ASME 1999
CALL for PAPERS
Symposium on
NONLINEAR RESPONSE OF HYSTERETIC OSCILLATORS
17th Biennal Conference on Mechanical Vibration and Noise
September 12-15,1999
Las Vegas, Nevada
The dynamical behavior of hysteretic systems has received less attention in the past than that of nonlinear elastic systems; however, the situation is changing and the appearance of theoretical and experimental papers on this subject has recently become more frequent. This could be explained by the fact that many systems are known to possess dissipative characteristics independent of velocity, as well as memory-dependent nonlinearities. Most structural elements exhibit hysteretic behavior; to the already large class of materials subjected to large strains, we must now add those materials characterized by phase transition during the response, such as shape memory alloys and ferromagnetic materials.
Therefore many researchers and engineers feel the need for a greater understanding of dynamic response of hysteretic systems under periodic and non-periodic excitations. To this end the present mini-symposium aims to cover various aspects of hysteretic oscillators, including among others the following:
Experimental responses and numerical simulations Critical examination of results and classification of the types of motion found. Studies of one and multi-degree of freedom oscillators under periodic and non-periodic excitations. Comparisons with nonlinear elastic systems.
Modeling of hysteretic rules Modeling rules suitable for direct used in dynamic packages are preferred. Analysis of the different existing models, degrading and not, time-invariant or not, Regularization criteria should be proposed, including thermodynamic stability.
Numerical and semi-analytical methods A step-by-step numerical integration can give trouble when accurate results are required; ad hoc numerical integration schemes are needed. A specific approach to the evaluation of periodic and, more generally, asymptotic response could be useful.
Geometric aspects The lack of smoothness in the dynamic response of hysteretic systems causes difficulties. Concepts such as phase space and invariant manifolds, should be stated according to the theory for nonlinear classical systems.
Interested authors are requested to submit one-page abstract to the organizer (by mail fax, or email) . All papers will be reviewed and, if accepted, will be published in the CD-ROM proceedings of the conference. The important dates and deadlines are: