Contact damping and contact rigidity test experimental device and method

Abstract

The invention belongs to the technical field of contact rigidity and contact damping testing, and provides a contact damping and contact rigidity testing experiment device and method.The contact damping and contact rigidity testing experiment device comprises a fixing assembly and a testing assembly, and the fixing assembly comprises a bladed disc fixing base which is used for being fixedly connected with a tested bladed disc structural part; the knocking assembly comprises an experiment table, the top of the experiment table is hinged to the top end of a vertical connecting force rod, a vibration excitation piece is arranged at the bottom end of the vertical connecting force rod, the vertical connecting force rod is used for driving the vibration excitation piece to move towards the tested blade disc structural part, and the vibration excitation piece is used for hammering the side wall of the tested blade disc structural part; the vibration measurement assembly is used for measuring a vibration signal after the detected bladed disc structural member is hammered; and the upper computer is used for obtaining a corresponding damping attenuation curve according to a signal measured by the vibration measurement assembly. According to the invention, the blade-bladed disc contact stiffness can be directly measured more conveniently, and the contact damping value is obtained through a method of combining experiments and simulation.

Description

Technical Field

[0001] The invention belongs to the technical field of contact stiffness and contact damping testing, and in particular relates to a contact damping and contact stiffness testing experimental device and method. Background Art

[0002] According to the statistical analysis of blade accidents of steam turbine generator sets, the average direct economic loss caused by each blade accident is as high as RMB 10 million. Therefore, higher and higher requirements are placed on the safety and reliability of blades. There are many reasons for blade damage. If we distinguish from the mechanism of occurrence, 60%-80% of the damage is caused by vibration. It can be seen that if we want to improve the reliability of steam turbine operation, especially large steam turbines, we must first solve the problem of blade vibration failure. In the study of blade vibration reduction, the study of contact stiffness and contact damping between the blade and the blade disk is one of the most complex problems. Obtaining accurate contact stiffness values ​​can provide theoretical basis and technical support for the vibration reduction upgrade of turbine blades, and it also has important academic research and engineering application value. Summary of the invention

[0003] The purpose of the present invention is to provide a contact damping and contact stiffness test experimental device and method to solve the above-mentioned problems, so as to achieve a more convenient direct measurement of the blade-blade contact stiffness, obtain the contact damping value by combining experiments and simulations, and obtain the damping coefficient while also being able to perform simulation verification on it.

[0004] To achieve the above object, the present invention provides the following solution: a contact damping and contact stiffness test experimental device, comprising:

[0005] A fixing assembly, comprising a blade disc fixing seat, wherein the blade disc fixing seat is used to fix and connect the blade disc structure to be tested;

[0006] A striking assembly, comprising a test bench, the top of which is hinged with a top end of a vertical connecting force rod, the bottom end of which is provided with a vibration excitation member, the vertical connecting force rod being used to drive the vibration excitation member to move in the direction of the blade disk structure being tested, and the vibration excitation member being used to hammer the side wall of the blade disk structure being tested;

[0007] A vibration measuring component, which is used to measure the vibration signal of the blade disk structure under test when the blade disk structure under test is hammered and vibrated by the vibration excitation component;

[0008] A host computer is used to obtain a corresponding damping attenuation curve according to the signal measured by the vibration measurement component.

[0009] Preferably, a boss is fixedly connected to the top of the side wall of the blade disc fixing seat, and a stud is horizontally fixedly connected to the side of the boss away from the blade disc fixing seat, the stud passes through the center of the blade disc structure to be measured, and a large locking nut is detachably connected to the end of the stud away from the boss, and the large locking nut is used to fix the blade disc structure to be measured to the blade disc fixing seat.

[0010] Preferably, the vibration excitation component includes a horizontal connecting force rod, one end of which is connected to the vertical connecting force rod via a distance adjusting component, and the other end of the horizontal connecting force rod is fixedly connected to a copper head via a pressure sensor, and the distance adjusting component is used to adjust the distance between the copper head and the blade disk structure being measured.

[0011] Preferably, the distance adjusting member includes a connecting sleeve fixedly connected to the bottom of the vertical connecting force rod, a fastening bolt is threadedly connected to the side wall of the connecting sleeve, the threaded end of the fastening bolt is located in the connecting sleeve, and the threaded end of the fastening bolt is rotatably connected to an arc-shaped pressure plate, and the end of the horizontal connecting force rod away from the copper head is slidably connected between the inner wall of the connecting sleeve and the arc-shaped pressure plate.

[0012] Preferably, the vibration measurement assembly includes a laser vibrometer fixedly connected to the experimental table and a reflective tape adhered to the side wall of the blade disk structure to be measured, the reflective tape is arranged corresponding to the laser vibrometer, and a data signal collector is also provided, and the data signal collector is electrically connected to the laser vibrometer.

[0013] A contact damping and contact stiffness test experimental method, the operating steps include:

[0014] Fix the blade disc structure to be tested on the blade disc fixing seat;

[0015] The vertical connecting force rod is pulled up to a position at a first angle to the direction of the plumb line, and the vertical connecting force rod is released, so that the vibration excitation member hammers the side wall of the blade disk structure to be measured, and the damping attenuation curve A is obtained through the vibration measurement component and the host computer calculation;

[0016] A structural modal simulation model based on the interface connection contact model is established for the friction contact surface between the blade and the disk, and the relationship curve between the normal contact stiffness and the damping coefficient is obtained. By adjusting the damping coefficient in the contact simulation model, a simulation curve identical to the damping attenuation curve A is obtained, thereby obtaining a new damping coefficient value.

[0017] The vertical connecting force rod is pulled up to a position with a second angle to the plumb line direction, and the vertical connecting force rod is released, so that the vibration excitation member hammers the side wall of the blade disk structure to be measured, and the damping attenuation curve B is obtained through the vibration measurement component and the host computer calculation;

[0018] Under the structural modal simulation model with updated damping coefficient value, the blade-disk friction surface contact pair is established and its contact stiffness is calculated;

[0019] By adjusting the damping coefficient value of the contact pair, a simulation curve identical to the damping attenuation curve B is obtained, and the damping coefficient value of the corresponding contact pair is taken as the final measurement result.

[0020] Preferably, the calculation formula of contact stiffness is:

[0021]

[0022] Where k is the contact stiffness, R is the pseudo radius of the blade root, E is the Young's modulus of the blade root material, u is the Poisson's ratio of the blade root material, E2 is the Young's modulus of the blade disk groove material, and u2 is the Poisson's ratio of the blade disk groove material.

[0023] Preferably, the first angle is 30 degrees, that is, the vertical connecting force rod is pulled up to a position 30 degrees with the direction of the plumb line, and the second angle is 60 degrees, that is, the vertical connecting force rod is pulled up to a position 60 degrees with the direction of the plumb line.

[0024] Compared with the prior art, the present invention has the following advantages and technical effects:

[0025] 1. The contact damping and contact stiffness test experimental device and method of the present invention can directly measure the contact stiffness more conveniently without the need for repeated data processing. The contact damping value is obtained by combining experiments and simulations, and the damping coefficient can be simulated and verified at the same time.

[0026] 2. The test experimental device of the present invention has a simple working principle, is easy to install, and has a high repeatability. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] 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 will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 A schematic diagram of a test experimental device of the present invention;

[0029] Figure 2 is a schematic diagram of a vibration excitation member of the present invention;

[0030] Figure 3 It is a partial enlarged view of the test bench of the present invention;

[0031] Figure 4It is a schematic diagram of the blade disk fixing seat of the present invention;

[0032] Figure 5 is a schematic diagram of a distance adjustment member of the present invention;

[0033] Among them, 1. The tested blade disc structural parts; 2. Large locking nut; 3. Blade disc fixing seat; 4. Rigid counterweight block; 5. Copper head; 6. Pressure sensor; 7. Horizontal connecting force rod; 8. Vertical connecting force rod; 9. Small locking nut; 10. Experimental bench; 11. Laser vibrometer; 12. Data signal acquisition instrument; 13. Test bench base; 14. Reflective tape; 15. Boss; 16. Stud; 17. Connecting sleeve; 18. Arc pressure plate; 19. Fastening bolts; 20. Reinforcement angle plate. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] Reference Figure 1-Figure 5 The present invention provides a contact damping and contact stiffness test device, comprising:

[0037] A fixing assembly, including a blade disk fixing seat 3, the blade disk fixing seat 3 is used for fixing and connecting the blade disk structure 1 to be tested;

[0038] The striking assembly includes a test bench 10, the top of the test bench 10 is hinged with the top of a vertical connecting force rod 8, the bottom of the vertical connecting force rod 8 is provided with a vibration excitation member, the vertical connecting force rod 8 is used to drive the vibration excitation member to move in the direction of the blade disk structure member 1 to be measured, and the vibration excitation member is used to hammer the side wall of the blade disk structure member 1 to be measured;

[0039] A vibration measuring component, when the blade disk structure 1 under test is hammered and vibrated by the vibration excitation component, the vibration measuring component is used to measure the vibration signal of the blade disk structure 1 under test;

[0040] The host computer is used to obtain the corresponding damping attenuation curve according to the signal measured by the vibration measurement component.

[0041] The main function of the blade disk fixing seat 3 is to fix the blade disk structure 1 under test; the main function of the vertical connecting force rod 8 is to drive the vibration excitation member to swing around the axis at the top of the vertical connecting force rod 8, so that the vibration excitation member can hammer the blade disk structure 1 under test; the main function of the vibration excitation member is to hammer the blade disk structure 1 under the limit of the vertical connecting force rod 8, so that the blade disk structure 1 under test vibrates; the main function of the vibration measurement component is to detect the vibration signal of the blade disk structure 1 under test; the main function of the host computer is to create a simulation model, and analyze and calculate the vibration signal of the vibration measurement component to generate a corresponding damping attenuation curve. On the whole, the measuring device and method of the present invention can more conveniently and directly measure the contact stiffness without repeatedly processing data. The contact damping value is obtained by combining experiments and simulations. While obtaining the damping coefficient, it can also be simulated and verified.

[0042] Further optimization scheme, such as Figure 1 As shown, a test bench base 13 is also provided, and the blade disk fixing seat 3 and the test bench 10 are both fixedly connected to the test bench base 13 .

[0043] Further optimization scheme, such as Figure 1 As shown, the top of the experimental table 10 is connected to the top of the experimental table 10 by a horizontal fixed sliding rod, so that the top of the vertical connecting force rod 8 is hinged to the top of the experimental table 10, and the end of the sliding rod away from the experimental table 10 is threadedly connected with a small locking nut 9. The small locking nut 9 is provided to prevent the vertical connecting force rod 8 from falling off the sliding rod.

[0044] A further optimized solution is that a boss 15 is fixedly connected to the top of the side wall of the blade disk fixing seat 3, and a stud 16 is horizontally fixedly connected to the side of the boss 15 away from the blade disk fixing seat 3. The stud passes through the center of the blade disk structure 1 to be measured, and the end of the stud away from the boss 15 is detachably connected to a large locking nut 2, and the large locking nut 2 is used to fix the blade disk structure 1 to be measured to the blade disk fixing seat 3.

[0045] like Figure 1 and Figure 4 As shown, the center of the measured blade disk structure 1 is sleeved in the stud 16, and the side wall of the measured blade disk structure 1 is made to contact the boss 15, and the large locking nut 2 is tightened at the same time, so that the measured blade disk structure 1 is squeezed between the boss 15 and the large locking nut 2, so as to achieve the effect of fixing the measured blade disk structure 1 on the blade disk fixing seat 3. At the same time, due to the existence of the boss 15, the measured blade disk structure 1 is in a suspended state except for the middle part, so as to ensure that when the measured blade disk structure 1 is excited to vibrate, its vibration process will not be affected.

[0046] Further optimization scheme, such as Figure 1As shown, a reinforcing angle plate 20 is provided on a side of the blade disk fixing seat 3 away from the test bench 10 , and a rigid counterweight block 4 is provided on a side of the reinforcing angle plate 20 away from the blade disk fixing seat 3 .

[0047] A further optimized solution is that the vibration excitation component includes a horizontal connecting force rod 7, one end of the horizontal connecting force rod 7 is connected to the vertical connecting force rod 8 through a distance adjusting component, and the other end of the horizontal connecting force rod 7 is fixedly connected to a copper head 5 through a pressure sensor 6, and the distance adjusting component is used to adjust the distance between the copper head 5 and the blade disk structure 1 to be measured.

[0048] A further optimized solution is that the distance adjusting member includes a connecting sleeve 17 fixedly connected to the bottom of the vertical connecting force rod 8, and a fastening bolt 19 is threadedly connected to the side wall of the connecting sleeve 17. The threaded end of the fastening bolt 19 is located in the connecting sleeve 17, and the threaded end of the fastening bolt 19 is rotatably connected to an arc pressure plate 18. The end of the horizontal connecting force rod 7 away from the copper head 5 is slidably connected between the inner wall of the connecting sleeve 17 and the arc pressure plate 18.

[0049] like Figure 3 and Figure 5 As shown, the fastening bolt 19 is set at the bottom of the connecting sleeve 17. When the vertical connecting force rod 8 is in the plumb direction, if it is necessary to move the copper head 5 in the direction close to the measured blade disk structure 1, the operator only needs to loosen the fastening bolt 19. At this time, a gap appears between the horizontal connecting force rod 7 and the inner wall of the arc pressure plate 18 and the connecting sleeve 17. The operator can pull the horizontal connecting force rod 7 in the direction close to the measured blade disk structure 1 for a certain distance to move the copper head 5 to a suitable distance, and then tighten the fastening bolt 19 to complete the adjustment. Similarly, if it is necessary to move the copper head 5 in the direction away from the measured blade disk structure 1, just pull the horizontal connecting force rod 7 in the direction away from the measured blade disk structure 1. By adjusting the front and rear distance between the copper head 5 and the measured blade disk structure 1, different excitation force sizes can be controlled.

[0050] Further optimization scheme, such as Figure 1 As shown, the vertical connecting force rod 8 can be set to different lengths. By unscrewing the small locking nut 9, the vertical connecting force rod 8 of different lengths can be replaced, thereby changing different hammering points.

[0051] By setting the hammering force and hammering point of the copper head 5 as an adjustable structure, the experimental device of the present invention is not only applicable to the damping coefficient measurement and contact stiffness measurement of the contact pair between the static blade-disk contact surface, but also applicable to the contact damping and contact stiffness measurement of the contact pairs in other fields.

[0052] A further optimized solution is that the vibration measurement assembly includes a laser vibrometer 11 fixedly connected to the test bench 10 and a reflective tape 14 adhered to the side wall of the blade disk structure 1 to be measured, the reflective tape 14 is arranged corresponding to the laser vibrometer 11, and a data signal collector 12 is also arranged, and the data signal collector 12 is electrically connected to the laser vibrometer 11.

[0053] like Figure 3 As shown, when the blade disk structure 1 under test is hammered and vibrated, the reflective tape 14 will be driven to vibrate together. The laser vibrometer 11 can measure the vibration signal of the measuring point covering the reflective tape 14 through the reflective tape, and transmit the detected vibration signal to the data signal acquisition instrument for analysis.

[0054] A contact damping and contact stiffness test experimental method, the operating steps include:

[0055] Fix the blade disc structure 1 to be measured on the blade disc fixing seat 3;

[0056] The vertical connecting force rod 8 is pulled up to a position at a first angle to the direction of the plumb line, and the vertical connecting force rod 8 is released, so that the vibration excitation member hammers the side wall of the blade disk structure member 1 to be measured, and the damping attenuation curve A is obtained through the vibration measurement component and the host computer calculation;

[0057] A structural modal simulation model based on the interface connection contact model is established for the friction contact surface between the blade and the disk, and the relationship curve between the normal contact stiffness and the damping coefficient is obtained. By adjusting the damping coefficient in the contact simulation model, a simulation curve identical to the damping attenuation curve A is obtained, thereby obtaining a new damping coefficient value.

[0058] The vertical connecting force rod 8 is pulled up to a position at a second angle to the direction of the plumb line, and the vertical connecting force rod 8 is released, so that the vibration excitation member hammers the side wall of the blade disk structure member 1 to be measured, and the damping attenuation curve B is obtained through the vibration measurement component and the host computer calculation;

[0059] Under the structural modal simulation model with updated damping coefficient value, the blade-disk friction surface contact pair is established and its contact stiffness is calculated;

[0060] By adjusting the damping coefficient value of the contact pair, a simulation curve identical to the damping attenuation curve B is obtained, and the damping coefficient value of the corresponding contact pair is taken as the final measurement result.

[0061] Further optimizing the scheme, the calculation formula of contact stiffness is:

[0062]

[0063] Where k is the contact stiffness, R is the pseudo radius of the blade root, E1 is the Young's modulus of the blade root material, u1 is the Poisson's ratio of the blade root material, E2 is the Young's modulus of the blade disk groove material, and u2 is the Poisson's ratio of the blade disk groove material.

[0064] According to a further optimization scheme, the first angle is 30 degrees, that is, the vertical connecting force rod 8 is pulled up to a position of 30 degrees with the direction of the plumb line, and the second angle is 60 degrees, that is, the vertical connecting force rod 8 is pulled up to a position of 60 degrees with the direction of the plumb line.

[0065] The experimental process of this embodiment is as follows:

[0066] Step 1: Fix the blade disk structure 1 to be tested on the blade disk fixing seat 3 through the large locking nut 2. At the same time, according to the experimental requirements, hinge the vertical connecting force rod 8 of appropriate length on the experimental table 10, and adjust the relative position between the horizontal connecting force rod 7 and the vertical connecting force rod 8. Ensure that each part is tightly connected to avoid looseness during the experiment.

[0067] Step 2: According to the distance between the components of the device, pull up the horizontal connecting rod 7 to a suitable position, so that the vertical connecting rod 8 forms an angle of about 30 degrees with the plumb line, release the vertical connecting rod 8, and let the copper head 5 connected to the pressure sensor 6 impact the measured blade disk structure 1. At this time, the laser vibrometer 11 can measure the vibration signal of the measuring point covered with the reflective tape 14, and obtain the damping attenuation curve A through the data signal acquisition instrument 12 analysis and computer calculation.

[0068] Step 3: The simulation model of the present invention can be established in the host computer according to the finite element simulation software Abaqus, and a structural modal simulation model based on the interface connection contact model is established for the friction contact surface of the blade-disk to obtain the relationship curve between the normal contact stiffness and the damping coefficient. By adjusting the size of the damping coefficient in the contact simulation model, a simulation curve identical to the damping attenuation curve A is obtained, thereby obtaining a new damping coefficient value, and the new damping coefficient value is synchronously updated to the model.

[0069] Step 4: Pull up the horizontal connecting force rod 7 again, so that the vertical connecting force rod 8 forms an angle of about 60 degrees with the plumb line, release the vertical connecting force rod 8, and let the copper head 5 connected to the pressure sensor 6 impact the measured blade disk structure 1. At this time, the laser vibrometer 11 can measure the vibration signal of the measuring point covered with the reflective tape 14, and the damping attenuation curve B is obtained by analysis and calculation through the data signal acquisition instrument 12.

[0070] Step 5: Under the structural modal simulation model with updated damping coefficient value, establish the blade-disk friction surface contact pair, and calculate the contact stiffness according to the contact stiffness calculation formula.

[0071] Step 6: By adjusting the damping coefficient value of the contact pair, a simulation curve identical to the damping attenuation curve B is obtained. At this time, the damping coefficient value of the corresponding contact pair is taken as the final measurement result.

[0072] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0073] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A contact damping and contact stiffness test device, characterized in that ,include: A fixing assembly, comprising a blade disc fixing seat (3), wherein the blade disc fixing seat (3) is used for fixing and connecting the blade disc structure (1) to be tested; The striking assembly comprises a test bench (10), the top of the test bench (10) being hinged with the top of a vertical connecting force rod (8), the bottom of the vertical connecting force rod (8) being provided with a vibration excitation member, the vertical connecting force rod (8) being used to drive the vibration excitation member to move in the direction of the blade disk structure (1) to be measured, and the vibration excitation member being used to hammer the side wall of the blade disk structure (1) to be measured; A vibration measuring component, wherein when the blade disk structure (1) to be measured is hammered and vibrated by the vibration excitation component, the vibration measuring component is used to measure the vibration signal of the blade disk structure (1) to be measured; A host computer is used to obtain a corresponding damping attenuation curve according to the signal measured by the vibration measurement component.

2. The contact damping and contact stiffness test device according to claim 1, characterized in that: A boss (15) is fixedly connected to the top of the side wall of the blade disk fixing seat (3), and a stud (16) is horizontally fixedly connected to the side of the boss (15) away from the blade disk fixing seat (3), the stud passes through the center of the blade disk structure (1) to be measured, and a large locking nut (2) is detachably connected to the end of the stud away from the boss (15), and the large locking nut (2) is used to fix the blade disk structure (1) to be measured on the blade disk fixing seat (3).

3. The contact damping and contact stiffness test device according to claim 1, characterized in that: The vibration excitation component comprises a horizontal connecting force rod (7), one end of which is connected to the vertical connecting force rod (8) via a distance adjustment component, and the other end of which is fixedly connected to a copper head (5) via a pressure sensor (6), and the distance adjustment component is used to adjust the distance between the copper head (5) and the blade disk structure (1) to be measured.

4. The contact damping and contact stiffness test device according to claim 3, characterized in that: The distance adjustment member comprises a connecting sleeve (17) fixedly connected to the bottom of the vertical connecting force rod (8), a fastening bolt (19) is threadedly connected to the side wall of the connecting sleeve (17), the threaded end of the fastening bolt (19) is located in the connecting sleeve (17), and the threaded end of the fastening bolt (19) is rotatably connected to an arc-shaped pressure plate (18), and one end of the horizontal connecting force rod (7) away from the copper head (5) is slidably connected between the inner wall of the connecting sleeve (17) and the arc-shaped pressure plate (18).

5. The contact damping and contact stiffness test device according to claim 1, characterized in that: The vibration measurement assembly comprises a laser vibrometer (11) fixedly connected to the experimental platform (10) and a reflective tape (14) adhered to the side wall of the blade disk structure (1) to be measured, the reflective tape (14) being arranged corresponding to the laser vibrometer (11), and a data signal acquisition instrument (12) is also arranged, and the data signal acquisition instrument (12) is electrically connected to the laser vibrometer (11).

6. A contact damping and contact stiffness test experimental method, based on the contact damping and contact stiffness test experimental device according to claim 1, characterized in that: The steps include: Fixing the blade disk structure (1) to be measured on the blade disk fixing seat (3); The vertical connecting force rod (8) is pulled up to a position at a first angle to the direction of the plumb line, and the vertical connecting force rod (8) is released, so that the vibration excitation member hammers the side wall of the blade disk structure (1) to be measured, and a damping attenuation curve A is obtained through the vibration measurement component and the host computer calculation; A structural modal simulation model based on the interface connection contact model is established for the friction contact surface between the blade and the disk, and the relationship curve between the normal contact stiffness and the damping coefficient is obtained. By adjusting the damping coefficient in the contact simulation model, a simulation curve identical to the damping attenuation curve A is obtained, thereby obtaining a new damping coefficient value. The vertical connecting force rod (8) is pulled up to a position at a second angle to the plumb line direction, and the vertical connecting force rod (8) is released, so that the vibration excitation member hammers the side wall of the blade disk structure (1) to be measured, and a damping attenuation curve B is obtained through the vibration measurement component and the host computer calculation; Under the structural modal simulation model with updated damping coefficient value, the blade-disk friction surface contact pair is established and its contact stiffness is calculated; By adjusting the damping coefficient value of the contact pair, a simulation curve identical to the damping attenuation curve B is obtained, and the damping coefficient value of the corresponding contact pair is taken as the final measurement result.

7. A contact damping and contact stiffness test experimental method according to claim 6, characterized in that: The calculation formula of contact stiffness is: Where k is the contact stiffness, R is the pseudo radius of the blade root, E1 is the Young's modulus of the blade root material, u1 is the Poisson's ratio of the blade root material, E2 is the Young's modulus of the blade disk groove material, and u2 is the Poisson's ratio of the blade disk groove material.

8. The contact damping and contact stiffness test method according to claim 6, characterized in that: The first angle is 30 degrees, that is, the vertical connecting force rod (8) is pulled up to a position 30 degrees with the plumb line direction, and the second angle is 60 degrees, that is, the vertical connecting force rod (8) is pulled up to a position 60 degrees with the plumb line direction.

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