On the instability threshold of journal bearing supported rotors
Ricardo Ugliara Mendes, Katia Lucchesi Cavalca
ARTIGO
Inglês
Journal bearing supported rotors present two kinds of self-excited vibrations: oil-whirl and oil-whip. The first one is commonly masked by the rotor unbalance, hence being rarely associated with instability problems. Oil-whip is a severe vibration which occurs when the oil-whirl frequency coincides...
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Journal bearing supported rotors present two kinds of self-excited vibrations: oil-whirl and oil-whip. The first one is commonly masked by the rotor unbalance, hence being rarely associated with instability problems. Oil-whip is a severe vibration which occurs when the oil-whirl frequency coincides with the first flexural natural frequency of the shaft. In many cases, oil-whip is the only fluid-induced instability considered during the design stage; however, experimental evidences have shown that the instability threshold may occur much sooner, demanding a better comprehension of the instability mechanism. In this context, numerical simulations were made in order to improve the identification of the instability threshold for two test rig configurations: one on which the instability occurs on the oil-whip frequency, and another which became unstable before this threshold. Therefore, the main contribution of this paper is to present an investigation of two different thresholds of fluid-induced instabilities and their detectability on design stage simulations based on rotordynamic analysis using linear speed dependent coefficients for the bearings
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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQ
131658/2010-7
FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP
2007/54647-4
COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPES
Aberto
DOI: https://doi.org/10.1155/2014/351261
Texto completo: https://www.hindawi.com/journals/ijrm/2014/351261/
On the instability threshold of journal bearing supported rotors
Ricardo Ugliara Mendes, Katia Lucchesi Cavalca
On the instability threshold of journal bearing supported rotors
Ricardo Ugliara Mendes, Katia Lucchesi Cavalca
Fontes
International journal of rotating machinery (Fonte avulsa) |