Non-Linear Generalized Maxwell Model for Dynamic Characterization of Viscoelastic Components and Parametric Identification Techniques

Viscoelastic components are incorporated into automobile and aerospace structures system in order to damp mechanical vibrations. Viscoelastic components are a key element in designing desired dynamic behaviour of mechanical systems. Viscoelastic components dynamic characteristics are often very complex, due to the dependence of its response on several variables, such as frequency, amplitude, preload, and temperature. These dependencies can be critical in capturing the mechanical proprieties and so non linear dynamical behaviour may appear. Assuming that non linearities are due to non linear elasticity, the non linear Generalized Maxwell Model (GMM) is proposed to characterize dynamics of viscoelastic components. Parameters of GMM are identified from Dynamic Mechanical Analysis (DMA) tests for different excitation frequencies. A particular result from identification is that the non linear stiffness is dependent upon displacement amplitude and static displacement under static preload. The significance of this result is that the non linear dynamics of the viscoelastic component can be represented by a simple analytical model capable to produce accurate results. Comparison between measurements and simulations of dynamic stiffness of viscoelastic component has been carried on.

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EXPERIMENTAL CHARACTERIZATION, MODELING AND PARAMETRIC IDENTIFICATION OF THE HYSTERETIC FRICTION BEHAVIOR OF VISCOELASTIC JOINTS

International Journal of Applied Mechanics ◽

10.1142/s175882511350018x ◽

2013 ◽

Vol 05 (02) ◽

pp. 1350018 ◽

Cited By ~ 13

Author(s):

HANEN JRAD ◽

FRANCK RENAUD ◽

JEAN LUC DION ◽

IMAD TAWFIQ ◽

MOHAMED HADDAR

Keyword(s):

Maxwell Model ◽

Parametric Identification ◽

Mechanical Analysis ◽

Friction Model ◽

Structural Vibrations ◽

Friction Behavior ◽

Proposed Model ◽

Essential Components ◽

Generalized Maxwell Model ◽

Dahl Friction Model

Viscoelastic joints connecting solids are essential components of mechanical systems. Viscoelastic components have inherent damping in their structure. Moreover, energy losses in structural vibrations are strongly linked to the friction properties of joints. In this work, a new visco-tribological model was developed by coupling the rheological linear generalized Maxwell model and Dahl friction model. A method for parametric identification is proposed. Parameters of the model are identified from dynamic mechanical analysis (DMA) tests for different excitation frequencies. Comparison between measurements and simulations is performed and the validity of the proposed model is discussed.

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Viscoelasticity Measurement and Identification of Viscoelastic Parametric Models

Volume 1: 23rd Biennial Conference on Mechanical Vibration and Noise, Parts A and B ◽

10.1115/detc2011-47545 ◽

2011 ◽

Cited By ~ 2

Author(s):

Franck Renaud ◽

Gael Chevallier ◽

Jean-Luc Dion ◽

Re´mi Lemaire

Keyword(s):

Complex Function ◽

Shear Stiffness ◽

Maxwell Model ◽

Mechanical Analysis ◽

Parametric Models ◽

Dynamical Mechanical Analysis ◽

Identification Method ◽

Generalized Maxwell Model ◽

Classical Models

Generally speaking, the behaviour of viscoelastic material is more complicated than the behaviour proposed by classical models as Voigt, Maxwell or Zener. The stiffness of such materials is a frequency dependent complex function. Above 1000Hz, classical measurements techniques are unable to achieve accurate measurements of the stiffness. In this paper, a new Dynamical Mechanical Analysis (DMA) tester is presented. It allows the characterization of the shear stiffness of preloaded viscoelastic materials between 200 and 3500Hz and without using frequency-temperature equivalences. Then the Generalized Maxwell model is used to describe behaviours measured with the DMA tester. A new iterative identification method of the parameter of the Generalized Maxwell model is described. This identification method is based on the asymptotes of the model.

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Erratum: “Rheological Equations of Generalized Maxwell Model and Voigt Model in Three-Dimensional, Non-Linear Deformation”

Journal of the Physical Society of Japan ◽

10.1143/jpsj.16.845a ◽

1961 ◽

Vol 16 (4) ◽

pp. 845A-845A

Author(s):

Wataru Segawa

Keyword(s):

Three Dimensional ◽

Maxwell Model ◽

Linear Deformation ◽

Generalized Maxwell Model ◽

Non Linear ◽

Voigt Model

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Rheological Equations of Generalized Maxwell Model and Voigt Model in Three-Dimensional, Non-Linear Deformation.

Journal of the Physical Society of Japan ◽

10.1143/jpsj.16.320 ◽

1961 ◽

Vol 16 (2) ◽

pp. 320-323 ◽

Cited By ~ 1

Author(s):

Wataru Segawa

Keyword(s):

Three Dimensional ◽

Maxwell Model ◽

Linear Deformation ◽

Generalized Maxwell Model ◽

Non Linear ◽

Voigt Model

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Non-Parametric Identification of Asymmetric Signals and Characterization of a Class of Non-Linear Systems Based on Frequency Modulation

Volume 4B: Dynamics, Vibration, and Control ◽

10.1115/imece2016-65229 ◽

2016 ◽

Cited By ~ 3

Author(s):

Václav Ondra ◽

Ibrahim A. Sever ◽

Christoph W. Schwingshackl

Keyword(s):

Linear Systems ◽

Hilbert Transform ◽

Frequency Modulation ◽

Parametric Identification ◽

Free Decay ◽

Non Linear ◽

Non Linear Systems ◽

The Hilbert Transform ◽

Non Parametric

Non-parametric and parametric identification of a non-linear system is often performed by estimating instantaneous amplitude and frequency using the Hilbert transform. However, the Hilbert transform cannot be used for the accurate analysis of asymmetric signals and the reliable estimation of intra-wave frequency modulation. This paper proposes two alternatives to the Hilbert transform which not only avoid some of its mathematical and numerical issues, but also allow the above mentioned analyses. The first method, based on zero-crossing, allows the backbone and damping curves as well as the elastic and damping force characteristics of an asymmetric free decay to be identified. The application and accuracy of this method are demonstrated on the free decay of the system with off-centre clearance. The second method, based on direct quadrature, estimates intrawave frequency modulation frequency with sufficient resolution for characterization of non-linear systems which have stiffness non-linearities. The use of this method is shown on a system with cubic hardening stiffness.

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Experimental Study on Dynamic Properties of a Recycled Composite Sleeper and Its Theoretical Model

Symmetry ◽

10.3390/sym13010017 ◽

2020 ◽

Vol 13 (1) ◽

pp. 17

Author(s):

Zhenhang Zhao ◽

Ying Gao ◽

Chenghui Li

Keyword(s):

Complex Modulus ◽

Dynamic Properties ◽

Low Frequency ◽

Maxwell Model ◽

Theoretical Models ◽

Mechanical Analysis ◽

Factors Affecting ◽

Track System ◽

Generalized Maxwell Model ◽

Temperature Superposition

As a symmetrical structure in track system, the dynamic properties of recycled composite sleepers are important factors affecting the vibration characteristics of track structure. To study the viscoelastic dynamic properties of the composite sleeper, dynamic mechanical analysis (DMA) tests of a composite sleeper at −5 to 30 °C and 1–60 Hz were first carried out, and then the time-temperature superposition (TTS) and the Williams–Landel–Ferry (WLF) formula were used to predict the dynamic properties of a composite sleeper at a wider frequency range. Finally, the generalized Maxwell model was adopted to characterize the dynamic properties of the composite sleeper, which provides parameters and theoretical models for dynamic analysis. The research results show that the composite sleeper has obvious viscoelasticity. Its modulus is large at low temperature or high frequency. On the contrary, the modulus is small at high temperature or low frequency. Under the test conditions, its complex modulus ranges from 1500 to 2700 MPa. The loss factor is in the range of 0.08–0.13. Using the generalized Maxwell model (n = 4), which can better reflect the dynamic properties of the composite sleeper.

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Light-cured dental composites characterization by Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100175272 ◽

1990 ◽

Vol 48 (4) ◽

pp. 428-429

Author(s):

B. M. Culbertson ◽

M. L. Devinev ◽

E. C. Kao

Keyword(s):

Electron Microscopy ◽

Mechanical Analysis ◽

Service Performance ◽

Dental Composite ◽

Dental Composites ◽

Neat Resin ◽

Scanning Calorimetry ◽

Research Meeting ◽

Formulation Variables

The service performance of current dental composite materials, such as anterior and posterior restoratives and/or veneer cements, needs to be improved. As part of a comprehensive effort to find ways to improve such materials, we have launched a broad spectrum study of the physicochemical and mechanical properties of photopolymerizable or visible light cured (VLC) dental composites. The commercially available VLC materials being studied are shown in Table 1. A generic or neat resin VLC system is also being characterized by SEM and TEM, to more fully understand formulation variables and their effects on properties.At a recent dental research meeting, we reported on the differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) characterization of the materials in Table 1. It was shown by DSC and DMA that the materials are substantially undercured by commonly used VLC techniques. Post curing in an oral cavity or a dry environment at 37 to 50°C for 7 or more hours substantially enhances the cure of the materials.

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