Material parameter acquisition method and device, electronic equipment and storage medium

Abstract

The invention provides a material parameter obtaining method and device, equipment and a medium, and relates to the technical field of material performance detection.The method comprises the steps that response of an entity vibration test is used as reference to adjust and simulate damping material parameters of the vibration test, so that a test sample finite element model obtains the damping material parameters of the vibration test on the basis of the finally-determined damping material parameters and base material parameters; and the vibration response same as that of a test sample entity vibration test can be shown. Finally obtained damping material parameters serve as material parameters of the viscoelastic damping material, so that when damping distribution design and NVH performance design are conducted on a vehicle, the introduced material parameters of the viscoelastic damping material can effectively represent the damping performance of the damping material when the damping material is actually applied to a vehicle body metal plate; and accurate basic data is provided for subsequent application of the damping material.

Description

Technical Field

[0001] The present application relates to the field of material performance testing, and in particular to a method, device, electronic device and storage medium for acquiring material parameters of a viscoelastic damping material. Background Art

[0002] Viscoelastic damping materials are applied to the body sheet metal by spraying or high-temperature baking, which can achieve good vibration reduction and noise reduction effects and improve the vibration and noise level of the car. The material parameters of viscoelastic damping materials, such as the loss factor of viscoelastic damping materials, are important parameters for measuring their vibration reduction effects. The higher the loss factor, the more the damping material dissipates the vibration energy during the vibration of the body sheet metal, and the more obvious the vibration reduction and noise reduction effects are.

[0003] Material parameters are an important basis for the selection of viscoelastic damping materials. Obtaining this parameter is conducive to selecting materials with better vibration reduction effects in the early stage of design, so that the vibration and noise inside the vehicle can reach a better level. Knowing the material parameters of the damping material, the structural vibration reduction performance of the material can be estimated, and the vibration reduction and noise reduction level of the whole vehicle can be estimated in the design stage, providing an important basis for the design of the vibration and noise performance of the whole vehicle.

[0004] Therefore, how to obtain the material parameters of viscoelastic damping materials with high accuracy in order to accurately understand the vibration reduction performance of viscoelastic damping materials in practical applications and provide accurate and effective reference data for vehicle sound quality development has become an urgent problem to be solved. Summary of the invention

[0005] Based on this, it is necessary to provide a material parameter acquisition method, device, electronic device and storage medium for viscoelastic damping materials to address the above-mentioned technical problems. The equipment involved is simple and easy to operate, and can provide more accurate material parameters for damping optimization distribution design and automotive NVH performance prediction.

[0006] A method for obtaining material parameters of a viscoelastic damping material comprises: obtaining material parameters of a substrate in a test sample as substrate material parameters of a finite element model of the test sample, wherein the test sample is a substrate sample provided with a free damping layer of the viscoelastic damping material; in the process of performing a simulation vibration test on the finite element model of the test sample under a preset analysis condition, adjusting the damping material parameters of the finite element model of the test sample until the finite element model of the test sample responds to a second vibration acceleration curve that matches a first vibration acceleration curve, wherein the first vibration acceleration curve is obtained by performing a physical vibration test on the test sample under the preset analysis condition; and determining the damping material parameters currently corresponding to the finite element model of the test sample as the material parameters of the viscoelastic damping material.

[0007] In an embodiment of the present application, the material parameters of the substrate are: when a fourth vibration acceleration curve matching the third vibration acceleration curve is obtained during a simulation vibration test of the finite element model of the substrate sample under the preset analysis conditions, the material parameters of the finite element model of the substrate sample, and the third vibration acceleration curve is obtained by performing a physical vibration test on the substrate sample under the preset analysis conditions.

[0008] In an embodiment of the present application, the damping material parameters include a loss factor. During the process of performing a simulation vibration test on the finite element model of the test sample, the material parameters of the finite element model of the test sample are adjusted, including: determining a first acceleration amplitude corresponding to a target order resonance frequency in the first vibration acceleration curve; determining a second acceleration amplitude corresponding to the target order resonance frequency in the second vibration acceleration curve; if the second acceleration amplitude is greater than the first acceleration amplitude, increasing the loss factor corresponding to the frequency range where the target order resonance frequency is located under the finite element model of the test sample; if the second acceleration amplitude is less than the first acceleration amplitude, decreasing the loss factor corresponding to the frequency range where the target order resonance frequency is located under the finite element model of the test sample.

[0009] In an embodiment of the present application, the damping material parameters also include an elastic modulus; in the process of performing a simulation vibration test on the finite element model of the test sample, adjusting the material parameters of the finite element model of the test sample also includes: if the frequency value of the target order resonance frequency in the second vibration acceleration curve is less than the frequency value of the target order resonance frequency in the first vibration acceleration curve, then increasing the elastic modulus of the finite element model of the test sample; if the frequency value of the target order resonance frequency in the second vibration acceleration curve is greater than the frequency value of the target order resonance frequency in the first vibration acceleration curve, then decreasing the elastic modulus of the finite element model of the test sample.

[0010] In the embodiment of the present application, the target order resonance frequency is a first order resonance frequency and / or a second order resonance frequency.

[0011] In an embodiment of the present application, whether the first vibration acceleration curve matches the second vibration acceleration curve is determined in the following manner: if the frequency difference corresponding to the first-order resonance frequency between the first vibration acceleration curve and the second vibration acceleration curve is less than the first error threshold, the frequency difference corresponding to the second-order resonance frequency is less than the second error threshold, the acceleration amplitude difference corresponding to the first-order vibration frequency is less than the third error threshold, and the acceleration amplitude difference corresponding to the second-order vibration frequency is less than the fourth error threshold, then it is determined that the first vibration acceleration curve matches the second vibration acceleration curve.

[0012] In the embodiment of the present application, the test sample is the composite cantilever damping beam, and the substrate sample is a cantilever steel beam.

[0013] In an embodiment of the present application, the preset analysis condition includes applying an exciting force with a continuously changing frequency to a preset force application point of the sample, and collecting the vibration acceleration of the sample at a preset collection point.

[0014] A parameter acquisition device for a viscoelastic damping material comprises: an acquisition module for acquiring material parameters of a substrate in a test sample as the substrate material parameters of a finite element model of the test sample, wherein the test sample is a substrate sample provided with a free damping layer of the viscoelastic damping material; a parameter adjustment module for adjusting the damping material parameters of the finite element model of the test sample during a simulation vibration test of the finite element model of the test sample under a preset analysis condition, until the finite element model of the test sample responds to a second vibration acceleration curve matching a first vibration acceleration curve, wherein the first vibration acceleration curve is obtained by performing a physical vibration test on the test sample under the preset analysis condition; and a parameter determination module for determining the damping material parameters currently corresponding to the finite element model of the test sample as the material parameters of the viscoelastic damping material. .

[0015] In an embodiment of the present application, the material parameters of the substrate are: when a fourth vibration acceleration curve matching the third vibration acceleration curve is obtained during a simulation vibration test of the finite element model of the substrate sample under the preset analysis conditions, the material parameters of the finite element model of the substrate sample, and the third vibration acceleration curve is obtained by performing a physical vibration test on the substrate sample under the preset analysis conditions.

[0016] In an embodiment of the present application, the damping material parameters include a loss factor, and the parameter adjustment module is used to: determine a first acceleration amplitude corresponding to a target order resonance frequency in the first vibration acceleration curve; determine a second acceleration amplitude corresponding to the target order resonance frequency in the second vibration acceleration curve; if the second acceleration amplitude is greater than the first acceleration amplitude, increase the loss factor corresponding to the frequency range where the target order resonance frequency is located under the finite element model of the test sample; if the second acceleration amplitude is less than the first acceleration amplitude, decrease the loss factor corresponding to the frequency range where the target order resonance frequency is located under the finite element model of the test sample.

[0017] In an embodiment of the present application, the damping material parameters also include an elastic modulus; the parameter adjustment module is used to: if the frequency value of the target order resonance frequency in the second vibration acceleration curve is less than the frequency value of the target order resonance frequency in the first vibration acceleration curve, then increase the elastic modulus of the finite element model of the test sample; if the frequency value of the target order resonance frequency in the second vibration acceleration curve is greater than the frequency value of the target order resonance frequency in the first vibration acceleration curve, then decrease the elastic modulus of the finite element model of the test sample.

[0018] In the embodiment of the present application, the target order resonance frequency is a first order resonance frequency and / or a second order resonance frequency.

[0019] In an embodiment of the present application, whether the first vibration acceleration curve matches the second vibration acceleration curve is determined in the following manner: if the frequency difference corresponding to the first-order resonance frequency between the first vibration acceleration curve and the second vibration acceleration curve is less than the first error threshold, the frequency difference corresponding to the second-order resonance frequency is less than the second error threshold, the acceleration amplitude difference corresponding to the first-order vibration frequency is less than the third error threshold, and the acceleration amplitude difference corresponding to the second-order vibration frequency is less than the fourth error threshold, then it is determined that the first vibration acceleration curve matches the second vibration acceleration curve.

[0020] In the embodiment of the present application, the test sample is the composite cantilever damping beam, and the substrate sample is a cantilever steel beam.

[0021] In an embodiment of the present application, the preset analysis condition includes applying an exciting force with a continuously changing frequency to a preset force application point of the sample, and collecting the vibration acceleration of the sample at a preset collection point.

[0022] An electronic device comprises a memory, a processor and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the method for obtaining material parameters of a viscoelastic damping material as described in any of the above embodiments are implemented.

[0023] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of the method for obtaining material parameters of a viscoelastic damping material as described in any of the above embodiments.

[0024] In summary, the material parameter acquisition method of the viscoelastic damping material proposed in the present application first obtains the material parameters of the substrate in the test sample, so as to fix the substrate material parameters of the finite element model of the test sample as the material parameters of the substrate in the test sample, thereby setting the substrate material parameters with higher accuracy for the finite element model of the test sample, avoiding the influence of the error of the substrate material parameters on the vibration response of the simulated vibration test, and in addition, under the same preset analysis conditions, obtain the first vibration acceleration curve output by the physical vibration test and the second vibration acceleration curve output by the simulated vibration test, so that the variables between the simulated vibration test and the physical vibration test can be controlled to the maximum extent on the damping material parameters of the finite element model of the test sample, so that the damping material parameters finally obtained can better adapt to the response curve of the physical vibration test. Then, by adjusting the damping material parameters of the finite element model of the test sample, the second vibration acceleration curve output by the simulated vibration test of the finite element model of the test sample is adjusted until a second vibration acceleration curve matching the first vibration acceleration curve is obtained, and the damping material parameters of the finite element model of the test sample at this time are determined as the material parameters of the viscoelastic damping material. The present application uses the response of the physical vibration test as a reference to adjust the damping material parameters of the simulated vibration test, so that the finite element model of the test sample can exhibit the same vibration response as the physical vibration test of the test sample based on the final determined damping material parameters and substrate material parameters. The final damping material parameters are used as the material parameters of the viscoelastic damping material, so that when designing the damping distribution and NVH performance of the vehicle, the material parameters of the referenced viscoelastic damping material can effectively characterize the vibration reduction performance of the damping material when it is actually applied to the body sheet metal, providing accurate basic data for the subsequent application of the damping material. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0026] Figure 1 is a flow chart of a method for obtaining material parameters of a viscoelastic damping material according to an exemplary embodiment of the present application;

[0027] Figure 2 is a schematic diagram of a physical vibration test model in a method for obtaining material parameters of a viscoelastic damping material according to another exemplary embodiment of the present application;

[0028] Figure 3 is a flow chart of a method for obtaining material parameters of a viscoelastic damping material according to another exemplary embodiment of the present application;

[0029] Figure 4 is a comparison diagram of vibration acceleration curves of the cantilever steel beam in the embodiment of the present application in the simulation vibration test and the physical vibration test;

[0030] Figure 5 is a comparison diagram of vibration acceleration curves of the composite cantilever damping beam in the embodiment of the present application in the simulation vibration test and the physical vibration test;

[0031] Figure 6 is a schematic block diagram of a material parameter acquisition device for a viscoelastic damping material according to another exemplary embodiment of the present application;

[0032] Figure 7 It is a schematic block diagram of an electronic device according to an exemplary embodiment of the present application. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. The embodiments described by reference to the drawings are exemplary and are intended to be used to explain the present application, and cannot be understood as limiting the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0034] It should be understood that when used in the present specification and the appended claims, the term "comprising" indicates the presence of described features, integers, steps, operations, but does not exclude the presence or addition of one or more other features, integers, steps, operations and / or groups thereof.

[0035] It should also be understood that the term "and / or" used in the present description and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

[0036] As used in the present specification and the appended claims, the term "if" may be interpreted as "when" or "upon" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrase "if it is determined" or "if [described condition or event] is detected" may be interpreted as meaning "upon determination" or "in response to determining" or "upon detection of [described condition or event]" or "in response to detecting [described condition or event]", depending on the context.

[0037] In addition, in the description of the present specification and the appended claims, the terms "first", "second", "third", etc. are only used to distinguish the descriptions and cannot be understood as indicating or implying relative importance.

[0038] References to "one embodiment" or "some embodiments" etc. described in the present specification mean that one or more embodiments of the present invention include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, the phrases "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. appearing in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0039] The present invention can be applied to performance testing and distribution optimization design of automotive viscoelastic damping materials, selection of viscoelastic damping materials before application, and vehicle NVH performance evaluation, so as to provide material parameters of the viscoelastic damping materials, which are more in line with the performance of the viscoelastic damping materials in actual applications and have higher accuracy.

[0040] Figure 1 is a flow chart of a method for obtaining material parameters of a viscoelastic damping material according to an exemplary embodiment of the present application. Figure 1 As shown, the method comprises the following steps:

[0041] S101, obtaining material parameters of a substrate in a test sample as substrate material parameters of a finite element model of the test sample, wherein the test sample is a substrate sample provided with a free damping layer of the viscoelastic damping material.

[0042] The test sample is a sample compounded with a damping material, such as a free damping layer of a viscoelastic damping material is arranged on a substrate / base material sample. That is, after the free damping layer of the viscoelastic damping material is arranged on the base material sample, the test sample is obtained.

[0043] The substrate sample can be a sample of a metal material, such as a cantilever steel beam. The cantilever steel beam has a simple structure, and participating in the test as a substrate sample makes the test results stable, ensuring the validity and accuracy of the results. The corresponding material parameters of the above-mentioned substrate are the material parameters of steel.

[0044] The material parameters involved in this application can be understood as mechanical parameters that can reflect the material stress and strain properties or the structural vibration properties or vibration reduction properties.

[0045] After the finite element model of the test sample is constructed, before starting the simulated vibration test, it is necessary to set the relevant parameters of the finite element model of the test sample to limit the basic performance of the finite element model of the test sample on which the simulated vibration test is carried out. The above-mentioned substrate material parameter is one of the parameters that need to be set. The value of the substrate material parameter is set to the value of the material parameter of the substrate in the test sample. In addition, the initial value of the damping material parameter of the finite element model of the test sample can be set to any value as needed, and this application does not limit it.

[0046] S102, during a simulation vibration test on the finite element model of the test sample under a preset analysis condition, adjusting the damping material parameters of the finite element model of the test sample until the finite element model of the test sample responds to a second vibration acceleration curve that matches the first vibration acceleration curve, wherein the first vibration acceleration curve is obtained by performing a physical vibration test on the test sample under the preset analysis condition.

[0047] The present application performs a physical vibration test on the test sample and a simulated vibration test on the finite element model of the test sample under the same analysis conditions (i.e., the preset analysis conditions) to eliminate interference from external factors, so that the damping material parameters set for the finite element model of the test sample become the only independent variable in the parameter adjustment process, so as to enhance the accuracy of the damping material parameters finally obtained.

[0048] In the physical vibration test and the simulated vibration test, excitation is applied to the test sample and the finite element model of the test sample with fixed substrate material parameters, and the test sample and the finite element model of the test sample will show a vibration response. The present application sets an acceleration sensor at a preset position point to collect the vibration acceleration curve corresponding to the test sample (expressed as the first vibration acceleration curve in the present application), and outputs the vibration acceleration curve of the finite element model of the test sample at the preset position point through simulation software (expressed as the second vibration acceleration curve in the present application).

[0049] When the second vibration acceleration curve obtained in the simulation process matches the first vibration acceleration curve, the simulation is terminated. When the second vibration acceleration curve obtained in the simulation process does not match the first vibration acceleration curve, the damping material parameters of the finite element model of the test sample are adjusted. After the parameters are adjusted, the damping material parameters of the finite element model of the test sample are re-simulated and vibrated under the preset analysis conditions, and it is re-determined whether the newly obtained second vibration acceleration curve matches the first vibration acceleration curve. Repeat this process until the second vibration acceleration curve that matches the first vibration acceleration curve is obtained, and then the simulation is terminated.

[0050] S103, determining the material parameters currently corresponding to the finite element model of the test sample as the material parameters of the viscoelastic damping material.

[0051] After the simulation is completed, the damping material parameters currently corresponding to the finite element model of the test sample are used as the material parameters of the viscoelastic damping material.

[0052] This application fixes the substrate material parameters of the finite element model of the test sample to the material parameters of the substrate in the test sample, and adjusts the damping material parameters of the finite element model of the test sample in combination with the response curve of the physical vibration test, until the finite element model of the test sample can respond to a vibration acceleration curve that matches the response curve of the physical vibration test. Among them, the initial value of the damping material parameter of the finite element model of the test sample can be set to any initial value as needed, and this application does not limit it.

[0053] In summary, the present application proposes a method for obtaining material parameters of a viscoelastic damping material. First, the material parameters of the substrate in the test sample are obtained to fix the material parameters of the substrate of the finite element model of the test sample as the material parameters of the substrate in the test sample, thereby setting the substrate material parameters with higher accuracy for the finite element model of the test sample, avoiding the influence of the error of the substrate material parameters on the vibration response of the simulated vibration test, and in addition, under the same preset analysis conditions, the first vibration acceleration curve output by the physical vibration test and the second vibration acceleration curve output by the simulated vibration test are obtained, so that the variables between the simulated vibration test and the physical vibration test can be controlled to the maximum extent on the damping material parameters, so that the damping material parameters finally obtained can better adapt to the response curve of the physical vibration test. Then, by adjusting the damping material parameters of the finite element model of the test sample, the second vibration acceleration curve output by the simulated vibration test of the finite element model of the test sample is adjusted until a second vibration acceleration curve matching the first vibration acceleration curve is obtained, and the damping material parameters of the finite element model of the test sample at this time are determined as the material parameters of the viscoelastic damping material. The present application uses the response of the actual vibration test as a reference to adjust the damping material parameters of the simulated vibration test, so that the finite element model of the test sample can exhibit the same vibration response as the actual vibration test of the test sample based on the final determined damping material parameters and substrate material parameters. The final damping material parameters are used as the material parameters of the viscoelastic damping material, so that when designing the damping distribution and NVH performance of the vehicle, the material parameters of the referenced viscoelastic damping material can effectively characterize the vibration reduction performance of the damping material when it is actually used on the body panels, and provide accurate basic data for the subsequent application of the damping material.

[0054] In practice, the material parameters of the substrate can be obtained by testing with testing equipment, or the default material parameters for the substrate in the industry can be directly used.

[0055] In order to improve the accuracy of the material parameters of the damping material finally obtained, this application proposes that the material parameters of the substrate can be obtained by the following methods:

[0056] Under the above-mentioned preset analysis conditions, a simulated vibration test is performed on the finite element model of the substrate sample. During the simulated vibration test, the finite element model of the substrate sample will show a vibration response after being stimulated. For example, the simulation software will output a vibration acceleration curve, which is the fourth vibration acceleration curve defined in this application. After obtaining the fourth vibration acceleration curve, this application can determine whether the fourth vibration acceleration curve matches the third vibration acceleration curve. If it matches, the material parameters of the finite element model of the substrate sample at this time are used as the material parameters of the substrate sample; if it does not match, the material parameters of the finite element model of the substrate sample are adjusted. After the material parameters are adjusted, the simulated vibration test is performed again under the preset analysis conditions to re-obtain the fourth vibration acceleration curve, and this cycle is repeated until the finite element model of the substrate sample responds to a fourth vibration acceleration curve that matches the third vibration acceleration curve.

[0057] The third vibration acceleration curve is obtained by performing a physical vibration test on the substrate sample under the preset analysis conditions.

[0058] It should be noted that the process of adjusting the damping material parameters of the finite element model of the substrate sample based on the third vibration acceleration curve in the present application can refer to the process of adjusting the damping material parameters of the finite element model of the test sample based on the first vibration acceleration curve, and will not be repeated here.

[0059] In this way, the substrate material parameters set for the finite element model of the test sample can meet the vibration reduction performance of the substrate in actual application, ensuring the accuracy of the substrate material parameters, thereby further improving the accuracy of the final damping material parameters.

[0060] The preset analysis conditions include applying an exciting force with a continuously changing frequency to a preset force application point of the test sample, and collecting the vibration acceleration of the test sample at a preset collection point.

[0061] For example, in a physical vibration test, a vertical hammer can be used to strike the preset force point for excitation. In a simulated vibration test, a vertical hammer is applied to the same preset force point on the finite element model of the test sample for excitation. The force hammer striking excitation includes exciting forces at all frequencies. Optionally, a vibration acceleration acquisition device or a vibration response test device can be set at a preset acquisition point. Furthermore, the frequency band to be observed can be set in the test equipment, that is, the vibration response result of the frequency band is output. In this way, the material parameters in different frequency bands can be adjusted accordingly, and finally the material parameters of the damping material in different frequency bands can be obtained, thereby avoiding repeated tests by switching the excitation frequency to obtain the material parameters in different frequency bands, thereby enhancing the convenience and applicability of the material parameter acquisition method of the present application.

[0062] For example, using a cantilever steel beam as the base material sample, set up Figure 2The physical vibration test model shown in Figure 2 As shown in the figure, the cantilever steel beam is L in length, the fixed end is the starting zero point, and the hammer hits the cantilever beam. At the cantilever beam, a unit force of 1N is applied; Arrange an acceleration sensor at the point to test the vibration response of the point and output an acceleration vibration response curve Test_curve, that is, the third vibration acceleration curve in the present application;

[0063] When conducting a simulated vibration test on a cantilever steel beam, a finite element model of a cantilever steel beam with a length of L is established, and a 2D shell element is used to simulate the elastic steel beam. The same force application points, response collection points, and excitation forces as those in the physical vibration test are set. After conducting a simulated vibration test on the finite element model, the output is based on the cantilever beam. The vibration acceleration response curve CAE_curve obtained by finite element calculation at is the fourth vibration acceleration curve in this application.

[0064] The material parameters of the steel beam are adjusted based on the third vibration acceleration curve until the cantilever steel beam finite element model outputs a fourth vibration acceleration curve that matches the third vibration acceleration curve, and the material parameters finally corresponding to the cantilever steel beam finite element model are used as the material parameters of the steel beam.

[0065] Furthermore, the cantilever steel beam was baked and the free damping layer was pasted to form a composite cantilever damping beam. The same analysis conditions as the cantilever steel beam entity vibration test were set. A 1N load excitation force is applied to the composite cantilever damping beam. An acceleration sensor is set at the location to test and collect the acceleration-time vibration response curve Complex_Test_Curve of the composite cantilever damping beam, that is, the first vibration acceleration curve of the present application;

[0066] During the simulation vibration test, based on the finite element model of the cantilever steel beam, a free damping layer finite element model with the same node as the steel beam is established, and a 2D shell element is used to simulate the free damping layer to form a composite cantilever damping beam finite element model. The steel beam material parameters determined by the cantilever steel beam entity vibration test and the simulation vibration test are loaded, and the same analysis conditions as the cantilever damping beam entity vibration test are set to calculate the composite cantilever beam finite element model. The acceleration-time vibration response curve Complex_CAE_Curve at the position is used to obtain the second vibration acceleration curve.

[0067] Based on the above embodiments, Figure 3As shown, the damping material parameters include a loss factor. Further, any of the material parameters may include a loss factor. The corresponding step S102 of "adjusting the damping material parameters of the finite element model of the test sample during the simulation vibration test of the finite element model of the test sample" includes the following steps:

[0068] S301, determining a first acceleration amplitude corresponding to a target order resonance frequency in the first vibration acceleration curve;

[0069] S302, determining a second acceleration amplitude corresponding to the target order resonance frequency in the second vibration acceleration curve;

[0070] Under the excitation of continuous frequency, the obtained vibration acceleration curve shows that the response acceleration amplitude changes continuously with frequency.

[0071] It is not difficult to understand that resonance refers to the phenomenon that a system vibrates with a large amplitude when it is stimulated by the outside world. The excitation frequency when the vibration amplitude is the largest is called the resonance frequency. Therefore, the excitation frequency when the vibration acceleration amplitude is the largest is the resonance frequency. As the frequency changes, the frequency when the resonance phenomenon occurs for the first time is recorded as the first-order resonance frequency, and the frequency when the resonance phenomenon occurs for the second time is recorded as the second-order resonance frequency.

[0072] After obtaining the first vibration acceleration curve and the second vibration acceleration curve, the present application determines the first acceleration amplitude of the target order resonance frequency in the first vibration acceleration curve and the second acceleration amplitude of the target order resonance frequency in the second vibration acceleration curve. It is not difficult to understand that the frequency values ​​of the resonance frequency of the same order in two different vibration acceleration curves can be the same or different.

[0073] S303, if the second acceleration amplitude is greater than the first acceleration amplitude, increasing the loss factor corresponding to the frequency range where the target order resonance frequency is located under the finite element model of the test sample;

[0074] S304: If the second acceleration amplitude is smaller than the first acceleration amplitude, reducing the loss factor corresponding to the frequency range where the target order resonance frequency is located under the finite element model of the test sample.

[0075] The present application adjusts the magnitude of the loss factor according to the acceleration amplitude of the vibration acceleration curve.

[0076] If the second acceleration amplitude corresponding to the finite element model of the test sample is greater than the first acceleration amplitude corresponding to the test sample, it is considered that the damping material loss factor set in the finite element model of the test sample is too low, and the damping material loss factor needs to be further increased. It should be noted that the numerical adjustment amplitude of the damping material loss factor can be set as needed each time, and this application does not limit it.

[0077] If the second acceleration amplitude corresponding to the finite element model of the test sample is smaller than the first acceleration amplitude corresponding to the test sample, it is considered that the damping material loss factor set in the finite element model of the test sample is too high, and the damping material loss factor needs to be further reduced.

[0078] This application compares the response amplitudes of the test sample and the finite element model of the test sample in the physical vibration test and the simulated vibration test when resonance occurs, and determines whether the finite element model of the test sample can show the same shock absorption effect as the test sample under the effect of the currently set damping material loss factor, thereby providing direction for adjusting the damping material loss factor of the finite element model of the test sample. The final damping material loss factor can characterize the shock absorption effect of the damping material in actual application, and improve the accuracy of the obtained damping material loss factor.

[0079] On the basis of the above embodiment, the above damping material parameters also include elastic modulus. Further, the above arbitrary material parameters may also include elastic modulus. Correspondingly, the elastic modulus may be adjusted as follows while adjusting the loss factor:

[0080] If the frequency value of the target order resonance frequency in the second vibration acceleration curve is less than the frequency value of the target order resonance frequency in the first vibration acceleration curve, the elastic modulus of the finite element model of the test sample is increased; if it is greater than, the elastic modulus of the finite element model of the test sample is decreased.

[0081] If the frequency value of the target order resonance frequency in the second vibration acceleration curve obtained by the simulated vibration test is smaller than the first vibration acceleration curve obtained by the physical vibration test, it can be considered that the value of the elastic modulus in the finite element model of the test sample is too small, and the elastic modulus of the finite element model of the test sample needs to be further increased. On the contrary, if the frequency value of the target order resonance frequency in the second vibration acceleration curve obtained by the simulated vibration test is larger than the first vibration acceleration curve obtained by the physical vibration test, it can be considered that the value of the elastic modulus in the finite element model of the test sample is too small, and the elastic modulus of the finite element model of the test sample needs to be further increased.

[0082] It should be noted that the numerical adjustment range of the elastic modulus of the damping material can be set as needed each time, and this application does not limit it.

[0083] The present application determines whether the finite element model of the test sample can exhibit the same stress-strain performance as the test sample by comparing the response amplitudes of the test sample and the finite element model of the test sample when resonance occurs under the same excitation, thereby providing direction for adjusting the elastic modulus value of the finite element model of the test sample, so that the final value of the elastic modulus of the damping material can characterize the stress-strain performance of the damping material in actual applications, thereby enhancing the accuracy of the obtained elastic modulus.

[0084] In some embodiments, the target order resonance frequency referred to when adjusting the loss factor may be a first-order vibration frequency and / or a second-order vibration frequency in the vibration acceleration curve.

[0085] In some embodiments, the first-order resonance frequency, the second-order resonance frequency, the acceleration amplitude corresponding to the first-order resonance frequency, and the acceleration amplitude corresponding to the second-order resonance frequency in the vibration acceleration curve output by the simulation vibration test and the vibration acceleration curve output by the physical vibration test can be observed at the same time, and the loss factor corresponding to the frequency band where the first-order resonance frequency is located is adjusted according to the difference between the first-order resonance frequency in the two curves, and the loss factor corresponding to the frequency band where the second-order resonance frequency is located is adjusted according to the difference between the second-order resonance frequency in the two curves. The elastic modulus is adjusted according to the difference between the acceleration amplitude corresponding to the first-order resonance frequency and the acceleration amplitude corresponding to the second-order resonance frequency in the two curves.

[0086] For example, Figure 4 As shown in the figure, it is the vibration acceleration curve of the cantilever steel beam in the simulation vibration test and the actual vibration test. Figure 4 The horizontal axis of the coordinate system represents frequency (unit: Hz), and the vertical axis of the coordinate system represents acceleration (unit: mm / s 2 ). CAE_Opt1~8 are the vibration acceleration curves of the simulation output after each material parameter adjustment.

[0087] The acceleration vibration response curve "Test_curve" obtained in the cantilever steel beam solid vibration test, and the acceleration vibration response curve "CAE_curve" obtained in the cantilever steel beam finite element model simulation vibration test. Comparing the Test_curve with the curve "CAE_curve" obtained by finite element calculation, it is found that the resonant frequency of the curve obtained by CAE analysis is low. According to the cantilever beam natural frequency calculation formula: This indicates that the elastic modulus E of the steel beam in the finite element model is too low, and the elastic modulus of the steel needs to be increased until the resonant frequency of the curve obtained by CAE analysis is basically consistent with the resonant frequency of the curve obtained by the physical vibration test; secondly, the amplitude of the acceleration vibration response at the first-order resonance frequency is too high, indicating that the low-frequency loss factor of the steel in the finite element model is too low, and the low-frequency loss factor of the steel needs to be increased. The amplitude of the acceleration response at the second-order resonance frequency is too low, indicating that the high-frequency loss factor is too high, and the high-frequency loss factor needs to be reduced. By continuously adjusting the low-frequency and high-frequency damping loss factors in the finite element model, the curve obtained by CAE completely coincides with the curve obtained by the physical vibration test. After several rounds of finite element simulation model parameter adjustment, the output "CAE_curve" is infinitely close to the test curve "Test_curve".

[0088] For example, Figure 5 As shown, the vibration acceleration curve of the composite cantilever damping beam in the simulation vibration test and the physical vibration test. Figure 5 The horizontal axis of the coordinate system represents frequency (unit: Hz), and the vertical axis of the coordinate system represents acceleration (unit: mm / s 2 ).

[0089] From the composite cantilever damping beam original vibration response simulation curve "Complex_CAE_Orig_Curve" curve, it can be seen that the first-order and second-order resonance frequencies of the simulation curve are high, and the response amplitude is high, indicating that in the composite cantilever damping beam finite element model, the elastic modulus of the viscoelastic damping material is designed to be high, and the elastic modulus value needs to be reduced; and the loss factor of the damping material is low, and the loss factor value of the damping material needs to be increased. Through a series of parameter adjustments, the optimized composite cantilever damping beam finite element model is calculated and solved, and finally the "Complex_CAE_Opt_Curve" is infinitely close to the "Complex_Test_Curve" curve. At this time, the elastic modulus E of the viscoelastic damping material in the finite element model is obtained. D and loss factor η D That is, it is equivalent to the mechanical parameters of the viscoelastic damping material in the entity vibration test.

[0090] When judging whether the first vibration acceleration curve matches the second vibration acceleration curve, the following three methods can be used:

[0091] First, when the loss factor and elastic modulus are adjusted with the first-order resonance frequency as a reference, the two vibration acceleration curves can be considered to match when the frequency value corresponding to the first-order resonance frequency and the vibration response amplitude between the two curves have an error within a preset range.

[0092] Secondly, if the loss factor and elastic modulus are adjusted with the second-order resonance frequency as a reference, when the frequency value and vibration response amplitude corresponding to the second-order resonance frequency between the two curves have an error within a preset range, the two vibration acceleration curves can be considered to match.

[0093] Third, preferably, whether the first vibration acceleration curve matches the second vibration acceleration curve can be determined by the following method:

[0094] If the frequency difference corresponding to the first-order resonance frequency between the first vibration acceleration curve and the second vibration acceleration curve is less than the first error threshold, the frequency difference corresponding to the second-order resonance frequency is less than the second error threshold, the acceleration amplitude difference corresponding to the first-order vibration frequency is less than the third error threshold, and the acceleration amplitude difference corresponding to the second-order vibration frequency is less than the fourth error threshold, then it is determined that the first vibration acceleration curve matches the second vibration acceleration curve. In this way, the finite element model of the test sample exhibits the same vibration response as the test sample, so that the damping material parameters finally corresponding to the finite element model can characterize the shock absorption performance of the damping material when it is actually applied to the body panel. Otherwise, it is determined that the first vibration acceleration curve does not match the second vibration acceleration curve.

[0095] In summary, the material parameter acquisition method of the damping material proposed in the present invention combines experimental testing with simulation calculations, and the loss factor value obtained can not only evaluate the vibration reduction performance of the damping material, but can also be directly loaded into the finite element calculation model for damping optimization design, evaluation of vehicle NVH performance and lightweight design. The method proposed in this application takes into account the application environment conditions of the material and can provide an important basis for the selection of damping materials.

[0096] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0097] Figure 6 is a schematic block diagram of a material parameter acquisition device for a viscoelastic damping material according to another exemplary embodiment of the present application. Figure 6 As shown, the device 600 includes an acquisition module 601 , a parameter adjustment module 602 and a parameter determination module 603 .

[0098] An acquisition module 601 is used to acquire material parameters of a substrate in a test sample as the substrate material parameters of a finite element model of the test sample, wherein the test sample is a substrate sample provided with a free damping layer of the viscoelastic damping material;

[0099] A parameter adjustment module 602 is used to adjust the material parameters of the finite element model of the test sample during the process of performing a simulation vibration test on the finite element model of the test sample under a preset analysis condition, until the finite element model of the test sample responds to a second vibration acceleration curve that matches the first vibration acceleration curve, wherein the first vibration acceleration curve is obtained by performing a physical vibration test on the test sample under the preset analysis condition;

[0100] The parameter determination module 603 is used to determine the damping material parameters currently corresponding to the finite element model of the test sample as the material parameters of the viscoelastic damping material.

[0101] In an embodiment of the present application, the material parameters of the substrate are: when a fourth vibration acceleration curve matching the third vibration acceleration curve is obtained during a simulation vibration test of the finite element model of the substrate sample under the preset analysis conditions, the material parameters of the finite element model of the substrate sample, and the third vibration acceleration curve is obtained by performing a physical vibration test on the substrate sample under the preset analysis conditions.

[0102] In an embodiment of the present application, the damping material parameters include a loss factor, and the parameter adjustment module is used to: determine a first acceleration amplitude corresponding to a target order resonance frequency in the first vibration acceleration curve; determine a second acceleration amplitude corresponding to the target order resonance frequency in the second vibration acceleration curve; if the second acceleration amplitude is greater than the first acceleration amplitude, increase the loss factor corresponding to the frequency range where the target order resonance frequency is located under the finite element model of the test sample; if the second acceleration amplitude is less than the first acceleration amplitude, decrease the loss factor corresponding to the frequency range where the target order resonance frequency is located under the finite element model of the test sample.

[0103] In an embodiment of the present application, the damping material parameters also include an elastic modulus; the parameter adjustment module is used to: if the frequency value of the target order resonance frequency in the second vibration acceleration curve is less than the frequency value of the target order resonance frequency in the first vibration acceleration curve, then increase the elastic modulus of the finite element model of the test sample; if the frequency value of the target order resonance frequency in the second vibration acceleration curve is greater than the frequency value of the target order resonance frequency in the first vibration acceleration curve, then decrease the elastic modulus of the finite element model of the test sample.

[0104] In the embodiment of the present application, the target order resonance frequency is a first order resonance frequency and / or a second order resonance frequency.

[0105] In an embodiment of the present application, whether the first vibration acceleration curve matches the second vibration acceleration curve is determined in the following manner: if the frequency difference corresponding to the first-order resonance frequency between the first vibration acceleration curve and the second vibration acceleration curve is less than the first error threshold, the frequency difference corresponding to the second-order resonance frequency is less than the second error threshold, the acceleration amplitude difference corresponding to the first-order vibration frequency is less than the third error threshold, and the acceleration amplitude difference corresponding to the second-order vibration frequency is less than the fourth error threshold, then it is determined that the first vibration acceleration curve matches the second vibration acceleration curve.

[0106] In the embodiment of the present application, the test sample is the composite cantilever damping beam, and the substrate sample is a cantilever steel beam.

[0107] In an embodiment of the present application, the preset analysis condition includes applying an exciting force with a continuously changing frequency to a preset force application point of the sample, and collecting the vibration acceleration of the sample at a preset collection point.

[0108] In summary, the present application proposes a material parameter acquisition device for a viscoelastic damping material, which first acquires the material parameters of the substrate in the test sample, so as to fix the substrate material parameters of the finite element model of the test sample as the material parameters of the substrate in the test sample, thereby setting the substrate material parameters with higher accuracy for the finite element model of the test sample, avoiding the influence of the error of the substrate material parameters on the vibration response of the simulated vibration test, and in addition, under the same preset analysis conditions, the first vibration acceleration curve output by the physical vibration test and the second vibration acceleration curve output by the simulated vibration test are acquired, so that the variables between the simulated vibration test and the physical vibration test can be controlled to the maximum extent on the damping material parameters, so that the damping material parameters finally obtained can better adapt to the response curve of the physical vibration test. Then, by adjusting the damping material parameters of the finite element model of the test sample, the second vibration acceleration curve output by the simulated vibration test of the finite element model of the test sample is adjusted, until a second vibration acceleration curve matching the first vibration acceleration curve is obtained, and the damping material parameters of the finite element model of the test sample at this time are determined as the material parameters of the viscoelastic damping material. The present application uses the response of the physical vibration test as a reference to adjust the damping material parameters of the simulated vibration test, so that the finite element model of the test sample can exhibit the same vibration response as the physical vibration test of the test sample based on the final determined damping material parameters and substrate material parameters. The final damping material parameters are used as the material parameters of the viscoelastic damping material, so that when designing the damping distribution and NVH performance of the vehicle, the material parameters of the referenced viscoelastic damping material can effectively represent the stress-strain performance of the damping material when it is actually applied to the body sheet metal, providing accurate basic data for the subsequent application of the damping material.

[0109] In order to implement the above embodiment, the present application embodiment also proposes an electronic device 700, such as Figure 7 As shown, the electronic device 700 may specifically include: a memory 701, a processor 702, and a computer program stored in the memory 701 and executable on the processor 702. When the processor 702 executes the program, the steps of the material parameter acquisition method of the viscoelastic damping material shown in the above embodiment are implemented.

[0110] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0111] Those skilled in the art can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example. In actual applications, the above-mentioned functions can be distributed and completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above.

[0112] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A method for obtaining material parameters of a viscoelastic damping material, It is characterized in that include: Obtaining material parameters of a substrate in a test sample as substrate material parameters of a finite element model of the test sample, wherein the test sample is a substrate sample provided with a free damping layer of the viscoelastic damping material; During the process of performing a simulated vibration test on the finite element model of the test sample under the preset analysis conditions, adjusting the damping material parameters of the finite element model of the test sample until the finite element model of the test sample responds to a second vibration acceleration curve that matches the first vibration acceleration curve, wherein the first vibration acceleration curve is obtained by performing a physical vibration test on the test sample under the preset analysis conditions; The damping material parameters currently corresponding to the finite element model of the test sample are determined as the material parameters of the viscoelastic damping material.

2. The method according to claim 1, It is characterized in that The material parameters of the substrate are: under the preset analysis conditions, when a fourth vibration acceleration curve matching the third vibration acceleration curve is obtained during a simulation vibration test of the finite element model of the substrate sample, the material parameters of the finite element model of the substrate sample, wherein the third vibration acceleration curve is obtained by performing a physical vibration test on the substrate sample under the preset analysis conditions.

3. The method according to claim 1, It is characterized in that The damping material parameters include a loss factor. During the process of performing a simulation vibration test on the finite element model of the test sample, adjusting the damping material parameters of the finite element model of the test sample includes: Determining a first acceleration amplitude corresponding to a target order resonance frequency in the first vibration acceleration curve; Determining a second acceleration amplitude corresponding to the target order resonance frequency in the second vibration acceleration curve; If the second acceleration amplitude is greater than the first acceleration amplitude, increasing the loss factor corresponding to the frequency range where the target order resonance frequency is located under the finite element model of the test sample; If the second acceleration amplitude is smaller than the first acceleration amplitude, the loss factor corresponding to the frequency range where the target order resonance frequency is located under the finite element model of the test sample is reduced.

4. The method according to claim 3, It is characterized in that The damping material parameters also include elastic modulus; During the process of performing the simulation vibration test on the finite element model of the test sample, adjusting the damping material parameters of the finite element model of the test sample further includes: If the frequency value of the target order resonance frequency in the second vibration acceleration curve is less than the frequency value of the target order resonance frequency in the first vibration acceleration curve, increasing the elastic modulus of the finite element model of the test sample; If the frequency value of the target order resonance frequency in the second vibration acceleration curve is greater than the frequency value of the target order resonance frequency in the first vibration acceleration curve, the elastic modulus of the finite element model of the test sample is reduced.

5. The method according to claim 3 or 4, It is characterized in that The target order resonance frequency is a first order resonance frequency and / or a second order resonance frequency.

6. The method according to claim 1, It is characterized in that Whether the first vibration acceleration curve matches the second vibration acceleration curve is determined in the following manner: If, between the first vibration acceleration curve and the second vibration acceleration curve, the frequency difference corresponding to the first-order resonance frequency is less than the first error threshold, the frequency difference corresponding to the second-order resonance frequency is less than the second error threshold, the acceleration amplitude difference corresponding to the first-order resonance frequency is less than the third error threshold, and the acceleration amplitude difference corresponding to the second-order resonance frequency is less than the fourth error threshold, it is determined that the first vibration acceleration curve matches the second vibration acceleration curve.

7. The method according to claim 1, It is characterized in that The test sample is the composite cantilever damping beam, and the substrate sample is a cantilever steel beam.

8. The method according to claim 1 or 2, It is characterized in that The preset analysis working condition includes applying an exciting force with a continuously changing frequency to a preset force application point of the sample, and collecting the vibration acceleration of the sample at a preset collection point.

9. A material parameter acquisition device for a viscoelastic damping material, It is characterized in that include: An acquisition module, used for acquiring material parameters of a substrate in a test sample as the substrate material parameters of a finite element model of the test sample, wherein the test sample is a substrate sample provided with a free damping layer of the viscoelastic damping material; a parameter adjustment module, used for adjusting the damping material parameters of the finite element model of the test sample during the process of performing a simulated vibration test on the finite element model of the test sample under a preset analysis condition, until the finite element model of the test sample responds to a second vibration acceleration curve that matches the first vibration acceleration curve, wherein the first vibration acceleration curve is obtained by performing a physical vibration test on the test sample under the preset analysis condition; The parameter determination module is used to determine the damping material parameters currently corresponding to the finite element model of the test sample as the material parameters of the viscoelastic damping material.

10. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, It is characterized in that When the processor executes the computer program, the steps of the method for obtaining material parameters of the viscoelastic damping material according to any one of claims 1 to 8 are implemented.

11. A computer-readable storage medium having a computer program stored thereon, It is characterized in that When the program is executed by a processor, the steps of the method for obtaining material parameters of the viscoelastic damping material as described in any one of claims 1 to 8 are implemented.

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