Eventos Anais de eventos
COBEM 2017
24th ABCM International Congress of Mechanical Engineering
Analysis of the bearings’ influence on the dynamic behavior of a rotating machine
Submission Author:
César Rother , SP
Co-Authors:
Tiago Machado, César Rother
Presenter: César Rother
doi://10.26678/ABCM.COBEM2017.COB17-0366
Abstract
This work is about the analysis of dynamic behavior of rotating machines employing the finite element method. It aims on evaluating the bearings model influence in the rotor’s performance. A computational code - that allows testing several simplifying hypotheses such as bearing model simplification - was written in order to do all the tests. Shaft and disc elements are modeled based on Timoshenko beam theory. Bearings are modeled with both rigid and hydrodynamic options. The hydrodynamic bearing is modeled by the solution of Reynolds equation for short bearing, in order to obtain approximations of damping and stiffness coefficients that represent the oil film. Analyzes are done in frequency domain (FRF), time domain (orbits) and modal domain (Campbell diagram). Two types of rotors are studied: rotor with centralized and decentralized disc - supported at both ends. The preliminary results showed the considerable effect of bearing modeling on the dynamic behavior of the rotor, by changing the natural frequencies and the vibration amplitudes.
Keywords
Rotordynamics, Hydrodynamic bearings, Vibration Analysis, Finite Element Method
