A Multiple Whirls Phenomenon and Heuristic Problems in Rotor-Bearing Systems

  • J. KicińskiEmail author
Conference paper
Part of the IUTAM Bookseries book series (IUTAMBOOK, volume 1011)


The results of investigations of the high-speed rotor of a micro turbine being an element of the micro power plant in dispersed power engineering based on renewable energy sources are presented in the paper. The basic problem of such devices is to assure a stable rotor operation within the entire range of rotational speeds. Foil bearings and special rotor structure were applied. It turned out that the situation, in that the rotor – after loosing its stability – stabilizes again when the rotational speed increases, is possible. This is a phenomenon determined by the author as multiple whirls. Another topic discussed in the present paper is an assessment of the influence of a random character of certain input data – in this case – changes of external excitations of the system. This problem is related to the so-called heuristic models often placed in opposition to widely used algorithmic models.


Rotor dynamics Nonlinear vibrations Hydrodynamic instability Heuristic problems Computer simulation 


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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  1. 1.Institute of Fluid-Flow Machinery, Polish Academy of SciencesGdansk University of Warmia and MazuryOlsztynPoland

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