the stator and the rotor, and the boost grate sealing structure is arranged in the air passage, including a boost stage, wherein the boost stage includes an air intake cavity whose cross-sectional area decreases along the flow direction of the air flow, wherein the wall of the air intake cavity is at least partially formed by centrifugal blades protruding from the surface of the rotor, and an aerodynamic structure is formed on the surface of the centrifugal blades to allow the airflow flowing along the axial direction to flow radially to the outer peripheral side of the centrifugal blades under the guidance of the centrifugal blades.

[0005] The supercharging grate sealing structure adopts a centrifugal supercharging structure, and the single-stage supercharging structure can achieve a more effective supercharging effect, thereby improving the sealing effect between the engine stator and the rotor, reducing leakage, and improving engine efficiency.

[0006] Furthermore, in some embodiments, the stator and the rotor form an expansion cavity with an increased cross-sectional area downstream of the centrifugal blades. When the compressed airflow enters the expansion cavity, a vortex can be formed. When gas leaks from the high-pressure stage, the vortex can dissipate the kinetic energy of the leaked gas, further reducing leakage to the low-pressure stage.

[0007] Furthermore, in some embodiments, the expansion cavity is formed between the centrifugal blades and the comb teeth protruding from the surface of the rotor.

[0008] Furthermore, in some embodiments, a plurality of grate teeth protruding from the surface of the rotor are provided downstream of the centrifugal blades. The plurality of grate teeth can further improve the sealing effect.

[0009] Furthermore, in some embodiments, the stator is provided with a flange protruding toward the rotor upstream of the centrifugal blades, and the flange and the centrifugal blades together form the air inlet cavity.

[0010] Furthermore, in some embodiments, the rotor is provided with a raised air induction structure upstream of the centrifugal blades, and the air induction structure and the centrifugal blades together form the air inlet cavity. Providing the air induction structure on the rotor can reduce the difficulty of machining the stator structure and reduce the maintenance cost.

[0011] Furthermore, in some embodiments, the rotor is provided with axial flow booster blades upstream of the centrifugal blades. Providing axial flow booster blades upstream of the centrifugal blades can further increase the sealing pressure and improve the sealing effect.

[0012] Furthermore, in some embodiments, at least a portion of the inner wall of the stator facing the rotor is provided with a honeycomb structure.

[0013] According to another embodiment of the utility model, there is provided an engine, which adopts the supercharging grate sealing structure in any of the aforementioned embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of the cross-sectional structure of an aircraft engine bearing cavity in one embodiment;

[0015] Figure 2 It is a schematic diagram of the cross-sectional structure of the supercharging grate teeth sealing structure in one embodiment;

[0016] Figure 3 A schematic diagram of the cross-sectional structure of a centrifugal blade in an embodiment;

[0017] Figure 4 It is a schematic diagram of the cross-sectional structure of the pressurized grate teeth sealing structure in another embodiment;

[0018] Figure 5 It is a schematic diagram of the cross-sectional structure of the supercharging grate teeth sealing structure in another embodiment;

[0019] Figure 6 for Figure 5 Schematic diagram of the radial cross-section structure of area A in the middle.

[0020] The purpose of the above drawings is to provide a detailed description of the present invention so that those skilled in the art can understand the technical concept of the present invention, but it is not intended to limit the present invention. For the sake of simplicity, the above drawings only schematically depict structures related to the technical features of the present invention, and do not strictly depict the complete structure and all details in accordance with the actual proportion. DETAILED DESCRIPTION

[0021] The present invention will be further described in detail below through specific embodiments in conjunction with the accompanying drawings.

[0022] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The phrase appearing in various locations in the specification does not necessarily refer to the same embodiment, nor is it limited to mutually exclusive independent or alternative embodiments. Those skilled in the art should be able to understand that the embodiments herein may be combined with other embodiments without causing structural conflicts.

[0023] In the description of this article, unless otherwise clearly specified and limited, the technical terms "installed", "connected", "connected" and the like should be understood in a broad sense, which can be a movable connection, a fixed connection or an integral connection. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of this application can be understood according to specific circumstances.

[0024] In the description of this document, terms indicating orientation or positional relationships, such as "up", "down", "left", "right", "horizontal", "vertical", "height", "length", and "width", are intended to accurately describe the embodiments and simplify the description, but are not intended to limit the parts or structures involved to have a specific orientation, be installed or operate in a specific orientation, and should not be construed as a limitation on the embodiments in this document.

[0025] In the description herein, "plurality" means at least two.

[0026] An embodiment of one aspect of the utility model provides a booster comb teeth sealing structure.

[0027] like Figure 1As shown, in an aircraft engine, the bearing cavity 11 formed between the rotor 1a and the stator 1b is usually sealed with air to ensure that the lubricating oil that provides lubrication and cooling for the bearings 3 and 4 does not leak. During the operation of the engine, the lubricating oil in the bearing cavity 11 usually exists in the form of oil gas 13, and a stream of compressed gas 12 with a certain pressure needs to be introduced into the outside 10 of the bearing cavity to seal the oil gas 13 in the bearing cavity 11, thereby establishing the pressure in the bearing cavity 11. In order to improve the sealing effect of the compressed gas 12 on the oil gas 13 and reduce the use of the compressor 12, it is necessary to set a sealing structure 2 between the rotor component 5 and the stator component 6 to seal the airway formed between the rotor component 5 and the stator component 6.

[0028] The cross-sectional structure of the sealing structure 2 is as follows: Figure 2 As shown, a boosting stage is provided in the air passage formed between the rotor member 5 and the stator member 6. The boosting stage includes an air inlet cavity with a reduced cross-sectional area from the section 101 to the section 102 of the air passage. The inner wall of the rotor member 5 is provided with a protruding centrifugal blade 20. The surface of the centrifugal blade 20 has an aerodynamic structure 21. Referring to the flow direction of the compressed gas 12, the stator member 6 is provided with a flange 61 protruding toward the rotor member 5 upstream of the centrifugal blade 20. The flange 61 and the aerodynamic structure 21 jointly define the air inlet cavity. The vertical and axial cross-sectional structures of the centrifugal blade 20 are as shown in FIG. Figure 3 As shown, the pneumatic structure 21 is a generally radial curved surface. As the rotor 5 rotates in the direction of arrow 53, the compressed gas 12 is guided by the pneumatic structure 21 under the centrifugal action, and the flow direction changes from axial to radial, and flows radially to the outer peripheral side of the centrifugal blade 20. At the same time, due to the reduction of the cross section of the air inlet cavity, the compressed gas 12 is further compressed and the pressure increases. It should be understood that the radial direction here does not refer to the strict radial direction in the mathematical sense, and the air flow often has a certain circumferential velocity component.

[0029] In a preferred embodiment, if Figure 2 As shown, a expansion cavity 103 with an increased cross-sectional area is formed downstream of the centrifugal blade 20. The cross-sectional area of ​​the expansion cavity 103 is significantly larger than the minimum gap between the centrifugal blade 20 and the stator 6. After the compressed gas 12 enters the expansion cavity 103, a vortex is formed. While a high-pressure environment is formed in the expansion cavity 103, if oil and gas escape from the downstream chamber 104 and enter the expansion cavity 103, the vortex can quickly dissipate its energy, prevent oil and gas leakage, and further improve the sealing effect. In a further preferred embodiment, the expansion cavity 103 is formed between the centrifugal blade 20 and the comb teeth 22 of a conventional structure. The comb teeth 22 protrude from the surface of the rotor part 5 and are arranged downstream of the centrifugal blade 20. In some embodiments, multiple comb teeth 22 are arranged downstream of the centrifugal blade 20 to further improve the sealing effect.

[0030] The supercharging grate sealing structure can achieve a better sealing effect than using only conventional grate teeth, thereby effectively reducing the consumption of compressed gas 12 and reducing the efficiency loss caused by engine leakage. Centrifugal supercharging can produce a better supercharging effect than axial flow supercharging through single-stage supercharging, thereby increasing the pressure in the expansion chamber 103 and further reducing leakage.

[0031] In another embodiment, the cross-sectional structure of the sealing structure 2 is as follows: Figure 4 As shown, the rotor part 5 is formed with a raised air induction structure 33 upstream of the centrifugal blade 30, and the air induction structure 33 and the centrifugal blade 30 form an air inlet cavity 31 together, and the cross-sectional area of ​​the air inlet cavity 31 from the upstream 101 to the downstream 102 is reduced. With the high-speed rotation of the rotor part 5, the compressed gas 12 flows radially in the air inlet cavity 31 to the outer peripheral side of the centrifugal blade 30, and the pressure increases with the reduction of the cross-sectional area of ​​the air inlet cavity 31. After entering the expansion cavity 103 formed between the centrifugal blade 30 and the comb teeth 32, a vortex is formed and a high-pressure environment is generated, which prevents oil and gas leakage in the downstream chamber 104. This structure does not require the stator part 6 to be modified, and the air inlet cavity 31 is completely formed by the rotor part 5, which reduces the processing difficulty of the stator part 6. At the same time, only the rotor part 5 needs to be repaired and maintained, thereby reducing the maintenance and replacement costs of the sealing structure 2.

[0032] In another embodiment, the cross-sectional structure of the sealing structure 2 is as follows: Figure 5 As shown, the rotor 5 is provided with an axial flow booster blade 41 upstream of the centrifugal blade 40. The axial flow booster blade 41 firstly pressurizes the compressed gas 12 to further improve the boosting effect of the centrifugal blade 40, so that the pressure in the expansion cavity 103 is further increased, thereby forming a better sealing effect on the downstream chamber 104. The radial cross-sectional structure of the axial flow compression blade along the rotor 5 is as follows: Figure 6 As shown, after being pressurized by the axial flow supercharging blades 41 , the flow direction of the compressed gas 12 remains substantially unchanged along the axial direction of the rotor member 5 .

[0033] In a preferred embodiment, if Figure 2 As shown, the inner side surface of the stator component 6 opposite to the rotor component 5 is arranged as a honeycomb structure, so that the honeycomb structure cooperates with the centrifugal blades 20 and the comb teeth 22 to produce a better sealing effect.

[0034] Another embodiment of the utility model provides an engine, which adopts the supercharging grate sealing structure in any of the above embodiments.

[0035] The purpose of the above embodiments is to further explain the utility model in detail in conjunction with the accompanying drawings so that those skilled in the art can understand the technical concept of the utility model. Within the scope of the claims of the utility model, the optimization or equivalent replacement of the part structure involved, and the combination of the implementation methods in different embodiments without conflict of structure and principle, all fall within the protection scope of the utility model.

Claims

1. A supercharged grate seal structure, comprising a stator and a rotor, wherein the stator surrounds the outer side of the rotor, and an air passage is formed between the stator and the rotor, characterized in that: The boost comb sealing structure is arranged in the air duct, and includes a boost stage, wherein the boost stage includes an air intake cavity whose cross-sectional area decreases along the air flow direction, and the wall of the air intake cavity is at least partially formed by centrifugal blades protruding from the surface of the rotor, and the surface of the centrifugal blades is formed with an aerodynamic structure to allow the airflow flowing along the axial direction to flow radially to the outer peripheral side of the centrifugal blades under the guidance of the centrifugal blades.

2. The supercharging grate teeth sealing structure according to claim 1, characterized in that: The stator and the rotor form an expansion cavity with an increased cross-sectional area downstream of the centrifugal blades.

3. The supercharging grate teeth sealing structure according to claim 2, characterized in that: The expansion cavity is formed between the centrifugal blades and the comb teeth protruding from the surface of the rotor.

4. The supercharging comb teeth sealing structure according to claim 1 or 2, characterized in that: A plurality of grate teeth protruding from the surface of the rotor are arranged downstream of the centrifugal blades.

5. The supercharging comb teeth sealing structure according to claim 1 or 2, characterized in that: The stator is provided with a flange protruding toward the rotor upstream of the centrifugal blades, and the flange and the centrifugal blades together form the air inlet cavity.

6. The supercharging comb teeth sealing structure according to claim 1 or 2, characterized in that: The rotor is formed with a protruding air induction structure upstream of the centrifugal blades, and the air induction structure and the centrifugal blades together form the air inlet cavity.

7. The pressurized grate teeth sealing structure according to claim 1 or 2, characterized in that: The rotor is provided with axial flow supercharging blades upstream of the centrifugal blades.

8. The supercharging comb teeth sealing structure according to claim 1 or 2, characterized in that: At least a portion of the inner wall of the stator facing the rotor is provided with a honeycomb structure.

9. An engine, characterized in that: A pressurized comb tooth sealing structure as described in any one of claims 1 to 8 is adopted.

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