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Transient non-linear dynamic analysis of automotive disc brake squeal – On the need to consider both stability and non-linear analysis

J.-J. Sinou
2010 Mechanics research communications  
(for the detection and prediction of instabilities) and the time analysis (for the characterization of the non-linear dynamic behavior in time domain)  ...  It will be illustrated that only considering the stability analysis around an equilibrium point is not sufficient for predicting the possible number of unstable modes (i.e. the fundamental frequency components  ... 
doi:10.1016/j.mechrescom.2009.09.002 fatcat:l3p3f6lmovbdxgkjwqbznso5zi

Investigation of the Machining Stability of a Milling Machine with Hybrid Guideway Systems

Jui-Pin Hung, Wei-Zhu Lin, Yong-Jun Chen, Tzou-Lung Luo
2016 Applied Sciences  
The critical cutting depth predicted at the vibration mode associated with the machine tool structure is about 10 mm and 25 mm in the X and Y direction, respectively, while the cutting depth predicted  ...  Also, the machining stability can be increased when the preload of linear roller guides of the feeding mechanism is changed from lower to higher amount.  ...  Acknowledgments: We gratefully acknowledge the support for this work provided by National Science Council in Taiwan through project number MOST103-2221-E-167-004.  ... 
doi:10.3390/app6030076 fatcat:qxr6wa7wrfarnoamnszlz6urbm

Nonlinear development and secondary instability of traveling crossflow vortices

Fei Li, Meelan M. Choudhari, Lian Duan, Chau-Lyan Chang
2014 Physics of Fluids  
The linear growth predictions based on the secondary instability theory are found to agree well with both parabolized stability equations and direct numerical simulation, and the most significant discrepancies  ...  breakdown mechanisms associated with stationary crossflow instability over a swept-wing configuration, this paper investigates the secondary instability of traveling crossflow modes as an alternate scenario for  ...  Figure 12 shows the amplitude curves for the fundamental frequency of the 13.5 kHz Y/Z mode.  ... 
doi:10.1063/1.4883256 fatcat:jv3z2hcxfve5fl7hkjnbsufb5y

Noise and vibration for a self-excited mechanical system with friction

K. Soobbarayen, S. Besset, J-.J. Sinou
2013 Applied Acoustics  
For one and two unstable modes, non-linear time integrations and spectrum analysis are performed to detect all the harmonic components in the velocity spectrum.  ...  In near field, directivity patterns for both cases are composed of four main lobes with different orientations.  ...  The fundamental frequency f 1 detected is the same as the frequency predicted by the stability analysis.  ... 
doi:10.1016/j.apacoust.2013.03.008 fatcat:ltqelef4wbbdzallkqoxylibdi

An architectural understanding of natural sway frequencies in trees

T. Jackson, A. Shenkin, J. Moore, A. Bunce, T. van Emmerik, B. Kane, D. Burcham, K. James, J. Selker, K. Calders, N. Origo, M. Disney (+9 others)
2019 Journal of the Royal Society Interface  
The field data show that a cantilever beam approximation adequately predicts the fundamental frequency of conifers, but not that of broadleaf trees.  ...  These findings demonstrate the value of new three-dimensional measurements for understanding wind impacts on trees and suggest new directions for improving our understanding of tree dynamics from conifer  ...  We used ordinary least-squares linear regression models for all the statistical analysis in this study.  ... 
doi:10.1098/rsif.2019.0116 pmid:31164076 pmcid:PMC6597771 fatcat:v4wuxroebjbv7epz5s7vt4f5j4

Research on EMI Radiation Source Model Based on Battlefield EMC Prediction Analysis

Yong Li, Dong Chen, Xiao Long Zhang
2019 IOP Conference Series: Materials Science and Engineering  
wave emission model, harmonic emission model, non-harmonic emission model, intermodulation interference and intermodulation interference model are constructed for the prediction and analysis of EMI Radiation  ...  Based on the analysis of the characteristics of the transmitter, such as fundamental wave emission, harmonic emission, nonharmonic emission, intermodulation and intermodulation interference, the fundamental  ...  By piecewise linear fitting method, the fundamental modulation envelope is approximated by piecewise linear function.  ... 
doi:10.1088/1757-899x/569/3/032075 fatcat:jwo4fvmt2zck5jmk2vwaz22eei

Modal properties of suspension electricity pylons

Zofia Kozyra, Sławomir Dudziak, V. Andreev
2016 MATEC Web of Conferences  
On this basis, there were proposed formulas to predict the first two natural frequencies for pylons S12P and S24P with good accuracy.  ...  The paper presents the results of the modal analysis of suspension electricity pylons (S12P, S24P, Y52P). The results were obtained from FEM models built in the Abaqus software.  ...  The paper is a result of the SDZP project [System of Dynamic Management of Transmission], which was financially supported by the National Centre for Research and Development and the National Fund for Environmental  ... 
doi:10.1051/matecconf/20168602010 fatcat:mit7x64owbdg5jyhwfb5i4ajae

Comparison of Static and Dynamic Neural Networks for Limit Cycle Oscillation Prediction

Michael R. Johnson, Charles M. Denegri
2003 Journal of Aircraft  
Flight-measured frequency Fiinear Linear flutter analysis Indirect nonlinear Neural network Indirect d, i Free-vibration analysis Direct r Linear flutter analysis Indirect Linear flutter analysis Direct  ...  i, @patural Free-vibration analysis Direct Aw(V) Linear flutter analysis Indirect M Linear flutter analysis, Indirect store carriage configuration, free-vibration modes and frequencies Linear flutter  ... 
doi:10.2514/2.3075 fatcat:f6tdub7n7vgivbvvv3wwgpki5u

Load effect on the vibration characteristics of a stage with rolling guides

Jui Pin Hung
2009 Journal of Mechanical Science and Technology  
The author would like to thank the anonymous reviewers for their valuable suggestions.  ...  The current analysis in the literature of this field predicts a similar trend in the sequence of vibration frequency [2] [3] [4] [5] .  ...  The main peaks of each spectrum can be identified as the natural frequency corresponding to the mode shape that was predicted by the finite element analysis.  ... 
doi:10.1007/s12206-008-0925-4 fatcat:44ykihqwbbfafkdk42wynhpghm

Study of the nonlinear stationary dynamic of single and multi-instabilities for disk brake squeal

Jean Jacques Sinou, Nicolas Coudeyras, Samuel Nacivet
2009 International Journal of Vehicle Design  
A finite element model with friction coupling is used to analyze the stability of the brake system and the stationary nonlinear oscillations for squeal noise prediction.  ...  Second, a brief review of the stability analysis and squeal prediction are given.  ...  Results for a node of the pad (in the X,Y and Z directions) are plotted in Figure 7 : the fundamental frequency that corresponds to the unstable frequency of the mode around 1512Hz (as previously showed  ... 
doi:10.1504/ijvd.2009.027122 fatcat:zkzqf76tu5fyjcfanpidujyulq

Analytical and Finite Element Modeling of the Dynamic Characteristics of a Linear Feeding Stage with Different Arrangements of Rolling Guides

Jyh-Cheng Chang, Jui-Pin Hung
2014 Mathematical Problems in Engineering  
In addition, comparisons of the results from the two approaches further indicate that the platform rigidity is an important factor determining the accuracy of the prediction of the vibration frequencies  ...  Results of the modal analysis show that the vibration behaviors of the positioning stage are dominated by the rigidity of the linear components and the platform.  ...  The fundamental vibration frequencies of linear stage predicted from finite element modal analysis are listed in Table 2 , which also compares the differences between the stages with guide span of 200  ... 
doi:10.1155/2014/454156 fatcat:bxbx7kf6gjcg7hn7t2cbddlm4i

The Effects of Temperature on Vortex-pairing Noise in Axisymmetric Subsonic Jets

Hai-Hua Yang, Lin Zhou, Zhen-Hua Wan, De-Jun Sun
2015 Procedia Engineering  
Direct numerical simulation of compressible Navier-Stokes equations is performed for an accurate description of near-field flow dynamics and far-field sound.  ...  In addition, sound predicted by Lilley-Goldstein acoustic analogy is consistent with the result of simulation in all cases.  ...  Research Funds for the Central Universities.  ... 
doi:10.1016/j.proeng.2015.11.179 fatcat:wqieqd6yencxnhe7ibnekdrwoy

Stability and nonlinear self-excited friction-induced vibrations for a minimal model subjected to multiple coalescence patterns

Mzaki Dakel, Jean-Jacques Sinou
2017 Journal of Vibroengineering  
The numerical study of stability for the static solution of the mechanical system is performed by applying the complex eigenvalue analysis of the linearized differential equations of motion and by identifying  ...  In addition, the presence of the nonlinearity makes necessary the consideration of the nonlinear dynamic analysis in order to explain clearly the complexity of the contribution of different frequency components  ...  Although the linearized stability analysis and the linearization about a static equilibrium point are not valid for the transient dynamic analysis, the major objective of the mentioned comparison is to  ... 
doi:10.21595/jve.2016.17190 fatcat:ypt6zos3pbdrjpbdhvbi7e3zpe

Simulation of Transient Nonlinear Friction-Induced Vibrations Using Complex Interface Modes: Application to the Prediction of Squeal Events

J.-J. Sinou, S. Besset
2017 Shock and Vibration  
Although a nonlinear analysis is more predictive than Complex Eigenvalues Analysis, one of the main drawbacks of the time analysis is the need of large computational efforts.  ...  ., a classical modal reduction via Craig and Bampton plus a condensation at the frictional interface based on complex modes) for the prediction of self-excited vibrations of brake squeal is discussed.  ...  It can be noted that the values of the fundamental frequency calculated from the reference model and the reduced system for the transient time analysis are very close (as shown in Table 2 for = 0.5 and  ... 
doi:10.1155/2017/6107251 fatcat:j4j5srd24rfitlp7mzqtzpjk6y

A Research Study on Vibrating Elements and Consuming Electricity in Predictive Maintenance

Salih Seçkin Erol
2016 European Journal of Interdisciplinary Studies  
The purpose of this research is testing condition monitoring of mechanical looseness failure and resonance for studying comparison of different predictive maintenance perspectives.  ...  According to the analysis results, inspecting of mechanical looseness failure and resonance problem has been detected as the most effectively by vibration analysis.  ...  Some techniques are developed in maintenance diagnosis for linear systems which can be transferred to non-linear systems as well [3] .  ... 
doi:10.26417/ejis.v5i1.p45-50 fatcat:nrdqnjissfd5jao5sfc7zlr75q
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