Numerical investigation, modelling and vibrational dynamics of an unbalanced rigid rotor with two offset discs levitated by air foil bearings
Siddharth SUMAN, Prabhat KUMAR
Abstract. High speed rotating machines are very useful in several industries and production plants or factories. The rotating components in these machines are usually prone to multiple types of faults. These faults can cause large and heavy amount of vibrations in the assembled rotor systems during its operation. So, there is a need for analyzing the rotor behavior in the presence of faults and their identification. This paper discusses the dynamic behavior of a rigid rotor with two discs at offset positions and mounted on air foil bearings at the ends. In this system, it is assumed that the discrete unbalance fault is present at discs only. The stiffness and damping coefficients of both foil bearings are considered to be different and anisotropic in nature. Considering the forces due to foil bearings, inertia force, discs unbalance force, inertia moment, gyroscopic couple effect, the equations of motion of the rotor system have been derived in the two-dimensional transverse directions. Further, these equations are solved using a model developed in the Simulink platform. The obtained solutions of the equations are the time domain rotor displacement in the vertical and horizontal directions. It would be very interesting to investigate and study the unbalance fault effect and displacement responses with variation in the fault parameters, rotor spin speed, and stiffness and damping parameters of foil bearings.
Keywords
Foil Bearing, Gyroscopic Couple, Moment Equilibrium Method, Rotor, Unbalance
Published online 3/1/2025, 10 pages
Copyright © 2025 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Siddharth SUMAN, Prabhat KUMAR, Numerical investigation, modelling and vibrational dynamics of an unbalanced rigid rotor with two offset discs levitated by air foil bearings, Materials Research Proceedings, Vol. 49, pp 286-295, 2025
DOI: https://doi.org/10.21741/9781644903438-29
The article was published as article 29 of the book Mechanical Engineering for Sustainable Development
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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