Sealing structure, sealing method, compressor and gas turbine engine

Abstract

The present application relates to a sealing structure, a sealing method, a compressor and a gas turbine engine. The sealing structure comprises a first part at the root of a stator blade; a second part at the rotor corresponding to the stator blade; wherein the first part and the second part have a sealing gap in the radial direction; wherein the first part comprises a honeycomb body and a protrusion, and the second part comprises a first tooth and a second tooth axially adjacent to each other, the second tooth being downstream of the first tooth; the axial positions of the first tooth and the second tooth correspond to the axial position of the honeycomb body, the axial position of the protrusion corresponds to the first axial area between the first tooth and the second tooth, and the radial position of the protrusion relative to the honeycomb body protrudes radially inward.

Description

Technical Field

[0001] This invention relates to sealing structures, sealing methods, compressors, and gas turbine engines. Background Technology

[0002] The compressor tooth clearance structure of a gas turbine engine, such as an aircraft engine, such as a conventional turbofan engine commonly used in civil aircraft engines, is shown in the attached figure. Figure 1 As shown, after the airflow passes through the rotor blades 100, the pressure increases. After passing through the stator blades 200, the airflow is decelerated and pressurized, and the airflow direction is adjusted. Then, it passes through the next row of rotor blades 100 for further pressurization. This process is repeated to achieve step-by-step pressurization.

[0003] To prevent high-pressure airflow from the stator blade root outlet to the low-pressure area at the blade root inlet from leaking out, a honeycomb 300 is typically designed at the root of the stator blade 200, and a grate 400 is designed at the top of the disk connecting the rotor blade 100 and the next stage rotor blade 100. The gap between the honeycomb 300 and the grate 400 also forms the existing structure of the seal gap, as shown in the attached figure. Figure 1 As shown, the honeycomb remains flat, and the grates adopt a metal structure with three or more sharp teeth. In the working state, the high-pressure airflow at the outlet of the stator blade 100 will flow back along the top of the grates 400 to the low-pressure side of the root inlet of the stator blade 200. During the flow, three low-speed zones 501, 502, and 503 are formed. The airflow velocity in these three low-speed zones is low, indicating that the airflow leakage from the high-pressure side to the low-pressure side is small, which blocks the airflow in the high-pressure zone from continuously flowing to the low-pressure zone.

[0004] Generally speaking, the more and larger the low-speed zone, the better the sealing effect. However, for conventional tooth gap designs... Figure 1 As shown, due to limitations in the axial width and radial height of the honeycomb structure, only two or three rows of grates can be used for sealing. It is impossible to further increase the number of grates or expand the low-speed zone area. Therefore, controlling airflow leakage in the grate gap (sealing gap) area has become a key challenge in the design of high-pressure compressor grate gaps. Summary of the Invention

[0005] One object of the present invention is to provide a sealing structure.

[0006] One object of the present invention is to provide a sealing method.

[0007] One object of the present invention is to provide an air compressor.

[0008] One object of the present invention is to provide a gas turbine engine.

[0009] According to one aspect of the present application, a labyrinth seal structure comprises a first part located at the root of a stator blade; a second part located at a rotor corresponding to the stator blade; wherein the first part and the second part have a sealing gap in the radial direction; wherein the first part comprises a honeycomb body and a protrusion; the second part comprises a first tooth and a second tooth axially adjacent to each other, the second tooth being located downstream of the first tooth; the axial positions of the first tooth and the second tooth correspond to the axial position of the honeycomb body, the axial position of the protrusion corresponds to a first axial area between the first tooth and the second tooth, and the radial position of the protrusion relative to the honeycomb body protrudes radially inward.

[0010] In one or more embodiments of the sealing structure, the honeycomb body is axially interrupted and comprises a first honeycomb body, a second honeycomb body, the first honeycomb body, the protrusion, and the second honeycomb body are sequentially distributed in the axial direction from upstream to downstream; the protrusion is a tooth shape extending radially inward from the root of the stator blade; the structure of the first honeycomb body and the second honeycomb body providing the sealing gap is linear in cross-section, the first axial area is provided with a third honeycomb body, the axial position of the third honeycomb body corresponds to the protrusion, the radial distance between the first tooth and the first honeycomb body, the second tooth and the second honeycomb body, and the protrusion and the third honeycomb body is the sealing gap, and the side edges of the tooth-shaped protrusion have a second axial area and a third axial area in the axial direction with the first honeycomb body and the second honeycomb body axially adjacent to each other.

[0011] In one or more embodiments of the sealing structure, the radial protrusion size of the tooth-shaped protrusion relative to the first honeycomb body and the second honeycomb body is defined as t, the radial size of the first honeycomb body and the second honeycomb body is defined as h1, and 0.1 < t / h1 < 0.3.

[0012] In one or more embodiments of the sealing structure, the third honeycomb body has a groove structure, the radial inner end of the protrusion is located in the depth range of the groove structure, and the low-speed area formed by the sealing structure includes a first low-speed area on the downstream side of the first tooth, a second low-speed area between the first tooth and the protrusion, a third low-speed area between the protrusion and the upstream groove wall of the groove structure, a fourth low-speed area between the protrusion and the downstream groove wall of the groove structure, and a fifth low-speed area between the protrusion and the second tooth.

[0013] In one or more embodiments of the sealing structure, the radial size of the protrusion extending into the depth of the groove structure is defined as n, the depth of the groove structure is defined as m, and 0.4 < n / m < 0.6.

[0014] In one or more embodiments of the seal structure, the honeycomb body is continuous in the axial direction, the protrusions extend radially inward from a radially inner end face of the honeycomb body, the second portion comprises a first tooth, a second tooth and a third tooth distributed from upstream to downstream in the axial direction, the protrusions comprise a first protrusion and a second protrusion, the axial position of the first protrusion corresponds to a first axial region between the first tooth and the second tooth, and the axial position of the second protrusion corresponds to a fourth axial region between the second tooth and the third tooth.

[0015] In one or more embodiments of the seal structure, the radial distance between the first tooth or the second tooth or the third tooth and the honeycomb body is the seal gap, the radial protrusion size of the first protrusion or the second protrusion protruding from the honeycomb body is t, the radial size of the first tooth or the second tooth or the third tooth is h2, and 0.4 < t / h2 < 0.6.

[0016] According to an aspect of the present application, a sealing method is provided, which uses the seal structure as described in the above embodiments. In the air flow direction from low pressure to high pressure, the low speed region formed includes a low speed region located upstream and downstream of the first tooth respectively, a low speed region located upstream and downstream of the protrusion respectively, and a low speed region upstream of the second tooth.

[0017] According to an aspect of the present application, a compressor is provided, which comprises the seal structure as described in the above embodiments.

[0018] According to an aspect of the present application, a gas turbine engine is provided, which comprises the seal structure as described in the above embodiments.

[0019] The further effects of the present application include, but are not limited to, in the case where the number of teeth is limited by the axial width and the radial height of the honeycomb, and the number of teeth can only be three or two in the axial length, and the number of teeth cannot be further increased, i.e. in the case where the axial length is specified, by providing protrusions in the regions corresponding to the honeycomb in the existing scheme, the low speed region is formed between the protrusions and the teeth in the above specified axial length, so as to increase the area of the low speed region, and / or increase the number of low speed regions, so as to enhance the sealing effect, reduce fluid leakage, and thus improve the aerodynamic efficiency of the compressor and the gas turbine engine. BRIEF DESCRIPTION OF DRAWINGS

[0020] The above and other features, properties, and advantages of the present application will become more apparent by reference to the following description of embodiments thereof in conjunction with the accompanying drawings, in which:

[0021] Figure 1Schematic view of a seal structure for a high pressure compressor of an existing gas turbine engine.

[0022] Figure 2 Schematic view of a seal structure of a first embodiment.

[0023] Figure 3 Schematic view of a seal structure of a second embodiment.

[0024] Figure 4 Schematic view of a seal structure of a third embodiment.

[0025] Reference numerals:

[0026] 10 - seal structure

[0027] 1 - first portion

[0028] 11 - honeycomb body

[0029] 111 - first honeycomb body

[0030] 112 - second honeycomb body

[0031] 12 - protrusion

[0032] 121 - first protrusion

[0033] 122 - second protrusion

[0034] 141 - second axial region

[0035] 142 - third axial region

[0036] 151 - first low speed zone

[0037] 152 - second low speed zone

[0038] 153 - third low speed zone

[0039] 154 - fourth low speed zone

[0040] 155 - fifth low speed zone

[0041] 2 - second portion

[0042] 21 - first tooth

[0043] 22 - second tooth

[0044] 23 - first axial region

[0045] 231 - third honeycomb body

[0046] 232 - recess structure

[0047] 2321 - upstream slot wall

[0048] 2322 - downstream slot wall

[0049] 24 - third tooth

[0050] 25 - fourth axial region

[0051] 3 - seal gap

[0052] 100 - rotor blade

[0053] 200 - stator blade

[0054] 300 - honeycomb

[0055] 400 - grid

[0056] 501, 502, 503 - low speed zone DETAILED DESCRIPTION

[0057] Various embodiments of the subject matter described can be disclosed below. For simplicity of disclosure, specific examples of elements and arrangements are described below, but it is to be understood that these are only examples and are not intended to limit the scope of the present application.

[0058] In addition, use of the "a" or "an" to describe aspects of the disclosure are intended to be standalone and are not intended to be limiting. For example, the use of "a" or "an" to describe a feature of the disclosure is intended to be standalone and does not require that more than one of the feature is present. Further, the use of "a" or "an" to describe a feature of the disclosure is intended to be standalone and does not require that more than one of the feature is present. Further, certain features, structures, or characteristics of one or more embodiments of the application can be combined in suitable combinations.

[0059] The following embodiments introduce a seal structure, which can be applied to a gas turbine engine, specifically to a high pressure compressor of a turbofan engine, but not limited to, for example, a marine gas turbine engine, a ground gas turbine, etc., as long as the seal structure is applied to an impeller machine with honeycomb-grid seal structure.

[0060] The existing solution, as shown in Figure 1 The honeycomb remains flat, and the grid uses three or more sharp tooth-like metal structures.

[0061] The inventor found that, due to the axial width and radial height of the honeycomb, only three or two grids can be used for sealing, and it is not possible to further increase the number of grids or expand the low-speed zone area.

[0062] Based on the above, the inventors have invented a new sealing structure that, within the specified axial length, creates a low-speed zone between the protrusion and the teeth to increase the area of ​​the low-speed zone and / or increase the number of low-speed zones, thereby enhancing the sealing effect, reducing fluid leakage, and thus improving the aerodynamic efficiency of compressors and gas turbine engines.

[0063] like Figures 2 to 4 As shown, in some embodiments, the grate sealing structure 10 of the high-pressure compressor of the gas turbine engine includes a first part 1 located at the root of the stator blade 200, corresponding to... Figure 1 The honeycomb 300 region shown in the existing scheme, and the second part 2 of the rotor 30 corresponding to the stator blade, that is, the corresponding Figure 1 The area of ​​the comb teeth 400 in the existing solution is shown. As can be seen above, the axial length of the first part 1 and the second part 2 is limited. Therefore, in the following embodiments, the lengths of the first part 1 and the second part 2 are similar to the axial lengths occupied by the honeycomb 300 and the comb teeth 400 in the existing technical solution, both being a limited length. The first part 1 and the second part 2 have a sealing gap 3 in the radial direction. The first part 1 includes a honeycomb body 11 and a protrusion 12. The second part 2 includes an axially adjacent first tooth 21 and a second tooth 22, with the second tooth 22 located downstream of the first tooth 21. The axial positions of the first tooth 21 and the second tooth 22 correspond to the axial positions of the honeycomb body 11, and the axial positions of the protrusion 12 correspond to the first axial position between the first tooth 21 and the second tooth 22.

[0064] Region 23, the protrusion 12 protrudes radially inward relative to the radial position of the honeycomb body 11.

[0065] The meaning of "stator blade" above is similar to its usual meaning in this field, referring to an important structure that makes up a high-pressure compressor unit, including rotor blades and stator blades. The compressor mainly uses rotor blades to do work on the airflow, thereby generating high-temperature and high-pressure airflow. The stator blades adjust the airflow direction to generate inlet airflow conditions suitable for the rotor blades. The "seal gap," also known as the grate gap, is the area at the root of the stator blade where the honeycomb and grate teeth meet. This area is usually reserved with a gap to prevent scraping, but it also introduces airflow leakage and generates flow losses, therefore, it is necessary to reduce these flow losses.

[0066] The beneficial effects of the above embodiments include, but are not limited to, in the case where the number of teeth is limited by the axial width of the honeycomb, the radial height, and the axial length, i.e. in the case where the number of teeth cannot be further increased in the axial length, and the axial length is specified, by providing the protruding body in the region corresponding to the honeycomb in the existing scheme, a low speed zone is formed between the protruding body and the teeth in the above specified axial length, so as to increase the area of the low speed zone, and / or increase the number of low speed zones, so as to enhance the sealing effect, reduce fluid leakage, and thus improve the aerodynamic efficiency of the compressor and the gas turbine engine. Specifically, the beneficial effects of increasing the area of the low speed zone, and / or increasing the number of low speed zones are further illustrated by the following first to third embodiments.

[0067] As shown in Figure 2 the first embodiment, the honeycomb body 11 is interrupted in the axial direction, including a first honeycomb body 111 and a second honeycomb body 112, the first honeycomb body 111, the protruding body 12, and the second honeycomb body 112 are sequentially distributed in the axial direction from upstream to downstream; the protruding body 12 is a tooth shape extending radially inward from the root of the stator blade; the structure of the first honeycomb body 111 and the second honeycomb body 112 providing the sealing gap 3 is in a straight line shape in the cross section, the first axial region 23 is provided with a third honeycomb body 231, the axial position of the third honeycomb body 231 corresponds to the protruding body 12, the radial distance between the first tooth 21 and the first honeycomb body 11, the second tooth 22 and the second honeycomb body 12, and the protruding body 12 and the third honeycomb body 231 is the sealing gap 3, and the side edges of the tooth-shaped protruding body 12 are respectively provided with a second axial region 141 and a third axial region 142 adjacent to the first honeycomb body 111 and the second honeycomb body 112 in the axial direction.

[0068] As can be seen from the above, the provision of the protruding body 12 increases the area of the low speed zone compared to the existing scheme as shown in Figure 1 , and specifically, the increased area is the space between the side surfaces of the protruding body 12 and the first honeycomb body 111 and the second honeycomb body 112 on the two sides in the axial direction, and the space between the third honeycomb body 231 and the first tooth 21 and the second tooth 22 adjacent thereto, so as to enhance the sealing effect and reduce fluid leakage.

[0069] Continuing to refer to Figure 2 , in some embodiments, the radial protruding dimension of the tooth-shaped protruding body relative to the first honeycomb body 111 and the second honeycomb body 112 is defined as t, the radial dimension of the first honeycomb body 111 and the second honeycomb body 112 is defined as h1, and 0.1 < t / h1 < 0.3. In this way, the sealing effect can be further optimized. Alpha in the figure is the inclination angle of the protruding body 12, which is usually 75° to 85°, and the value in the figure is 80°. A is the length of the side edge of the protruding body 12.

[0070] Reference is made to Figure 3 and in combination with Figure 2 As shown in FIG. 2, in the second embodiment, different from the first embodiment, the third honeycomb body 231 of the second embodiment has a groove structure 232, the radially inner end of the protrusion 12 is located in the depth range of the groove structure 232, the low speed area formed by the sealing structure 10 includes: a first low speed area 151 on the axially downstream side of the first tooth 21, a second low speed area 152 between the first tooth 21 and the protrusion 12, a third low speed area 153 between the protrusion 12 and the upstream groove wall 2321 of the groove structure, a fourth low speed area 154 between the protrusion 12 and the downstream groove wall 2322 of the groove structure, and a fifth low speed area 155 between the protrusion 12 and the second tooth 22. Its beneficial effect is not only to increase the low speed area, but also to increase the low speed area, and further improve the sealing effect.

[0071] Continuing to refer to Figure 3 As shown in FIG. 2, in some embodiments, the radial dimension of the protrusion 12 extending into the depth of the groove structure 232 is defined as n, the depth of the groove structure 232 is defined as m, 0.4 < n / m < 0.6, and the preferred value is 0.5, which can further optimize the sealing effect.

[0072] Reference is made to Figure 4 and in combination with Figure 2 , Figure 3 For the third embodiment, different from the first embodiment and the second embodiment, the third embodiment has an axially continuous honeycomb body 11, and the protrusion 12 of the third embodiment is in the form of a strip, rather than the form of a barb as in the first embodiment and the second embodiment. In the third embodiment, the protrusion 12 extends radially inward from the radially inner end surface of the honeycomb body 11, the second part 2 includes the first tooth 21, the second tooth 22, and the third tooth 24 distributed from the axially upstream to the downstream, and the protrusion 12 includes the first protrusion 121 and the second protrusion 122, the axial position of the first protrusion 121 corresponds to the first axial area 23 between the first tooth 21 and the second tooth 22, and the axial position of the second protrusion 122 corresponds to the fourth axial area 25 between the second tooth 22 and the third tooth 24. In this way, the low speed area can also be increased, and the sealing effect can also be improved.

[0073] Continuing to refer to Figure 4 As shown in FIG. 2, in some embodiments, the radial distance between the first tooth 21 or the second tooth 22 or the third tooth 24 and the honeycomb body 11 is defined as the sealing gap 3, the radial protrusion dimension of the first protrusion 121 or the second protrusion 122 protruding from the honeycomb body 11 is defined as t, the radial dimension of the first tooth 21 or the second tooth 22 or the third tooth 24 is defined as h2, and 0.4 < t / h2 < 0.6, and in some embodiments, the preferred value is 0.5.

[0074] As introduced above, the present application further provides a sealing method for a high-pressure compressor of a gas turbine engine, i.e. in the axial width of the existing technology as shown in Figure 1 As introduced above, the present application further provides a sealing method for a high-pressure compressor of a gas turbine engine, i.e. in the axial width of the existing technology as shown in Figure 3 、 Figure 4 As introduced above, the present application further provides a sealing method for a high-pressure compressor of a gas turbine engine, i.e. in the axial width of the existing technology as shown in

[0075] As introduced above, the present application further provides a sealing method for a high-pressure compressor of a gas turbine engine, i.e. in the axial width of the existing technology as shown in

[0076] Although the above embodiments are disclosed as above, the present application is not intended to be limited thereto, 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 in accordance with the technical essence of the present application, without departing from the technical solutions of the present application, shall fall within the protection scope defined by the claims of the present application.

Claims

1. A serration seal structure (10) characterized by, Comprise: a first part (1) located at the root of a stator blade (200); a second part (2) located at a rotor (30) corresponding to the stator blade; wherein the first part (1) and the second part (2) have a sealing gap (3) in the radial direction; wherein the first part (1) comprises a honeycomb body (11) and a protruding body (12); the second part (2) comprises a first tooth (21) and a second tooth (22) axially adjacent to each other, the second tooth (22) being located downstream of the first tooth (21); the axial positions of the first tooth (21) and the second tooth (22) correspond to the axial position of the honeycomb body (11), the axial position of the protruding body (12) corresponds to a first axial area (23) between the first tooth (21) and the second tooth (22), and the radial position of the protruding body (12) relative to the honeycomb body (11) protrudes radially inward; the honeycomb body (11) is axially interrupted and comprises a first honeycomb body (111) and a second honeycomb body (112), the first honeycomb body (111), the protruding body (12), and the second honeycomb body (112) are sequentially distributed in the axial direction from upstream to downstream; the protruding body (12) is a tooth shape extending radially inward from the root of the stator blade; the structures of the first honeycomb body (111) and the second honeycomb body (112) providing the sealing gap (3) are linear in cross-section, the first axial area (23) is provided with a third honeycomb body (231), the axial position of the third honeycomb body (231) corresponds to the protruding body (12), the radial distances between the first tooth (21) and the first honeycomb body (111), the second tooth (22) and the second honeycomb body (112), and the protruding body (12) and the third honeycomb body (231) are all the sealing gap (3), the sides of the tooth-shaped protruding body (12) have a second axial area (141) and a third axial area (142) in the axial direction with the axially adjacent first honeycomb body (111) and second honeycomb body (112), respectively; the third honeycomb body (231) has a groove structure (232), the radial inner end of the protruding body (12) is located in the depth range of the groove structure (232), and the low-speed area formed by the sealing structure (10) comprises a first low-speed area (151) on the downstream side of the first tooth (21) in the axial direction, a second low-speed area (152) between the first tooth (21) and the protruding body (12), a third low-speed area (153) between the protruding body (12) and the upstream groove wall (2321) of the groove structure, a fourth low-speed area (154) between the protruding body (12) and the downstream groove wall (2322) of the groove structure, and a fifth low-speed area (155) between the protruding body (12) and the second tooth (22).

2. The seal structure (10) as claimed in claim 1, characterized in that The radial protruding size of the tooth-shaped protrusion relative to the first honeycomb body (111) and the second honeycomb body (112) is defined as t, the radial size of the first honeycomb body (111) and the second honeycomb body (112) is defined as h1, and 0.1 < t / h1 < 0.

3.

3. The seal structure (10) of claim 1, wherein, The radial size of the protrusion (12) extending into the groove structure (232) is defined as n, the depth of the groove structure (232) is defined as m, and 0.4 < n / m < 0.

6.

4. The seal structure (10) of claim 1, wherein, The honeycomb body (11) is continuous in the axial direction, the protrusion (12) extends radially inward from the radially inner end surface of the honeycomb body (11), the second part (2) includes a first tooth (21), a second tooth (22), and a third tooth (24) distributed from upstream to downstream in the axial direction, the protrusion (12) includes a first protrusion (121) and a second protrusion (122), the axial position of the first protrusion (121) corresponds to a first axial region (23) between the first tooth (21) and the second tooth (22), and the axial position of the second protrusion (122) corresponds to a fourth axial region (25) between the second tooth (22) and the third tooth (24).

5. The seal structure (10) as claimed in claim 4, characterized in that The radial distance between the first tooth (21), the second tooth (22), or the third tooth (24) and the honeycomb body (11) is the sealing gap (3), the radial protruding size of the first protrusion (121) or the second protrusion (122) protruding from the honeycomb body (11) is defined as t, the radial size of the first tooth (21), the second tooth (22), or the third tooth (24) is defined as h2, and 0.4 < t / h2 < 0.

6.

6. A method of sealing, characterized by The sealing structure (10) according to any one of claims 1-5, in the air flow direction from low pressure to high pressure, the low speed area formed includes a low speed area located upstream and downstream of the first tooth (21) respectively, a low speed area located upstream and downstream of the protrusion (12) respectively, and a low speed area upstream of the second tooth (22).

7. A compressor characterized by, The sealing structure (10) according to any one of claims 1-5.

8. A gas turbine engine characterized by, The sealing structure (10) according to any one of claims 1-5.

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