Fan-shaped blade grid test device capable of independently adjusting radial clearance and axial clearance of single blade

Abstract

The invention discloses a fan-shaped blade grid test device capable of independently adjusting radial and single-blade axial gaps, belongs to the technical field of pneumatic tests of turbomachinery, and aims to solve the key problem that the axial and radial composite gap effect cannot be systematically researched and single-blade installation errors cannot be simulated on the same test bed in the prior art. The test device comprises a test section, wherein the test section is provided with an upper end wall, a lower end wall and a plurality of test blades mounted between the upper end wall and the lower end wall; the test device further comprises a radial adjusting mechanism used for continuously adjusting radial gaps between blade crowns of all the test blades and the upper end wall; the axial adjusting mechanism is used for independently and continuously adjusting the axial position of each test blade; wherein the radial adjusting mechanism and the axial adjusting mechanism are two sets of physically separated independent systems and are respectively configured in different areas of the test section.

Description

Technical Field

[0001] This invention relates to the field of pneumatic testing technology for turbomachinery, and specifically to a precision gap adjustment device for a fan-shaped blade test bench. Background Technology

[0002] In the design of advanced steam turbines and other turbomachinery, the long blades of the low-pressure cylinder often employ a crowned moving blade design. To prevent frictional collisions between the moving blades and the cylinder, a certain radial clearance must be maintained between the blade crown and the cylinder. Simultaneously, an axial clearance exists between the blade crown and the upstream stationary components. The existence of these clearances inevitably leads to some steam working fluid leaking directly from these gaps without performing work through the moving blade passage, resulting in complex gap leakage flow. The interaction between the leaked flow and the mainstream flow causes severe aerodynamic losses and may even induce unsteady vibrations. Gap leakage is one of the key factors affecting the efficiency and safety of steam turbines.

[0003] Given the complex phenomena behind leakage flow in long blade gaps, researchers typically employ aerodynamic testing with fan-shaped cascades to investigate the leakage flow mechanism and validate gap structure design schemes. Existing fan-shaped cascade gap testing techniques have the following main limitations:

[0004] (1) The gap adjustment method is complicated. The existing blade cascade test device mainly relies on replacing the gap structure to adjust the gap. It can only carry out aerodynamic tests under specific discrete gaps. If a large number of aerodynamic tests under different gaps are required, it is necessary to produce matching gap adjustment components. This leads to a surge in production costs, especially the installation and commissioning costs of the test. In practice, it is generally impossible to carry out large-sample variable gap sector blade cascade tests.

[0005] (2) The gap adjustment dimension is singular. The existing fan-shaped blade test device can usually only change one of the radial gap or the axial gap. It is difficult to achieve simultaneous independent adjustment of the two gaps. Only a small number of aerodynamic tests under specific gap combinations can be carried out. Therefore, it is impossible to systematically study the combined influence of the two gaps on the leakage flow.

[0006] (3) It cannot simulate the differences of a single blade. The blade cascade of traditional test devices is usually treated as an integral component for adjustment. It is impossible to independently fine-tune the axial position of a single blade. Therefore, it cannot simulate the effect of blade axial installation position deformation caused by processing and assembly errors on the aerodynamic performance of long blades in reality.

[0007] Therefore, there is an urgent need in this field for a new type of experimental device that can simultaneously and independently make precise and continuous adjustments to the radial clearance and the axial clearance of a single blade, and can also easily replace the corresponding clearance structure components, so as to efficiently test and simulate the gap flow problem of crowned long blades. Summary of the Invention

[0008] To address the critical challenge of existing technologies being unable to systematically study the combined axial and radial clearance effects and simulate single-blade installation errors on a single test bench, this invention provides a fan-shaped blade cascade test device that can independently adjust the radial and axial clearances of a single blade.

[0009] The present invention discloses a fan-shaped blade cascade test device with independently adjustable radial and axial clearances of single blades. The fan-shaped blade cascade test device 100 includes a test section 20, the test section 20 having an upper end wall 30, a lower end wall 22, and a plurality of test blades 21 installed between the two.

[0010] The sector-shaped blade cascade test device 100 further includes:

[0011] A radial adjustment mechanism is used to continuously adjust the radial clearance between the crown 42 of all the test blades 21 and the upper end wall 30;

[0012] An axial adjustment mechanism is provided for independently and continuously adjusting the axial position of each of the test blades 21.

[0013] The radial adjustment mechanism and the axial adjustment mechanism are two physically separate independent systems, respectively configured in different areas of the test section 20.

[0014] Preferably, the radial adjustment mechanism includes:

[0015] Adjustment frame 31 fixed above the test section;

[0016] A floating module 33 that can be radially movably disposed within the upper end wall 30;

[0017] And a radial drive assembly mounted on the adjustment frame 31 is used to drive the floating module 33 to generate radial displacement;

[0018] The inner wall of the floating module 33 and the blade crown 42 form an adjustable radial gap.

[0019] Preferably, the radial drive assembly includes:

[0020] At least three radially arranged lead screws 36;

[0021] In addition, a synchronous belt drive system 35 is provided to ensure that all radial lead screws 36 rotate synchronously;

[0022] The radial lead screw 36 is fixed at one end and mounted on the adjustment frame 31. It is driven to connect with the threaded engagement structure on the floating module 33. By adjusting the radial position of the floating module 33, the required radial clearance can be set arbitrarily.

[0023] Preferably, the axial adjustment mechanism includes:

[0024] An axially elongated groove 221 is formed on the lower end wall 22 for each of the test blades 21;

[0025] In addition, N sets of independent single-blade drive assemblies 23, each set of single-blade drive assemblies 23 is installed outside the lower end wall 22 and is connected to the root of one of the test blades 21 to independently drive the blade to move within the axial long groove 221.

[0026] Preferably, the single-blade drive assembly 23 includes a lead screw 231, a nut seat 234 that cooperates with the lead screw 231, and a handwheel 232 that drives the lead screw 231 to rotate.

[0027] Preferably, the handwheel 232 is provided with a dial 233 for accurately indicating and setting the axial position of the test blade 21.

[0028] Preferably, a shaped sealing ring 222 for dynamic sealing is provided between the contact interface between the root of the test blade 21 and the axial groove 221.

[0029] Preferably, the inner wall surface of the floating module 33 is provided with a detachable and replaceable steam seal tooth insert 41, which is a smooth surface and has a double or triple tooth structure.

[0030] Preferably, the crown 42 of the test blade 21 is a detachable and replaceable modular component, and the crown 42 has a smooth surface, a double tooth, or a triple tooth structure.

[0031] The beneficial effects of this invention are:

[0032] 1. Decoupling and expansion of clearance adjustment dimension: Through two completely independent adjustment mechanisms, radial and axial, the radial clearance and the axial position of a single blade were completely, independently, continuously and precisely controlled for the first time on a fan-shaped blade test device. This greatly expanded the experimental parameter space and provided the possibility for systematic research on the shaft-radial composite clearance effect and the blade axial misalignment effect.

[0033] 2. Improved the fidelity of the experiment and its engineering guidance value: It can quantitatively simulate and study the inconsistency of the axial position of a single blade caused by machining and assembly errors (i.e., axial stacking variance). The research results have high reference value for guiding actual engineering design and assembly tolerance formulation.

[0034] 3. Modular structure improves the flexibility and economy of the test system: Key components (such as floating modules, steam seal teeth, and blade crowns) adopt a modular design, which can be easily replaced according to test needs. There is no need to manufacture complete components for every parameter combination, which greatly expands the test range and reduces test costs. Attached Figure Description

[0035] Figure 1 This is a schematic diagram showing the position of the test device described in the embodiment of the present invention within the fan-shaped blade cascade test piece.

[0036] Figure 2 This is a three-dimensional structural schematic diagram of the fan-shaped blade cascade test section according to an embodiment of the present invention.

[0037] Figure 3 This is a three-dimensional structural schematic diagram of the axial adjustment mechanism in an embodiment of the present invention.

[0038] Figure 4 yes Figure 3 A schematic diagram showing the relationship between the lower and middle endwalls and the root of the blade.

[0039] Figure 5 yes Figure 3 Detailed magnified view of the irregularly shaped sealing ring at the root of the test blade.

[0040] Figure 6 This is a three-dimensional structural schematic diagram of the radial adjustment mechanism in an embodiment of the present invention.

[0041] Figure 7 yes Figure 6 Exploded view of the radial adjustment mechanism.

[0042] Figure 8 This is a schematic diagram of the modular design of the gas seal teeth in an embodiment of the present invention, wherein... Figure 8 (a) is a smooth surface. Figure 8 (b) is a double-tooth structure. Figure 8 (c) is a three-tooth structure.

[0043] Figure 9 This is a schematic diagram of the blade structure.

[0044] Figure 10 This is a schematic diagram of the modular crown in an embodiment of the present invention, wherein... Figure 10 (a) is a smooth surface. Figure 10 (b) is a double-tooth structure. Figure 10 (c) is a three-tooth structure.

[0045] Figure label:

[0046] 100: Sector-shaped blade cascade test apparatus;

[0047] 20: Test section; 201: Inlet flange; 21: Test blade;

[0048] 22: Lower end wall; 221: Axial long groove; 222: Irregular seal ring; 23: Single blade drive assembly; 231: Trapezoidal lead screw; 232: Handwheel; 233: Dial; 234: Square lead screw nut seat; 235: Drive slider; 236: Connecting pin.

[0049] 30: Upper end wall; 31: Adjusting frame; 311: Radial connecting stud; 312: Positioning sleeve; 32: Upper end wall body; 321: Guide groove; 33: Floating module; 331: Guide rib; 34: Drive motor; 35: Synchronous belt drive system; 36: Radial lead screw.

[0050] 41: Gas seal tooth insert; 42: Leaf crown. Detailed Implementation

[0051] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0052] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0053] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the scope of the invention.

[0054] Specific Implementation Method 1: The following is combined with... Figures 1 to 10 This embodiment describes a fan-shaped blade cascade test device with independently adjustable radial and axial clearances between individual blades.

[0055] The present invention solves one or more of the following technical problems: (1) the prior art is difficult to achieve the adjustment of different radial or axial clearances under a large number of clearance parameters on the same test device; (2) the prior art is difficult to achieve the independent adjustment of radial and axial clearances on the same test device; (3) the prior art cannot simulate the influence of the inconsistency of the axial position of a single blade on the flow field caused by factors such as assembly errors.

[0056] To address the aforementioned technical problems, this invention provides a fan-shaped blade cascade test device with independently adjustable radial and axial clearances for individual blades. The core idea of ​​this device is to adjust the radial clearance at the top of the blade cascade... The axial position of each of the N test blades , forming the axial position vector Defined as two independently controllable variable systems, and controlled by two completely independent high-precision drive mechanisms to achieve parameter space control. The freedom to adjust.

[0057] I. Overall Structure of the Experimental Apparatus

[0058] See Figure 1 The present invention provides a fan-shaped blade cascade test device 100 with independently adjustable radial and axial clearances of single blades, comprising, in sequence along the airflow direction, a flow guiding and rectifying section (not shown in the figure) and a test section 20. The flow guiding and rectifying section is used to rectify and accelerate the upstream flow, forming a uniform and stable test flow. The test section 20 is connected to the outlet flange of the flow guiding and rectifying section through an inlet flange 201, forming a sealed and continuous annular or fan-shaped flow channel. The inner side of the flow channel is the lower end wall 22, and the outer side of the flow channel is the upper end wall 30.

[0059] The test section 20 consists of a lower end wall 22, an upper end wall 30, multiple test blades 21, and a support and adjustment frame. See the appendix for further details. Figure 2 The supporting adjustment frame includes four radially arranged connecting studs 311 evenly distributed circumferentially, through which the lower end wall 22 is supported. A high-precision machined positioning sleeve 312 is fitted onto each connecting stud 311, the height of which determines the radial installation distance between the upper end wall 30 and the lower end wall 22. The upper end wall 30 is mounted on the top of the positioning sleeve 312. The topmost adjustment frame 31 passes through the connecting studs 311, and all components—the adjustment frame 31, upper end wall 30, positioning sleeve 312, and lower end wall 22—are axially fastened with nuts, forming a stable frame structure with high rigidity and high positioning accuracy. A plurality of (e.g., N) test blades 21 are installed inside this frame, their roots connected to the lower end wall 22, and their tops (the blade crowns 42) forming radial and axial clearances with the inner surface of the upper end wall 30.

[0060] II. Axial Adjustment Mechanism

[0061] Reference Appendix Figure 3 Appendix Figure 4 and attached Figure 5 One of the core innovations of this invention lies in its ability to determine the axial position of each test blade 21. Independent precision control is achieved. This function is realized by an axial adjustment mechanism located on the lower end wall 22. The axial adjustment mechanism includes: an axial groove 221 opened on the lower end wall 22 for each test blade at a corresponding position; and N sets of independent single-blade drive assemblies 23 installed outside the lower end wall 22. Each set of single-blade drive assemblies 23 is connected to the root of a test blade 21 via a connector, and is used to independently drive the test blade 21 to generate a continuous and controllable axial displacement within the axial groove 221, thereby changing and determining the first... ( ) 21 test blades at axial positions The single-blade drive assembly 23 consists of the following components: a trapezoidal lead screw 231, a handwheel 232, a dial 233, a square lead screw nut seat 234, a drive slider 235, and a connecting pin 236. A non-circular sealing ring 222 seals the gap between the root of the test blade 21 and the lower end wall 22. Through the above scheme, this device can achieve quantitative control of the average axial clearance and axial stacking variance.

[0062] The specific implementation includes:

[0063] 1. Blade installation and guidance:

[0064] See attached document Figure 3 On the lower end wall 22, an axial groove 221 is machined corresponding to the root mounting position of each test blade 21. The root of the test blade 21 passes through this axial groove 221. To ensure the stability of the blade during movement, a guide block (not shown in the figure) is designed at the blade root. This guide block forms a sliding pair with the side wall of the axial groove 221, thereby strictly constraining the blade's radial and circumferential degrees of freedom, allowing it to move smoothly only along the airflow direction (axial direction).

[0065] 2. Single blade independent drive:

[0066] See attached document Figure 4 An independent single-blade drive assembly 23 is installed on the outer bottom surface of the lower end wall 22 corresponding to each test blade 21. In this embodiment, the drive assembly 23 preferably adopts a trapezoidal lead screw 231 drive method.

[0067] Drive Actuation: The trapezoidal lead screw 231 is installed with one end fixed and the other end free. Its fixed end is mounted on a bracket on the lower end wall 22 via a bearing-supported base, allowing the lead screw to rotate but restricting its axial movement. A square lead screw nut seat 234 engages with the lead screw 231. The nut seat 234 is securely connected to the root of the test blade 21 via connecting pins 236 and drive sliders 235, among other connecting components.

[0068] Manual adjustment and indication: A handwheel 232 and a scale 233 integrated thereon are installed at the tail end of the lead screw 231. When the handwheel 232 is turned, the lead screw 231 rotates, converting the rotational motion into linear motion of the nut seat 234 through the threaded joint, thereby driving the connected test blade 21 to move precisely within the axial long groove 221. The scale 233 is calibrated, and by reading and controlling its rotation number or division number, the axial position coordinates of each blade can be quantitatively set. This method enables precise control and study of the average axial clearance and the axial stacking variance of the blades (i.e., the axial position difference between blades).

[0069] 3. Dynamic sealing:

[0070] See attached document Figure 5 Since the test blade 21 needs to move within the lower end wall 22, to prevent high-pressure gas from leaking from the blade root, a sealing groove is formed along the blade root profile in the area where the blade root contacts the inner surface of the lower end wall 22. A circularly shaped sealing ring 222 (e.g., a fluororubber O-ring) is installed in the groove. After installation, the sealing ring is pre-compressed, so that it can always fit tightly against the inner surface of the lower end wall 22 when the blade slides axially, achieving a reliable dynamic seal while ensuring minimal sliding friction.

[0071] III. Radial Adjustment Mechanism

[0072] The radial adjustment mechanism of the present invention aims to achieve continuous and overall adjustment of the radial gap between the top of all test blades 21 and the upper end wall 30.

[0073] Reference Appendix Figure 6 and attached Figure 7 The radial adjustment mechanism is used to adjust the radial gap between the test blade crown and the upper end wall. The radial adjustment mechanism includes: an adjustment frame 31 fixed above the test section as an adjustment reference; the upper end wall includes an upper end wall body 32 and a floating module 33 that can move radially. The floating module 33 moves radially through a guide groove 321 opened in the crown of the test blade 21 to change the radial clearance. The displacement of the floating module 33 in other directions is constrained by the structural cooperation between the guide ribs 331 opened on the floating module 33 and the guide groove 321; a drive motor 34 mounted on the adjustment frame drives three radial screws 36 mounted on the floating module 33 by driving a synchronous belt 35, thereby generating continuously changing radial displacement and thus changing and determining the radial clearance. The value of .

[0074] Specific implementation:

[0075] 1. Composite structure and guide of the upper end wall:

[0076] See attached document Figure 6 and 7 The upper end wall 30 is designed as a composite structure. Its upper end wall body 32 is a fixed component with a large through hole in the center. A floating module 33 is installed in this through hole. The inner wall surface (i.e., the lower surface) of the floating module 33 faces and covers the top area of ​​the crown 42 of all test blades 21, and the vertical distance between the two is the radial clearance that needs to be adjusted.

[0077] To ensure the motion accuracy of the floating module 33, at least one (e.g., two mutually perpendicular) guide ribs 331 are machined on its outer wall. Correspondingly, a matching guide groove 321 is formed on the inner wall of the through hole of the upper end wall body 32. The guide ribs 331 and the guide grooves 321 form a high-precision sliding guide pair, which strictly constrains the axial (airflow direction) and circumferential movement of the floating module 33 as well as its rotation around its own axis, ensuring that the floating module 33 can only translate radially (vertically).

[0078] 2. Multi-screw synchronous drive:

[0079] The radial drive assembly uses the adjusting frame 31 as an absolutely stationary reference. A drive motor 34 (e.g., a stepper motor or servo motor) is fixedly mounted on the adjusting frame 31. The output shaft of the drive motor 34 drives a closed-loop synchronous belt 35 via a drive pulley. Three radial lead screws 36 are evenly arranged radially at 120-degree intervals. The upper end of each lead screw 36 is fixed to the adjusting frame 31 via a bearing housing, and the lower end engages with the synchronous belt 35 via a driven pulley. Due to the slip-free transmission characteristics of the synchronous belt 35, the power of the drive motor 34 ensures that the three radial lead screws 36 achieve strictly synchronous rotation.

[0080] Each radial lead screw 36 has its shaft passing through a nut seat (not shown) embedded in the reinforcing structure inside the floating module 33. When the three lead screws rotate synchronously, the rotational motion is converted into a linear driving force along their respective lead screw axes through the nut seats. The radial components of these three driving forces combine into a vertically upward force, driving the entire floating module 33 to smoothly rise and fall along the guide rail. By precisely controlling the rotation angle or number of revolutions of the drive motor 34, millimeter-level or even higher precision control of the radial position of the floating module 33 can be achieved, thereby accurately setting the required radial clearance value.

[0081] IV. Implementation of Modular Expansion

[0082] To expand the experimental research capabilities of this device, key components have adopted a modular design.

[0083] Modular structure of gas seal teeth: refer to the appendix Figure 8 The inner wall of the floating module 33 is designed with a standard interface, which allows for easy installation or replacement of steam seal tooth inserts 41 with different structures. For example, a benchmark test without steam seal teeth (smooth surface) can be conducted, and then the module can be quickly replaced with inserts with various sealing tooth types such as single tooth, double tooth, or labyrinth type, to systematically study the effect of different steam seal structures on suppressing gap leakage flow.

[0084] Leaf crown geometry modularization: see appendix Figure 10The crown 42 at the top of the test blade 21 is also designed as a detachable independent component. Depending on the research needs, crown modules with different profiles, axial lengths, and top shapes (such as flat tops, sloping tops, and grooved tops) can be replaced to study the influence of crown geometry on the generation, development, and mixing loss of leakage vortices.

[0085] V. Test Operation Procedure

[0086] 1. Initialization Setup: Install the test section frame and test blades. Use the handwheel 232 of the axial adjustment mechanism to zero all test blades 21 to a uniform axial reference position. Use the drive motor 34 of the radial adjustment mechanism to adjust the floating module 33 to a larger initial radial clearance position.

[0087] 2. Parameter Setting: According to the test plan, operate the handwheel 232 and dial 233 corresponding to each blade independently to accurately set the axial position of each blade to simulate a specific average axial clearance and stacking variance. At the same time, set the target radial clearance value by controlling the drive motor 34.

[0088] 3. Module replacement: If it is necessary to study the effects of different structures, the test can be paused and the floating module 33 with a specific steam seal tooth insert 41 or the blade crown module 42 with a specific geometry can be easily replaced.

[0089] 4. Conduct the test: Connect the air source and the measurement system, start the test, and measure the aerodynamic performance, flow field structure and leakage flow characteristics of the blade cascade under different combinations of clearance parameters and structural parameters.

[0090] 5. Data Analysis: Systematically analyze the distribution of radial and axial clearances (including differences in single blades) and the combined influence of structural geometry on leakage flow and losses.

[0091] In summary, this invention, through two physically separate and functionally independent precision adjustment mechanisms, achieves for the first time complete decoupling and continuous control of radial clearance and the axial position of each blade on a sector-shaped blade test device. This not only solves the problem of existing technologies having a single adjustment dimension and being unable to simulate individual blade differences, but also greatly expands the testing capabilities through modular design. This device becomes a powerful multivariable parametric research platform, capable of simulating complex clearance states in real turbomachinery with high fidelity, providing an unprecedentedly efficient testing method for in-depth research on clearance leakage mechanisms, optimization of sealing and blade design, and formulation of assembly tolerances.

[0092] While the invention has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that different dependent claims and features described herein can be combined in ways different from those described in the original claims. It is also understood that features described in conjunction with individual embodiments can be used in other described embodiments.

Claims

1. A fan cascade test device capable of independently adjusting radial and single-blade axial clearances, the fan cascade test device (100) comprising a test section (20) having an upper end wall (30), a lower end wall (22) and a plurality of test blades (21) mounted therebetween; characterized in that the fan cascade test device (100) further comprising: a radial adjustment mechanism for continuously adjusting the radial clearance between the shroud (42) of all the test blades (21) and the upper end wall (30); an axial adjustment mechanism for independently and continuously adjusting the axial position of each of the test blades (21); wherein the radial adjustment mechanism and the axial adjustment mechanism are two physically separated independent systems respectively configured in different regions of the test section (20).

2. The independently adjustable radial and single blade axial clearance sector cascade testing device according to claim 1, wherein, the radial adjustment mechanism comprising: an adjustment frame (31) fixed above the test section; a floating module (33) radially movably arranged in the upper end wall (30); and a radial drive assembly mounted on the adjustment frame (31) for driving the floating module (33) to generate radial displacement; the inner wall surface of the floating module (33) and the shroud (42) forming an adjustable radial clearance.

3. A cascade test rig according to claim 2, wherein, the radial drive assembly comprising: at least three radial lead screws (36) arranged in a radial pattern; and a synchronous belt drive system (35) for ensuring synchronous rotation of all radial lead screws (36); the radial lead screws (36) are installed on the adjustment frame (31) in a single-end fixed manner and are drivingly connected with the threaded structure on the floating module (33), so that the required radial clearance can be set by adjusting the radial position of the floating module (33).

4. The independently adjustable radial and single blade axial clearance sector cascade testing device of claim 1, wherein, the axial adjustment mechanism comprising: an axial long slot (221) opened on the lower end wall (22) for each of the test blades (21); and N sets of independent single-blade drive assemblies (23), each set of the single-blade drive assembly (23) being mounted outside the lower end wall (22) and drivingly connected with the root of one of the test blades (21) to independently drive the blade to move in the axial long slot (221).

5. A cascade test rig according to claim 4, wherein, the single-blade drive assembly (23) comprising a lead screw (231), a nut seat (234) matched with the lead screw (231), and a hand wheel (232) driving the lead screw (231) to rotate.

6. A cascade test rig according to claim 5, wherein, the hand wheel (232) is provided with a scale disc (233) for accurately indicating and setting the axial position of the test blade (21).

7. The independently adjustable radial and single-blade axial clearance sector blade row testing apparatus of claim 4 or 5, wherein, a special-shaped sealing ring (222) for dynamic sealing is arranged between the contact interface between the root of the test blade (21) and the axial long slot (221).

8. The independently adjustable radial and single blade axial clearance sector blade row testing apparatus of claim 2 or 3, wherein, a detachable and replaceable steam seal tooth insert (41) is arranged on the inner wall surface of the floating module (33), and the steam seal tooth insert (41) is a smooth surface, double-tooth or triple-tooth structure.

9. The independently adjustable radial and single blade axial clearance sector blade row testing apparatus of claim 1, wherein, the shroud (42) of the test blade (21) is a detachable and replaceable modular component, and the shroud (42) is a smooth surface, double-tooth or triple-tooth structure.

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