Abstract for the Tenth conference on
NON-LINEAR VIBRATIONS, STABILITY, DYNAMICS OF STRUCTURES: Identification of non-linear systems
IDENTIFICATION OF THE NON-LINEAR HYSTERETIC BEHAVIOUR
OF A BELT TENSIONERG. MICHON**, L. MANIN*, A. AL MAJID*,R. DUFOUR*
* Laboratoire de Dynamique des Machines et des Structures, UMR CNRS 5006, INSA de Lyon, Bât. Jean d’Alembert, 8 rue des Sciences, 69 621 Villeurbanne, France.
** Valeo Electrical Systems, 2 rue A. Boulle, 94 000 Créteil, France. Corresponding author : Guilhem Michon guilhem.michon@insa-lyon.fr
Tel : + 33 4 72 43 85 87, Fax : + 33 4 72 43 89 30
KEY WORDS: Belt, tensioner, dry friction, hysteresis, non-linear dynamics. ABSTRACT:
Mechanical tensioners are widely used in belt drive systems of automotive engines [1], [2]. They act to maintain a minimum tension in the slack span and to decrease transverse belt vibrations. They are composed of an idler pulley, an arm lever and a torsional spring, see Figure 1.
Figure 1: Sketch of the tensioner T T Spring + Friction Belt Idler Arm lever
The paper deals with the modeling of the dynamic behaviour of a tensioner. First an experimental investigation permits the characterisation of the tensioner: it is subjected to a force-deflection test carried out using a specific experimental set-up equipped with an electro-dynamic shaker. Figure 2 exhibits the non-linear hysteretic behaviour of the tested tensioner. The hysteretic loops are measured for several deflection amplitudes and forcing frequencies.
Then, the experimental characterization permits identifying the parameters required by the original hysteretic model presented in [3], and classical models like the Dahl’s model.
The last part is devoted to the comparison of the hysteretic loops given by the tested models and the experiment, as shown in Figure 2 for low frequency excitation.
Figure 2: Comparison between model and experimental results
ACKNOWLEDGEMENTS:
Authors would like to thank Valeo Electrical Systems for its support in this research program. REFERENCES:
[1] Leamy, Perkins, Nonlinear Periodic Response of Engine Accessory Drives With Dry Friction Tensioners, Journal of Vibration and Acoustics, 1998, Vol. 120, pp 909-916.
[2] Kraver, Fan, Shah, Complex Modal Analysis of a flat Belt Pulley System With Belt Damping and Coulomb-Damped Tensioner, Journal of Mechanical Design, 1996, Vol. 118 pp. 306-311. [3] Al Majid, Dufour, Harmonic Response of a Structure Mounted on an Isolator Modelled with a Hysteretic Operator: Experiments and Prediction, Journal of Sound and Vibration, In Press.
