Search

CN-122016208-A - Blade dynamic frequency test determination method and device, electronic equipment and test system

CN122016208ACN 122016208 ACN122016208 ACN 122016208ACN-122016208-A

Abstract

The invention discloses a method, a device, electronic equipment and a test system for determining a blade dynamic frequency test, which comprise the steps of collecting blade data to construct a blade finite element model, obtaining blade modal data according to the blade finite element model, setting a load working condition, carrying out harmonic response analysis on the blade finite element model according to the load working condition to obtain unit load frequency response data, wherein the unit load frequency response data comprises real part response data and imaginary part response data, calculating exciting force according to nozzle parameters, calculating nozzle load according to the blade data and the nozzle parameters, comparing and adjusting nozzle setting data according to the nozzle load and the unit load frequency response data, wherein the nozzle setting data comprises the number and the distribution angle of nozzles, obtaining strain amplitude data according to rotor rotation speed, the nozzle load corresponding to the nozzle parameters and the unit load frequency response data, and confirming a test scheme according to the strain amplitude data.

Inventors

  • MA QINGCHAO
  • WEI ZEMING
  • QUE XIAOBIN
  • HE LIU
  • WANG ZHONGCHI

Assignees

  • 中国联合重型燃气轮机技术有限公司

Dates

Publication Date
20260512
Application Date
20260113

Claims (20)

  1. 1. The blade dynamic frequency test determining method is characterized by comprising the following steps of: Acquiring blade data to construct a blade finite element model, and acquiring blade mode data according to the blade finite element model; setting a load working condition, and carrying out harmonic response analysis on the finite element model of the blade according to the load working condition to obtain unit load frequency response data, wherein the unit load frequency response data comprises real part response data and imaginary part response data; Calculating exciting force according to nozzle parameters, calculating nozzle load according to the blade data and the nozzle parameters, and comparing and adjusting nozzle setting data according to the nozzle load and the unit load frequency response data, wherein the nozzle setting data comprises the number and the distribution angle of nozzles; and obtaining strain amplitude data according to the rotor rotating speed, the nozzle load corresponding to the nozzle parameter and the unit load frequency response data, and confirming a test scheme according to the strain amplitude data.
  2. 2. The method of claim 1, wherein the blade mode data includes mode order, natural frequency, and strain ratio.
  3. 3. The method of claim 2, wherein obtaining blade mode data from the blade finite element model comprises: And setting 2 model strain gages on the blade finite element model, and simulating the blade finite element model based on different rotor rotating speeds through simulation analysis software to obtain the modal orders of the blade finite element model under different rotor rotating speeds, wherein the natural frequencies correspond to the modal orders, and strain data and main strain data of the model strain gages.
  4. 4. A method according to claim 3, wherein obtaining blade mode data from the blade finite element model further comprises: And obtaining the strain ratio according to the ratio of the strain data at the model strain gauge and the main strain data.
  5. 5. The method of claim 1, wherein setting a load condition comprises: Setting a load amplitude and a preset frequency, and respectively calculating a chordwise load and a vertical chordwise load according to the load amplitude and the preset frequency.
  6. 6. The method of claim 5, wherein performing harmonic response analysis on the blade finite element model based on the load conditions to obtain unit load frequency response data comprises: and inputting the chord direction load and the perpendicular chord direction load into simulation analysis software to obtain unit load frequency response data, and constructing a load frequency response curve according to the unit load frequency response data.
  7. 7. The method of claim 1, wherein the nozzle parameters include nozzle mass flow, nozzle air flow absolute velocity, and nozzle radius of rotation.
  8. 8. The method of claim 7, wherein the excitation force comprises a chordwise component and a perpendicular chordwise component.
  9. 9. The method of claim 8, wherein calculating the excitation force based on the nozzle parameters comprises: The blade data includes blade length, nozzle airflow angle, and blade mounting angle; calculating the tangential velocity of the radius blade according to the rotating speed of the rotor and the rotating radius of the nozzle; obtaining the relative speed of the air flow according to the tangential speed of the radius blade and the absolute speed of the air flow of the nozzle; and calculating the chord direction component and the perpendicular chord direction component according to the nozzle mass flow, the air flow relative speed calculation, the radius blade tangential speed, the nozzle air flow absolute speed and the blade mounting angle.
  10. 10. The method of claim 9, wherein calculating a nozzle load from the blade data and the nozzle parameters comprises: calculating a nozzle amplitude from the nozzle mass flow and the relative velocity of the air flow; calculating a duration from the rotor speed, the nozzle turning radius, and the vane length; Obtaining a rotational speed fundamental frequency according to the rotational speed of the rotor; The nozzle load is calculated from the nozzle setting data, the nozzle amplitude, the duration, and the rotational speed base frequency.
  11. 11. The method of claim 2, wherein comparing the adjusted nozzle setting data based on the nozzle load and the unit load frequency response data comprises: Based on different nozzle setting data, constructing a load comparison graph according to the frequency by the nozzle load and different modal orders, adjusting the nozzle setting data, enabling the amplitude of the nozzle load to be in a frequency area corresponding to the different modal orders, and storing the nozzle setting data.
  12. 12. The method of claim 9, wherein obtaining strain amplitude data from rotor speed, the nozzle load corresponding to the nozzle parameter, and the unit load frequency response data comprises: And calculating total strain according to the chord direction component, the perpendicular chord direction component, the real part response data and the imaginary part response data, setting a rotating speed interval according to the rotating speed of the rotor, and generating the strain amplitude data according to the rotating speed interval and the total strain.
  13. 13. The method of claim 12, wherein a total strain is calculated from the chordwise component, the perpendicular chordwise component, the real response data, and the imaginary response data as follows: , Wherein the method comprises the steps of In order to achieve the said total strain, For the said chordwise component, For the vertical chordwise component, For the real part response data, For the said imaginary part response data, I is the imaginary part of the resulting complex number, In imaginary units.
  14. 14. The method of claim 13, wherein the real and imaginary expressions of the resulting complex number are as follows: , Wherein the method comprises the steps of I is the imaginary part of the resulting complex number, For the mass flow rate of the nozzle in question, For the relative velocity of the air streams, For an impact load spectrum vector constructed from the unit load frequency response data, For the blade mounting angle in question, In order to be able to achieve a relative velocity angle, For the data of the chordwise component in the real response data, For the data of the perpendicular chordwise component in the real response data, For the data of the chordwise component in the imaginary response data, And data of the vertical chord component in the imaginary response data.
  15. 15. The method of claim 14, wherein the impact load spectral vector is expressed as follows: , Wherein the method comprises the steps of For the impact load spectrum vector, And the unit load frequency response data are sequentially corresponding to the frequency data, and n is an index.
  16. 16. The method of claim 2, wherein validating a test plan based on the strain amplitude data comprises: Judging whether the strain amplitude data corresponding to different frequencies and the modal orders is larger than preset value strain data or not, if so, taking the corresponding nozzle setting data as the test scheme, and if so, adjusting the nozzle setting data to iterate until the obtained strain amplitude data is larger than the preset value strain data.
  17. 17. The utility model provides a blade dynamic frequency test determining device which characterized in that includes: The acquisition and construction module is used for acquiring blade data to construct a blade finite element model, and acquiring blade modal data according to the blade finite element model; The load calculation module is used for setting a load working condition, carrying out harmonic response analysis on the finite element model of the blade according to the load working condition to obtain unit load frequency response data, wherein the unit load frequency response data comprises real part response data and imaginary part response data; The nozzle setting module is used for calculating exciting force according to nozzle parameters, calculating nozzle load according to the blade data and the nozzle parameters, and comparing and adjusting nozzle setting data according to the nozzle load and the unit load frequency response data, wherein the nozzle setting data comprises the number and the distribution angle of nozzles; and the test determining module is used for obtaining strain amplitude data according to the rotor rotating speed, the nozzle load corresponding to the nozzle parameter and the unit load frequency response data, and confirming a test scheme according to the strain amplitude data.
  18. 18. A computer-readable storage medium, characterized in that the computer-readable storage medium comprises a stored computer program, wherein the computer program is executable by an electronic device to perform the method of any one of claims 1 to 16.
  19. 19. A computer program product comprising a computer program, characterized in that the computer program, when executed by a processor, implements the steps of the method as claimed in any one of claims 1 to 16.
  20. 20. An electronic device comprising a memory and a processor, characterized in that the memory has stored therein a computer program, the processor being arranged to execute the method according to any of the claims 1 to 16 by means of the computer program.

Description

Blade dynamic frequency test determination method and device, electronic equipment and test system Technical Field The invention relates to the technical field of research and development of gas turbines, in particular to a method and a device for determining a blade dynamic frequency test, electronic equipment and a test system. Background In the research and development stage of the gas turbine, in order to accurately obtain the natural frequency of the blade in a rotating state, ensure that the resonance frequency of the blade avoids the known excitation frequency, generally, a blade excitation test is carried out on a rotating tester, and the prior art is that an induction device is added on the blade, a nozzle is arranged on a certain height of the blade, the nozzle sprays high-pressure gas or hydraulic oil, a rotor is driven under the condition that the gas/oil continuously excites the blade, the rotating speed is changed, a scanning test is carried out, and the natural frequency of the blade is identified through frequency domain analysis carried out by signals of the induction device. However, the prior art lacks the relevant guidance of test scheme design, the test scheme design is difficult to ensure that the target vibration mode can be accurately excited by each test due to the fact that the number of nozzles, the jet direction of the nozzles, the key test parameters of the vibration excitation position and the like are mainly dependent on experience of testers, in some cases, the key vibration mode can not be excited, the test result is incomplete, the resonance risk of the blade in actual operation can not be accurately estimated, the follow-up blade design and optimization work can lack accurate data support due to the uncertainty and the incompleteness of the test result, the optimization direction of the design stage can not be defined, the resonance problem can not be effectively avoided, the fault risk of the blade in actual operation is increased, in addition, the vibration excitation position is repeatedly adjusted through a trial-and-error method in the test process, the test period is overlong, or the expected test aim can not be achieved, the main reason is that the fast calculation and optimization method for the resonance response of the blade under the test scheme is absent, the conceivable calculation method is fluid-solid calculation, and the calculation technology is not mature and the calculation resource is relatively large due to the fact that the test is carried out under the vacuum environment. The patent document CN118443250A discloses a test method for simulating excitation factors under the rotation state of a blade, which comprises the steps of S1, carrying out blade design, S2, carrying out vibration calculation, S3, carrying out determination of the number of nozzles and position arrangement, S4, carrying out flow calibration, S5, carrying out temperature calibration, S6, carrying out strain gauge adhesion, S7, carrying out vibration strain response measurement, S8, carrying out resonance margin evaluation, stopping when the design requirement is met, and repeating S1 when the design requirement is not met, so that the problems that the test precision, efficiency and safety cannot be ensured, and the resonance risk cannot be accurately evaluated in the existing scheme design method are not solved. In a patent document CN115752977A, a gas turbine rotary blade vibration measurement test bed and a method based on tip timing are disclosed, wherein the test bed comprises a first mounting seat, a sensor supporting seat, a second mounting seat and a motor supporting seat which are fixed on a base, a main shaft is respectively arranged on the first mounting seat and the second mounting seat through bearings at two ends of the sensor supporting seat, the sensor supporting seat above the main shaft is of a downward bending arch structure, a gas-driven nozzle and at least one tip timing sensor are arranged on the sensor supporting seat, the main shaft is in transmission connection with one end of a torque rotating speed sensor through a coupler, and the other end of the torque rotating speed sensor is in transmission connection with a motor arranged on the motor supporting seat, so that the problems that test precision, efficiency and safety cannot be ensured and resonance risks cannot be accurately estimated in the existing scheme design method are not solved. In summary, the above two existing patents do not solve the problem that the existing design method cannot ensure the test precision, efficiency and safety, and is difficult to accurately evaluate the resonance risk. Disclosure of Invention Based on the technical problems, the invention provides a blade dynamic frequency test determining method, a device, electronic equipment and a test system, and solves the problems that test precision, efficiency and safety cannot be ensured and resonance risks cannot be accurately es