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Meccanica

, Volume 2, Issue 4, pp 243–255 | Cite as

On the instability of parametrically excited two degrees of freedom vibrating systems with viscous damping

  • Emilio Massa
Article

Summary

The stability of vibrating systems having two degrees of freedom subjected to parametric excitation and with viscous damping are studied with a special perturbation method.

Analytical expressions in explicit form in second approximation are obtained for the transition from stability to instability. A general criterion for judging the limits within which the approximation is acceptable is indicated.

It is shown that even in parametrically excited vibrating systems damping can have a destabilising effect similar to the destabilising effect known to exist in nonconservative elastic systems.

Keywords

Mechanical Engineer Civil Engineer Explicit Form Perturbation Method General Criterion 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Sommario

Nel presente lavoro si esamina con un particolare metodo di perturbazione la stabilità dei sistemi vibranti a due gradi di libertà eccitati parametricamente e con resistenza viscosa.

Si ottengono espressioni analitiche in forma esplicita in seconda approssimazione dei confini fra stabilità ed instabilità. Si dà anche un criterio di massima per giudicare entro quali limiti l'approssimazione risulta accettabile.

Si pone in evidenza come anche nelle vibrazioni eccitate parametricamente lo smorzamento possa avere un effetto instabilizzante analogo a quello già noto nei sistemi elastici non conservativi.

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References

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Copyright information

© Tamburini Editore s.p.a 1966

Authors and Affiliations

  • Emilio Massa
    • 1
  1. 1.Politecnico di MilanoItaly

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