Vibration characteristics analysis method and system of thin-walled stator components based on contact interaction

Abstract

The present invention relates to the field of aero-engine technology, and discloses a method and system for analyzing the vibration characteristics of thin-walled stators based on contact. Based on the matching relationship and relative motion characteristics of adjacent thin-walled stators, the stiffness and modal history of the thin-walled stators are comprehensively considered. An elastic unit is introduced as a simulated stiffness structure, and a simulated assembly is formed with the contacting stator. The direction of relative motion between the target stator and the contacting stator, as well as the points at which the elastic unit applies constraints, is determined based on the vibration mode of the target stator at the test order. Modal analysis of the simulated assembly is then performed to obtain the corresponding vibration characteristics of the target stator and the contacting stator. The present invention can be used to determine whether abnormal engine frequencies are related to coupled vibrations, effectively carry out structural design and fault reproduction, and thus reduce safety hazards caused by vibration in thin-walled stators.

Description

Technical Field

[0001] The invention relates to the technical field of aero-engines and discloses a method and a system for analyzing vibration characteristics of a thin-walled stator component based on contact action. Background Art

[0002] Thin-walled stators in aircraft engines operate in high-temperature environments. To relieve thermal stress, thermal deformation is often not restricted. This results in gaps between adjacent components, affecting vibration amplitude. Furthermore, the vibration characteristics change dynamically as the contact state of each component changes with operating conditions, making it difficult to clearly define the constraint boundaries. The direct consequence of this is that the abnormal frequency signals obtained during engine testing differ significantly from the simulation results, making it impossible to determine whether dangerous resonances exist. Accurately determining the frequencies and modes of thin-walled stators affected by adjacent components is crucial for engine design, testing, and fault reproduction. Summary of the Invention

[0003] The purpose of the present invention is to provide a method and system for analyzing the vibration characteristics of thin-walled stator parts based on contact action, which can accurately obtain the structural vibration characteristics of thin-walled stator parts after being affected by contact with adjacent parts, laying the foundation for conducting vibration characteristics analysis of thin-walled stator parts.

[0004] In order to achieve the above technical effects, the technical solution adopted by the present invention is:

[0005] The vibration characteristics analysis method of thin-walled stator components based on contact action includes:

[0006] Constructing an analytical model of a contact stator and a target stator that come into contact in the radial direction of an aero-engine after vibration in a working state, and analyzing and obtaining the stiffness of the target stator when the contact stator and the target stator come into contact;

[0007] According to the installation method of the contact stator and the target stator in the engine, the vibration boundary conditions of the target stator are applied separately, and the vibration mode of the target stator without interference with the contact stator under the test order is analyzed; the vibration boundary conditions include the constraint position of the target stator, the operating temperature, and the pressure on the inner and outer walls of the target stator;

[0008] Taking the stiffness of the target stator when in contact as the total stiffness, introducing elastic units as a simulated stiffness structure, and evenly distributing the elastic units between the radial gap between the target stator and the contact stator in the analysis model to form a simulated assembly of the target stator and the contact stator;

[0009] The vibration direction and displacement of the vibration mode are extracted, the normal vibration direction of the target stator in the vibration mode is used as the direction of relative motion between the target stator and the contact stator, and the maximum displacement point of the target stator under the vibration mode is used as the constraint point of the elastic unit. The modal analysis of the simulated assembly is carried out under the assessment order to obtain the frequency and vibration mode of the target stator and the contact stator under the assessment order respectively.

[0010] Furthermore, the elastic unit includes a spring, a beam, a single-pull steel cable or a single-compression steel cable.

[0011] Furthermore, when the elastic units are evenly distributed in the analysis model to form the target stator component simulation structure, the number of local displacement peaks in the vibration mode under the assessment order whose displacement is greater than a preset threshold is determined as the number of elastic units.

[0012] Furthermore, the stiffness of each elastic unit is K1 / n, wherein K1 is the stiffness of the target static component when in contact, and n is the number of the elastic units.

[0013] To achieve the above technical effects, the present invention further provides a thin-walled stator component vibration characteristic analysis system based on contact action, which is used to implement the thin-walled stator component vibration characteristic analysis method based on contact action, comprising:

[0014] A stiffness analysis module is used to construct an analysis model of a contact stator and a target stator that come into contact in the radial direction of the aircraft engine after vibration in the working state, and to analyze and obtain the stiffness of the target stator when the contact stator and the target stator come into contact;

[0015] A modal analysis module is used to apply vibration boundary conditions to the target stator separately according to the installation method of the contact stator and the target stator in the engine, and analyze and obtain the vibration mode of the target stator without interference from the contact stator under the test order; the vibration boundary conditions include the constraint position of the target stator, the operating temperature, and the pressure on the inner and outer walls of the target stator;

[0016] An analysis model construction module, wherein the stiffness is the stiffness of the target stator when in contact as the total stiffness, and elastic units are introduced as a simulated stiffness structure. In the analysis model, the elastic units are evenly distributed between the radial gaps between the target stator and the contact stator to form a simulated assembly of the target stator and the contact stator;

[0017] The vibration characteristic analysis module extracts the vibration direction and displacement of the vibration mode, takes the normal vibration direction of the target stator in the vibration mode as the direction of relative motion between the target stator and the contact stator, and takes the maximum displacement point of the target stator under the vibration mode as the constraint point of the elastic unit, performs modal analysis of the simulated assembly under the assessment order, and obtains the frequency and vibration mode of the target stator and the contact stator under the assessment order respectively.

[0018] Furthermore, in the analysis model construction module, the elastic unit includes a spring, a beam, a single-tension steel cable or a single-compression steel cable.

[0019] Furthermore, when the elastic units are evenly distributed in the analysis model in the analysis model to form the target static component simulation structure, the number of local displacement peaks in the vibration mode under the assessment order whose displacement is greater than a preset threshold is determined as the number of elastic units.

[0020] Furthermore, in the analysis model construction module, the stiffness of each elastic unit is K1 / n, where K1 is the stiffness of the target static component when it comes into contact, and n is the number of the elastic units.

[0021] Compared with the prior art, the beneficial effects of the present invention are: the present invention comprehensively considers the matching relationship and relative motion characteristics of thin-walled stator parts, fully considers the stiffness and modal history, and uses parallel elastic units to simulate the contact state of adjacent thin-walled stator components to obtain the vibration characteristics under the corresponding assessment order, which can be used to determine whether the abnormal frequency of the engine is related to the coupled vibration, effectively carry out structural design and fault reproduction, thereby reducing the safety hazards caused by vibration of thin-walled stator parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Flowchart of the vibration characteristics analysis method of a thin-walled stator based on contact in Example 1;

[0023] Figure 2 This is a structural block diagram of the vibration characteristics analysis system for thin-walled stator components based on contact action in Example 1;

[0024] Figure 3 Schematic diagram of the positional relationship between two adjacent thin-walled stator components in Example 1 or 2;

[0025] Figure 4 Schematic diagram of the structure of a simulated assembly in which the elastic unit is a spring in Example 1 or 2;

[0026] Figure 5 Schematic diagram of the structure of the simulated assembly in which the elastic unit is a beam in Example 1;

[0027] Figure 6Schematic diagram of the structure of a simulated assembly in which the elastic unit is a steel cable in Example 1;

[0028] Figure 7 The vibration mode diagram of the target stator under the test order obtained by applying the vibration boundary condition analysis of the target stator alone in Example 2;

[0029] Among them, 1. Target static component; 2. Contact static component; 3. Spring; 4. Elastic unit constraint point; 5. Beam; 6. Steel cable; 7. Stiffness analysis module; 8. Modal analysis module; 9. Analysis model construction module; 10. Vibration characteristics analysis module. DETAILED DESCRIPTION

[0030] The present invention will be described in further detail below with reference to the embodiments and accompanying drawings. However, this should not be construed as limiting the scope of the present invention to the following embodiments, as all technologies implemented based on the present invention fall within the scope of the present invention.

[0031] Example 1

[0032] See also Figures 1 to 6 , the vibration characteristics analysis method of thin-walled stator based on contact action, including:

[0033] Constructing an analytical model of a contact stator 2 and a target stator 1 that come into contact in the radial direction of the aircraft engine after vibration in a working state, and analyzing and obtaining the stiffness of the target stator 1 when the contact stator 2 and the target stator 1 come into contact;

[0034] According to the installation method of the contact stator 2 and the target stator 1 in the engine, the vibration boundary conditions of the target stator 1 are applied separately, and the vibration mode of the target stator 1 without interference from the contact stator 2 under the test order is analyzed; the vibration boundary conditions include the restraint position of the target stator 1, the operating temperature, and the pressure on the inner and outer walls of the target stator 1;

[0035] The stiffness of the target stator 1 when in contact is taken as the total stiffness, and elastic units are introduced as a simulated stiffness structure. In the analysis model, the elastic units are evenly distributed between the radial gaps between the target stator 1 and the contact stator 2 to form a simulated assembly of the target stator 1 and the contact stator 2.

[0036] The vibration direction and displacement of the vibration mode are extracted, the normal vibration direction of the target stator 1 in the vibration mode is used as the direction of relative motion between the target stator 1 and the contact stator 2, and the maximum displacement point of the target stator 1 under the vibration mode is used as the elastic unit to apply the constraint point 4, and the modal analysis of the simulated assembly is carried out under the assessment order to obtain the frequency and vibration mode of the target stator 1 and the contact stator 2 under the assessment order respectively.

[0037] In this embodiment, based on the matching relationship and relative motion characteristics of adjacent thin-walled stators, the stiffness and modal history of the thin-walled stators are comprehensively considered. By introducing an elastic unit as a simulated stiffness structure, and according to the vibration mode of the target stator 1 under the test order, the direction of relative motion between the target stator 1 and the contact stator 2 and the elastic unit applying constraint point 4 are determined, so as to carry out modal analysis of the simulated assembly, and obtain the corresponding vibration characteristics of the target stator 1 and the contact stator 2 respectively, which can be used to determine whether the abnormal frequency of the engine is related to the coupled vibration, effectively carry out structural design and fault reproduction, and thus reduce the safety hazards caused by vibration of thin-walled stators.

[0038] In this embodiment, the elastic unit includes a spring 3, a beam 5, a single-pull steel cable 6 or a single-compression steel cable 6; wherein the elastic unit is a simulated assembly structure of the spring 3 such as Figure 4 As shown, the elastic unit is the simulated assembly structure of beam 5 as shown in Figure 5 As shown, the elastic unit is a simulated assembly structure of the steel cable 6 as shown in FIG. Figure 6 As shown, the state of the steel cable 6 can be either a tension state or a compression state, which is specifically determined according to the relative vibration displacement between the target stator component 1 and the contact stator component 2 .

[0039] Based on the same inventive concept, this embodiment further provides a thin-walled stator component vibration characteristic analysis system based on contact action, which is used to implement the thin-walled stator component vibration characteristic analysis method based on contact action, including:

[0040] The stiffness analysis module 7 is used to construct an analysis model of the contact stator 2 and the target stator 1 that come into contact in the radial direction of the aircraft engine after vibration in the working state, and to analyze and obtain the stiffness of the target stator 1 when the contact stator 2 and the target stator 1 come into contact;

[0041] A modal analysis module 8 is configured to apply vibration boundary conditions to the target stator 1 independently according to the installation method of the contact stator 2 and the target stator 1 in the engine, and analyze and obtain the vibration mode of the target stator 1 without interference from the contact stator 2 under the test order; the vibration boundary conditions include the constraint position of the target stator 1, the operating temperature, and the pressure on the inner and outer walls of the target stator 1;

[0042] Analysis model construction module 9, which takes the stiffness of the target stator 1 when in contact as the total stiffness, introduces elastic units as a simulated stiffness structure, and evenly distributes the elastic units between the radial gap between the target stator 1 and the contact stator 2 in the analysis model to form a simulated assembly of the target stator 1 and the contact stator 2;

[0043] The vibration characteristic analysis module 10 extracts the vibration direction and displacement of the vibration mode, takes the normal vibration direction of the target stator 1 in the vibration mode as the direction of relative movement between the target stator 1 and the contact stator 2, and takes the maximum displacement point of the target stator 1 under the vibration mode as the elastic unit to apply the constraint point 4, carries out the modal analysis of the simulated assembly under the assessment order, and obtains the frequency and vibration mode of the target stator 1 and the contact stator 2 under the assessment order respectively.

[0044] Example 2

[0045] like Figure 3 This is a schematic diagram of two adjacent thin-walled stators. There is a small gap between the contact stator 2 and the target stator 1, and they will come into contact after vibration in the working state. The vibration characteristics of the two thin-walled stators are analyzed by the following steps:

[0046] Step 1: construct an analytical model of the contact stator 2 and the target stator 1 that will come into contact in the radial direction of the aircraft engine after vibration in the working state, and analyze and obtain the stiffness of the target stator 1 when the contact stator 2 and the target stator 1 come into contact;

[0047] In this embodiment, Figure 3 As shown in FIG, since the upper surface of the target stator 1 and the lower surface of the contact stator 2 will come into contact due to vibration, the target stator 1 is obtained by the finite element analysis method. Figure 3 The stiffness K1 of the contact in direction A and the contact stator 2 are shown in FIG. Figure 3 The contact stiffness K2 in the B direction is shown.

[0048] Step 2: According to the installation method of the contact stator 2 and the target stator 1 in the engine, the vibration boundary conditions of the target stator 1 are applied separately, and the vibration mode of the target stator 1 without interference from the contact stator 2 under the test order is analyzed; the vibration boundary conditions include the restraint position of the target stator 1, the operating temperature, and the pressure on the inner and outer walls of the target stator 1;

[0049] In this embodiment, first, according to the installation method of the target stator 1 in the engine (for determining the constraint position of the target stator 1) and the working conditions of the target stator 1 at the test order (including the working temperature and the pressure on the inner and outer walls of the target stator 1), the vibration boundary conditions of the target stator 1 are applied separately, and the mode of the target stator 1 is calculated to obtain the vibration shape of the target stator 1 at the test order (such as Figure 7 shown).

[0050] Step 3: Taking the stiffness of the target stator 1 when in contact as the total stiffness, introduce elastic units as a simulated stiffness structure, and evenly distribute the elastic units between the radial gap between the target stator 1 and the contact stator 2 in the analysis model to form a simulated assembly of the target stator 1 and the contact stator 2;

[0051] In this embodiment, Figure 4 The spring 3 shown is used as an elastic unit to simulate the stiffness structure, and the initial stiffness is K1, and the local displacement peak value (such as Figure 7 The number n of black dots in the figure is the number of elastic units. The n elastic units are evenly distributed between the target stator 1 and the contact stator 2. The stiffness of each elastic unit is K1 / n, forming a simulated assembly.

[0052] Step 4. Extract the vibration direction and displacement of the vibration mode, use the normal vibration direction of the target stator 1 in the vibration mode as the direction of relative movement between the target stator 1 and the contact stator 2, and use the maximum displacement point of the target stator 1 under the vibration mode as the elastic unit to apply the constraint point 4, carry out the modal analysis of the simulated assembly under the assessment order, and obtain the frequency and vibration mode of the target stator 1 and the contact stator 2 under the assessment order respectively.

[0053] In this embodiment, the normal vibration direction of the target stator 1 in step 2 is used as the direction of relative movement between the target stator 1 and the contact stator 2, and the point of maximum displacement of the target stator 1 is used as the elastic unit to apply the constraint point 4, and the modal analysis of the simulated assembly is carried out under the test order to obtain the frequency and vibration mode of the target stator 1 and the contact stator 2 under the test order respectively.

[0054] The above are only 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 in the scope of protection of the present invention.

Claims

1. A method for analyzing the vibration characteristics of thin-walled stators based on contact action, characterized in that: include: Constructing an analytical model of a contact stator and a target stator that come into contact in the radial direction of an aero-engine after vibration in a working state, and analyzing and obtaining the stiffness of the target stator when the contact stator and the target stator come into contact; According to the installation method of the contact stator and the target stator in the engine, the vibration boundary conditions of the target stator are applied separately, and the vibration mode of the target stator without interference with the contact stator under the test order is analyzed; the vibration boundary conditions include the constraint position of the target stator, the operating temperature, and the pressure on the inner and outer walls of the target stator; Taking the stiffness of the target stator when in contact as the total stiffness, introducing elastic units as a simulated stiffness structure, and evenly distributing the elastic units between the radial gap between the target stator and the contact stator in the analysis model to form a simulated assembly of the target stator and the contact stator; The vibration direction and displacement of the vibration mode are extracted, the normal vibration direction of the target stator in the vibration mode is used as the direction of relative motion between the target stator and the contact stator, and the maximum displacement point of the target stator under the vibration mode is used as the constraint point of the elastic unit. The modal analysis of the simulated assembly is carried out under the assessment order to obtain the frequency and vibration mode of the target stator and the contact stator under the assessment order respectively.

2. The method for analyzing vibration characteristics of thin-walled stator components based on contact action according to claim 1 is characterized in that: The elastic unit includes a spring, a beam, a single-pull steel cable or a single-compression steel cable.

3. The method for analyzing vibration characteristics of thin-walled stator components based on contact action according to claim 1, characterized in that: When the elastic units are evenly distributed in the analysis model to form the target stator component simulation structure, the number of local displacement peaks with displacements greater than a preset threshold in the vibration mode under the assessment order is determined as the number of elastic units.

4. The method for analyzing vibration characteristics of thin-walled stator components based on contact action according to claim 3 is characterized in that: The stiffness of each elastic unit is K1 / n, where K1 is the stiffness of the target static component when it comes into contact, and n is the number of the elastic units.

5. A thin-walled stator vibration characteristic analysis system based on contact action, used to implement the thin-walled stator vibration characteristic analysis method based on contact action according to claim 1, characterized in that: include: A stiffness analysis module is used to construct an analysis model of a contact stator and a target stator that come into contact in the radial direction of the aircraft engine after vibration in the working state, and to analyze and obtain the stiffness of the target stator when the contact stator and the target stator come into contact; A modal analysis module is used to apply vibration boundary conditions to the target stator separately according to the installation method of the contact stator and the target stator in the engine, and analyze and obtain the vibration mode of the target stator without interference from the contact stator under the test order; the vibration boundary conditions include the constraint position of the target stator, the operating temperature, and the pressure on the inner and outer walls of the target stator; An analysis model construction module, wherein the stiffness is the stiffness of the target stator when in contact as the total stiffness, and elastic units are introduced as a simulated stiffness structure. In the analysis model, the elastic units are evenly distributed between the radial gaps between the target stator and the contact stator to form a simulated assembly of the target stator and the contact stator; The vibration characteristic analysis module extracts the vibration direction and displacement of the vibration mode, takes the normal vibration direction of the target stator in the vibration mode as the direction of relative motion between the target stator and the contact stator, and takes the maximum displacement point of the target stator under the vibration mode as the constraint point of the elastic unit, performs modal analysis of the simulated assembly under the assessment order, and obtains the frequency and vibration mode of the target stator and the contact stator under the assessment order respectively.

6. The thin-walled stator vibration characteristic analysis system based on contact action according to claim 5 is characterized in that: In the analysis model building module, the elastic unit includes a spring, a beam, a single-tension steel cable or a single-compression steel cable.

7. The thin-walled stator vibration characteristic analysis system based on contact action according to claim 5 is characterized in that: In the analysis model construction module, when the elastic units are evenly distributed in the analysis model to form the target static component simulation structure, the number of local displacement peaks in the vibration mode under the assessment order whose displacement is greater than a preset threshold is determined as the number of elastic units.

8. The thin-walled stator vibration characteristic analysis system based on contact action according to claim 7 is characterized in that: In the analysis model construction module, the stiffness of each elastic unit is K1 / n, where K1 is the stiffness of the target static component when it comes into contact, and n is the number of the elastic units.

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