Single-sensing double-blade tip timing vibration speed measurement method and system

Abstract

The invention discloses a single-sensing double-blade tip timing vibration speed measurement method, system, medium and equipment, and the method comprises the steps: only installing a blade tip timing sensor in the circumferential direction of a rotor blade case, and obtaining a blade arrival time sequence generated when rotor blades sequentially pass through the blade tip timing sensor; calculating the instantaneous rotating speed of the rotor based on the arrival time intervals of all adjacent rotor blades; the blade tip linear velocity between the two rotor blades is extracted by combining the circumferential included angle and the measuring point radius of any two rotor blades in the blade disc; removing a trend term related to the rotating speed from the blade tip linear velocity to obtain a velocity quantity reflecting the real vibration characteristics of any two rotor blades; a two-degree-of-freedom dynamic model is constructed by combining prior information of a blade Campbell diagram, and double-blade vibration parameter identification is realized by adopting a nonlinear least square fitting method.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of non-contact measurement of rotating machinery rotor blades, and particularly relates to a single-sensor double-blade tip timing vibration velocity measurement method, system, medium and equipment. BACKGROUND

[0002] Blade vibration monitoring is a core problem for safe operation of rotating machinery such as aircraft engines and gas turbines. With the continuous increase in blade size and rotational speed, traditional contact measurement methods are difficult to achieve long-term stable work in complex environments such as high temperature, high speed and strong aerodynamic load. In contrast, the Blade Tip Timing (BTT) technology, based on the principle of non-contact measurement, can achieve online observation of blade vibration without interfering with the normal operation of the equipment, and has become an important research direction in the field of turbomachinery health monitoring in recent years. The basic principle of BTT is to arrange a number of tip timing sensors in the circumferential direction of the casing. When the rotor blades pass through the measurement points in turn, the sensors generate pulse signals and record the time sequence of the blade arrival. By comparing with the arrival time under ideal non-vibration conditions, the circumferential displacement information of the blade can be obtained, and the vibration characteristics of the entire stage blade can be further reconstructed. Since this method can achieve non-contact measurement during high-speed rotation of the rotor, it has been widely used in the field of aircraft engines. However, the existing BTT method still has the following limitations in practical application: first, it relies on shaft key phase sensors or multiple sensor arrangement in the circumferential direction of the casing, which not only significantly increases the hardware cost of the system, but also is limited by the space and structure of the casing, making it difficult to implement on some engine models. Second, the assumption of signal synchronization between multiple sensors and constant speed is often difficult to meet in actual variable speed conditions, which can easily lead to parameter extraction errors; third, in complex operating environments such as strong airflow, temperature fluctuations and electromagnetic interference, some sensors may fail or data may be distorted, further reducing the reliability of the monitoring results. Therefore, how to accurately measure and extract blade vibration characteristics under variable speed conditions while relying only on a single sensor under the condition of limited key phase sensor installation has become a key problem that needs to be solved in the development of BTT technology. If this problem can be solved, it can not only effectively reduce the complexity and cost of engineering application of the system, but also significantly improve the adaptability and robustness of the method in complex conditions.

[0003] The information disclosed in the background section merely to enhance the understanding of the background of the application, therefore can contain information which is not prior art known to those of ordinary skill in the art. SUMMARY

[0004] The application provides a single-sensor double-blade tip timing vibration speed measurement method, system, medium and equipment.

[0005] A single-sensor double-blade tip timing vibration speed measurement method comprises the following steps.

[0006] In a first step (S1), only one tip timing sensor is installed in the circumferential direction of a rotor blade casing, and a blade arrival time sequence generated by the rotor blades passing through the tip timing sensor in turn is obtained.

[0007] In a second step (S2), the rotor instantaneous rotating speed is calculated based on the arrival time interval of all adjacent rotor blades.

[0008] In a third step (S3), the tip line speed between two rotor blades is extracted in combination with the circumferential included angle of the two rotor blades in the blade disc and the measuring point radius.

[0009] In a fourth step (S4), the overall trend item caused by the rotating speed is removed from the tip line speed, so as to extract a speed quantity capable of reflecting the real vibration characteristics of the two rotor blades.

[0010] In a fifth step (S5), the excitation order prior information of the blade resonance interval is extracted in combination with the blade Campbell diagram, a two-degree-of-freedom dynamic model is constructed, and the nonlinear least square fitting method is adopted to realize the double-blade vibration parameter identification.

[0011] In the single-sensor double-blade tip timing vibration speed measurement method, in the first step (S1), the rotor comprises rotor blades, the tip timing sensor continuously collects circle data under the variable rotating speed condition, and an arrival time sequence with a length of is formed, and the time sequence of the rotor blades passing through the tip timing sensor in turn is T = [ t 1 1 ⋯ t N b 1 t 1 2 ⋯ t N b N r ] , wherein is the arrival time of the first blade in the first circle obtained by the sensor.

[0012] In the single-sensor double-blade tip timing vibration speed measurement method, in the second step (S2), the arrival time difference between two adjacent rotor blades is used to estimate the instantaneous rotating speed, and the results calculated by all adjacent rotor blades are averaged to measure the rotating frequency of the first circle, which is , wherein represents the arrival time of the first blade in the first circle obtained by the sensor. ​​​ the difference between the arrival times of the first blade and the second blade. the difference between the arrival times of the first blade and the second blade. the difference between the arrival times of the first blade and the second blade.

[0013] In the single-sensor double-blade tip timing vibration velocity measurement method, in the third step (S3), the formula for calculating the tip line velocity between the two rotor blades is wherein, is the tip line velocity between any two blades, is the circumferential angle difference between the two blades, is the tip point radius, is the arrival time of the first blade, the difference between the arrival times of the first blade and the second blade. the difference between the arrival times of the first blade and the second blade. the difference between the arrival times of the first blade and the second blade.

[0014] In the single-sensor double-blade tip timing vibration velocity measurement method, in the fourth step (S4), the removal of the speed-related trend term is to subtract the speed trend component from the inter-blade tip line velocity signal to obtain a velocity quantity that can reflect the true vibration characteristics of any two rotor blades, wherein, represents the rotational line velocity of the rotor at the first revolution, and is referred to as the inter-blade tip vibration velocity of the first revolution.

[0015] In the single-sensor double-blade tip timing vibration velocity measurement method, in the fifth step (S5), the inter-blade tip vibration velocity single-frequency synchronous vibration response represents a two-degree-of-freedom dynamic model as wherein and represent the loss factor; and are the damping ratios of the two blades, respectively; and are the natural frequencies of the two blades, respectively; is the excitation order corresponding to the blade resonance, which is a positive integer; and are the initial phases of the vibration of the two blades caused by external force, respectively; and are the static amplitudes of the two blades under external force, respectively; and are the angular frequencies of the vibration of the two blades caused by external force, respectively; is the direct current offset of the inter-blade tip vibration velocity.

[0016] ​​In the single-sensor double-blade tip timing vibration velocity measurement method, in the fifth step (S5), the excitation order of the single-frequency vibration of the rotor blade is acquired through prior knowledge in the blade Campbell diagram The Levenberg-Marquardt method is used for nonlinear least square fitting of the two resonance peaks in combination with the single-frequency synchronous vibration response of the inter-blade tip vibration velocity, so as to obtain vibration parameters corresponding to the two resonance peaks of the rotor blade, including the blade natural frequency, the damping ratio, the initial phase and the amplitude.

[0017] A system for implementing the method comprises:

[0018] A blade arrival time measurement module is configured to collect, in real time, a blade arrival time sequence recorded by a single tip timing sensor installed on the circumference of the casing;

[0019] A rotor instantaneous rotating speed calculation module is configured to calculate the instantaneous rotating speed based on the interval of adjacent blade arrival times, and to average the calculation results of all adjacent blades in the same rotating order to obtain a stable rotating speed estimation;

[0020] A tip inter-blade vibration velocity calculation module is configured to calculate the corresponding tip linear velocity in combination with the circumferential angle of any two blades in the blade disc and the radius of the tip measurement point, and to obtain the inter-blade tip vibration velocity capable of reflecting the real vibration characteristics of the blade by removing the rotating speed related trend item;

[0021] A double-blade vibration parameter identification module is configured to, after obtaining the inter-blade tip vibration velocity, establish a double-degree-of-freedom dynamic model, and to use the nonlinear least square fitting method to fit the vibration response of the target order, so as to identify the natural frequency, the damping ratio, the initial phase and the amplitude of the blade.

[0022] A computer storage medium, the storage medium comprising computer instructions, when running on a computer, causing the computer to execute the method.

[0023] An electronic device, the electronic device comprising:

[0024] A memory, a processor and a computer program stored on the memory and executable on the processor, wherein,

[0025] The processor implements the method when executing the program.

[0026] Compared with the prior art, the present application has the following advantages: the present application calculates the inter-blade tip vibration velocity signal by a single sensor, which naturally integrates the vibration information of two blades, avoids the complex arrangement of relying on the key phase reference or multi-sensor synchronous measurement in the traditional method, and effectively reduces the hardware cost and structural complexity of the monitoring system; at the same time, since the inter-blade tip vibration velocity is directly processed instead of single-blade vibration displacement, the common mode components of the double blades are offset to each other, effectively suppressing the interference caused by the speed estimation error and the trend term under the variable speed condition, so that the synchronous vibration parameters can be more accurately and stably identified; in addition, the inter-blade tip vibration velocity measurement and parameter identification method proposed by the present application can maintain good adaptability and robustness under a wide speed range and fast variable speed environment, further improving the observability and calculation accuracy of the synchronous vibration characteristics, and has the advantages of simple implementation and high engineering application value. BRIEF DESCRIPTION OF DRAWINGS

[0027] Various other advantages and benefits of the present application will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The accompanying drawings are included to provide a better understanding of the preferred embodiments and are not to be considered limitations of the present application. It should be readily understood that the drawings described below are only some embodiments of the present application, and other drawings can be obtained from these drawings without creative labor for those of ordinary skill in the art. Moreover, the same reference numerals are used to represent the same components throughout the drawings.

[0028] In the drawings:

[0029] Figure 1 A flowchart of a single-sensor inter-blade tip timing measurement method provided for an embodiment of the present application is shown in the figure;

[0030] Figure 2 A structural schematic diagram of a single-sensor inter-blade tip timing measurement system provided for an embodiment of the present application is shown in the figure;

[0031] Figure 3 A schematic diagram of a single-sensor inter-blade tip vibration velocity measurement principle provided for an embodiment of the present application is shown in the figure;

[0032] Figure 4 A single-sensor measurement result of the inter-blade tip vibration velocity of the simulated rotor provided for an embodiment of the present application is shown in the figure;

[0033] Figure 5 A Campbell diagram of a five-blade simulated rotor provided for an embodiment of the present application is shown in the figure;

[0034] Fig. 6(a) to Fig. 6(b) are schematic diagrams of parameter identification results of two resonance regions by using single-sensor inter-blade tip timing vibration velocity measurement according to an embodiment of the present application, wherein Fig. 6(a) is a schematic diagram of the results of vibration data in the 119s-132s resonance region, and Fig. 6(b) is a schematic diagram of the results of vibration data in the 187s-208s resonance region. Figure 4 Fig. 6(a) to Fig. 6(b) are schematic diagrams of parameter identification results of two resonance regions by using single-sensor inter-blade tip timing vibration velocity measurement according to an embodiment of the present application, wherein Fig. 6(a) is a schematic diagram of the results of vibration data in the 119s-132s resonance region, and Fig. 6(b) is a schematic diagram of the results of vibration data in the 187s-208s resonance region. Figure 4 Fig. 6(a) to Fig. 6(b) are schematic diagrams of parameter identification results of two resonance regions by using single-sensor inter-blade tip timing vibration velocity measurement according to an embodiment of the present application, wherein Fig. 6(a) is a schematic diagram of the results of vibration data in the 119s-132s resonance region, and Fig. 6(b) is a schematic diagram of the results of vibration data in the 187s-208s resonance region.

[0035] The present application will be further explained with reference to the accompanying drawings and embodiments. DETAILED DESCRIPTION

[0036] The specific embodiments of the present application will be described below in detail with reference to the accompanying drawings. Although specific embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided so that the present application can be more thoroughly understood and the scope of the present application can be accurately conveyed to those skilled in the art.

[0037] It should be noted that some terms are used in the specification and claims to refer to specific components. Those skilled in the art should understand that the same component can be referred to by different terms. The specification and claims of the present application do not distinguish components based on differences in terms, but rather on differences in functionality. As mentioned throughout the specification and claims, "comprising" or "including" is an open term, which should be interpreted as "including but not limited to". The subsequent description of the specification is a preferred embodiment for implementing the present application, and is intended to serve the purpose of the general principles of the specification, and not to limit the scope of the present application. The scope of protection of the present application is defined by the appended claims.

[0038] For the convenience of understanding the embodiments of the present application, the following will be further explained and described with specific examples by combining the drawings, and each drawing does not constitute a limitation to the embodiments of the present application.

[0039] As Figure 1 As shown in Fig. 6(b), the single-sensor double-blade tip timing vibration velocity measurement method includes the following steps:

[0040] The first step S1 is to install only one tip timing sensor in the circumferential direction of the rotor blade casing, and to obtain the blade arrival time sequence generated by the rotor blades passing through the tip timing sensor in turn;

[0041] The second step S2 is to calculate the rotor instantaneous speed based on the arrival time interval of all adjacent rotor blades;

[0042] The third step, S3, involves combining the circumferential angle between any two rotor blades in the bladed disk with the radius of the measuring point to extract the tip linear velocity between the two rotor blades.

[0043] In the fourth step S4, the overall trend term caused by the rotational speed is removed from the blade tip linear velocity, thereby extracting the velocity quantity that can reflect the true vibration characteristics of any two rotor blades.

[0044] In the fifth step S5, the prior information of the excitation order in the resonance interval of the blade is extracted by combining the Campbell diagram of the blade, a two-degree-of-freedom dynamic model is constructed, and the vibration parameters of the two blades are identified by nonlinear least squares fitting method.

[0045] In a preferred embodiment of the single-sensor dual-blade tip timing vibration velocity measurement method, in the first step S1, the rotor includes... Each rotor blade, with a timing sensor at the blade tip continuously collecting data under variable speed conditions. Circle data, constituting length The arrival time sequence, the time sequence of the rotor blades passing through the tip timing sensor in sequence is as follows: T = [ t 1 1 ⋯ t N b 1 t 1 2 ⋯ t N b N r ] ,in The first sensor to acquire The first leaf in the The arrival time of the circle.

[0046] In a preferred embodiment of the single-sensor dual-blade tip timing vibration velocity measurement method, in the second step S2, the instantaneous rotational speed is estimated using the arrival time difference between two adjacent rotor blades, and the average measurement is performed using the results calculated from all adjacent rotor blades. The rotation frequency of the circle is ,in Indicates the sensor at the first The first record of the transfer The first blade and the first The difference in arrival time of each blade.

[0047] In a preferred embodiment of the single-sensor dual-blade tip timing vibration velocity measurement method, in the third step S3, the formula for calculating the tip linear velocity between the two rotor blades is as follows: ,in, Let be the tip linear velocity between any two blades. The difference in circumferential angle between the two blades. The radius of the measuring point at the leaf tip is... For the sensor in the first The first record of the transfer The first blade and the first The difference in arrival time of each blade.

[0048] In the preferred embodiment of the single-sensor dual-blade tip-timing vibration velocity measurement method, in the fourth step S4, the removal of the rotational speed related trend term is to subtract the rotational speed trend component from the inter-blade tip speed signal to obtain a velocity quantity that can reflect the true vibration characteristics of any two rotor blades, wherein, represents the rotational linear speed of the rotor, represents the inter-blade tip vibration speed of the rotor, represents the inter-blade tip vibration speed of the rotor, represents the inter-blade tip vibration speed of the rotor.

[0049] In the preferred embodiment of the single-sensor dual-blade tip-timing vibration velocity measurement method, in the fifth step S5, the inter-blade tip vibration speed single-frequency synchronous vibration response two-degree-of-freedom dynamic model is represented as wherein, and represent the loss factor; and are the damping ratios of the two blades, respectively; and are the natural frequencies of the two blades, respectively; is the excitation order corresponding to the blade resonance, which is a positive integer; and are the initial phases of the vibration of the two blades caused by external force, respectively; and are the static amplitudes of the two blades under external force, respectively; and are the angular frequencies of the vibration of the two blades caused by external force, respectively; is the direct current offset of the inter-blade tip vibration speed.

[0050] In the preferred embodiment of the single-sensor dual-blade tip-timing vibration velocity measurement method, in the fifth step S5, the excitation order of the single-frequency vibration of the rotor blade is obtained by prior knowledge in the blade Campbell diagram and the Levenberg-Marquardt method is used to perform nonlinear least squares fitting on the two resonance peaks in combination with the inter-blade tip vibration speed single-frequency synchronous vibration response, thereby obtaining vibration parameters corresponding to the two rotor blade resonance peaks, including blade natural frequency, damping ratio, initial phase and amplitude.

[0051] A system for implementing the method comprises:

[0052] a blade arrival time measurement module for real-time acquisition of a blade arrival time sequence recorded by a single tip-timing sensor installed on the circumference of the casing;

[0053] a rotor instantaneous rotating speed calculation module for calculating the instantaneous rotating speed based on the time interval of adjacent blades and averaging the calculation results of all adjacent blades in the same rotating cycle to obtain a stable rotating speed estimation;

[0054] a blade tip interblade vibration speed calculation module for calculating the corresponding blade tip linear speed by combining the circumferential angle of any two blades in the blade disc and the radius of the blade tip measurement point and removing the rotating speed related trend item to obtain the interblade blade tip vibration speed reflecting the real vibration characteristics of the blades;

[0055] a double-blade vibration parameter identification module for establishing a double-degree-of-freedom dynamic model after obtaining the interblade blade tip vibration speed and fitting the vibration response of the target order by using a nonlinear least square fitting method to identify the natural frequency, damping ratio, initial phase and amplitude of the blades.

[0056] A computer storage medium, the storage medium comprising computer instructions, when running on a computer, cause the computer to execute the method.

[0057] An electronic device, the electronic device comprising:

[0058] a memory, a processor and a computer program stored on the memory and executable on the processor, wherein,

[0059] the processor implements the method when executing the program.

[0060] In one embodiment, a single-sensor double-blade blade tip timing vibration speed measurement method comprises,

[0061] In a first step S1, only one blade tip timing sensor is installed in the circumferential direction of the rotor blade casing, and a blade arrival time sequence generated by the rotor blades passing the sensor in turn is obtained;

[0062] In a second step S2, the rotor instantaneous rotating speed is calculated based on the time interval of all adjacent blades;

[0063] In a third step S3, the blade tip linear speed between two blades is extracted by combining the circumferential angle of any two blades in the blade disc and the radius of the measurement point;

[0064] In a fourth step S4, the overall trend item caused by the rotating speed is deducted from the blade tip linear speed to obtain a speed quantity reflecting the real vibration characteristics of any two blades.

[0065] In a fifth step S5, a double-degree-of-freedom dynamic model is constructed by combining the blade Campbell diagram priori information, and a nonlinear least square fitting method is used to realize double-blade vibration parameter identification.

[0066] To further understand the present invention, specific embodiments are described below. It should be emphasized that the following descriptions are merely exemplary and should not be construed as limiting the present invention.

[0067] 1. In the vibration test of a five-bladed simulated rotor, the rotor speed gradually increased from 3000 r / min to 15000 r / min over 500 seconds, and then decreased to approximately 5000 r / min. First, the arrival time sequence of the entire blade revolution was obtained using a single blade tip timing sensor. Then, the arrival time series of any two blades are selected and calculated in conjunction with their included angle on the rotor circumference to obtain the inter-blade tip vibration velocity that simultaneously contains the vibration information of both blades. ,like Figure 4 As shown.

[0068] 2. Based on the calculated inter-leaf tip vibration velocity It can intuitively identify the resonance interval, based on Figure 4 As a result, obvious resonance characteristics were observed in the two intervals of 119s-132s and 187s-208s. Data from these two intervals were extracted and plotted as a frequency-inter-tip vibration velocity diagram (see...). Figure 4 ).

[0069] 3. Combine the five-bladed simulated rotor Campbell diagram (see...) Figure 5 By combining the measured inter-blade and blade tip vibration velocity data, prior information about the first-order modal resonance of the blade can be obtained, namely, the excitation orders corresponding to the two resonance intervals of 119s–132s and 187s–208s are 4 and 3, respectively.

[0070] 4. Based on the frequency-inter-blade tip vibration velocity diagram, and combined with the inter-blade tip vibration velocity response equation described in claim 7, the Levenberg-Marquardt algorithm is used to perform nonlinear least-squares fitting on the two resonance intervals respectively (see Figures 6(a) to 6(b)), thereby extracting the vibration parameters of the two blades, including natural frequency, damping ratio, initial phase, and amplitude. Further explanation is needed regarding the blade displacement amplitude. and velocity amplitude The relationship can be represented as ,in The modal frequencies of the two blades are 617.36 Hz and 624.78 Hz, respectively, the velocity amplitudes are 0.24 m / s and 0.50 m / s, respectively, and the corresponding displacement amplitudes are 0.06 mm and 0.13 mm, respectively, in the resonance interval of 119 s-132 s; the modal frequencies of the two blades are 648.63 Hz and 660.20 Hz, respectively, the velocity amplitudes are 0.94 m / s and 1.14 m / s, respectively, and the corresponding displacement amplitudes are 0.23 mm and 0.27 mm, respectively, in the resonance interval of 187 s-208 s.

[0071] Further, the application only arranges one blade tip timing sensor in the circumferential direction of the rotor case, collects the arrival times of all blades passing through, and forms a time sequence. This reduces system complexity and cost, avoids the dependence on multiple sensor arrays or key phase sensors in traditional BTT technology, significantly reduces the number of hardware and installation space requirements, is easier to implement in engines with limited space or complex structure (such as small aviation engines), and enhances the deployability of the technology. The time synchronization error problem between multiple sensors is eliminated, and the system robustness is improved. The arrival time interval between all adjacent blades in the same rotation is used to calculate the local rotation frequency, and the average value is taken as the stable instantaneous rotation speed estimation of the rotation. Realize the rotation speed tracking without key phase signal: without additional installation of key phase sensor, high precision instantaneous rotation speed can be obtained, which is suitable for occasions where key phase device cannot be installed. By averaging the time difference of multiple adjacent blade pairs, the influence of single measurement noise or abnormal data on rotation speed estimation is effectively suppressed. Provide accurate time-varying rotation speed reference for subsequent vibration analysis, which is the basis for realizing vibration parameter identification under variable rotation speed. Build "inter-blade" dynamic information channel: convert the traditional single blade displacement observation into the relative motion speed between two blades, and naturally integrate the vibration states of the two blades. The blade tip linear velocity directly reflects the dynamic behavior of the blade during rotation, and has more dynamic characterization ability than the simple time offset. The method has universality and can be used for key monitoring of specific blade combinations, and is suitable for local damage or heterogeneous blade analysis. Subtract the trend component caused by rotation speed change from the blade tip linear velocity to obtain "inter-blade blade tip vibration velocity" reflecting only the vibration characteristics, effectively separate the additional acceleration component caused by true vibration, and avoid the pseudo vibration signal caused by acceleration and deceleration during variable rotation speed. Extract the pure vibration response signal, so that the characteristics such as resonance peak are more clear and identifiable in time domain or rotation speed-amplitude diagram. Since the two blades share the same rotation speed background, the detrending process can offset the common mode error and enhance the measurement robustness. Based on the prior knowledge of Campbell diagram, determine the excitation order, establish the coupled vibration response model of double blades, and use Levenberg-Marquardt (LM) algorithm for nonlinear least squares fitting of inter-blade blade tip vibration velocity, to inverse the natural frequency, damping ratio, initial phase and amplitude of each blade. Although only a single sensor is used, the vibration characteristics of two blades can still be distinguished, breaking through the limitation of traditional single sensor that can only monitor a single blade and the insufficient identification accuracy under fast variable working conditions. Combined with the resonance order information provided by the Campbell diagram, the degrees of freedom of the fitting model are constrained to avoid multiple solutions and convergence failure. The two-degree-of-freedom model is more close to the possible aerodynamic or structural coupling effect between actual blades, and improves the authenticity of parameter identification. Suitable for wide speed range and fast variable working condition: LM algorithm has strong adaptability to nonlinear systems, and can stably extract vibration parameters under complex operating conditions.

[0072] Although the embodiments of the present application have been described above with reference to the accompanying drawings, the present application is not limited to the above-described specific embodiments and areas of application, and the above-described specific embodiments are merely illustrative and instructive, but are not restrictive. Many modifications can be made by those skilled in the art under the teachings of the present specification and without departing from the scope of the present application as defined by the claims.

Claims

1. A method for measuring the timed vibration velocity of a single-sensor dual-blade tip, characterized in that, Includes the following steps: In the first step (S1), only one blade tip timing sensor is installed in the circumferential direction of the rotor blade casing to obtain the blade arrival time sequence generated by the rotor blades passing through the blade tip timing sensor in sequence. The second step (S2) is to calculate the instantaneous rotor speed based on the arrival time interval of all adjacent rotor blades; The third step (S3) involves combining the circumferential angle between any two rotor blades in the bladed disk and the radius of the measuring point to extract the tip linear velocity between the two rotor blades. The fourth step (S4) is to remove the overall trend term caused by the rotational speed from the blade tip linear velocity, thereby extracting the velocity quantity that can reflect the true vibration characteristics of any two rotor blades. In the fifth step (S5), the prior information of the excitation order of the blade resonance interval is extracted by combining the blade Campbell diagram, a two-degree-of-freedom dynamic model is constructed, and the vibration parameters of the two blades are identified by nonlinear least squares fitting method.

2. The method for measuring the timed vibration velocity at the tip of a single-sensor dual-blade blade according to claim 1, characterized in that, Preferably, in the first step (S1), the rotor includes Each rotor blade, with a timing sensor at the blade tip continuously collecting data under variable speed conditions. Circle data, constituting length The arrival time sequence, the time sequence of the rotor blades passing through the tip timing sensor in sequence is as follows: ,in The first sensor to acquire The first leaf in the The arrival time of the circle.

3. The method for measuring the timed vibration velocity at the tip of a single-sensor dual-blade blade according to claim 2, characterized in that, In the second step (S2), the instantaneous rotational speed is estimated using the arrival time difference between two adjacent rotor blades, and the result calculated from all adjacent rotor blades is averaged for measurement. The rotation frequency of the circle is ,in Indicates the sensor at the first The first record of the transfer The first blade and the first The difference in arrival time of each blade.

4. The method for measuring the timed vibration velocity at the tip of a single-sensor dual-blade blade according to claim 3, characterized in that, In the third step (S3), the formula for calculating the tip linear velocity between the two rotor blades is as follows: ,in, Let be the tip linear velocity between any two blades. The difference in circumferential angle between the two blades. The radius of the measuring point at the leaf tip is... For the sensor in the first The first record of the transfer The first blade and the first The difference in arrival time of each blade.

5. The method for measuring the timed vibration velocity at the tip of a single-sensor dual-blade blade according to claim 4, characterized in that, In the fourth step (S4), removing the speed-related trend term involves subtracting the speed-related trend component from the inter-blade tip linear velocity signal to obtain a velocity quantity that can reflect the true vibration characteristics of any two rotor blades. ,in, Indicates the first of the rotors The linear velocity of rotation, and Called the first The vibration speed between the blade tips and the rotating blades.

6. The method for measuring the timed vibration velocity at the tip of a single-sensor dual-blade blade according to claim 5, characterized in that, In step five (S5), the single-frequency synchronous vibration response two-degree-of-freedom dynamic model of the inter-blade tip vibration velocity is expressed as follows: ,in and Represents the loss factor; and These are the damping ratios of the two blades, respectively. and These are the natural frequencies of the two blades, respectively. The excitation order corresponding to blade resonance is a positive integer; and These represent the initial phases of the vibrations caused by external forces on the two blades. and These are the static amplitudes of the two blades under external force, respectively; and These are the angular frequencies of vibration caused by external forces on the two blades, respectively. This represents the DC offset of the vibration velocity between the blade tips and inter-blade surfaces.

7. The method for measuring the timed vibration velocity at the tip of a single-sensor dual-blade blade according to claim 6, characterized in that, In the fifth step (S5), the excitation order of the rotor blade's single-frequency vibration is obtained using prior knowledge from the blade's Campbell diagram. Furthermore, by combining the single-frequency synchronous vibration response of the blade tip vibration velocity, the Levenberg-Marquardt method was used to perform nonlinear least-squares fitting on the two resonance peaks, thereby obtaining the vibration parameters corresponding to the resonance peaks of the two rotor blades, including the blade natural frequency, damping ratio, initial phase, and amplitude.

8. A system for implementing the method according to any one of claims 1-7, characterized in that, It includes: The blade arrival time measurement module is used to acquire in real time the blade arrival time sequence recorded by a single blade tip timing sensor installed on the circumference of the casing; The rotor instantaneous speed calculation module is used to calculate the instantaneous speed based on the arrival time interval of adjacent blades, and to average the calculation results of all adjacent blades in the same revolution to obtain a stable speed estimate. The blade tip and inter-blade vibration velocity calculation module is used to calculate the corresponding blade tip linear velocity by combining the circumferential angle between any two blades in the blade disk and the radius of the blade tip measuring point, and obtain the inter-blade and blade tip vibration velocity that can reflect the true vibration characteristics of the blade by removing the rotational speed related trend term. The dual-blade vibration parameter identification module is used to establish a two-degree-of-freedom dynamic model after obtaining the vibration velocity between the blade tip and between the blades, and to fit the vibration response of the target order using a nonlinear least squares fitting method to identify the natural frequency, damping ratio, initial phase and amplitude of the blade.

9. A computer storage medium, characterized in that, The storage medium includes computer instructions that, when executed on a computer, cause the computer to perform the method as described in any one of claims 1-7.

10. An electronic device, characterized in that, The electronic device includes: Memory, processor, and computer programs stored in memory and executable on the processor, wherein, When the processor executes the program, it implements the method as described in any one of claims 1-7.

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