A rear support structure for testing a low-pressure compressor of a gas turbine

Abstract

The present invention belongs to the technical field of gas turbine testing, and specifically relates to a rear support structure for testing a low-pressure compressor of a gas turbine, including a rear support casing, an extension casing and a wake guide vane; the inner and outer casings of the rear support casing form a rear wake channel; the front end of the outer casing is connected to the rear end of the compressor casing, the front end of the inner casing is connected to the rear end of the extension casing, and the front end of the extension casing is connected between the last stage of stator blades and the rotor comb plate; a front wake channel is formed between the extension casing and the compressor casing, and a wake guide vane is arranged in the front wake channel and is connected to the rear wake channel. The wake channel of this scheme can guide and stabilize the wake sent by the compressor, thereby controlling the total pressure fluctuation and flow fluctuation of the low-pressure compressor outlet gas, reducing the probability of surge due to excessive fluctuation amplitude; effectively simulating the real working environment of the low-pressure compressor.

Description

Technical Field

[0001] The invention belongs to the technical field of gas turbine testing, and in particular relates to a rear support structure for testing a low-pressure compressor of a gas turbine. Background Art

[0002] The compressor is one of the core components of a gas turbine. In order to obtain the overall performance of the compressor, it is often necessary to test the compressor components, measure the stable operating boundary of the compressor, determine the surge margin of the compressor, verify the design performance of the compressor, and obtain parameters such as compressor speed, flow, pressure ratio, efficiency, surge boundary, etc., to provide a test basis for compressor improvement and optimization design.

[0003] The rear support point of the compressor of a gas turbine is often used as a connecting component and a load-bearing component of the compressor. In existing tests, the disassembled rear support point of the compressor is often used as a load-bearing component during compressor testing. However, in a test environment, since a high-pressure compressor will not be installed behind the rear support point of the compressor, it is easy to cause turbulence in the wake of the low-pressure compressor, causing excessive fluctuations in the total pressure and flow rate of the low-pressure compressor outlet gas and surge problems, affecting the accuracy of the test results. At the same time, it also causes a large deviation between the test environment and the actual environment, and in severe cases, damages the tested compressor.

[0004] To this end, it is necessary to design a rear support structure that is closer to the use scenario of the low-pressure compressor and is dedicated to testing. Summary of the invention

[0005] In order to solve the above problems existing in the prior art, the present invention provides a rear support structure for testing a low-pressure compressor of a gas turbine.

[0006] The technical solution adopted by the present invention is:

[0007] A rear support structure for testing a low-pressure compressor of a gas turbine, comprising a rear support casing, an extended casing and a wake guide vane;

[0008] The low-pressure compressor comprises a compressor casing and a compressor rotor; the compressor rotor comprises a rotor grate disc and multi-stage rotor blades, and multi-stage stator blades are arranged inside the compressor casing; the multi-stage rotor blades and the multi-stage stator blades are arranged alternately; the rotor grate disc is arranged behind the last stage rotor blade and is fixedly connected thereto;

[0009] The rear supporting casing includes an outer casing and an inner casing; the outer casing and the inner casing are separated from each other and form a rear wake channel; the front end of the outer casing is connected to the rear end of the compressor casing, the front end of the inner casing is connected to the rear end of the extension casing, and the front end of the extension casing is connected between the last stage stator blades and the rotor comb plate; a front wake channel is formed between the extension casing and the compressor casing, and a wake guide vane is arranged in the front wake channel and is connected to the rear wake channel.

[0010] As an alternative or supplement to the above-mentioned rear support structure: an embedding groove is provided on the outer side wall of the extended casing, the inner end of the wake guide vane is inserted into the embedding groove and fixed by a screw, and the outer end of the wake guide vane is connected to the outer casing.

[0011] As an alternative or supplement to the above rear support structure:

[0012] As an alternative or supplement to the above-mentioned rear support structure: an avoidance ring groove is provided on the inner side wall of the front end of the compressor casing, and when the inner end of the wake guide vane is pulled out of the embedding groove, the outer end of the wake guide vane extends into the avoidance ring groove; the avoidance ring groove is a step groove structure to facilitate the wake guide vane to move forward out of the extended casing.

[0013] As an alternative or supplement to the above-mentioned rear support structure: the compressor rotor also includes a rear shaft neck, which is located at the rear end center of the compressor rotor; the rear support structure also includes an inner support plate and a bearing seat, the inner support plate is connected to the inner side of the inner casing, the bearing seat is connected to the inner side of the inner casing, and the inner side of the bearing seat is connected to the rear shaft neck through a bearing.

[0014] As an alternative or supplement to the above-mentioned rear support structure: a support front cavity is formed between the compressor rotor, the extended casing, the inner support plate, and the bearing seat; a pressure measuring tube is connected to the inner support plate, and the pressure measuring tube is used to detect the air pressure in the support front cavity.

[0015] As an alternative or supplement to the above-mentioned rear support structure: a front comb teeth sealing ring and a front comb teeth sealing seat are arranged in front of the bearing, the front comb teeth sealing ring is sleeved on the rear shaft neck, the front comb teeth sealing seat is fixed on the bearing seat, and the front comb teeth sealing ring and the front comb teeth sealing seat cooperate with each other in comb teeth sealing.

[0016] As an alternative or supplement to the above-mentioned rear support structure: a bearing cavity casing is connected to the central rear side of the inner support plate; a rear comb teeth sealing ring and a rear comb teeth sealing seat are arranged behind the bearing, the rear comb teeth sealing ring is sleeved on the rear journal, the rear comb teeth sealing seat is fixed on the bearing cavity casing, the rear comb teeth sealing ring and the rear comb teeth sealing seat cooperate with each other in a comb teeth seal; a bearing cavity is arranged on the inner side of the bearing cavity casing, and the bearing cavity is connected to a lubricating oil source through an oil supply pipe.

[0017] As an alternative or supplement to the above-mentioned rear support structure: a support rear cavity is formed between the rear support structure and the rear end of the rear axle neck, and an air supply pipe is arranged in the support rear cavity, and the air supply pipe is connected to the air source to pressurize the support rear cavity.

[0018] As an alternative or supplement to the above-mentioned rear support structure: an exhaust casing is connected to the rear end of the rear support casing, an exhaust channel is arranged in the exhaust casing, and the exhaust channel is connected to the rear wake channel.

[0019] The beneficial effects of the present invention are:

[0020] 1. After the rear support structure of this scheme is connected to the low-pressure compressor, a wake channel can be formed. The wake channel can guide and stabilize the wake sent by the compressor, thereby effectively controlling the total pressure fluctuation and flow fluctuation of the gas at the outlet of the low-pressure compressor, and reducing the probability of surge due to excessive fluctuation amplitude;

[0021] 2. The front end of the extended casing in this scheme can be connected with the stator blades and the rotor comb disc, effectively simulating the real working environment of the low-pressure compressor and reducing the surge problem caused by the leakage of the low-pressure compressor tail flow to other cavities. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below.

[0023] Figure 1 It is the usage status diagram of the rear support structure in this scheme;

[0024] Figure 2 It is a structural schematic diagram of the rear support structure in this scheme;

[0025] Figure 3 It is a structural schematic diagram of some components of the low-pressure compressor.

[0026] In the figure: 1-rear support casing; 101-outer casing; 102-inner casing; 103-hollow connecting column; 104-rear wake channel; 2-pressure measuring tube; 3-oil supply pipe; 4-air supply pipe; 5-wake guide vane; 6-extension casing; 7-inner support plate; 8-bearing cavity casing; 9-bearing seat; 10-rear journal; 11-bearing; 12-exhaust casing; 121-exhaust channel; 13-connecting bolts; 14-rotor blades; 15-stator blades; 16-compressor casing; 17-front comb seal seat; 18-front comb seal ring; 19-rear comb seal ring; 20-support front cavity; 21-support rear cavity; 22-rear comb seal seat; 23-rotor comb disc. DETAILED DESCRIPTION

[0027] The technical solution in this embodiment will be clearly and completely described below in conjunction with the accompanying drawings. The described embodiments are only some of the embodiments, not all of them. Based on the embodiments in this solution, all other embodiments obtained by ordinary technicians in this field without making creative work are within the protection scope of this solution.

[0028] like Figures 1 to 3 As shown, this embodiment designs a rear support structure for testing a low-pressure compressor of a gas turbine, including a rear support casing 1, an extension casing 6, a wake guide vane 5 and other components.

[0029] The low-pressure compressor includes a compressor casing 16, a compressor rotor, a rear journal 10 and other components; wherein the compressor rotor includes a rotor grate disc 23 and multi-stage rotor blades 14, and the multi-stage rotor blades 14 are arranged in sequence from front to back. The rotor grate disc 23 is arranged behind the last stage rotor blade 14 and is fixedly connected thereto. In the actual use of the rotor grate disc 23, the rotor grate disc 23 is used to cooperate with the compressor rear fulcrum of the gas turbine for grate sealing. Multi-stage stator blades 15 are arranged on the inner side of the compressor casing 16, and the multi-stage stator blades 15 are arranged in sequence from front to back, and the multi-stage rotor blades 14 and the multi-stage stator blades 15 are arranged alternately; so that part of the stator blades 15 are located between adjacent rotor blades 14, and the stator blades 15 of the last stage are located behind the rotor blades 14 of the last stage, and the stator blades 15 of the last stage are also arranged at intervals on the radial outer side of the rotor grate disc 23. The rear end of the compressor casing 16 extends beyond the stator blades 15 .

[0030] The rear support casing 1 includes an outer casing 101, an inner casing 102, an extension casing 6, and a hollow connecting column 103. The outer casing 101 and the inner casing 102 are separated from each other and form a rear wake channel 104. The hollow connecting column 103 is arranged inside the rear wake channel 104 and connected between the outer casing 101 and the inner casing 102 to achieve connection and support between the outer casing 101 and the inner casing 102. The hollow connecting column 103 is wing-shaped to facilitate air diversion.

[0031] The front end of the outer casing 101 is connected to the rear end of the compressor casing 16. Specifically, the rear end of the compressor casing 16 and the front end of the outer casing 101 are both provided with flanges, and the compressor casing 16 and the outer casing 101 are fixed by connecting bolts 13 passing through the flanges of the two. The front end of the inner casing 102 is connected to the rear end of the extension casing 6. The front end of the extension casing 6 is connected between the last stage stator blade 15 and the rotor grate plate 23. The rotor grate plate 23 can be sealed with the grate of the extension casing 6. A front wake channel can be formed between the extension casing 6 and the compressor casing 16. A wake guide vane 5 is provided in the front wake channel and is connected to the rear wake channel 104. The wake guide vane 5 can guide the airflow in the front wake channel, thereby guiding and stabilizing the wake sent by the low-pressure compressor, effectively controlling the total pressure fluctuation and flow fluctuation of the gas at the outlet of the low-pressure compressor, and reducing the probability of surge due to excessive fluctuation amplitude. The front end of the extended casing 6 can be connected with the stator blades 15 and the rotor comb disc 23, effectively simulating the real working environment of the low-pressure compressor and reducing the surge problem caused by the leakage of the low-pressure compressor tail flow to other cavities.

[0032] An embedding groove is provided on the outer side wall of the extended casing 6, and the inner end of the wake guide blade 5 is inserted into the embedding groove and fixed by screws, and the outer end of the wake guide blade 5 is connected with the outer casing 101. An avoidance ring groove is provided on the inner side wall of the front end of the compressor casing 16, and when the inner end of the wake guide blade 5 is pulled out of the embedding groove, the outer end of the wake guide blade 5 extends into the avoidance ring groove; the avoidance ring groove is a step groove structure, so that the wake guide blade 5 can be moved forward out of the extended casing 6. Through the cooperation of the embedding groove and the avoidance ring groove, the wake guide blade 5 can be easily disassembled and replaced separately, reducing the workload during disassembly and assembly, and different wake guide blades 5 can be replaced according to the speed range required for testing the low-pressure compressor, so that the test scene is closer to the actual use scene.

[0033] The rear journal 10 is located at the rear end center of the compressor rotor; the rear support structure also includes an inner support plate 7 and a bearing seat 9, the inner support plate 7 is connected to the inner side of the inner casing 102, the bearing seat 9 is connected to the inner side of the inner casing 102, and the inner side of the bearing seat 9 is connected to the rear journal 10 through a bearing 11. In this embodiment, a single bearing 11 is used to support the compressor rotor, which can reduce the difficulty of installing the compressor rotor during testing, and also reduce the difficulty of production and manufacturing of the rear support structure; in addition, the rear support structure supports the compressor rotor at a single point, which can expose problems such as the dynamic balance performance of the compressor rotor more quickly and improve the test efficiency.

[0034] A support front cavity 20 is formed between the compressor rotor, the extended casing 6, the inner support plate 7, and the bearing seat 9; a pressure measuring tube 2 is connected to the inner support plate 7, and the pressure measuring tube 2 is used to detect the air pressure in the support front cavity 20. The support front cavity 20 can simulate the cavity between the compressor rotor and the rear support point of the compressor of the gas turbine itself, so as to realize the simulation and estimation of the cavity between the compressor rotor and the rear support point of the compressor in the real environment by measuring the parameters such as the cavity pressure of the support front cavity 20. The pressure measuring tube 2 passes through the inner cavity of the hollow connecting column 103 and leads out of the rear support casing 1.

[0035] A front comb teeth sealing ring 18 and a front comb teeth sealing seat 17 are arranged in front of the bearing 11. The front comb teeth sealing ring 18 is sleeved on the rear shaft neck 10, and the front comb teeth sealing seat 17 is fixed on the bearing seat 9. The front comb teeth sealing ring 18 and the front comb teeth sealing seat 17 cooperate with each other in a comb teeth sealing manner to separate the bearing cavity from the support front cavity 20, thereby simulating the real lubrication environment of the bearing 11.

[0036] A bearing cavity casing 8 is connected to the center rear side of the inner support plate 7; a rear comb seal ring 19 and a rear comb seal seat 22 are arranged behind the bearing 11, the rear comb seal ring 19 is sleeved on the rear journal 10, the rear comb seal seat 22 is fixed on the bearing cavity casing 8, and the rear comb seal ring 19 and the rear comb seal seat 22 are mutually comb-sealed; a bearing cavity is arranged on the inner side of the bearing cavity casing 8, and the bearing cavity is connected to the lubricating oil source through the oil supply pipe 3. The oil spray nozzle at the bearing seat 9 can spray oil to the bearing 11. The oil supply pipe 3 passes through the inner cavity of the hollow connecting column 103 and leads out of the rear support casing 1.

[0037] A support rear cavity 21 is formed between the rear support structure and the rear end of the rear journal 10, and an air supply pipe 4 is provided in the support rear cavity 21, and the air supply pipe 4 is connected to the air source to pressurize the support rear cavity 21. The support rear cavity 21 can simulate the cavity between the high-pressure compressor and the rear support point of the compressor, and through the pressurization of the air supply pipe 4, the air pressure in the cavity between the high-pressure compressor and the rear support point of the compressor can be closer to the actual working condition of the actual gas turbine, and at the same time, the smooth oil leakage between the rear comb tooth sealing ring 19 and the front comb tooth sealing seat 17 can be reduced.

[0038] An exhaust casing 12 is connected to the rear end of the rear support casing 1. The exhaust casing 12 also has an inner and outer side, so that an exhaust channel 121 is formed in the exhaust casing 12. The exhaust channel 121 is connected to the rear wake channel 104, so as to further stabilize the pressure of the air exhausted by the compressor, thereby improving the similarity between the test environment and the actual use environment.

[0039] The above embodiments are merely examples for the purpose of clarifying the description, and are not intended to limit the implementation methods; it is not necessary and impossible to list all implementation methods exhaustively. However, obvious changes or modifications derived therefrom are still within the scope of protection of the present technology.

Claims

1. A rear support structure for testing a low-pressure compressor of a gas turbine, characterized in that: It comprises a rear support casing (1), an extension casing (6) and a wake guide vane (5); The low-pressure compressor comprises a compressor casing (16) and a compressor rotor; the compressor rotor comprises a rotor grate disc (23) and multi-stage rotor blades (14); the inner side of the compressor casing (16) is provided with multi-stage stator blades (15); the multi-stage rotor blades (14) and the multi-stage stator blades (15) are arranged alternately; the rotor grate disc (23) is arranged behind the last stage rotor blade (14) and is fixedly connected thereto; The rear support casing (1) comprises an outer casing (101) and an inner casing (102); the outer casing (101) and the inner casing (102) are separated from each other and form a rear wake channel (104); the front end of the outer casing (101) is connected to the rear end of the compressor casing (16), the front end of the inner casing (102) is connected to the rear end of the extension casing (6), and the front end of the extension casing (6) is connected between the last stage stator blade (15) and the rotor comb plate (23); a front wake channel is formed between the extension casing (6) and the compressor casing (16), and a wake guide vane (5) is arranged in the front wake channel and is connected to the rear wake channel (104); An embedding groove is provided on the outer side wall of the extended casing (6), the inner end of the wake guide blade (5) is inserted into the embedding groove and fixed by a screw, and the outer end of the wake guide blade (5) is connected to the outer casing (101); an avoidance ring groove is provided on the inner side wall of the front end of the compressor casing (16), when the inner end of the wake guide blade (5) is pulled out of the embedding groove, the outer end of the wake guide blade (5) extends into the avoidance ring groove; the avoidance ring groove is a step groove structure, so that the wake guide blade (5) can be moved forward out of the extended casing (6); The compressor rotor further comprises a rear journal (10), the rear journal (10) being located at the rear end center of the compressor rotor; the rear support structure further comprises an inner support plate (7) and a bearing seat (9), the inner support plate (7) being connected to the inner side of the inner casing (102), the bearing seat (9) being connected to the inner side of the inner casing (102), and the inner side of the bearing seat (9) being connected to the rear journal (10) via a bearing (11); A support front cavity (20) is formed between the compressor rotor, the extended casing (6), the inner support plate (7), and the bearing seat (9); a pressure measuring tube (2) is connected to the inner support plate (7), and the pressure measuring tube (2) is used to detect the air pressure in the support front cavity (20); The rear end of the compressor casing (16) and the front end of the outer casing (101) are both provided with flanges, and the compressor casing (16) and the outer casing (101) are fixed by connecting bolts (13) passing through the flanges of the two. Two front grate seal rings (18) and two front grate seal seats (17) are arranged in front of the bearing (11), a chamber is formed between the two front grate seal rings (18), the front grate seal rings (18) are sleeved on the rear journal (10), the front grate seal seats (17) are fixed on the bearing seat (9), and the front grate seal rings (18) and the front grate seal seats (17) are in grate seal cooperation with each other; A bearing cavity casing (8) is connected to the rear center of the inner support plate (7); two rear comb tooth sealing rings (19) and two rear comb tooth sealing seats (22) are arranged behind the bearing (11); a chamber is formed between the two rear comb tooth sealing rings (19); the rear comb tooth sealing ring (19) is sleeved on the rear journal (10); the rear comb tooth sealing seat (22) is fixed on the bearing cavity casing (8); the rear comb tooth sealing ring (19) and the rear comb tooth sealing seat (22) are mutually engaged in a comb tooth sealing; a bearing cavity is arranged on the inner side of the bearing cavity casing (8); the bearing cavity is connected to a lubricating oil source through an oil supply pipe (3).

2. The rear support structure for testing a gas turbine low-pressure compressor according to claim 1, characterized in that: A support rear cavity (21) is formed between the rear support structure and the rear end of the rear journal (10), and an air supply pipe (4) is arranged in the support rear cavity (21). The air supply pipe (4) is connected to an air source to pressurize the support rear cavity (21).

3. The rear support structure for testing a gas turbine low-pressure compressor according to claim 1 or 2, characterized in that: An exhaust casing (12) is connected to the rear end of the rear support casing (1), an exhaust passage (121) is provided in the exhaust casing (12), and the exhaust passage (121) is communicated with the rear wake passage (104).

Images