Baffle seal structure, sealing method, and aeroengine

Abstract

The application provides a labyrinth seal structure, a sealing method and an aero-engine. The labyrinth seal structure comprises: a rotor part comprising a first thin-walled part extending from an engine rotor, a labyrinth being arranged on a radial outer wall of the first thin-walled part; and a stator part comprising a second thin-walled part extending from an engine stator, a radial inner wall of the second thin-walled part being provided with a sealing part corresponding to the labyrinth; wherein the extension length of the first thin-walled part is greater than the extension length of the second thin-walled part; and a flow resistance element is arranged on the radial inner wall of the first thin-walled part, the blocking direction of the flow resistance element being: blocking the flow of the gas flowing from the side of the engine rotor to the labyrinth seal structure in the direction of the labyrinth seal structure after passing through the labyrinth seal structure, so as to flow along the radial inner wall of the first thin-walled part on the side of the radial inner wall of the first thin-walled part.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of aero-engines, in particular to a labyrinth seal structure, a sealing method and an aero-engine. BACKGROUND

[0002] In the field of aero-engine design, the form of labyrinth seal is widely used. For example, the labyrinth seal arranged at the connection between the engine inter-stage casing and the low-pressure turbine rotor. The part connected with one side of the stator is generally a sealing member, and the labyrinth rotor side connected with one side of the rotor is generally connected with the low-pressure turbine rotating shaft.

[0003] The key problems in the design of the labyrinth seal include ensuring that the labyrinth gap is within the design range. Too large or too small gap will have adverse effects on the engine, for example, too large gap will lose the sealing effect, and too small gap will cause scratching and produce adverse effects.

[0004] Under steady-state conditions, the labyrinth gap can be ensured to match the gap between the rotor and the stator at each operating condition by designing an appropriate initial gap value.

[0005] However, when the engine is in transient variation process of increasing or decreasing rotation, due to the inconsistent thermal response between the rotor and the stator, the deformation of the rotor and the stator on both sides of the labyrinth is not coordinated, which will cause the labyrinth gap to fluctuate in a large range, and the collision or the large gap will occur, which will have a significant harm to the performance and even the safety of the engine. SUMMARY

[0006] An object of the present application is to provide a labyrinth seal structure, by arranging a flow resistance element, the heat capacity of the rotor side is increased, and the heat transfer intensity of the rotor side is also reduced, the thermal response rate of the rotor is effectively slowed down, so as to improve the transient gap matching between the rotor and the stator, and the change of the labyrinth gap of the labyrinth seal structure during the operation of the engine meets the requirement of the safety of the engine.

[0007] According to a first aspect of the present application, the labyrinth seal structure comprises:

[0008] a rotor part comprising a first thin-walled member extending from an engine rotor, and a labyrinth is arranged on the radial outer wall of the first thin-walled member;

[0009] a stator part comprising a second thin-walled member extending from an engine stator, and a sealing member corresponding to the labyrinth is arranged on the radial inner wall of the second thin-walled member;

[0010] The extending length of the first thin-wall member is greater than the extending length of the second thin-wall member; the radial inner wall of the first thin-wall member is provided with a flow blocking element, and the blocking direction of the flow blocking element is that the airflow blocked by the flow blocking element after passing through the labyrinth sealing structure from the direction of the airflow flowing from the engine rotor side to the labyrinth sealing structure along the radial inner wall of the first thin-wall member.

[0011] In one or more embodiments, the flow blocking element extends vertically in a radially inward direction from the radial inner wall of the first thin-wall member.

[0012] In one or more embodiments, the axial position of the flow blocking element corresponds to a front region of the axial position of the labyrinth.

[0013] In one or more embodiments, the sealing member includes a honeycomb bushing.

[0014] In one or more embodiments, the flow blocking element is in the shape of a ring.

[0015] According to a second aspect of the present application, a labyrinth sealing method includes:

[0016] A first thin-wall member is arranged to extend in a rotor part, and a labyrinth is arranged on the radial outer wall of the first thin-wall member;

[0017] A second thin-wall member is arranged to extend in a stator part, and a sealing member corresponding to the labyrinth is arranged on the radial inner wall of the second thin-wall member;

[0018] The extending length of the first thin-wall member is greater than the extending length of the second thin-wall member;

[0019] A flow blocking element is arranged on the radial inner wall of the first thin-wall member, and the blocking direction of the flow blocking element is that the airflow blocked by the flow blocking element after passing through the labyrinth sealing structure from the direction of the airflow flowing from the engine rotor side to the labyrinth sealing structure along the radial inner wall of the first thin-wall member.

[0020] The flow of the airflow along the radial inner wall of the first thin-wall member on the side of the radial inner wall of the first thin-wall member after passing through the labyrinth sealing structure from the direction of the airflow flowing from the engine rotor side to the labyrinth sealing structure.

[0021] In one or more embodiments, the fluid is configured to be blocked by the flow blocking element away from the radial inner wall of the first thin-wall member after passing through the sealing structure of the labyrinth and the sealing member.

[0022] In one or more embodiments, the flow blocking element extends vertically in a radially inward direction from the radial inner wall of the first thin-wall member.

[0023] In one or more embodiments, the axial position of the flow blocking element corresponds to a front region of the axial position of the labyrinth.

[0024] According to a third aspect of the present application, an aero-engine comprises the labyrinth seal structure as described in the first aspect.

[0025] In one or more embodiments, the labyrinth seal structure is located at an engine inter-stage casing and a low pressure turbine rotor junction, the first thin-walled member extends from the low pressure turbine rotor, and the second thin-walled member extends from the inter-stage casing.

[0026] The labyrinth seal structure described above, by the arrangement of the flow blocking element, has a blocking effect on the fluid, the lower side wall surface has no fluid passing through, and the heat transfer coefficient of the rotor side is reduced, so as to slow down the thermal response of the rotor; at the same time, the thickened part increases the volume of the rotor, and increases the heat capacity of the rotor, further slowing down the thermal response of the rotor, so as to improve the transient gap cooperation between the rotor and the stator. The aero-engine adopting the labyrinth seal structure has good safety and reliability. BRIEF DESCRIPTION OF DRAWINGS

[0027] The above and other features, properties, and advantages of the present application will become more apparent by the following description with reference to the accompanying drawings and embodiments, in which:

[0028] Figure 1 is a schematic view of a partial structure of an aero-engine of an embodiment;

[0029] Figure 2 is a schematic view of a labyrinth seal structure of an embodiment;

[0030] Figure 3 is a schematic view of a labyrinth seal structure of a comparative scheme.

[0031] REFERENCE NUMERALS:

[0032] 100 - labyrinth seal structure

[0033] 101 - engine inter-stage casing

[0034] 102 - low pressure turbine rotor

[0035] 1 - rotor part

[0036] 11 - first thin-walled member

[0037] 111 - labyrinth

[0038] 112 - flow blocking element

[0039] 2 - stator part

[0040] 21 - sealing member

[0041] 22 - second thin-walled member. DETAILED DESCRIPTION

[0042] The application will be further described below in connection with specific embodiments and drawings, in which more details are set forth in order to provide a thorough understanding of the application. It will be apparent, however, that the application can be practiced in many different variations without departing from the scope of the application as set forth in the claims. It is understood that the specific examples set forth in the description and in the drawings are intended to be only exemplary and that the scope of the application is not limited to these specific examples.

[0043] It is noted that these and other accompanying drawings are not drawn to scale, and should not be used to construe the actual scope of the application.

[0044] The application uses certain terms to describe the embodiments of the application. As used herein, the terms "one embodiment", "an embodiment", "some embodiments", and / or "one alternative" are intended to mean that a certain feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the application. Therefore, it is understood that the appearances of "one embodiment" or "an embodiment" or "one alternative" or "some embodiments" in various places throughout the specification are not necessarily referring to the same embodiment or alternative. Furthermore, the particular features, structures, or characteristics of one or more embodiments of the application can be combined in any suitable manner.

[0045] The labyrinth seal structure of the comparative solution is shown in Figure 3 The fluid directly flows through the lower wall surface after the labyrinth, and the fluid and the wall surface have a large heat exchange intensity. Since the rotor part on the side of the labyrinth is an elongated thin-walled part, the thermal response is fast, and therefore, during the engine speed-up process, the deformation is not coordinated.

[0046] Specifically, during the engine acceleration process, the labyrinth rotor side rapidly heats up and expands, the rotor side radial deformation changes relatively quickly, the labyrinth gap rapidly decreases, and the collision and grinding easily occur. During the deceleration process, the labyrinth gap rapidly increases and loses the sealing effect.

[0047] Referring to Figure 1 and Figure 2 In some embodiments, the labyrinth seal structure 100 in the aero-engine is located at the connection between the engine inter-stage casing 101 and the low-pressure turbine rotor 102, as shown in Figure 1 The first thin-walled part 11 of the rotor part 1 of the labyrinth seal structure 100 extends from the low-pressure turbine rotor 102, and the second thin-walled part 22 of the stator part 2 extends from the inter-stage casing 101, but this is not limiting, and the labyrinth seal structure 100 introduced in the following embodiments can also be used in other occasions requiring labyrinth sealing in the aero-engine, as well as in any fluid machinery requiring labyrinth sealing.

[0048] Continuing to refer to Figure 1 andFigure 2 As shown, in some embodiments, the comb sealing structure 100 includes a rotor portion 1 and a stator portion 2.

[0049] The rotor portion 1 includes a first thin-walled member 11 extending from the engine rotor, and the radial outer wall of the first thin-walled member 11 is provided with grating teeth 111.

[0050] The stator portion 2 includes a second thin-walled member 22 extending from the engine stator, and the radial inner wall of the second thin-walled member 22 is provided with a sealing member 21 corresponding to the grating teeth 111;

[0051] like Figure 1 As shown, the extension length W1 of the first thin-walled member 11 is greater than the extension length W2 of the second thin-walled member 22.

[0052] like Figure 1 as well as Figure 2 As shown, the radial inner wall of the first thin-walled member 11 is provided with a flow-blocking element 112. The blocking direction of the flow-blocking element 112 is to block the airflow from the engine rotor side to the grate sealing structure 100 and then flow along the radial inner wall of the first thin-walled member 11 after passing through the grate sealing structure 100.

[0053] Preferably, the flow-blocking element 112 extends vertically in a radially inward direction from the radial inner wall of the first thin-walled member 11, providing a good blocking effect and a simple structure. Alternatively, the flow-blocking element 112 can be a ring-shaped structure, which can further improve the blocking effect.

[0054] Preferably, in some embodiments, the axial position of the flow-blocking element 112 corresponds to the area in front of the axial position of the comb teeth 111, for example... Figure 1 as well as Figure 2 As shown, the position is near the first tooth in the axial direction from front to back, which can act as a stop when the fluid initially enters.

[0055] In some embodiments, the sealing element 21 includes a honeycomb bushing, which provides a better sealing effect.

[0056] The above structure, through the setting of flow-blocking elements, has a blocking effect on the fluid, with less fluid passing through the radially inner sidewall, reducing the heat transfer coefficient on the rotor side and thus slowing down the rotor's thermal response; at the same time, the thickened part increases the rotor's volume and increases the rotor's heat capacity, further slowing down the rotor's thermal response, thereby improving the transient clearance fit between the rotor and stator.

[0057] In combination with the above introduction of the labyrinth seal structure, it can be understood that an aero-engine comprising the above labyrinth seal structure can delay the thermal response of the labyrinth stator side under transient and steady state conditions such as accelerated take-off, rapid drop-off, and the like, and optimize the labyrinth gap in the running state, thereby providing a guarantee for the safe operation of the engine.

[0058] It can be understood that the present application also provides a labyrinth seal method, comprising:

[0059] The first thin-walled member 11 is arranged to extend from the rotor portion 1, and the labyrinth 111 is arranged on the radial outer wall of the first thin-walled member 11;

[0060] The second thin-walled member 22 is arranged to extend from the stator portion 2, and the seal member 21 corresponding to the labyrinth 111 is arranged on the radial inner wall of the second thin-walled member 22;

[0061] The extension length of the first thin-walled member 11 is greater than the extension length of the second thin-walled member 22;

[0062] The flow blocking element 112 is arranged on the radial inner wall of the first thin-walled member 11, and the blocking direction of the flow blocking element 112 is:

[0063] The airflow flowing from the engine rotor side to the labyrinth seal structure 100 is blocked by the flow blocking element 112, and then flows along the radial inner wall of the first thin-walled member 11 on the side of the radial inner wall of the first thin-walled member 11.

[0064] In summary, the beneficial effects of the above-mentioned labyrinth seal structure, sealing method, and aero-engine include but are not limited to the following: through the arrangement of the flow blocking element, the fluid is blocked, the lower wall surface is not passed through by the fluid, the heat transfer coefficient of the rotor side is reduced, thereby slowing down the thermal response of the rotor; at the same time, the thickened part increases the volume of the rotor, increases the thermal capacity of the rotor, further slows down the thermal response of the rotor, thereby improving the transient gap cooperation between the rotor and the stator, and the aero-engine adopting the labyrinth seal structure has good safety and reliability.

[0065] Although the present application is disclosed with the above preferred embodiments, it is not intended to limit the present application, and any person skilled in the art can make possible changes and modifications without departing from the spirit and scope of the present application. Therefore, any modification, equivalent change and modification made to the above embodiments according to the technical essence of the present application, which does not deviate from the technical solutions of the present application, falls within the protection scope defined by the claims of the present application.

Claims

1. A labyrinth seal structure (100) characterized by, The application relates to a labyrinth seal structure (100) comprising: a rotor part (1) comprising a first thin-walled part (11) extending from a rotor of an engine, a labyrinth (111) being arranged on a radially outer wall of the first thin-walled part (11); a stator part (2) comprising a second thin-walled part (22) extending from a stator of the engine, a sealing part (21) corresponding to the labyrinth (111) being arranged on a radially inner wall of the second thin-walled part (22); wherein the first thin-walled part (11) has a greater extension than the second thin-walled part (22), and a flow blocking element (112) is arranged on the radially inner wall of the first thin-walled part (11), the flow blocking element (112) being arranged to block a flow of gas, which has passed through the labyrinth seal structure (100) from a direction in which the gas flows from the rotor of the engine towards the labyrinth seal structure (100), from flowing along the radially inner wall of the first thin-walled part (11) on the side of the radially inner wall of the first thin-walled part (11).

2. The labyrinth seal (100) of claim 1, wherein, The flow blocking element (112) extends perpendicularly from the radially inner wall of the first thin-walled part (11) in a direction towards the inside in the radial direction.

3. The labyrinth seal (100) of claim 1, wherein, The flow blocking element (112) is arranged in a region in front of the axial position of the labyrinth (111).

4. The labyrinth seal (100) of claim 1, wherein, The sealing part (21) comprises a honeycomb bushing.

5. The labyrinth seal (100) of claim 1, wherein, The flow blocking element (112) has an annular shape.

6. A labyrinth sealing method, characterized by, The application relates to a labyrinth seal structure (100) comprising: a first thin-walled part (11) extending from a rotor of an engine, a labyrinth (111) being arranged on a radially outer wall of the first thin-walled part (11); a second thin-walled part (22) extending from a stator of the engine, a sealing part (21) corresponding to the labyrinth (111) being arranged on a radially inner wall of the second thin-walled part (22); wherein the first thin-walled part (11) has a greater extension than the second thin-walled part (22); a flow blocking element (112) is arranged on the radially inner wall of the first thin-walled part (11), the flow blocking element (112) being arranged to block a flow of gas, which has passed through the labyrinth seal structure (100) from a direction in which the gas flows from the rotor of the engine towards the labyrinth seal structure (100), from flowing along the radially inner wall of the first thin-walled part (11) on the side of the radially inner wall of the first thin-walled part (11). The fluid is configured to be blocked by the flow blocking element from flowing away from the radially inner wall of the first thin-walled part (11) after passing through the labyrinth (111) and the sealing part (21).

7. The method of claim 6, wherein the screen seal comprises a plurality of screen seal segments. The flow blocking element (112) extends perpendicularly from the radially inner wall of the first thin-walled part (11) in a direction towards the inside in the radial direction.

8. The method of claim 6, wherein the baffle is a screen. The flow blocking element (112) is arranged in a region in front of the axial position of the labyrinth (111).

9. The method of claim 6, wherein the screen seal comprises a plurality of screen seal segments. The application relates to a labyrinth seal structure (100) comprising:

10. An aeroengine characterised in that, The labyrinth seal structure (100) is arranged at a connection between an inter-stage casing of an engine and a low-pressure turbine rotor, the first thin-walled part (11) extending from the low-pressure turbine rotor and the second thin-walled part (22) extending from the inter-stage casing.

11. The aeroengine of claim 10, wherein, ​

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