Influence of vibration conectedness on eigenmode shapes of bladed disks with non-identical blades
- Authors: Ermakov A.I.1, Urlapkin A.V.1, Fedorchenko D.G.2
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Affiliations:
- Samara State Aerospace University
- JSC «Metallist-Samara»
- Issue: Vol 13, No 5-3 (2014): Special Issue
- Pages: 76-81
- Section: ISSUE WITHOUT SECTION
- URL: https://journals.ssau.ru/vestnik/article/view/2544
- DOI: https://doi.org/10.18287/1998-6629-2014-0-5-3(47)-76-81
- ID: 2544
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Abstract
The paper discusses the vibrations of bladed disks with non-identical blades. Eigenvalues of this disks due to violation of rotational symmetry is always the case of the harmonic distortion of the distribution of the displacement along the circumference (the eigenvalues distortion). It has been established that the magnitude of distortion, and hence the degree of disruption of rotational symmetry of a wheel depends not only on how much different vanes from one another, but also from connection oscillations. By the calculation and experimental way it is studied distortion of eigenvaluesof bladed disks in violation of rotational symmetry with decreasing vibration connectedness up (by increasing the thickness of the disk) to its complete disappearance on an example of a model bladed disk.Introduced a coefficient of quantitatively assessing the value of the degree of violation of rotational symmetry. As an example of mode shapes represented by the bladed disks of the NK-12 compressor. A decrease in the vibration connectedness leads to a distortion in the beginning of the distribution of the harmonic offsets, and then to localize forms. It was noted that localized forms are not self-equilibrated and may lead to excitation of oscillations of the rotor.
About the authors
A. I. Ermakov
Samara State Aerospace University
Author for correspondence.
Email: fdla@ssau.ru
Doctor of Science (Engineering), Professor
Russian FederationA. V. Urlapkin
Samara State Aerospace University
Email: urlapkin@gmail.com
Engineer of sectoral research laboratory "Vibration resistance and reliability of aeronautical products"
Russian FederationD. G. Fedorchenko
JSC «Metallist-Samara»
Email: dgfedorchenko@yandex.ru
Candidate of Science (Engineering)
Chief designer
Russian FederationReferences
- Ivanov V.P. Kolebaniya rabochikh koles turbomashin [Vibrations of Bladed Disks in Turbomachinery]. Moscow: Mashinostroenie Publ., 1983. 224 p.