Abstract:The phenomenon of resonance occurs in rotating shafts and under lies the definition of an often undesirable property: large amplitude motion (whirling)associated with a critical speed. The ability to predict this behavior is notoriously difficult based on conventional modeling approaches, especially so since in the field, it is very likely that conditions change over time. Condition monitoring has developed over the years in order to assess deterioration in a structure or machine in an on-line sense.The approach developed here uses a relatively simple technique to provide a predictive in-situ capability based on measured data. The approach is shown to work well in a variety of situations.
Bio:
Lawrie Virgin is Professor of Mechanical Engineering and Materials Science at Duke University in North Carolina. He is a former Chair of the Department of Civil and Environmental Engineering and has been a faculty member at Duke since 1988.Prior to that he received his education in the United Kingdom culminating in a PhD from the University of London (UCL). His research interests are centered on non linear mechanics especially buckling, nonlinear vibration and their interaction. A good deal of this research has an experimental nature, and the characterization of chaos has been a recurrent theme. Applications of his research include ship capsize, aeroelasticity, marine risers, rotor dynamics, rocking blocks, vibration isolation, impacting systems, sonic fatigue, solar sails and the dynamics of very slender structures. He is the subject editor for Nonlinear Dynamics for Journal of Sound and Vibration. He has written well over a one hundred and forty journal papers and two books: “Introduction to Experimental Nonlinear Dynamics” (2000) and “Vibration of Axially Loaded Structures” (2007) both published by Cambridge University Press.
