Abstract
Dynamic model updating based on finite element method (FEM) has been widely investigated for structural damage identification, especially for static structures. Despite the substantial advances in this method, the key issue still needs to be addressed to boost its efficiency in practical applications. This paper introduces the updating idea into crack identification for rotating rotors, which has been rarely addressed in the literature. To address the problem, a novel Kriging surrogate model-based FEM updating method is proposed for the breathing crack identification of rotors by using the super-harmonic nonlinear characteristics. In this method, the breathing crack induced nonlinear characteristics from two locations of the rotors are harnessed instead of the traditional linear damage features for more sensitive and accurate breathing crack identification. Moreover, a FEM of a two-disc rotor-bearing system with a response-dependent breathing crack is established, which is partly validated by experiments. In addition, the associated breathing crack induced nonlinear characteristics are investigated and used to construct the objective function of Kriging surrogate model. Finally, the feasibility and the effectiveness of the proposed method are verified by numerical experiments with Gaussian white noise contamination. Results demonstrate that the proposed method is effective, accurate, and robust for breathing crack identification in rotors and is promising for practical engineering applications.
Highlights
Rotors are one of the most important components of rotating machines, which are widely used in many engineering fields
A new crack identification method is proposed for rotors with a breathing crack based on the Kriging surrogate model using the crack induced super-harmonic responses from two measurement points
Numerical experiments were carried out to investigate the performance of the proposed method based on a validated finite element rotor model with a breathing crack
Summary
Rotors are one of the most important components of rotating machines, which are widely used in many engineering fields. Cracks in rotors are a very dangerous kind of fault that may lead to a sudden and catastrophic failure of a rotating machine. It is of vital significance to monitor and detect a crack, in order to reduce maintenance cost and avoid failure of a rotating machine. Crack parameter identification can provide a foundation for life prediction of a cracked rotor. A crack in a rotor introduces an additional local flexibility and reduces the overall stiffness. A fatigue crack in a rotor is a breathing type, which makes the stiffness of such a rotor changing with time and causes the system to become nonlinear. A cracked rotor possesses complex dynamic characteristics. Vibration-based crack identification methods can be broadly classified as model-based
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
