Platform for testing labyrinth seal robustness in non-rigid rotor system

Abstract

The invention discloses a labyrinth seal robustness test platform in a non-rigid rotor system, and relates to the technical field of gas turbine engines. Comprising an axial displacement mechanism, a variable stiffness system and a labyrinth element test section, the variable stiffness system is installed at the top of the axial displacement mechanism, and the labyrinth element test section is connected with the axial displacement mechanism through a main shaft connection installation plate. According to the invention, axial position adjustment and axial displacement deviation injection are realized through the axial displacement mechanism, continuous variable stiffness adjustment is realized through the variable stiffness system, the test section is used for carrying out principle tests of different comb tooth configurations, and injection of comb tooth gap deviation is realized by installing the electric heating sheet on the surface of the comb tooth disc. A test system is formed by the axial displacement, the radial clearance and the aerodynamic force, so that the test bed can be used for researching the influence of axial displacement-radial clearance-aerodynamic force coupling on the sealing performance of the labyrinth in a non-rigid rotor system and researching the response rule of axial displacement or radial clearance deviation on a sealing system.

Description

Technical Field

[0001] The invention relates to the technical field of gas turbine engines, and in particular to a test platform for the robustness of comb tooth sealing in a non-rigid rotor system. Background Art

[0002] Comb seal (or labyrinth seal) is a typical rotary-static seal structure. It is widely used in secondary flow air systems of gas turbine engines due to its simple structure, reliability and high efficiency sealing performance. It performs multiple functions in the secondary flow air system, such as bearing cavity lubricating oil sealing, rotor axial force adjustment, and wheel rim gas sealing.

[0003] As a complex system composed of multiple components, the gas turbine engine has the characteristics of "strong integrity". During operation, the rotor system is subjected to both thermal loads (thermal stress) and mechanical loads (centrifugal force, aerodynamic force, etc.), which results in radial centrifugal deformation and thermal deformation, as well as axial tensile deformation. As a part of the rotor system, the radial centrifugal deformation and thermal deformation of the comb seal will change the sealing gap of the comb teeth, and the axial tensile deformation will change the axial relative position of the comb disc and the sealing ring. The changes in the sealing gap and axial relative position affect the sealing performance of the comb teeth, and thus affect various functions in the air system, such as sealing and rotor axial force adjustment.

[0004] However, current experimental studies on the sealing characteristics of grate teeth usually only focus on the grate teeth themselves, and conduct research on the sealing performance optimization of the grate teeth under the condition that the inlet and outlet boundaries of the grate teeth remain unchanged, and pay more attention to the sealing performance of the grate teeth under a single working condition and a single gap / axial displacement. However, the actual performance of the grate teeth in the system environment is not considered, nor is the impact of gap changes or axial displacement changes on the grate teeth sealing performance and system response. This may cause the grate teeth sealing flow to be highly sensitive to gap changes or axial displacements in the system environment (the robustness of the grate teeth sealing is poor), which may lead to the problem that the rotor axial force is sensitive to gap changes or axial displacements.

[0005] Most of the existing test bench designs or test methods for comb tooth seals are based on rigid assumptions or near-rigid assumptions, and are unable to simulate the axial displacement in a real rotor system to influence the comb tooth seal performance. At the same time, they can only study the influence of a single factor change of axial displacement or radial clearance on the comb tooth seal performance. It is impossible to conduct experimental research on the influence of axial displacement, radial clearance, aerodynamic force, etc. on the comb tooth seal performance under coupling effects, and it is impossible to evaluate the robustness of the comb tooth seal during operation. Summary of the invention

[0006] The main purpose of the present invention is to provide a test platform for the robustness of grate seals in a non-rigid rotor system to overcome the problems existing in the prior art.

[0007] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0008] A test platform for the robustness of a grate seal in a non-rigid rotor system comprises an axial displacement mechanism, a variable stiffness system and a grate element test section, wherein the grate element test section is connected to the axial displacement mechanism via a main shaft connection mounting plate;

[0009] The axial displacement mechanism is used to adjust the axial position of the rotor system and to simulate the axial displacement of the rotor system caused by aerodynamic forces. The variable stiffness system utilizes the compressibility of the gas to achieve continuous adjustment of the gas spring stiffness, thereby achieving continuous adjustment of the axial stiffness of the entire rotor system. The comb element test section is used to test comb discs with different tooth structures.

[0010] Further, the axial displacement mechanism includes a fixed base, a mounting base, a servo motor, a reducer, a coupling, a movable base, a force sensor, a screw nut connector, a screw nut, a ball screw, a bearing support seat, a linear guide rail, a first slider group and a second slider group;

[0011] The mounting base is fixedly mounted on the top of the fixed base, the servo motor is fixedly mounted on the top of the mounting base, the reducer and the coupling are sequentially arranged at the output end of the servo motor, one end of the ball screw is mounted on the output end of the coupling, and the other end is rotatably connected to the bearing support seat, the bearing support seat is fixedly mounted on the top of the fixed base, the lead screw nut is threadedly connected to the ball screw, the lead screw nut connector is mounted on the end of the lead screw nut, the movable base is fixedly mounted on the top of the lead screw nut connector, the linear guide is fixedly mounted on the top of the mounting base, the first slider group and the second slider group are both slidably connected to the linear guide, the second slider group is connected to the bottom of the movable base, the first slider group is connected to the bottom sides of the variable stiffness system, the two ends of the variable stiffness system are connected to the top of the movable base through the mounting fixing flange, and the comb tooth element test section is mounted on the top of the mounting base.

[0012] Furthermore, a bearing mounting seat is sleeved on the outer side of the middle part of the ball screw, a first rolling bearing is installed between the ball screw and the bearing mounting seat, and a second rolling bearing is installed between the end of the ball screw and the bearing support seat.

[0013] Furthermore, for the axial position adjustment of the rotor system, the servo motor outputs power to the ball screw through the reducer and the coupling, the rotation of the ball screw drives the screw nut to move axially, the screw nut drives the movable base plate to move axially through the screw nut connecting piece, and the movable base plate slides on the linear guide rail through the second slider group, thereby changing the axial position of the variable stiffness system and adjusting the axial position of the test section rotor.

[0014] Further, the variable stiffness system includes a gas spring, a first mounting flange, a second mounting flange, a gas charging and discharging pipeline, a pressure gauge, a reinforcing rib, a spindle connection mounting plate, a slider mounting plate, and a force sensor mounting plate;

[0015] The gas spring is connected to one end of the gas charging and discharging pipeline, and the other end of the gas charging and discharging pipeline is connected to the barometer. The first mounting flange and the second mounting flange are arranged at both ends of the gas spring, the main shaft connection mounting plate is arranged on the outside of the first mounting flange, the force sensor mounting plate is arranged on the outside of the second mounting flange, the force sensor is installed on the inner wall of the force sensor mounting plate, the two ends of the reinforcing rib are connected between the main shaft connection mounting plate and the force sensor mounting plate, and the two reinforcing ribs are respectively located on both sides of the gas spring, the slider mounting plate is installed at the bottom of the reinforcing rib, the main shaft connection mounting plate and the force sensor mounting plate, and the first slider group is installed at the bottom of the slider mounting plate.

[0016] Furthermore, for the axial displacement change of the rotor system caused by aerodynamic force, the aerodynamic axial force of the comb element test section is transmitted to the gas spring through the main shaft connection mounting plate, reinforcing ribs and force sensor mounting plate, thereby simulating the axial displacement change of the rotor system under the action of aerodynamic force.

[0017] Furthermore, the comb tooth element test section includes a main mounting shaft, a linear bearing, a universal seal for the shaft, a linear bearing gland, a universal seal pressure plate, an electric heating plate, an air intake cavity, a radial displacement sensor, a sealing ring, a temperature control annular cavity, an end cover, a comb tooth disc, an axial displacement sensor, an exhaust system interface, a sensor lead hole, and a locking nut;

[0018] The air inlet cavity is mounted on the mounting base plate, the sealing ring is mounted on the side of the air inlet cavity, the grate disc is located inside the sealing ring, the end cover is mounted on the side of the sealing ring away from the air inlet cavity, one end of the main mounting shaft is mounted on the side of the main shaft connecting mounting plate, and the other end passes through the air inlet cavity, the grate disc and the end cover, linear bearings are arranged between the main mounting shaft and the air inlet cavity, and between the main mounting shaft and the end cover, a shaft universal seal, a linear bearing pressure cover and a universal seal pressure plate are arranged at the end of the linear bearing, a grate disc mounting seat is arranged between the main mounting shaft and the grate disc and is fixed with a locking nut;

[0019] The electric heating plate is arranged on the surface of the comb disk, an annular air intake cavity is arranged in the air intake cavity, the radial displacement sensor is arranged on the outer wall of the sealing ring, the temperature control annular cavity is arranged inside the sealing ring, the axial displacement sensor is arranged on the inner wall of the end cover, the exhaust system interface is arranged on the outer wall of the end cover, and the sensor lead hole is arranged on the main mounting shaft.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] The test bench of the present invention breaks through the rigidity assumption or near rigidity assumption in the traditional test design, and simulates the rigidity of the rotor system through the designed variable rigidity system, and has the continuous adjustment capability;

[0022] Secondly, the combination of the axial displacement mechanism and the variable stiffness system can not only realize the active adjustment of the axial displacement by the tester, namely the axial initial position adjustment (operation performed before the test) and the axial displacement deviation injection (operation performed during the test), but can also be used to simulate the axial displacement changes of the rotor system caused by aerodynamic forces;

[0023] Finally, axial position adjustment and axial displacement deviation injection are achieved through the axial displacement mechanism, continuous variable stiffness adjustment is achieved through the variable stiffness system, comb element test is carried out through the comb element test section, and the test system has the ability to inject radial clearance deviation into the comb teeth. The test system composed of the three enables the test bench to carry out research on the influence of axial displacement-radial clearance-aerodynamic coupling on the comb sealing performance in a non-rigid rotor system, as well as research on the response law of the sealing system to axial displacement or radial clearance deviation, which can well support the stability / robustness design of comb sealing elements. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is the general assembly drawing of the test platform of the present invention.

[0025] Figure 2 It is a three-dimensional structural schematic diagram of the axial displacement mechanism and variable stiffness system of the present invention.

[0026] Figure 3 It is a side view of the axial displacement mechanism and variable stiffness system of the present invention.

[0027] Figure 4 It is a cross-sectional view of the axial displacement mechanism and variable stiffness system of the present invention at AA.

[0028] Figure 5 It is a schematic diagram of the structure of the mobile substrate of the present invention.

[0029] Figure 6 It is a front view of the screw rod nut connecting piece of the present invention.

[0030] Figure 7 It is a top view of the screw nut connector of the present invention.

[0031] Figure 8 Schematic diagram of the variable stiffness system components of the present invention.

[0032] Fig. 9 It is a schematic diagram of the force direction of the variable stiffness system and the connection of the present invention.

[0033] Fig.10 It is an assembly diagram of the test section of the comb tooth element of the present invention.

[0034] Fig.11 It is a front view of the test section of the comb tooth element of the present invention.

[0035] Fig.12 It is a cross-sectional view of the test section BB of the comb tooth element of the present invention.

[0036] Among them, 1-axial displacement mechanism, 101-fixed base, 102-mounting base, 103-servo motor, 104-reducer, 105-coupling, 106-movable base, 107-first rolling bearing, 108-force sensor, 109-screw nut connector, 110-screw nut, 111-ball screw, 112-bearing support seat, 113-first rolling bearing, 114-linear guide, 115-first slider group, 116-second slider group, 2-variable stiffness system, 201-gas spring, 202-first mounting flange, 203-second mounting flange, 204-gas charging and discharging pipeline, 205-barometer, 206-reinforcement rib, 207-spindle connection mounting plate, 208-slider mounting plate, 20 9-force sensor mounting plate, 3-comb element test section, 301-main mounting shaft, 302-linear bearing, 303-shaft universal seal, 304-linear bearing pressure cover, 305-universal seal pressure plate, 306-electric heating plate, 307-intake cavity, 308-radial displacement sensor, 309-sealing ring, 310-sealing ring temperature control annular cavity, 311-end cover, 312-comb disc, 313-axial displacement sensor, 314-exhaust system interface, 315-sensor lead hole, 316-locking nut, 317-comb disc mounting seat, 318-comb disc mounting accessories, 1061-first bolt hole, 1062-second bolt hole, 1063-third bolt hole, 1091-fourth bolt hole, 1092-fifth bolt hole. DETAILED DESCRIPTION

[0037] The technical solution of the present invention is further described below through the accompanying drawings and embodiments.

[0038] Combination Figures 1 to 12 The present embodiment provides a comb seal robustness test platform in a non-rigid rotor system, comprising an axial displacement mechanism 1, a variable stiffness system 2 and a comb element test section 3, wherein the variable stiffness system 2 is installed on the top of the axial displacement mechanism 1, and the comb element test section 3 is connected to the axial displacement mechanism 1 via a main shaft connection mounting plate 207.

[0039] In this embodiment, the axial displacement mechanism 1 includes a fixed base 101, a mounting base 102, a servo motor 103, a reducer 104, a coupling 105, a movable base 106, a force sensor 108, a screw nut connector 109, a screw nut 110, a ball screw 111, a bearing support seat 112, a linear guide 114, a first slider group 115 and a second slider group 116;

[0040] The mounting substrate 102 is fixedly mounted on the top of the fixed base 101, the servo motor 103 is fixedly mounted on the top of the mounting substrate 102, the reducer 104 and the coupling 105 are sequentially arranged at the output end of the servo motor 103, one end of the ball screw 111 is mounted on the output end of the coupling 105, and the other end is rotatably connected to the bearing support seat 112, the bearing support seat 112 is fixedly mounted on the top of the fixed base 101, the screw nut 110 is threadedly connected to the ball screw 111, and the screw nut connector 109 is mounted on the screw nut 111. 0, the movable base plate 106 is fixedly mounted on the top of the screw nut connector 109, the linear guide rail 114 is fixedly mounted on the top of the mounting base plate 102, the first slider group 115 and the second slider group 116 are both slidably connected to the linear guide rail 114, the second slider group 116 is connected to the bottom of the movable base plate 106, the first slider group 115 is connected to the bottom two sides of the variable stiffness system 2, the two ends of the variable stiffness system 2 are connected to the top of the movable base plate 106 through the mounting fixing flange, and the comb tooth element test section 3 is installed on the top of the mounting base plate 102.

[0041] Preferably, a bearing mounting seat is sleeved on the outer side of the middle part of the ball screw 111, a first rolling bearing 107 is installed between the ball screw 111 and the bearing mounting seat, and a second rolling bearing 113 is installed between the end of the ball screw 111 and the bearing support seat 112.

[0042] In this embodiment, the variable stiffness system 2 includes a gas spring 201, a first mounting flange 202, a second mounting flange 203, a gas charging and discharging pipeline 204, a barometer 205, a reinforcing rib 206, a spindle connection mounting plate 207, a slider mounting plate 208 and a force sensor mounting plate 209;

[0043] The gas spring 201 is connected to one end of the gas charging and discharging pipeline 204, and the other end of the gas charging and discharging pipeline 204 is connected to the barometer 205. The first mounting flange 202 and the second mounting flange 203 are arranged at both ends of the gas spring 201. The spindle connection mounting plate 207 is arranged on the outside of the first mounting flange 202, and the force sensor mounting plate 209 is arranged on the outside of the second mounting flange 203. The force sensor 108 is installed on the inner wall of the force sensor mounting plate 209. The two ends of the reinforcing rib 206 are connected between the spindle connection mounting plate 207 and the force sensor mounting plate 209, and the two reinforcing ribs 206 are respectively located on both sides of the gas spring 201. The slider mounting plate 208 is installed at the bottom of the reinforcing rib 206, the spindle connection mounting plate 207 and the force sensor mounting plate 209, and the first slider group 115 is installed at the bottom of the slider mounting plate 208.

[0044] In this embodiment, the gas spring 201 is connected to the first mounting flange 202 by bolts, and the first mounting flange 202 and the second mounting flange 203 are connected to the first bolt hole 1061 by four bolts; there are three second bolt holes 1062, and the three second bolt holes are connected to the three fifth bolt holes 1092 on the screw nut connector 109 by bolts; the third bolt hole 1063 is used to fix the movable base plate 106 and connect it to the slider on the linear guide rail 114, each slider corresponds to 4 third bolt holes, a total of 4 sliders, corresponding to 16 third bolt holes; the fourth bolt hole 1091 is connected to the corresponding hole position on the screw nut 110 by bolts.

[0045] The movable base plate 106 is connected to the screw nut connector 109 , and then the screw nut connector 109 is connected to the screw nut 110 , so that the connection of these three parts is realized. The gas spring 201 is fixed on the movable base plate 106 through the first mounting flange 202 and the second mounting flange 203 .

[0046] In this embodiment, the comb element test section 3 includes a main installation shaft 301, a linear bearing 302, a shaft universal seal 303, a linear bearing pressure cover 304, a universal seal pressure plate 305, an electric heating plate 306, an air intake cavity 307, a radial displacement sensor 308, a sealing ring 309, a temperature control annular cavity 310, an end cover 311, a comb disc 312, an axial displacement sensor 313, an exhaust system interface 314, a sensor lead hole 315, a locking nut 316 and a comb disc mounting seat 317;

[0047] The air inlet cavity 307 is installed on the mounting base plate 102, the sealing ring 309 is installed on the side of the air inlet cavity 307, the comb disc 312 is located inside the sealing ring 309, the end cover 311 is installed on the side of the sealing ring 309 away from the air inlet cavity 307, one end of the main mounting shaft 301 is installed on the side of the main shaft connecting mounting plate 207, and the other end passes through the air inlet cavity 307, the comb disc 312 and the end cover 311, linear bearings 302 are provided between the main mounting shaft 301 and the air inlet cavity 307, and between the main mounting shaft 301 and the end cover 311, and the ends of the linear bearings 302 are provided with shaft universal seals 303, linear bearing pressure covers 304 and universal seal pressure plates 305, and a comb disc mounting seat is provided between the main mounting shaft 301 and the comb disc 312 and fixed with a locking nut 316;

[0048] The electric heating plate 306 is arranged on the surface of the comb disk 312, an annular air intake cavity is arranged inside the air intake cavity 307, the radial displacement sensor 308 is arranged on the outer wall of the sealing ring 309, the temperature control annular cavity 310 is arranged inside the sealing ring 309, the axial displacement sensor 313 is arranged on the inner wall of the end cover 311, the exhaust system interface 314 is arranged on the outer wall of the end cover 311, and the sensor lead hole 315 is arranged on the main installation shaft 301.

[0049] In this embodiment, the axial displacement mechanism 1 is a mechanical mechanism for adjusting the axial position of the rotor system and simulating the axial displacement of the rotor system caused by aerodynamic forces. During the test, the former axial position adjustment / axial displacement needs to be achieved through the subjective will of the tester, that is, the magnitude of the axial position adjustment is determined by the tester, and the axial position adjustment includes both the adjustment of the axial initial position and the axial displacement applied during the test. This article refers to the change in axial displacement as axial displacement deviation injection; while the axial displacement generated by the latter is the ability or attribute of the test system itself, and the magnitude of the axial displacement is determined by the test conditions.

[0050] Specifically, for adjusting the axial position of the rotor system, the servo motor 103 outputs power to the ball screw 111 through the reducer 104 and the coupling 105. The rotation of the ball screw 111 drives the screw nut 110 to move axially. The screw nut 110 drives the movable base plate 106 to move axially through the screw nut connector 109. The movable base plate 106 slides on the linear guide rail 114 through the second slider group 116, thereby changing the axial position of the variable stiffness system 2. Figure 4 As shown, the position control of the servo motor 103 is used to convert the rotational motion into linear motion, thereby achieving axial position control of the load.

[0051] For the axial displacement change of the rotor system caused by aerodynamic force, the aerodynamic axial force of the comb element test section 3 is transmitted to the gas spring 201 through the main shaft connection mounting plate 207, the reinforcing rib 206 and the force sensor mounting plate 209. Under the action of the force, the piston rod of the gas spring (201) is compressed to generate an axial displacement. The main shaft connection mounting plate 207, the reinforcing rib 206 and the slider mounting plate 208 move axially on the linear guide rail 114 along with the first slider group 115, thereby simulating the axial displacement change of the rotor system under the action of aerodynamic force, wherein the force direction of each component is as follows: Fig. 9 The slider group 115 is mounted on the linear guide rail 114 , and the reinforcing rib 206 , the spindle connection mounting plate 207 , and the force sensor mounting plate 209 are connected to the slider group 115 via the slider mounting plate 208 .

[0052] In this embodiment, the variable stiffness system 2 is a subsystem capable of continuously adjusting the axial stiffness. The working medium of the gas spring 201 includes but is not limited to compressible gases such as air and nitrogen. Figure 8 As shown, the purpose is to utilize the compressibility of gas to achieve continuous adjustment of the stiffness of the gas spring, thereby achieving stiffness adjustment of the entire rotor system.

[0053] In this embodiment, the comb tooth element test section 3 is a subsystem that can test comb tooth discs with different tooth structures.

[0054] Specifically, the gap deviation is injected by thermal deformation. Since the gap is the matching gap between the sealing ring and the comb disc, this test introduces circulating cooling water into the annular cavity inside the sealing ring to ensure that the sealing ring is in a constant temperature environment without thermal deformation or minimizes thermal deformation, and controls the radial deformation of the comb disc by hot air heating or by arranging electric heating plates on the surface of the comb disc, that is, the gap deviation is entirely derived from the deformation of the comb disc.

[0055] In addition, the test section adopts a modular design, and different test requirements can be met by replacing the sealing ring 309 with different structures or the comb tooth plate 312 with different structures.

[0056] Specifically, first, the test bench is divided into three parts (modules), the axial displacement mechanism, the variable stiffness system and the comb element test section. Each part is connected by standard bolts, and each module can be debugged and installed separately by connecting or disconnecting the bolts. Secondly, the test section can carry out different comb tests by replacing sealing rings and comb discs of different configurations. The design requirements for the main body of the sealing ring are the same as those in this test. The specific differences can be reflected in the structure of the steps on the inner ring of the sealing ring, such as no steps or other types of steps; the design requirements for the comb disc are mainly that it can be installed with the comb disc mounting seat and the comb disc accessories, and can be replaced with the same interface.

[0057] In order to reduce the sensitivity of the comb tooth sealing performance to parameter deviations such as radial clearance and axial displacement and improve the robustness of the comb tooth sealing, this embodiment proposes a comb tooth sealing robustness test platform in a non-rigid rotor system. The test platform has active adjustment of the relative position of the comb tooth disk and the sealing ring, and the axial displacement can change with the change of aerodynamic force during the test. At the same time, the test platform has the injection of comb tooth sealing clearance deviation, and can carry out steady-state tests under different boundary conditions, different axial positions, and different sealing clearances for different comb tooth configurations, as well as system transient response tests in the presence of axial displacement deviation and radial clearance deviation.

[0058] The above description is only a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any slight modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A test platform for the robustness of grate seal in a non-rigid rotor system, characterized in that: It comprises an axial displacement mechanism (1), a variable stiffness system (2) and a comb element test section (3), wherein the variable stiffness system (2) is installed on the top of the axial displacement mechanism (1), and the comb element test section (3) is connected to the axial displacement mechanism (1) via a main shaft connection mounting plate (207); The axial displacement mechanism (1) is used to adjust the axial position of the rotor system and to simulate the axial displacement of the rotor system caused by aerodynamic force; the variable stiffness system (2) uses the compressibility of gas to achieve continuous adjustment of the stiffness of the gas spring, thereby achieving continuous adjustment of the axial stiffness of the entire rotor system; the comb element test section (3) is used to test comb discs with different tooth profile structures.

2. A test platform for the robustness of grate seals in a non-rigid rotor system as claimed in claim 1, characterized in that: The axial displacement mechanism (1) comprises a fixed base (101), a mounting base (102), a servo motor (103), a reducer (104), a coupling (105), a movable base (106), a force sensor (108), a screw nut connector (109), a screw nut (110), a ball screw (111), a bearing support seat (112), a linear guide rail (114), a first slider group (115) and a second slider group (116); The mounting substrate (102) is fixedly mounted on the top of the fixed base (101); the servo motor (103) is fixedly mounted on the top of the mounting substrate (102); the reducer (104) and the coupling (105) are sequentially arranged at the output end of the servo motor (103); one end of the ball screw (111) is mounted on the output end of the coupling (105); the other end is rotatably connected to the bearing support seat (112); the bearing support seat (112) is fixedly mounted on the top of the fixed base (101); the screw nut (110) is threadedly connected to the ball screw (111); and the screw nut connector (109) is mounted on the screw nut (111). 0), the movable base plate (106) is fixedly mounted on the top of the screw nut connector (109), the linear guide rail (114) is fixedly mounted on the top of the mounting base plate (102), the first slider group (115) and the second slider group (116) are both slidably connected to the linear guide rail (114), the second slider group (116) is connected to the bottom of the movable base plate (106), the first slider group (115) is connected to the bottom of the variable stiffness system (2), the two ends of the variable stiffness system (2) are connected to the top of the movable base plate (106) through mounting fixing flanges, and the comb tooth element test section (3) is mounted on the top of the mounting base plate (102).

3. A test platform for the robustness of grate seals in a non-rigid rotor system as claimed in claim 2, characterized in that: A bearing mounting seat is sleeved on the outer side of the middle portion of the ball screw (111), a first rolling bearing (107) is installed between the ball screw (111) and the bearing mounting seat, and a second rolling bearing (113) is installed between the end of the ball screw (111) and the bearing support seat (112).

4. A test platform for the robustness of grate seals in a non-rigid rotor system as claimed in claim 2, characterized in that: For adjusting the axial position of the rotor system, the servo motor (103) outputs power to the ball screw (111) through the reducer (104) and the coupling (105); the rotation of the ball screw (111) drives the screw nut (110) to move axially; the screw nut (110) drives the movable base plate (106) to move axially through the screw nut connector (109); the movable base plate (106) slides on the linear guide rail (114) through the second slider group (116), thereby changing the axial position of the variable stiffness system (2) and adjusting the axial position of the test section rotor.

5. A test platform for the robustness of grate seals in a non-rigid rotor system as claimed in claim 2, characterized in that: The variable stiffness system (2) comprises a gas spring (201), a first mounting flange (202), a second mounting flange (203), a gas charging and discharging pipeline (204), a pressure gauge (205), a reinforcing rib (206), a main shaft connection mounting plate (207), a slider mounting plate (208) and a force sensor mounting plate (209); The gas spring (201) is connected to one end of the gas charging and discharging pipeline (204), and the other end of the gas charging and discharging pipeline (204) is connected to the barometer (205). The first mounting flange (202) and the second mounting flange (203) are arranged at two ends of the gas spring (201). The main shaft connecting mounting plate (207) is arranged on the outside of the first mounting flange (202). The force sensor mounting plate (209) is arranged on the outside of the second mounting flange (203). The force sensor (108) is installed On the inner wall of the force sensor mounting plate (209), the two ends of the reinforcing rib (206) are connected between the main shaft connection mounting plate (207) and the force sensor mounting plate (209), and the two reinforcing ribs (206) are respectively located on both sides of the gas spring (201), the slider mounting plate (208) is installed at the bottom of the reinforcing rib (206), the main shaft connection mounting plate (207) and the force sensor mounting plate (209), and the first slider group (115) is installed at the bottom of the slider mounting plate (208).

6. A test platform for the robustness of grate seals in a non-rigid rotor system as claimed in claim 5, characterized in that: For the change of axial displacement of the rotor system caused by aerodynamic force, the aerodynamic axial force of the comb element test section (3) is transmitted to the gas spring (201) through the main shaft connection mounting plate (207), the reinforcing ribs (206) and the force sensor mounting plate (209). Under the action of the force, the piston rod of the gas spring (201) is compressed to generate axial displacement. The mounting plate (207), the reinforcing ribs (206) and the slider mounting plate (208) move axially on the linear guide rail (114) along with the first slider group (115), thereby simulating the axial displacement and the change of axial displacement generated by the rotor system under the action of aerodynamic force.

7. A test platform for the robustness of grate seals in a non-rigid rotor system as claimed in claim 2, characterized in that: The comb element test section (3) comprises a main mounting shaft (301), a linear bearing (302), a shaft universal seal (303), a linear bearing pressure cover (304), a universal seal pressure plate (305), an electric heating plate (306), an air intake cavity (307), a radial displacement sensor (308), a sealing ring (309), a temperature control annular cavity (310), an end cover (311), a comb disc (312), an axial displacement sensor (313), an exhaust system interface (314), a sensor lead hole (315), a locking nut (316), a comb disc mounting seat (317) and a comb disc accessory (318); The air inlet cavity (307) is mounted on the mounting base plate (102), the sealing ring (309) is mounted on the side of the air inlet cavity (307), the grate tooth plate (312) is located inside the sealing ring (309), the end cover (311) is mounted on the side of the sealing ring (309) away from the air inlet cavity (307), one end of the main mounting shaft (301) is mounted on the side of the main shaft connecting mounting plate (207), and the other end passes through the air inlet cavity (307), the grate tooth plate (312) and the end cover (311) A linear bearing (302) is provided between the toothed disc (312) and the end cover (311), between the main installation shaft (301) and the air inlet cavity (307), and between the main installation shaft (301) and the end cover (311); a shaft universal seal (303), a linear bearing pressure cover (304) and a universal seal pressure plate (305) are provided at the end of the linear bearing (302); and a locking nut (316) is used to fix the main installation shaft (301) and the comb toothed disc (312); The electric heating plate (306) is arranged on the surface of the comb tooth disk (312), the air intake cavity (307) is arranged inside the comb tooth element test section (3), the radial displacement sensor (308) is arranged on the outer wall of the sealing ring (309), the temperature control annular cavity (310) is arranged inside the sealing ring (309), the axial displacement sensor (313) is arranged on the inner wall of the end cover (311), the exhaust system interface (314) is arranged on the outer wall of the end cover (311), and the sensor lead hole (315) is arranged on the main installation shaft (301).

Images