Sealing structure, sealing method, gas compressor and gas turbine engine

Abstract

The invention relates to a sealing structure, a sealing method, a gas compressor and a gas turbine engine. The sealing structure comprises a first part and a second part, wherein the first part is located at the root of the stator blade; the second part is positioned on the rotor corresponding to the stator blade; a sealing gap is formed between the first part and the second part in the radial direction; wherein the first part comprises a honeycomb body and a protruding body, the second part comprises a first tooth and a second tooth which are adjacent in the axial direction, and the second tooth is located on the downstream of the first tooth; the axial positions of the first teeth and the second teeth correspond to the axial position of the honeycomb body, the axial position of the protruding body corresponds to a first axial area between the first teeth and the second teeth, and the protruding body protrudes inwards in the radial direction relative to the radial position of the honeycomb body.

Description

Technical Field

[0001] The invention relates to a sealing structure, a sealing method, a compressor and a gas turbine engine. Background Art

[0002] The grate clearance structure of the compressor of a gas turbine engine, such as an aircraft engine, such as a turbofan engine commonly used in a civil aircraft engine is shown in the attached figure. Figure 1 As shown, after the airflow passes through the rotor blades 100, the pressure increases, and the airflow passes through the stator blades 200 to complete the deceleration and pressure increase, adjust the airflow direction, and then pass through the next row of rotor blades 100 for pressure increase, alternating back and forth to achieve step-by-step pressure increase.

[0003] In order to prevent the high-pressure airflow at the root outlet of the stator blade 200 from leaking to the low-pressure area at the root inlet, a honeycomb 300 is usually designed at the root of the stator blade 200, and a grate 400 is designed at the top of the wheel connecting the rotor blade 100 and the rotor blade 100 of the next stage. The grate gap between the honeycomb 300 and the grate 400 is also called a seal gap. Figure 1 As shown, the honeycomb remains flat, and the comb teeth adopt three or more sharp-toothed metal structures. In the working state, the high-pressure airflow at the outlet of the stator blade 100 will flow back along the top of the comb teeth 400 to the low-pressure side of the root inlet of the stator blade 200, and three low-speed areas 501, 502, and 503 are formed during the flow. The air flow velocities in these three low-speed areas are relatively low, indicating that the airflow leakage from the high-pressure side to the low-pressure side is relatively small, which blocks the airflow in the high-pressure area from continuing to flow to the low-pressure area.

[0004] Generally speaking, the more low-speed areas there are, the larger the area, and the better the sealing effect. Figure 1 As shown in the figure, due to the limitation of honeycomb axial width and radial height, only three or two grate teeth can be used for sealing, and the number of grate teeth cannot be further increased, nor can the low-speed area be expanded. Therefore, how to control the airflow leakage in the grate tooth gap (sealing gap) area has become a difficulty in the current design of high-pressure compressor grate tooth gap. Summary of the invention

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

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

[0007] An object of the present invention is to provide a compressor.

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

[0009] According to one aspect of the present invention, a comb tooth sealing structure comprises a first part located at the root of a stator blade; and a second part located at a rotor corresponding to the stator blade; wherein a sealing gap exists between the first part and the second part 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 adjacent to each other in the axial direction, and the second tooth is 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 the first axial region between the first tooth and the second tooth, and the protrusion protrudes radially inward relative to the radial position of the honeycomb body.

[0010] In one or more embodiments of the sealing structure, the honeycomb body is interrupted in the axial direction, and includes a first honeycomb body and a second honeycomb body, and 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 tooth-shaped extending radially inward from the root of the stator blade; the structure in which the first honeycomb body and the second honeycomb body provide a sealing gap is linear in cross section, a third honeycomb body is provided in the first axial region, and the axial position of the third honeycomb body corresponds to the protrusion, and the radial spacing 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 are all the sealing gaps, and the side edges of the tooth-shaped protrusion respectively have a second axial region and a third axial region in the axial direction with the axially adjacent first honeycomb body and second honeycomb body.

[0011] In one or more embodiments of the sealing structure, the radial protrusion size of the toothed protrusion relative to the first honeycomb body and the second honeycomb body is defined as t, and the radial size of the first honeycomb body and the second honeycomb body is defined as h1, 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 within the depth range of the groove structure, and the low-speed zone formed by the sealing structure includes: a first low-speed zone on the axial downstream side of the first tooth, a second low-speed zone between the first tooth and the protrusion, a third low-speed zone between the protrusion and the upstream groove wall of the groove structure, a fourth low-speed zone between the protrusion and the downstream groove wall of the groove structure, and a fifth low-speed zone between the protrusion and the second tooth.

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

[0014] In one or more embodiments of the sealing structure, the honeycomb body is continuous in the axial direction, the protrusion extends radially inward from the radial inner end surface of the honeycomb body, the second part includes a first tooth, a second tooth and a third tooth distributed from axial upstream to downstream, and the protrusion includes 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 sealing structure, the radial distance between the first tooth, the second tooth or the third tooth and the honeycomb body is the sealing gap, the radial protrusion dimension of the first protrusion or the second protrusion protruding from the honeycomb body is defined as t, and the radial dimension of the first tooth, the second tooth or the third tooth is defined as h2, 0.4 <t / h2<0.6。

[0016] According to a sealing method of one aspect of the present invention, the sealing structure as described in the above embodiment is adopted. In the airflow direction from low pressure to high pressure, the low-speed zone formed includes low-speed zones located respectively upstream and downstream of the first tooth, low-speed zones located respectively upstream and downstream of the protrusion, and a low-speed zone upstream of the second tooth.

[0017] A compressor according to one aspect of the present invention includes the sealing structure as described in the above embodiments.

[0018] A gas turbine engine according to one aspect of the present invention comprises the sealing structure as described in the above embodiments.

[0019] The improved effects of the present invention include, but are not limited to, when the axial width and radial height of the honeycomb are limited and only three or two comb teeth can be used for sealing in the axial length, and the number of comb teeth cannot be further increased, that is, under the specified axial length, by arranging a protrusion in the area corresponding to the honeycomb in the existing scheme, a low-speed zone is formed between the protrusion and the comb teeth under 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 gas turbine engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] 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. It should be noted that the drawings are only examples and are not drawn to scale, and should not be used as a limitation on the actual scope of protection required by the present invention, wherein:

[0021] Figure 1The diagram is a schematic diagram of the sealing structure of the high-pressure compressor of an existing gas turbine engine.

[0022] Figure 2 FIG. 1 is a schematic diagram of the sealing structure of the first embodiment.

[0023] Figure 3 FIG. 4 is a schematic diagram of a sealing structure of the second embodiment.

[0024] Figure 4 FIG. 4 is a schematic diagram of a sealing structure of a third embodiment.

[0025] Some reference numerals:

[0026] 10-Sealing structure

[0027] 1-Part 1

[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 area

[0036] 151-1st low speed zone

[0037] 152-Second low speed zone

[0038] 153-Third slow speed zone

[0039] 154-Fourth Low Speed ​​Zone

[0040] 155-Fifth Low Speed ​​Zone

[0041] 2-Part 2

[0042] 21-First tooth

[0043] 22- Second tooth

[0044] 23-First axial region

[0045] 231-third honeycomb body

[0046] 232-groove structure

[0047] 2321-Upstream tank wall

[0048] 2322-Downstream slot wall

[0049] 24-Third tooth

[0050] 25-Fourth axial region

[0051] 3-Seal gap

[0052] 100-Rotor blades

[0053] 200-Stator blade

[0054] 300-Cellular

[0055] 400-comb teeth

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

[0057] The following discloses various different implementation methods or embodiments of the subject technical solution. To simplify the disclosure, specific examples of various elements and arrangements are described below. Of course, these are only examples and are not intended to limit the scope of protection of the present invention.

[0058] In addition, the use of "one embodiment", "an embodiment", and / or "some embodiments" means a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "one embodiment" or "one or more embodiments" mentioned twice or more in different places in this specification do not necessarily refer to the same embodiment. In addition, certain features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.

[0059] The sealing structure introduced in the following embodiments is applied to a gas turbine engine, specifically, a high-pressure compressor of a turbofan engine as an example, but is not limited to this. For example, it can also be a marine gas turbine engine, a ground gas turbine, etc. As long as the impeller machinery adopts a honeycomb-comb tooth sealing structure, the sealing structure of this case can be applied.

[0060] Existing solutions include Figure 1 As shown, the honeycomb remains flat, and the comb teeth adopt a metal structure with three or more sharp teeth.

[0061] The inventors found that, due to the limitation of the honeycomb axial width and radial height, only three or two rows of comb teeth can be used for sealing, and it is impossible to further increase the number of comb teeth and expand the area of ​​the low-speed zone.

[0062] Based on the above, the inventors have invented a new sealing structure, which, under the axial length specified above, forms a low-speed zone between the protrusion and the comb teeth to increase the area of ​​the low-speed zone, and / or increase the number of low-speed zones to enhance the sealing effect and reduce fluid leakage, thereby improving the aerodynamic efficiency of the compressor and gas turbine engine.

[0063] like Figures 2 to 4 As shown, in some embodiments, the grate seal structure 10 of the high pressure compressor of the gas turbine engine includes a first portion 1 located at the root of the stator blade 200, that is, corresponding to Figure 1 The region of the honeycomb 300 in the prior art shown, and the second portion 2 of the rotor 30 corresponding to the stator blade, i.e., corresponding to Figure 1 The area of ​​the comb teeth 400 in the prior art solution shown. As can be seen from the above, the axial lengths of the first part 1 and the second part 2 are limited. Therefore, the lengths of the first part 1 and the second part 2 in the following embodiments are similar to the axial lengths of the honeycomb 300 and the comb teeth 400 in the prior art solution, and are all limited lengths. Among them, there is a sealing gap 3 in the radial direction between the first part 1 and the second part 2; wherein the first part 1 includes a honeycomb body 11 and a protrusion 12; the second part 2 includes a first tooth 21 and a second tooth 22 adjacent in the axial direction, and the second tooth 22 is 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, and the axial position of the protrusion 12 corresponds to the first axial position between the first tooth 21 and the second tooth 22.

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

[0065] The meaning of "stator blades" above is similar to the general meaning in this field, that is, the important structure that constitutes the high-pressure compressor unit, including rotor blades and stator blades. The compressor mainly works on the airflow through the rotor blades, thereby generating high-temperature and high-pressure airflow, and adjusts the airflow direction through the stator blades to produce inlet airflow conditions suitable for the rotor blades. "Seal gap" is also called the comb gap, which is the area where the honeycomb at the root of the stator blade is combined with the comb teeth. This area usually reserves a part of the gap to prevent scraping, but at the same time it causes airflow leakage and generates flow losses, so the flow losses need to be reduced.

[0066] The beneficial effects of adopting the above embodiments include, but are not limited to, being restricted by the axial width and radial height of the honeycomb, and only three or two labyrinth seals can be used in the axial length for sealing, and it is impossible to further increase the number of labyrinth seals. That is, within the specified axial length, by setting protrusions in the area corresponding to the honeycomb in the existing solution, a low-speed area is formed between the protrusions and the labyrinth seals within the above-specified axial length, so as to increase the area of the low-speed area and / or increase the number of low-speed areas, enhance the sealing effect, reduce fluid leakage, and thus improve the aerodynamic efficiency of the compressor and gas turbine engine. Specifically, the beneficial effects of increasing the area of the low-speed area and / or increasing the number of low-speed areas are further described through the following first to third embodiments.

[0067] As Figure 2 shown, in the first embodiment, the honeycomb body 11 is axially interrupted, including a first honeycomb body 111 and a second honeycomb body 112. The first honeycomb body 111, the protrusion 12, and the second honeycomb body 112 are sequentially distributed axially from upstream to downstream; the protrusion 12 is tooth-shaped and extends radially inward from the root of the stator vane; the structures of the first honeycomb body 111 and the second honeycomb body 112 providing the sealing gap 3 are linear in cross-section. A third honeycomb body 231 is provided in the first axial region 23, and the axial position of the third honeycomb body 231 corresponds to the protrusion 12. The radial distances between the first tooth 21 and the first honeycomb body 11, the second tooth 22 and the second honeycomb body 12, and the protrusion 12 and the third honeycomb body 231 are all the sealing gap 3. The sides of the tooth-shaped protrusion 12 and the adjacent first honeycomb body 111 and second honeycomb body 112 in the axial direction have a second axial region 141 and a third axial region 142 respectively.

[0068] As can be seen from the above, the setting of the protrusion 12, compared with Figure 1 the existing solution shown, increases the area of the low-speed area. Specifically, the increased area is the space between the sides of the protrusion 12 and the first honeycomb body 111 and the second honeycomb body 112 on both axial sides, and the space between the third honeycomb body 231 and the adjacent first tooth 21 and second tooth 22, thereby enhancing the sealing effect and reducing fluid leakage.

[0069] Continuing to refer to Figure 2 shown, in some embodiments, the radial protrusion dimension of the tooth-shaped protrusion relative to the first honeycomb body 111 and the second honeycomb body 112 is defined as t, and 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. This can further optimize the sealing effect. Alpha shown in the figure is the inclination angle of the protrusion 12, usually 75° - 85°, and the value in the figure is 80°. a is the length of the side of the protrusion 12.

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

[0071] Continue to refer to Figure 3 As shown, in some embodiments, the radial dimension of the protruding body 12 extending into the depth of the groove structure 232 is defined as n, and the depth of the groove structure 232 is defined as m, where 0.4 < n / m < 0.6, and a further preferred value is 0.5. In this way, the sealing effect can be further optimized.

[0072] Refer to Figure 4 As shown, and in combination with Figure 2 , Figure 3 , for the third embodiment, different from the first and second embodiments, the honeycomb body 11 of the third embodiment is axially continuous rather than interrupted. The protruding body 12 of the third embodiment is strip-shaped, rather than the protruding body 12 in the first and second embodiments being comb-shaped similar to the first tooth 21 and the second tooth 22. In the third embodiment, the protruding body 12 extends radially inward from the radially inner end face 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. The protruding body 12 includes the first protruding body 121 and the second protruding body 122. The axial position of the first protruding body 121 corresponds to the first axial region 23 between the first tooth 21 and the second tooth 22, and the axial position of the second protruding body 122 corresponds to the fourth axial region 25 between the second tooth 22 and the third tooth 24. In this way, it is also possible to increase the low-speed area and improve the sealing effect.

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

[0074] As described above, the present application also provides a sealing method for a high pressure compressor of a gas turbine engine, that is, Figure 1 In the specified axial width of the prior art shown in the figure, the sealing structure 10 as described in the above embodiment is used, and in the airflow direction from low pressure to high pressure, the low speed area formed includes the low speed area located upstream and downstream of the first tooth 21, the low speed area located upstream and downstream of the protrusion 12, and the low speed area upstream of the second tooth 22. Specifically, for example Figure 3 , Figure 4 As shown, within the specified axial length of the three comb teeth, a first low-speed zone, a second low-speed zone, a third low-speed zone, a fourth low-speed zone and a fifth low-speed zone can be formed to improve the sealing effect.

[0075] As can be seen from the above, the improved effects of the sealing structure, sealing method, compressor and gas turbine engine introduced in the above embodiments include but are not limited to, when the axial width and radial height of the honeycomb are limited and only three or two comb teeth can be used for sealing in the axial length, and the number of comb teeth cannot be further increased, that is, under the specified axial length, by arranging a protrusion in the area corresponding to the honeycomb in the existing scheme, a low-speed zone is formed between the protrusion and the comb teeth under 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 gas turbine engine.

[0076] Although the present invention is disclosed as above with the above embodiments, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, any modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope defined by the claims of the present invention.

Claims

1. A comb teeth sealing structure (10), characterized in that: include: A first portion (1) located at the root of the stator blade (200); A second portion (2) of the rotor (30) located corresponding to the stator blade; Wherein, a sealing gap (3) exists between the first part (1) and the second part (2) in the radial direction; Wherein, the first part (1) comprises a honeycomb body (11) and a protrusion (12); The second portion (2) comprises a first tooth (21) and a second tooth (22) adjacent to each other in the axial direction, wherein the second tooth (22) is 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), the axial position of the protrusion (12) corresponds to the first axial region (23) between the first tooth (21) and the second tooth (22), and the protrusion (12) protrudes radially inward relative to the radial position of the honeycomb body (11).

2. The sealing structure (10) according to claim 1, characterized in that: The honeycomb body (11) is interrupted in the axial direction and comprises a first honeycomb body (111) and a second honeycomb body (112); the first honeycomb body (111), the protrusion (12), and the second honeycomb body (112) are sequentially distributed in the axial direction from upstream to downstream; the protrusion (12) is tooth-shaped and extends radially inward from the root of the stator blade; the structure of the sealing gap (3) provided by the first honeycomb body (111) and the second honeycomb body (112) is linear in 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 protrusion (12), the radial spacing between the first tooth (21) and the first honeycomb body (11), the radial spacing between the second tooth (22) and the second honeycomb body (12), and the protrusion (12) and the third honeycomb body (231) are all the sealing gap (3), and the side edges of the tooth-shaped protrusion (12) respectively have a second axial region (141) and a third axial region (142) axially with the axially adjacent first honeycomb body (111) and second honeycomb body (112).

3. The sealing structure (10) according to claim 2, characterized in that: The radial protrusion size of the tooth-shaped protrusion relative to the first honeycomb body (111) and the second honeycomb body (112) is defined as t, and the radial size of the first honeycomb body (111) and the second honeycomb body (112) is defined as h1, 0.1 <t / h1<0.3。 4. The sealing structure (10) according to claim 2, characterized in that: The third honeycomb body (231) has a groove structure (232), the radial inner end of the protrusion (12) is located within the depth range of the groove structure (232), and the low-speed zone formed by the sealing structure (10) includes: a first low-speed zone (151) on the axial downstream side of the first tooth (21), a second low-speed zone (152) between the first tooth (21) and the protrusion (12), a third low-speed zone (153) between the protrusion (12) and the upstream groove wall (2321) of the groove structure, a fourth low-speed zone (154) between the protrusion (12) and the downstream groove wall (2322) of the groove structure, and a fifth low-speed zone (155) between the protrusion (12) and the second tooth (22).

5. The sealing structure (10) according to claim 4, characterized in that: The radial dimension of the depth 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。 6. The sealing structure (10) according to claim 1, characterized in that: The honeycomb body (11) is continuous in the axial direction; the protrusion (12) extends radially inward from the radial inner end surface of the honeycomb body (11); the second portion (2) comprises a first tooth (21), a second tooth (22) and a third tooth (24) distributed from the upstream to the downstream in the axial direction; the protrusion (12) comprises 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); 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).

7. The sealing structure (10) according to claim 6, characterized in that: The radial distance between the first tooth (21) or the second tooth (22) or the third tooth (24) and the honeycomb body (11) is 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, 0.4 <t / h2<0.6。 8. A sealing method, characterized in that: By adopting the sealing structure (10) as described in any one of claims 1 to 7, in the airflow direction from low pressure to high pressure, the low-speed zone formed includes low-speed zones located upstream and downstream of the first tooth (21), low-speed zones located upstream and downstream of the protrusion (12), and a low-speed zone upstream of the second tooth (22).

9. A compressor, characterized in that: It comprises a sealing structure (10) as claimed in any one of claims 1 to 7.

10. A gas turbine engine, characterized in that: It comprises a sealing structure (10) as claimed in any one of claims 1 to 7.

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