Nonlinear analysis of a rub-impact rotor-bearing system with initial permanent rotor bow
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A general model of a rub-impact rotor-bearing system with initial permanent bow is set up and the corresponding governing motion equation is given. The nonlinear oil-film forces from the journal bearing are obtained under the short bearing theory. The rubbing model is assumed to consist of the radial elastic impact and the tangential Coulomb type of friction. Through numerical calculation, rotating speeds, initial permanent bow lengths and phase angles between the mass eccentricity direction and the rotor permanent bow direction are used as control parameters to investigate their effect on the rub-impact rotor-bearing system with the help of bifurcation diagrams, Lyapunov exponents, Poincaré maps, frequency spectrums and orbit maps. Complicated motions, such as periodic, quasi-periodic even chaotic vibrations, are observed. Under the influence of the initial permanent bow, different routes to chaos are found and the speed when the rub happens is changed greatly. Corresponding results can be used to diagnose the rub-impact fault in this kind of rotor systems and this study may contribute to a further understanding of the nonlinear dynamics of such a rub-impact rotor-bearing system with initial permanent bow.
KeywordsInitial permanent bow Nonlinear analysis Rub-impact Rotor-bearing system
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- 9.Shuangbiao L. (2002) Thermomechnical contact analysis of rough bodies. Doctoral dissertation, Northwestern UniversityGoogle Scholar
- 10.Rankine W. (1999). On the centrifugal force of rotating shafts. Engineer 27(2): 304–312 Google Scholar
- 11.Rao J.S. (1996). Rotor dynamics, 3rd edn. New Age International, London Google Scholar
- 12.Lalanne M. and Ferraris G. (1999). Rotor Dynamics Prediction in Engineering. Wiley, New York Google Scholar
- 13.Nicholas J.C. and Gunter E.J. et al. (1976). Effect of residual shaft bow on unbalance response and balancing of a single mass flexible rotor: Part I-Unbalancing response, Part II-Balancing. J. Eng. Power 98(2): 171–181 Google Scholar
- 14.Ehrich F.F. (1992). Handbook of Rotordynamics. McGraw-Hill, New York Google Scholar
- 15.Rao J.S. (2001). A note on Jeffcott warped rotor. Mech. Mach. Theory 36: 63–575 Google Scholar
- 17.Zhang Wen: Dynamic instability of multi-degree-of-freedom flexible rotor systems due to full annular rub. ImechE C252/88, 305–308 (1988)Google Scholar
- 19.Bently, D.E., Yu, J.J., Goldman: Full annular rub in mechanical seals, Part 1-Experimental results. In: Proc. of ISROMAC-8, Honolulu (2000)Google Scholar