Sealing and cooling device for turbine disc cavity of gas turbine

Abstract

The invention relates to the technical field of gas turbines, in particular to a gas turbine turbine disc cavity sealing and cooling device which comprises a first flow guide assembly arranged between a turbine first-stage movable impeller disc and a second-stage partition plate and a second flow guide assembly arranged between a turbine second-stage movable impeller disc and the second-stage partition plate. The second-stage partition plate is of a symmetrical hollow structure; and the sealing assembly is arranged on the inner side of the second-stage partition plate. The cooling device has the beneficial effects that the arranged flow guide assemblies can generate a suction effect on cooling air entering the inner cavities of the movable blades under the action of the rotating centrifugal force of the wheel disc, contraction flow channels are formed between the flow guide pieces, the flow speed of the cooling air is increased, the heat exchange effect of the cooling air and the movable blades is enhanced, and the cooling efficiency is improved; the flow deflectors are connected with the wheel disc through bolts, the minimum sectional area of a contraction flow channel formed by the flow deflectors is changed by adjusting the angles of the flow deflectors, and the flow of cooling air entering the inner cavities of the movable blades can be adjusted.

Description

Technical Field

[0001] The invention relates to the technical field of gas turbines, in particular to a gas turbine turbine disc cavity sealing cooling device. Background Art

[0002] As one of the core components of a gas turbine, the turbine plays a vital role in the entire gas turbine system. The disc cavity sealing structure is an important and complex part of the gas turbine system, and its stability and reliability are directly related to the performance and efficiency of the gas turbine.

[0003] In the prior art, only the turbine seal or the turbine disc cavity structure is often considered separately, without comprehensively considering the cooling effect of the turbine disc cavity structure and the sealing effect of the seal structure. Summary of the invention

[0004] In view of the above problems or problems existing in the prior art, the present invention is proposed.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: A gas turbine turbine disc cavity sealing cooling device, comprising a first guide assembly arranged between a first-stage impeller disc of a turbine and a second-stage partition plate, and a second guide assembly arranged between a second-stage impeller disc of a turbine and a second-stage partition plate, wherein the second-stage partition plate is a symmetrical hollow structure;

[0006] Also included is a sealing assembly disposed inside the second-stage partition.

[0007] As a preferred solution of the gas turbine turbine disc cavity sealing cooling device of the present invention, the first guide assembly includes a first guide vane group arranged in a circumferential ring along the first stage impeller disc of the turbine, the first guide vane group is contracted along the radial direction, and the first guide vane group is composed of a plurality of first guide vanes of the same shape and structure;

[0008] The air inlet of each turbine first-stage moving blade corresponds to two first guide vanes.

[0009] As a preferred solution of the gas turbine turbine disc cavity sealing cooling device of the present invention, the first guide vane includes a first air inlet end and a first air outlet end, and the thickness of the first air inlet end is greater than the thickness of the first air outlet end, wherein the first air inlet end is the end away from the air inlet of the first stage moving blade of the turbine.

[0010] As a preferred solution of the gas turbine turbine disc cavity sealing cooling device of the present invention, the second guide assembly includes a second guide vane group arranged in a circumferential ring along the second-stage impeller disc, the second guide vane group is contracted in the radial direction, and the second guide vane group is composed of a plurality of second guide vanes with the same shape and structure;

[0011] The air inlet of each turbine second-stage moving blade corresponds to two second guide vanes.

[0012] As a preferred solution of the gas turbine turbine disc cavity sealing cooling device of the present invention, the second guide vane includes a second air inlet end and a second air outlet end, and the thickness of the second air inlet end is greater than the thickness of the second air outlet end, wherein the second air inlet end is an end away from the air inlet of the second stage moving blade of the turbine.

[0013] As a preferred solution of the gas turbine turbine disc cavity sealing cooling device of the present invention, the second-stage partition includes a base, a group of protruding wings symmetrically arranged on the base, and a first comb tooth arranged on the outer surface of the upper end of the protruding wing.

[0014] As a preferred solution of the gas turbine turbine disc cavity sealing cooling device of the present invention, a group of mounting grooves are formed at the connection between a group of protruding wings and the base, and the two mounting grooves are respectively adapted to the bosses of the corresponding turbine first-stage impeller disc or the turbine second-stage impeller disc.

[0015] As a preferred solution of the gas turbine turbine disc cavity sealing cooling device of the present invention, wherein: the sealing assembly comprises a second-stage sealing ring and a second-stage sealing ring cooling air hole;

[0016] The second-stage sealing ring comprises a second groove arranged opposite to the top end of the extended wing, and a second comb tooth arranged at the second groove, wherein the first comb tooth and the second comb tooth are arranged opposite to each other.

[0017] As a preferred solution of the gas turbine turbine disc cavity sealing cooling device of the present invention, the top end of the second-stage sealing ring is connected to the second-stage stationary blade of the turbine through a hanging ear and a slot.

[0018] As a preferred solution of the gas turbine turbine disc cavity sealing cooling device of the present invention, the inner cavity cross-section of the second-stage sealing ring is in an "inverted soil" shape.

[0019] Beneficial effects of the present invention: The present invention provides a guide assembly, which can produce a suction effect on the cooling air entering the inner cavity of the moving blade under the action of the centrifugal force of the rotating wheel, and form a contraction flow channel between the guide vanes, thereby increasing the cooling air flow rate, strengthening the heat exchange effect between the cooling air and the moving blades, and improving the cooling efficiency. Furthermore, the guide vane and the wheel are connected by bolts, and the minimum cross-sectional area of ​​the contraction flow channel formed by the guide vane is changed by adjusting the angle of the guide vane, so that the cooling air flow entering the inner cavity of each moving blade can be adjusted. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0021] Figure 1 It is a cross-sectional schematic diagram of a gas turbine turbine disc cavity seal cooling device.

[0022] Figure 2 Schematic diagram of cooling air flow in gas turbine turbine disc cavity seal cooling device.

[0023] Figure 3 The figure is a schematic diagram of the sealing assembly of the gas turbine turbine disc cavity sealing cooling device.

[0024] Figure 4 Schematic diagram of the three-dimensional structure of the roulette wheel.

[0025] Figure 5 Schematic diagram of cooling air flow for part of the wheel.

[0026] Figure 6 Schematic diagram of the guide vane in two dimensions and three dimensions.

[0027] Figure 7 Schematic diagram of the connection between the guide vane and the wheel.

[0028] Figure 8 Schematic diagram of the countersunk hole structure opened on the wheel guide plate.

[0029] Fig. 9 It is a schematic diagram of the structure of the second-stage partition and the second-stage sealing ring.

[0030] Fig.10 Schematic diagram of the connection between the wheel and the second-stage partition. DETAILED DESCRIPTION

[0031] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0032] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0033] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0034] Example

[0035] Reference Figures 1 to 10 , is an embodiment of the present invention, which provides a gas turbine turbine disc cavity sealing cooling device, comprising a first guide assembly 200 arranged between a first-stage turbine impeller disc 101 and a second-stage partition plate 102, and a second guide assembly 300 arranged between a second-stage turbine impeller disc 103 and a second-stage partition plate 102, wherein the second-stage partition plate 102 is a symmetrical hollow structure;

[0036] Also included is a sealing assembly 400 disposed inside the second-stage diaphragm 102 .

[0037] It should be noted that the turbine first-stage impeller disk 101 and the turbine second-stage impeller disk 103 form a cooling air contraction flow channel under the arrangement of the first guide assembly 200, the second guide assembly 300 and the second-stage partition 102, which can accelerate the flow rate of the cooling air when entering the inner cavity of each impeller, thereby enhancing the convection and impact cooling effect inside the impeller.

[0038] Preferably, in order to reduce the weight of the wheel, the second-stage partition 102 is designed to be a hollow structure to ensure that the outer rotor cooling air and the inner stationary blade inner cavity outlet cooling air fully cool it to prevent excessive temperature from causing ablation and high-temperature thermal stress.

[0039] Furthermore, the first guide assembly 200 includes a first guide vane group 201 arranged circumferentially around the first-stage impeller disk 101 of the turbine, and the first guide vane group 201 is contracted in the radial direction, wherein the first guide vane group 201 is composed of a plurality of first guide vanes 201a of the same shape and structure, and the first guide vanes 201a act as fins, so that the heat exchange effect between the rotor cooling air and the disk is enhanced;

[0040] The air inlet of each turbine first-stage moving blade 101a corresponds to two first guide vanes 201a.

[0041] It should be noted that each first guide vane 201a has two adjacent first guide vanes 201a. The two first guide vanes 201a acting on the air inlet of the same turbine first-stage moving blade 101a with one adjacent first guide vane 201a are called a grouped guide vane, and together with another adjacent first guide vane 201a are called an adjacent guide vane group.

[0042] Furthermore, the first guide vane 201a includes a first air inlet end 201a-1 and a first air outlet end 201a-2, and the thickness of the first air inlet end 201a-1 is greater than the thickness of the first air outlet end 201a-2, wherein the first air inlet end 201a-1 is an end away from the air inlet of the first-stage turbine blade 101a, and the air inlet ends of adjacent guide vane groups are in contact, so that cooling air can only enter the internal cavity of each blade through the contraction channel formed by the first guide vane, thereby cooling the blade.

[0043] It should be noted that each first air inlet end 201a-1 and the first-stage impeller disk 101 of the turbine are provided with corresponding countersunk holes, and the two are connected by bolts. The thickness of the first air inlet end 201a-1 is greater than the thickness of the first air outlet end 201a-2, so that the bolts will not be exposed, and further the outer side of the second-stage partition 102 can match the shape of the first guide vane 201a.

[0044] Preferably, the thickness of the first air inlet end 201a-1 is greater than the thickness of the first air outlet end 201a-2. The countersunk hole is provided at the first air inlet end 201a-1 to ensure the connection strength of the bolts. At the same time, the position of the bolt connection is provided at the first air inlet end 201a-1, so that when the angle of the first guide vane 201a is adjusted, the first air inlet end 201a-1 only needs to rotate a very small angle to achieve a larger change in the area of ​​the contraction flow channel at the air outlet end of the grouped guide vanes. Furthermore, adjusting the angle can change the minimum cross-sectional area of ​​the contraction flow channel, thereby adjusting the cooling air flow of each blade.

[0045] Furthermore, the second guide assembly 300 includes a second guide vane group 301 arranged in a circumferential array along the second-stage impeller disk, and the second guide vane group 301 is contracted along the radial direction, wherein the second guide vane group 301 is composed of a plurality of second guide vanes 301a having the same shape and structure, and the second guide vanes 301a act as fins, so that the heat exchange effect between the rotor cooling air and the disk is enhanced;

[0046] The air inlet of each turbine second-stage moving blade 103a corresponds to two second guide vanes 301a.

[0047] It should be noted that each second guide vane 301a has two adjacent second guide vanes 301a, and the two second guide vanes 301a acting on the air inlet of the same turbine second-stage moving blade 103a with one adjacent second guide vane 301a are called a grouped guide vane, and together with another adjacent second guide vane 301a are called an adjacent guide vane group.

[0048] Furthermore, the second guide vane 301a includes a second air inlet end 301a-1 and a second air outlet end 301a-3, and the thickness of the second air inlet end 301a-1 is greater than the thickness of the second air outlet end 301a-3, wherein the second air inlet end 301a-1 is an end away from the air inlet of the second-stage turbine blade 103a, and the air inlet ends of adjacent guide vane groups are in contact, so that cooling air can only enter the internal cavity of each blade through the contraction channel formed by the second guide vane, thereby cooling the blade.

[0049] It should be noted that each second air inlet end 301a-1 and the second-stage impeller disk 103 of the turbine are provided with corresponding countersunk holes, and the two are connected by bolts. The thickness of the second air inlet end 301a-1 is greater than the thickness of the second air outlet end 301a-3, so that the bolts will not be exposed, and further the outer side of the second-stage partition 102 can match the shape of the second guide vane 301a.

[0050] Preferably, the thickness of the second air inlet end 301a-1 is greater than the thickness of the second air outlet end 301a-3. The countersunk hole is provided at the second air inlet end 301a-1 to ensure the connection strength of the bolts. At the same time, the position of the bolt connection is provided at the second air inlet end 301a-1, so that when the angle of the second guide vane 301a is adjusted, the second air inlet end 301a-1 only needs to rotate a very small angle to achieve a larger change in the area of ​​the contraction flow channel at the air outlet end of the grouped guide vanes. Furthermore, adjusting the angle can change the minimum cross-sectional area of ​​the contraction flow channel, thereby adjusting the cooling air flow of each blade.

[0051] Furthermore, the second-stage partition 102 includes a base 102a, a group of protruding wings 102b symmetrically arranged on the base 102a, and a first comb tooth 102c arranged on the outer surface of the upper end of the protruding wings 102b.

[0052] Furthermore, a group of mounting grooves 102d are formed at the connection between a group of protruding wings 102b and the base 102a, and the two mounting grooves 102d are respectively adapted to the bosses of the corresponding first-stage turbine impeller disc 101 or the second-stage turbine impeller disc 103, wherein the first-stage disc and the second-stage disc are connected to the second-stage partition 102 by bolts.

[0053] Further, the sealing assembly 400 includes a second-stage sealing ring 401 and a second-stage sealing ring cooling air hole 402;

[0054] The second-stage sealing ring 401 includes a second groove 401a disposed opposite to the top of the extended wing 102b, and a second comb tooth 401b disposed at the second groove 401a, wherein the first comb tooth 102c and the second comb tooth 401b are disposed opposite to each other.

[0055] It should be noted that the second-stage sealing ring 401 is a hollow structure, which reduces weight while ensuring that the cooling air at the outlet of the inner cavity of the stationary blade fully cools the second-stage sealing ring 401. The first comb teeth 102c and the second comb teeth 401b are arranged to form a comb tooth sealing structure for reducing cold air leakage.

[0056] It should be further explained that the comb teeth sealing structure is only provided on the second-stage partition 102 and the second-stage sealing ring 401, and no sealing structure is provided in the internal cooling channel formed by the second-stage partition 102 and the second-stage sealing ring 401, so as to ensure that the cooling air fully cools the partition and the sealing ring. In addition, since the temperature and pressure of the mainstream gas decrease step by step along the flow direction, the sealing density of the comb teeth at the rear of the turbine first-stage impeller disk 101 is less than the sealing density of the comb teeth at the front of the turbine second-stage impeller disk 103, so as to ensure that the outflow rate of cold air at the rear of the first-stage impeller disk is greater than the outflow rate of cold air at the front of the second-stage impeller disk, so as to ensure that the intrusion of the mainstream gas is effectively prevented, and the leakage of cold air at the disk cavity seal is minimized.

[0057] Preferably, the density of the comb teeth sealing structure varies along the flow direction, so that the sealing cold air outflow rate between different stages is different, the sealing cold air outflow rate of the front stage is large, and the sealing cold air outflow rate of the rear stage is small, which not only ensures the sealing effect, but also minimizes the mixing intensity of the sealing cold air and the mainstream fuel gas, reduces flow losses, and improves turbine efficiency.

[0058] Furthermore, the top end of the second-stage sealing ring 401 is connected to the second-stage turbine vane 104 via a hanging ear and a slot.

[0059] Furthermore, the inner cavity cross-section of the second-stage sealing ring 401 is in the shape of an inverted soil.

[0060] It should be noted that the cooling air at the outlet of the inner cavity of the stator blade cools the second-stage sealing ring 401 and is then discharged into the cooling channel formed between the second-stage sealing ring 401 and the second-stage partition plate 102 through the second-stage sealing ring cooling air hole 402, fully cooling the second-stage partition plate 102 and the second-stage sealing ring 401, and is then discharged after being sealed by the second-stage partition plate 102 and the comb teeth on the outside of the second-stage sealing ring 401, thereby preventing the intrusion of mainstream fuel gas from the outside and cooling the second-stage stator blade edge plate and the third-stage moving blade edge plate.

[0061] When in use, high-pressure cooling air from the compressor enters the rotor impeller, and the first cooling air enters the chamber between the first-stage impeller 101 of the turbine and the outer side of the second-stage partition 102 through the cooling holes on the first-stage impeller 101 of the turbine. Under the action of the centrifugal force of the high-speed rotation of the rotor impeller, the high-pressure cooling air passes through the contraction type flow passage formed by the first guide vane 201a and the second-stage partition 102, and the high-pressure cooling air enters the inner cavity of the blade through the tenon groove of the impeller and the cooling holes at the root of the first-stage impeller, so as to cool the first-stage impeller. It should be noted that the principle of cooling the second-stage impeller is the same as that of cooling the first-stage impeller, which will not be elaborated here.

[0062] After cooling the second-stage stator blades, the second-stage stator blade cooling air passes through the second-stage stator blade inner cavity and enters the chamber formed by the second-stage stator blade 104 and the second-stage sealing ring 401 of the turbine. After cooling the second-stage sealing ring 401, the second-stage sealing ring cooling hole 402 enters the cooling chamber between the second-stage sealing ring 401 and the second-stage partition 102. After sufficient convection heat exchange in the cooling channel formed by the second-stage partition 102 and the second-stage sealing ring 401, the cooling air passes through the second-stage sealing ring 401 and the comb tooth sealing structure on the outer end surface of the second-stage partition 102 to enter the mainstream, preventing the mainstream gas from invading, and cooling the stator blade edge plate at the same time.

[0063] In summary, the beneficial effect of a gas turbine turbine disc cavity sealing cooling device of the present invention is that the guide component is set up, which can produce a suction effect on the cooling air entering the inner cavity of the moving blade under the action of the centrifugal force of the rotating wheel, and a contraction flow channel is formed between the guide vanes, thereby increasing the cooling air flow rate, strengthening the heat exchange effect between the cooling air and the moving blades, and improving the cooling efficiency. Furthermore, the guide vane and the wheel are connected by bolts, and the minimum cross-sectional area of ​​the contraction flow channel formed by the guide vane is changed by adjusting the angle of the guide vane, so that the cooling air flow entering the inner cavity of each moving blade can be adjusted.

[0064] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A gas turbine turbine disc cavity sealing cooling device, characterized in that: include, A first flow guide component (200) disposed between a first-stage impeller disk (101) of a turbine and a second-stage partition plate (102), and a second flow guide component (300) disposed between a second-stage impeller disk (103) of a turbine and a second-stage partition plate (102), wherein the second-stage partition plate (102) is a symmetrical hollow structure; It also includes a sealing assembly (400) disposed inside the second-stage partition (102).

2. The gas turbine turbine disc chamber sealing cooling device according to claim 1, characterized in that: The first guide assembly (200) comprises a first guide vane group (201) arranged in a circumferential array along the first-stage impeller disk (101) of the turbine, the first guide vane group (201) being contracted in a radial direction, wherein the first guide vane group (201) is composed of a plurality of first guide vanes (201a) having the same shape and structure; The air inlet of each turbine first-stage moving blade (101a) corresponds to two of the first guide vanes (201a).

3. The gas turbine turbine disc chamber seal cooling device according to claim 2, characterized in that: The first guide vane (201a) comprises a first air inlet end (201a-1) and a first air outlet end (201a-2), and the thickness of the first air inlet end (201a-1) is greater than the thickness of the first air outlet end (201a-2), wherein the first air inlet end (201a-1) is an end away from the air inlet of the first-stage turbine blade (101a).

4. The gas turbine turbine disc chamber seal cooling device according to claim 3, characterized in that: The second guide assembly (300) comprises a second guide vane group (301) arranged in a circumferential array along the second-stage impeller disk, the second guide vane group (301) being contracted along the radial direction, wherein the second guide vane group (301) is composed of a plurality of second guide vanes (301a) having the same shape and structure; The air inlet of each turbine second-stage moving blade (103a) corresponds to two of the second guide vanes (301a).

5. The gas turbine turbine disc chamber seal cooling device according to claim 4, characterized in that: The second guide vane (301a) comprises a second air inlet end (301a-1) and a second air outlet end (301a-3), and the thickness of the second air inlet end (301a-1) is greater than the thickness of the second air outlet end (301a-3), wherein the second air inlet end (301a-1) is an end away from the air inlet of the second stage moving blade (103a) of the turbine.

6. The gas turbine turbine disc chamber seal cooling device according to any one of claims 1 to 5, characterized in that: The second-stage partition (102) comprises a base (102a), a group of protruding wings (102b) symmetrically arranged on the base (102a), and first comb teeth (102c) arranged on the outer surface of the upper end of the protruding wings (102b).

7. The gas turbine turbine disc chamber seal cooling device according to claim 6, characterized in that: A group of mounting grooves (102d) are formed at the connection between a group of the extending wings (102b) and the base (102a), and two of the mounting grooves (102d) are respectively adapted to the corresponding bosses of the first-stage impeller disc (101) of the turbine or the second-stage impeller disc (103) of the turbine.

8. The gas turbine turbine disc chamber seal cooling device according to claim 7, characterized in that: The sealing assembly (400) comprises a second-stage sealing ring (401) and a second-stage sealing ring cooling air hole (402); The second-stage sealing ring (401) comprises a second groove (401a) arranged opposite to the top end of the extended wing (102b), and a second comb tooth (401b) arranged at the second groove (401a), wherein the first comb tooth (102c) and the second comb tooth (401b) are arranged opposite to each other.

9. The gas turbine turbine disc chamber seal cooling device according to claim 8, characterized in that: The top end of the second-stage sealing ring (401) is connected to the second-stage stationary blade (104) of the turbine via a hanging ear and a slot.

10. The gas turbine turbine disc chamber seal cooling device according to claim 9, characterized in that: The inner cavity cross section of the second-stage sealing ring (401) is in the shape of an inverted soil.

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