An analysis method and system of unsteady aerodynamic force considering blade mistuning

Abstract

The application relates to the technical field of aero-engines and discloses an analysis method and system of unsteady aerodynamic force considering blade mistuning, wherein a multi-channel grid model containing two adjacent rotor blades and flow channels between the two rotor blades is constructed, an influence coefficient method is used to obtain dangerous modes and dangerous diameters of the rotor blades; under the condition of considering mistuning amounts of the rotor blades, an unsteady flow field of the rotor blades under the dangerous modes and the dangerous diameters is calculated based on a dynamic grid mapping method, a proxy model between unsteady aerodynamic force of the blades and vibration displacement is constructed based on a dynamic mode decomposition method, and unsteady aerodynamic force and vibration displacement information of the rotor blades are obtained by carrying out structural dynamics simulation analysis of the rotor blades, so that the unsteady aerodynamic force change of the blades caused by frequency mistuning of the compressor rotor blades can be accurately simulated, and accurate unsteady aerodynamic force is provided for multi-physical field solving of the rotor blades.

Description

Technical Field

[0001] This invention relates to the field of aero-engine technology, and discloses an analysis method and system for unsteady aerodynamic forces considering blade detuning. Background Technology

[0002] The high thrust-to-weight ratio design of aero-engines places increasingly stringent demands on the single-stage aerodynamic load of the compression system, leading to a continuous increase in the temperature load and unsteady aerodynamic forces experienced by the compressor blades. To further reduce weight, engines are employing a large amount of lightweight new materials in their manufacturing process, resulting in more complex three-dimensional bending and twisting characteristics in the blade profiles. These design trends all contribute to an increase in the unsteady aerodynamic forces generated by unstable flow within the compressor, causing the airflow excitation frequency to exhibit broadband multimodal characteristics. This results in higher dynamic stress levels on the rotor blades, often inducing high-cycle fatigue problems in aero-engine compressor blades.

[0003] The flow-induced vibration problem of compressor blades is essentially a typical multi-physics coupling problem involving fluid, solid, and thermal fields. During the design phase, the assessment of unsteady aerodynamic forces on compressor rotor blades directly impacts blade reliability. Compressor blades are typically machined using five-axis CNC machine tools, requiring extremely high profile precision. Due to inherent limitations in machining, each blade profile exhibits a certain deviation, meaning circumferential frequency detuning. This detuning manifests in blade vibration as increased amplitude in some blades, with vibration frequencies distributed within a specific region. For example, machining a solid bladed disk using a five-axis CNC machine tool typically introduces approximately 5% frequency detuning. Because of circumferential inhomogeneity, traditional unsteady numerical simulation methods must employ a full-circumference approach to calculate unsteady aerodynamic forces, resulting in extremely large computational loads and simulation times that are difficult to meet engineering application requirements. Summary of the Invention

[0004] The purpose of this invention is to provide an analysis method and system for unsteady aerodynamic forces considering blade detuning, which can accurately simulate the changes in unsteady aerodynamic forces of compressor rotor blades caused by frequency detuning, and provide accurate unsteady aerodynamic forces for solving multiphysics problems of rotor blades.

[0005] To achieve the above-mentioned technical effects, the technical solution adopted by the present invention is as follows:

[0006] An analytical method for unsteady aerodynamic forces considering blade mistuning includes:

[0007] Using the flow channel between two adjacent rotor blades of the compression component as a single channel, a multi-channel mesh model is constructed by selecting multiple continuously distributed single channels on the entire rotor ring of the compression component.

[0008] Steady-state calculations of the multi-channel mesh model were performed using CFD software to obtain the steady flow field and the surface pressure and surface temperature of each rotor blade under the multi-channel mesh model.

[0009] Using the surface pressure, surface temperature, and rotor speed of the corresponding rotor blades as the prestress input for modal analysis, the natural frequencies and modal vectors of the rotor blades under the test mode shape are obtained through simulation.

[0010] Unsteady computational boundary conditions are applied to the multi-channel mesh model, and the rotor blades in the middle of the multi-channel mesh model are set as dynamic mesh domains, while the remaining rotor blades are set as rigid states. Based on the natural frequencies and modal vectors under the test mode shape, the modal work of each node diameter of the rotor blades under the test mode shape is obtained by analyzing the influence coefficient method based on time progression.

[0011] The pitch diameter with the minimum modal work of the rotor blade under the test mode shape is defined as the critical pitch diameter. The rotor blade in the middle of the multi-channel mesh model is set as the moving mesh domain, and the other rotor blades are set as rigid. Multi-channel unsteady calculation is carried out under the critical pitch diameter considering the preset detuning conditions of the rotor blade. The pressure, displacement, velocity and blade surface normal vector of each mesh point on the rotor blade surface are output at each time step.

[0012] Based on the pressure, displacement, velocity, and blade surface normal vector of each grid point on the rotor blade surface at each time step, a proxy model between the unsteady aerodynamic forces and vibration displacements of the blade under the critical nodal diameter is established using the dynamic mode decomposition method. The rotor blade structure dynamics simulation analysis is carried out using the fluid-structure interaction method to obtain the unsteady aerodynamic forces and vibration displacement information of the blade at different times.

[0013] Furthermore, at least 7 continuously distributed single channels are selected to construct a multi-channel mesh model, and the number of continuously distributed single channels is odd.

[0014] Furthermore, utilizing Analysis yields modal work of the rotor blades at each pitch diameter under the tested vibration mode. ,in This refers to the number of single channels in a multi-channel mesh model. , To assess the vibration period of the rotor blades under different vibration modes, To assess the vibration frequency of the rotor blades under the specified mode shape, To assess the phase angle of the rotor blades under the vibration mode, For numerical simulation time, , This represents the integration over the closed surface of the modal forces of the rotor blades. The pressure on the blade surface. To evaluate the modal vectors of the rotor blades under different vibration modes, The normal vector of the rotor blade surface. The surface area of ​​the rotor blades. This is the differential symbol.

[0015] Furthermore, the preset detuning condition is: the maximum detuning amount of the blade frequency is The sweep frequency of rotor blade vibration is set to , ,in To assess the natural frequencies under different vibration modes, This represents the numerical simulation time.

[0016] To achieve the above-mentioned technical effects, the present invention also provides an analysis system considering unsteady aerodynamic forces caused by blade mistuning, comprising:

[0017] The network model building module is used to construct a multi-channel mesh model by selecting multiple continuously distributed single channels on the entire rotor ring of the compression component, taking two adjacent rotor blades of the compression component and the flow channel between them as single channels.

[0018] The first analysis module is used to perform steady-state calculations on the multi-channel mesh model using CFD software, and to obtain the steady flow field and the surface pressure P and surface temperature T of each rotor blade under the multi-channel mesh model.

[0019] The second analysis module is used to simulate and obtain the natural frequencies and modal vectors of the rotor blades under the test mode shape by taking the surface pressure, surface temperature and rotor speed of the corresponding rotor blades as the prestress input for modal analysis.

[0020] The third analysis module is used to apply unsteady computational boundary conditions to the multi-channel mesh model, and set the rotor blades in the middle of the multi-channel mesh model as the moving mesh domain, and set the remaining rotor blades as the rigid state. Based on the natural frequency and modal vector under the test mode, the modal work of each node diameter of the rotor blade under the test mode is obtained by using the influence coefficient method based on time progression.

[0021] The fourth analysis module defines the critical pitch diameter as the pitch diameter with the minimum modal work of the rotor blade under the test mode shape. The rotor blade in the middle of the multi-channel mesh model is set as a moving mesh domain, and the other rotor blades are set as rigid. Multi-channel unsteady calculations are carried out under the critical pitch diameter considering the preset detuning conditions of the rotor blade. The module outputs the pressure, displacement, velocity of the mesh points on the rotor blade surface and the blade surface normal vector corresponding to each mesh point at each time step.

[0022] The fifth analysis module is used to establish a proxy model between the unsteady aerodynamic forces and vibration displacements of the blade under the critical nodal diameter based on the pressure, displacement, velocity of the grid points on the rotor blade surface at each time step, as well as the blade surface normal vector corresponding to each grid point. It then uses the fluid-structure interaction method to carry out the dynamic simulation analysis of the rotor blade structure and obtain the unsteady aerodynamic forces and vibration displacement information of the blade at different times.

[0023] Furthermore, in the network model construction module, at least 7 continuously distributed single channels are selected to construct a multi-channel mesh model, and the number of continuously distributed single channels is odd.

[0024] Furthermore, in the third analysis module, using Analysis yields modal work of the rotor blades at each pitch diameter under the tested vibration mode. ,in This refers to the number of single channels in a multi-channel mesh model. , To assess the vibration period of the rotor blades under different vibration modes, To assess the vibration frequency of the rotor blades under the specified mode shape, To assess the phase angle of the rotor blades under the vibration mode, For numerical simulation time, , This represents the integration over the closed surface of the modal forces of the rotor blades. The pressure on the blade surface. To evaluate the modal vectors of the rotor blades under different vibration modes, The normal vector of the rotor blade surface. The surface area of ​​the rotor blades. This is the differential symbol.

[0025] Furthermore, in the fourth analysis module, the preset detuning condition is: the maximum detuning amount of the blade frequency is... The sweep frequency of rotor blade vibration is set to , ,in To assess the natural frequencies under different vibration modes, This represents the numerical simulation time.

[0026] Compared with the prior art, the beneficial effects of the present invention are: the present invention comprehensively considers the influence of blade aerodynamic changes caused by blade detuning on the rotor blade structural dynamics, thereby accurately simulating the unsteady aerodynamic changes of compressor rotor blades caused by frequency detuning, improving the accuracy of numerical simulation, meeting the needs of practical engineering applications, and providing accurate unsteady aerodynamic forces for multi-physics field solutions of rotor blades. Attached Figure Description

[0027] Figure 1 This is a flowchart of the analysis method for considering unsteady aerodynamic forces due to blade detuning in the embodiments. Detailed Implementation

[0028] The present invention will now be described in further detail with reference to the embodiments and accompanying drawings. However, this should not be construed as limiting the scope of the above-described subject matter of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0029] Example 1

[0030] See Figure 1 An analytical method for considering unsteady aerodynamic forces due to blade mistuning includes:

[0031] Using the flow channel between two adjacent rotor blades of the compression component as a single channel, a multi-channel mesh model is constructed by selecting multiple continuously distributed single channels on the entire rotor ring of the compression component.

[0032] The steady-state calculation of the multi-channel mesh model was carried out using CFD software to obtain the steady flow field and the surface pressure P and surface temperature T of each rotor blade under the multi-channel mesh model.

[0033] Using the surface pressure, surface temperature, and rotor speed of the corresponding rotor blades as the prestress input for modal analysis, the natural frequencies and modal vectors of the rotor blades under the test mode shape are obtained through simulation.

[0034] Unsteady computational boundary conditions are applied to the multi-channel mesh model, and the rotor blades in the middle of the multi-channel mesh model are set as dynamic mesh domains, while the remaining rotor blades are set as rigid states. Based on the natural frequencies and modal vectors under the test mode shape, the modal work of each node diameter of the rotor blades under the test mode shape is obtained by analyzing the influence coefficient method based on time progression.

[0035] The pitch diameter with the minimum modal work of the rotor blade under the test mode shape is defined as the critical pitch diameter. The rotor blade in the middle of the multi-channel mesh model is set as the moving mesh domain, and the other rotor blades are set as rigid. Multi-channel unsteady calculation is carried out under the critical pitch diameter considering the preset detuning conditions of the rotor blade. The pressure, displacement, velocity and blade surface normal vector of each mesh point on the rotor blade surface are output at each time step.

[0036] Based on the pressure, displacement, velocity, and blade surface normal vector of each grid point on the rotor blade surface at each time step, a proxy model between the unsteady aerodynamic forces and vibration displacements of the blade under the critical nodal diameter is established using the dynamic mode decomposition method. The rotor blade structure dynamics simulation analysis is carried out using the fluid-structure interaction method to obtain the unsteady aerodynamic forces and vibration displacement information of the blade at different times.

[0037] In this embodiment, a multi-channel mesh model containing two adjacent rotor blades and the flow channel between them is constructed. Steady-state calculations are performed using CFD software to obtain the pressure and temperature distribution on the blade surface, providing accurate prestress input for subsequent modal analysis. The critical modes and critical node diameters of the rotor blades are obtained using the influence coefficient method. Considering the detuning of the rotor blades, the unsteady flow field of the rotor blades under the critical mode and critical node diameter is calculated based on the dynamic mesh mapping method. A proxy model between the unsteady aerodynamic forces and vibration displacements of the blades is constructed based on the dynamic modal decomposition method. Structural dynamics simulation analysis of the rotor blades is conducted to obtain information on the unsteady aerodynamic forces and vibration displacements of the rotor blades. The unsteady aerodynamic force calculation method considering blade detuning proposed in this invention takes into account the influence of blade aerodynamic force changes caused by blade detuning on the structural dynamics of the rotor blades. This allows for accurate simulation of the unsteady aerodynamic force changes of the compressor rotor blades due to frequency detuning, improving the accuracy of numerical simulation and meeting practical engineering applications. It provides accurate unsteady aerodynamic forces for multi-physics field solutions of rotor blades.

[0038] Based on the same inventive concept, this embodiment also provides an analysis system considering unsteady aerodynamic forces caused by blade mistuning, including:

[0039] The network model building module is used to construct a multi-channel mesh model by selecting multiple continuously distributed single channels on the entire rotor ring of the compression component, taking two adjacent rotor blades of the compression component and the flow channel between them as single channels.

[0040] The first analysis module is used to perform steady-state calculations on the multi-channel mesh model using CFD software, and to obtain the steady flow field and the surface pressure P and surface temperature T of each rotor blade under the multi-channel mesh model.

[0041] The second analysis module is used to simulate and obtain the natural frequencies and modal vectors of the rotor blades under the test mode shape by taking the surface pressure, surface temperature and rotor speed of the corresponding rotor blades as the prestress input for modal analysis.

[0042] The third analysis module is used to apply unsteady computational boundary conditions to the multi-channel mesh model, and set the rotor blades in the middle of the multi-channel mesh model as the moving mesh domain, and set the remaining rotor blades as the rigid state. Based on the natural frequency and modal vector under the test mode, the modal work of each node diameter of the rotor blade under the test mode is obtained by using the influence coefficient method based on time progression.

[0043] The fourth analysis module defines the critical pitch diameter as the pitch diameter with the minimum modal work of the rotor blade under the test mode shape. The rotor blade in the middle of the multi-channel mesh model is set as a moving mesh domain, and the other rotor blades are set as rigid. Multi-channel unsteady calculations are carried out under the critical pitch diameter considering the preset detuning conditions of the rotor blade. The module outputs the pressure, displacement, velocity of the mesh points on the rotor blade surface and the blade surface normal vector corresponding to each mesh point at each time step.

[0044] The fifth analysis module is used to establish a proxy model between the unsteady aerodynamic forces and vibration displacements of the blade under the critical nodal diameter based on the pressure, displacement, velocity of the grid points on the rotor blade surface at each time step, as well as the blade surface normal vector corresponding to each grid point. It then uses the fluid-structure interaction method to carry out the dynamic simulation analysis of the rotor blade structure and obtain the unsteady aerodynamic forces and vibration displacement information of the blade at different times.

[0045] Example 2

[0046] See Figure 1 This embodiment uses a 7-channel mesh model formed by 7 consecutive single channels of a certain type of compressor as an example to describe in detail the analysis method flow of the present invention considering the unsteady aerodynamic forces of blade mistuning. The analysis flow is as follows:

[0047] Step 1: Using the flow channel between two adjacent rotor blades of the compression component as a single channel, select multiple continuously distributed single channels on the entire rotor ring of the compression component to construct a multi-channel mesh model.

[0048] In this embodiment, a 7-channel mesh model of the compressor rotor blades is established.

[0049] It should be noted that in some other embodiments, the number of single channels in the multi-channel mesh model can also be selected as needed, such as 9, 11, etc. The selection principle followed is that at least 7 consecutively distributed single channels are used to construct the multi-channel mesh model, and the number of consecutively distributed single channels is odd.

[0050] Step 2: Use CFD software to perform steady-state calculations on the multi-channel mesh model to obtain the steady flow field and the surface pressure P and surface temperature T of each rotor blade under the multi-channel mesh model;

[0051] In this embodiment, commercial CFD software is used to perform steady-state calculations on a 7-channel mesh model of the compressor, and to obtain the steady flow field inside the compressor and the rotor blade surface pressure P and surface temperature T under the 7-channel model.

[0052] Step 3: Using the surface pressure, surface temperature, and rotor speed of the corresponding rotor blades as the prestress input for modal analysis, the natural frequencies and modal vectors of the rotor blades under the test mode shape are obtained through simulation.

[0053] In this embodiment, a finite element model of the rotor blade is established, and modal analysis including prestress is performed on the rotor blade. The prestress includes the centrifugal force caused by the rotor speed, the aerodynamic force caused by the surface pressure of the rotor blade, and the thermal stress caused by temperature. The natural frequencies of the rotor blade under the test mode shape are then extracted. Modal vectors.

[0054] Step 4: Apply unsteady computational boundary conditions to the multi-channel mesh model, and set the rotor blades in the middle of the multi-channel mesh model as the moving mesh domain, and set the remaining rotor blades as rigid states. Based on the natural frequencies and modal vectors under the test mode shape, use the time-progression-based influence coefficient method to analyze and obtain the modal work of each node diameter of the rotor blades under the test mode shape.

[0055] In this embodiment, unsteady computational boundary conditions are applied to the 7-channel mesh model of the compressor rotor blades constructed in step one. The rotor blade in the middle of the 7-channel mesh model is set as a moving mesh domain, while the remaining 6 rotor blades are set as rigid. The modal work of each node diameter of the rotor blades under the test vibration mode is calculated using the time-progressive influence coefficient method. ,in This refers to the number of single channels in a multi-channel mesh model. , To assess the vibration period of the rotor blades under different vibration modes, To assess the vibration frequency of the rotor blades under the specified mode shape, To assess the phase angle of the rotor blades under the vibration mode, For numerical simulation time, , This represents the integration over the closed surface of the modal forces of the rotor blades. The pressure on the blade surface. To evaluate the modal vectors of the rotor blades under different vibration modes, The normal vector of the rotor blade surface. The surface area of ​​the rotor blades. This is the differential symbol.

[0056] Step 5: The pitch diameter with the minimum modal work of the rotor blade under the test mode shape is defined as the critical pitch diameter. The rotor blade in the middle of the multi-channel mesh model is set as the moving mesh domain, and the other rotor blades are set as rigid. Multi-channel unsteady calculation is carried out under the critical pitch diameter considering the preset detuning conditions of the rotor blade. The pressure, displacement, velocity of the mesh point on the rotor blade surface and the blade surface normal vector corresponding to each mesh point are output at each time step.

[0057] In this embodiment, the preset detuning condition is: the maximum detuning amount of the blade frequency is The sweep frequency of rotor blade vibration is set to , ,in To assess the natural frequencies under different vibration modes, For numerical simulation time, the unsteady calculation results output five pieces of information for each time step: pressure, coordinates, mesh displacement, mesh velocity, and blade surface normal vector at each rotor blade surface mesh point.

[0058] Step 6: Based on the pressure, displacement, velocity, and blade surface normal vector of each grid point on the rotor blade surface at each time step, establish a proxy model between the unsteady aerodynamic forces and vibration displacements of the blade under the critical pitch diameter using the dynamic mode decomposition method. Then, use the fluid-structure interaction method to conduct a dynamic simulation analysis of the rotor blade structure to obtain the unsteady aerodynamic forces and vibration displacement information of the blade at different times.

[0059] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An analytical method for unsteady aerodynamic forces considering blade mistuning, characterized in that, include: Using the flow channel between two adjacent rotor blades of the compression component as a single channel, a multi-channel mesh model is constructed by selecting multiple continuously distributed single channels on the entire rotor ring of the compression component. Steady-state calculations of the multi-channel mesh model were performed using CFD software to obtain the steady flow field and the surface pressure and surface temperature of each rotor blade under the multi-channel mesh model. Using the surface pressure, surface temperature, and rotor speed of the corresponding rotor blades as the prestress input for modal analysis, the natural frequencies and modal vectors of the rotor blades under the test mode shape are obtained through simulation. Unsteady computational boundary conditions are applied to the multi-channel mesh model, and the rotor blades in the middle of the multi-channel mesh model are set as dynamic mesh domains, while the remaining rotor blades are set as rigid states. Based on the natural frequencies and modal vectors under the test mode shape, the modal work of each node diameter of the rotor blades under the test mode shape is obtained by analyzing the influence coefficient method based on time progression. The pitch diameter with the minimum modal work of the rotor blade under the test mode shape is defined as the critical pitch diameter. The rotor blade in the middle of the multi-channel mesh model is set as the moving mesh domain, and the other rotor blades are set as rigid. Multi-channel unsteady calculation is carried out under the critical pitch diameter considering the preset detuning conditions of the rotor blade. The pressure, displacement, velocity and blade surface normal vector of each mesh point on the rotor blade surface are output at each time step. Based on the pressure, displacement, velocity, and blade surface normal vector of each grid point on the rotor blade surface at each time step, a proxy model between the unsteady aerodynamic forces and vibration displacements of the blade under the critical nodal diameter is established using the dynamic mode decomposition method. The rotor blade structure dynamics simulation analysis is carried out using the fluid-structure interaction method to obtain the unsteady aerodynamic forces and vibration displacement information of the blade at different times.

2. The analytical method according to claim 1, characterized in that, Select at least 7 consecutively distributed single channels to construct a multi-channel mesh model, and the number of consecutively distributed single channels must be odd.

3. The analytical method according to claim 1, characterized in that, use Analysis yields modal work of the rotor blades at each pitch diameter under the tested vibration mode. ,in This refers to the number of single channels in a multi-channel mesh model. , To assess the vibration period of the rotor blades under different vibration modes, To assess the vibration frequency of the rotor blades under the specified mode shape, To assess the phase angle of the rotor blades under the vibration mode, For numerical simulation time, , This represents the integration over the closed surface of the modal forces of the rotor blades. The pressure on the blade surface. To evaluate the modal vectors of the rotor blades under different vibration modes, The normal vector of the rotor blade surface. The surface area of ​​the rotor blades. This is the differential symbol.

4. The analytical method according to claim 1, characterized in that, The preset detuning condition is: the maximum detuning amount of the blade frequency is... The sweep frequency of rotor blade vibration is set to , ,in To assess the natural frequencies under different vibration modes, This represents the numerical simulation time.

5. An analytical system for unsteady aerodynamic forces considering blade mistuning, characterized in that, include: The network model building module is used to construct a multi-channel mesh model by selecting multiple continuously distributed single channels on the entire rotor ring of the compression component, taking two adjacent rotor blades of the compression component and the flow channel between them as single channels. The first analysis module is used to perform steady-state calculations on the multi-channel mesh model using CFD software, and to obtain the steady flow field and the surface pressure P and surface temperature T of each rotor blade under the multi-channel mesh model. The second analysis module is used to simulate and obtain the natural frequencies and modal vectors of the rotor blades under the test mode shape by taking the surface pressure, surface temperature and rotor speed of the corresponding rotor blades as the prestress input for modal analysis. The third analysis module is used to apply unsteady computational boundary conditions to the multi-channel mesh model, and set the rotor blades in the middle of the multi-channel mesh model as the moving mesh domain, and set the remaining rotor blades as the rigid state. Based on the natural frequency and modal vector under the test mode, the modal work of each node diameter of the rotor blade under the test mode is obtained by using the influence coefficient method based on time progression. The fourth analysis module defines the critical pitch diameter as the pitch diameter with the minimum modal work of the rotor blade under the test mode shape. The rotor blade in the middle of the multi-channel mesh model is set as a moving mesh domain, and the other rotor blades are set as rigid. Multi-channel unsteady calculations are carried out under the critical pitch diameter considering the preset detuning conditions of the rotor blade. The module outputs the pressure, displacement, velocity of the mesh points on the rotor blade surface and the blade surface normal vector corresponding to each mesh point at each time step. The fifth analysis module is used to establish a proxy model between the unsteady aerodynamic forces and vibration displacements of the blade under the critical nodal diameter based on the pressure, displacement, velocity of the grid points on the rotor blade surface at each time step, as well as the blade surface normal vector corresponding to each grid point. It then uses the fluid-structure interaction method to carry out the dynamic simulation analysis of the rotor blade structure and obtain the unsteady aerodynamic forces and vibration displacement information of the blade at different times.

6. The analysis system according to claim 5, characterized in that, In the network model construction module, at least 7 continuously distributed single channels are selected to construct a multi-channel mesh model, and the number of continuously distributed single channels is odd.

7. The analysis system according to claim 5, characterized in that, In the third analysis module, using Analysis yields modal work of the rotor blades at each pitch diameter under the tested vibration mode. ,in This refers to the number of single channels in a multi-channel mesh model. , To assess the vibration period of the rotor blades under different vibration modes, To assess the vibration frequency of the rotor blades under the specified mode shape, To assess the phase angle of the rotor blades under the vibration mode, For numerical simulation time, , This represents the integration over the closed surface of the modal forces of the rotor blades. The pressure on the blade surface. To evaluate the modal vectors of the rotor blades under different vibration modes, The normal vector of the rotor blade surface. The surface area of ​​the rotor blades. This is the differential symbol.

8. The analysis system according to claim 5, characterized in that, In the fourth analysis module, the preset detuning condition is: the maximum detuning amount of the blade frequency is The sweep frequency of rotor blade vibration is set to , ,in To assess the natural frequencies under different vibration modes, This represents the numerical simulation time.

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