1. The equivalent modeling method for the random vibration simulation by using the vibration damping device with directivity is characterized by comprising the following steps of:

step one, establishing a model of an energy storage support with a vibration damper, and importing mesh division software to divide meshes;

step two, establishing linear connection of each part in the model obtained in the step one;

step three, setting parameters of conventional materials and endowing the model obtained in the step one;

respectively establishing equivalent models for different types of vibration damping devices, and acquiring and setting material parameters of the equivalent models;

step five, loading boundary conditions;

and sixthly, performing modal analysis or frequency response analysis or random vibration analysis, and visually judging whether the strength of each area of the energy storage support meets the requirement or not from the simulation result.

2. The equivalent modeling method for random vibration simulation of the vibration damping device with directivity according to claim 1 is characterized in that in the first step, Pro/Engineer operation software is used for establishing a model of the energy storage bracket with the vibration damping device, and then Hypermesh software is introduced for grid division.

3. The equivalent modeling method for random vibration simulation by using the directional vibration damping device according to claim 1, wherein in the second step, the establishment of the linear connection of the components in the model obtained in the first step comprises:

establishing a BEAM BEAM unit for the bolt connection;

welding to establish weld joint connection;

other fixed connections establish binding contacts.

4. The equivalent modeling method for random vibration simulation using the directional vibration damping device according to claim 1, wherein in step four, the vibration damping device comprises a metal rubber type vibration damping device and a spring damper type vibration damping device; the modeling mode of the metal rubber vibration damper is established in an equivalent mode, equivalent to a homogeneous square, equivalent calculation of the elastic modulus, the Poisson ratio, the rigidity, the density and the damping ratio is carried out, the established equivalent model is endowed, and the damping ratios of corresponding materials are endowed to different materials one by one; the modeling mode of the spring damper type vibration damper device is equivalent modeling by using a spring unit, a coordinate system is required to be established independently during modeling, the upper point and the lower point of the spring are ensured to be located at the same coordinate, and then the spring unit is endowed with a rigidity property and a damping property to complete equivalence.

5. The equivalent modeling method for random vibration simulation of a vibration damping device with directivity according to claim 1, characterized in that in step five, the boundary condition loading includes the steps of:

the equivalent model is well established, and the external loading condition of the equivalent model is, for example, the loaded PSD power spectral density.

Background

Along with the rapid development of the energy storage industry, the application of energy storage equipment is more and more extensive, and the original energy storage product is applied to fixed position more, only needs to satisfy the static strength requirement to the structural strength design requirement of energy storage product. At present, along with the development of energy storage products, vehicle-mounted energy storage products are also popular gradually, and because of the heavy weight and the high size of the vehicle-mounted energy storage products, the products are easy to resonate in the vehicle-mounted application process to damage structural members such as brackets, and a vibration damping device is required to be introduced to absorb resonance energy to reduce the strength load of the structural members such as brackets. In the existing random vibration simulation method, a good equivalent modeling method aiming at the vibration damper is not provided for a moment to accurately evaluate whether a product added with the vibration damper meets the strength requirement in the transportation process, and the invention aims to make up for the blank.

Disclosure of Invention

In order to solve the problems in the prior art, the invention aims to provide an equivalent modeling method for random vibration simulation by using a directional vibration damping device.

In order to achieve the purpose and achieve the technical effect, the invention adopts the technical scheme that:

an equivalent modeling method for a vibration damping device with directivity used for random vibration simulation comprises the following steps:

step one, establishing a model of an energy storage support with a vibration damper, and importing mesh division software to divide meshes;

step two, establishing linear connection of each part in the model obtained in the step one;

step three, setting parameters of conventional materials and endowing the model obtained in the step one;

respectively establishing equivalent models for different types of vibration damping devices, and acquiring and setting material parameters of the equivalent models;

step five, loading boundary conditions;

and sixthly, performing modal analysis or frequency response analysis or random vibration analysis, and visually judging whether the strength of each area of the energy storage support meets the requirement or not from the simulation result.

Further, in the step one, Pro/Engineer operation software is used for establishing a model of the energy storage support with the vibration damper, and then Hypermesh software is introduced for grid division.

Further, in step two, the establishing of the linear connection of each component in the model obtained in step one includes:

establishing a BEAM BEAM unit for the bolt connection;

welding to establish weld joint connection;

other fixed connections establish binding contacts.

Further, in the fourth step, the vibration damper includes a metal rubber vibration damper and a spring damper vibration damper; the modeling mode of the metal rubber vibration damper is established in an equivalent mode, equivalent to a homogeneous square, equivalent calculation of the elastic modulus, the Poisson ratio, the rigidity, the density and the damping ratio is carried out, the established equivalent model is endowed, and the damping ratios of corresponding materials are endowed to different materials one by one; the modeling mode of the spring damper type vibration damper device is equivalent modeling by using a spring unit, a coordinate system is required to be established independently during modeling, the upper point and the lower point of the spring are ensured to be located at the same coordinate, and then the spring unit is endowed with a rigidity property and a damping property to complete equivalence.

Further, in step five, the loading of the boundary condition includes the following steps:

the equivalent model is well established, and the external loading condition of the equivalent model such as bearing twice gravity is that the PSD power spectral density is loaded.

Compared with the prior art, the invention has the beneficial effects that:

the invention discloses an equivalent modeling method for a vibration damper with directivity for random vibration simulation, which comprises the following steps: step one, establishing a model of an energy storage support with a vibration damper, and importing mesh division software to divide meshes; step two, establishing linear connection of each part in the model obtained in the step one; step three, setting parameters of conventional materials and endowing the model obtained in the step one; respectively establishing equivalent models for different types of vibration damping devices, and acquiring and setting material parameters of the equivalent models; step five, loading boundary conditions; and sixthly, performing modal analysis or frequency response analysis or random vibration analysis, and evaluating the reliability of the vibration damper. The equivalent modeling method for the vibration damper with directivity for the random vibration simulation effectively utilizes the simulation means to evaluate the rationality of the type selection of the vibration damper, the simplified vibration damper can be directly used for the random vibration simulation of the vehicle-mounted energy storage system, and whether the strength of each area of the structural member of the energy storage device meets the requirement can be visually judged from the simulation result.

Drawings

FIG. 1 is a flow chart of the present invention;

fig. 2 is a cloud of the results of random oscillations of example 1 of the present invention.

Detailed Description

The present invention is described in detail below with reference to the attached drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby clearly defining the protection scope of the present invention.

The following presents a simplified summary of one or more aspects in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects, and is intended to neither identify key or critical elements of all aspects nor delineate the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later.

Example 1

As shown in fig. 1-2, an equivalent modeling method of a vibration damping device with directivity for random vibration simulation includes the following steps:

step one, establishing a model of an energy storage support with a vibration damper, and importing mesh division software to divide meshes;

step two, establishing linear connection of each part in the model obtained in the step one;

step three, setting parameters of conventional materials and endowing the model obtained in the step one; the conventional material parameters comprise elastic modulus, Poisson's ratio, density and damping ratio, and the set principle is that the parameters are measured by the parameter test of the material and then input into simulation software; the design step three is based on the starting point that materials of all parts of the energy storage support are different, unit types are also different, so that corresponding material attributes of all the parts need to be given to improve the simulation precision, the material attributes are obtained through calculation of a formula I to a formula IV below, and then corresponding parameters are set through simulation software;

respectively establishing equivalent models for different types of vibration damping devices, and acquiring and setting material parameters of the equivalent models;

step five, loading boundary conditions;

and sixthly, performing modal analysis or frequency response analysis or random vibration analysis, and visually judging whether the strength of each area of the energy storage support meets the requirement or not from the simulation result.

In the first step, Pro/Engineer operation software or other three-dimensional design software is used for establishing a model of the energy storage bracket with the vibration damper, after the model is established, a simulation model is established, Hypermesh software or other mesh division software is introduced for dividing meshes, and after the meshes are divided, connection processing is carried out, namely, the second step is carried out.

In the second step, the establishment of the linear connection of each part in the model obtained in the first step comprises the following steps:

establishing a BEAM BEAM unit for the bolt connection;

welding to establish weld joint connection;

other fixed connections establish binding contacts, etc.

In the fourth step, the vibration damper comprises a metal rubber vibration damper and a spring damper vibration damper; the modeling mode of the metal rubber vibration damper is established in an equivalent mode, equivalent to a homogeneous square, the elastic modulus, the Poisson ratio, the rigidity, the density and the damping ratio are calculated equivalently, the established equivalent model is endowed, other parts are respectively and correspondingly endowed with corresponding materials to replace the original simulation mode to give the model an integral damping ratio method for calculation, it needs to be explained that the common mode in the prior art is to give an integral structure damping to the integral model, the method abandons the method, and the damping ratios of the corresponding materials are required to be endowed to different materials one by one, so that the vibration damping effect brought by the vibration damper (including a vibration pad) can be known, but not an integral value is given systematically; the modeling mode of the spring damper type vibration damper device is equivalent modeling by using a spring unit, a coordinate system is required to be established independently during modeling, the upper point and the lower point of a spring are ensured to be located at the same coordinate, and then the spring unit is endowed with a rigidity property and a damping property to complete equivalence. It should be noted that the spring unit is a CBUSH unit, which is generally used only for spring components, and because the spring unit and the damper have some similar properties (stiffness and damping), the damper is characterized by the spring unit, which is a part consisting of many components, and if a simulation model is established, it takes time and labor, and is not necessary, so the invention designs the equivalent method for the first time, and then calculates the parameters of the damper to the spring unit, and the spring unit itself is a simple unit, which can be directly established in software, is simple and fast, and is equivalent to a connector, which connects two components, and the spring unit replaces the damper, and where the damper is, the spring unit is replaced by the spring unit.

For the metal rubber type vibration damper, the hardness HA of the metal rubber type vibration damper is represented by testing the elastic dent of the rubber, and then the elastic modulus E is calculated by using a formula I:

the vibration of the vibration absorber in the metal rubber vibration absorber is regarded as single-degree-of-freedom forced vibration under simple harmonic excitation, and the system transfer rate beta is calculated by a formula II:

where λ is the frequency ratio and ζ is the damping ratio.

And obtaining a derivative of the formula two to obtain an extreme value to obtain a formula three:

system transmissibility beta through vibrationAnd dynamic sweep frequency test is carried out, and the test is carried out by using sine sweep frequency experiments excited by different acceleration. In addition, the metal rubber type vibration damper is used for unidirectional vibration damping, and in order to improve the precision, the elasticity modulus of other directions except the vibration direction is given to the conventional parameter 2000MP_aSince there is no lateral deformation during deformation under pressure, the poisson ratio is set to 0.

For the spring damper type damping device, a force-displacement curve can be obtained by performing a compression test on the damping device, the spring damper type damping device meets Hooke's law, and the rigidity K can be calculated according to the Hooke's law.

The resonance magnification eta is calculated according to the formula four:

as is understood from the vibration theory, when the frequency ratio λ is 1, resonance occurs, and at this time, the resonance amplification factor is maximized and needs to be smaller than the design value, whereby the damping ratio ζ can be calculated. In the model, the stiffness K in the other direction than the vibration direction is set to a fixed value rigid, and only the damping ratio ζ in the vibration direction needs to be set.

After the damping ratio is calculated, equivalent vibration damping related parameters of the vibration damping device model can be given.

In the fifth step, the boundary condition loading comprises the following steps:

the equivalent model is well established, and the external loading condition of the equivalent model is, for example, the loaded PSD power spectral density.

The present embodiment is explained by taking random vibration simulation as an example, firstly, how much stress each position in the model is subjected to needs to be calculated through simulation, and then refer to 3_σAnd judging according to a criterion, namely multiplying the stress value of each position of the model by 3 times, and comparing with the material yield strength of the position corresponding to the model, wherein if the stress value is less than the yield strength, the requirement is met, and if the stress value is more than the yield strength, the fracture risk exists.

Fig. 2 is a cloud chart of the result of random vibration, and it can be known from fig. 2 that:

1) multiplier-3.0, representing 3 σ stress, showing that the results have been multiplied by a factor of 3;

2) the maximum value 337.6Mpa shown in fig. 2 is the maximum position of the random vibration stress of the model, the position i in fig. 2 is the corresponding position of the maximum stress, the stress of each position in the model is calculated by finite element theoretical simulation software, the accurate stress value of any position can be accurately seen, the approximate stress range is judged according to the color, the stress of the model is mainly in the range from yellow to blue 4, the colors represented by blue 1, blue 2, blue 3 and blue 4 are gradually deepened, and the represented stress value is gradually reduced;

3) and (4) judging the standard: the steel used at the position with the maximum stress of the model is an HC340 material, the yield strength corresponding to the material is 340MPa, the maximum 3 sigma stress of the model is 337.6MPa < 340MPa, namely the strength design requirement is met, if the maximum 3 sigma stress is greater than the yield strength of the material, the fracture risk exists, the comparison of other areas is similar, and the description is omitted here.

The parts of the invention not specifically described can be realized by adopting the prior art, and the details are not described herein.

The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by the present specification, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.