Eventos Anais de eventos
COBEM 2019
25th International Congress of Mechanical Engineering
A MODEL-BASED CRACK IDENTIFICATION APPROACH
Submission Author:
Leandro Leão , MG
Co-Authors:
Leandro Leão
Presenter: Leandro Leão
doi://10.26678/ABCM.COBEM2019.COB2019-0814
Abstract
In the present contribution, a model-based crack detection approach devoted to rotating machines is investigated. The method can identify the location and depth of transverse cracks in rotating machines by analyzing their lateral vibrations. The rotor model is obtained by using the finite element method, considering the Timoshenko beam theory. The crack is applied considering the Mayes’ model. The identification process is based on the solution of an inverse problem, in which the operational vibration responses of the rotor are correlated with the associated numerical data. An optimization algorithm is formulated to identify cracks with different depths and locations along the rotor model. The vibration responses are continually compared. When the optimization code fits the numerical and the operational vibration responses of the rotor, the location and depth of the crack are identified. The so-called Differential Evolution technique is used to solve the mentioned inverse problem. This method is purely a mathematical approach, performing vector combinations that define new search directions over the objective function. The rotating machine used in this work is composed by a horizontal flexible shaft, containing two rigid discs, and is supported by self-alignment ball bearings located at both ends of the shaft. The results demonstrate the possibility of identifying the location and depth of transverse cracks along the rotor.
Keywords
Rotordynamics, model based approach, crack identification, Mayes' Model
