Natural Frequencies of Several Bladed Discs on the Shaft

• Autorzy: Rządkowski R. , Drewczyński M.
• Języki publikacji: EN

Abstrakty

EN

The effect of multistage coupling on the dynamics of a rotor consisting of eight bladed discs on a solid shaft is considered. Free vibrations are examined using finite element representations of rotating single blades, bladed discs, and the complete rotor. In this study, the global rotating mode shapes of flexible tuned bladed discs-shaft assemblies are calculated. Rotational effects, such as centrifugal stiffening are accounted for, and all the possible couplings between the flexible parts are allowed. The gyroscopic effects are included. The calculated natural frequencies obtained from the blade, the shaft, the bladed disc, and the complete shaft with discs are carefully examined to discover resonance conditions and the coupling effects. It was found that the flexible modes of the tuned bladed discs affected by shaft motion are those with zero, one and two nodal diameters. In these modes the shaft deflection is clearly visible. The findings of this paper suggest that multistage analysis may be required for proper calculations of free vibration of bladed discs.

Słowa kluczowe

EN

shaft; rotor; bladed disc

PL

wirnik; szyb

• Wydawca: Wydawnictwo Politechniki Łódzkiej
• Czasopismo: Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka
• Rocznik: 2005
• Tom: nr 128, vol. 2
• Strony: 457--470
• Opis fizyczny: Bibliogr. 18 poz.

Twórcy

autor

Rządkowski R.

• Department of Dynamics of Machines, Institute of Fluid Flow Machinery, Poland Academy of Sciences, Gdansk

autor

Drewczyński M.

• Department of Dynamics of Machines, Institute of Fluid Flow Machinery, Poland Academy of Sciences, Gdansk

Bibliografia

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