Vibration prediction and failure analysis based on refined modeling of turbocharging rotor system with variable cross sections
Light Alloy Research Institute, Central South University, 410083, Changsha, China
2 State Key Laboratory of High Performance Complex Manufacturing, Central South University, 410083, Changsha, China
Accepted: 17 December 2021
Published online: 28 December 2021
This paper proposes a general refined modeling method to establish the mathematical model of the turbocharger flexible rotor system for exact dynamics prediction and failure analysis. Based on the FE method and Guyan matrix reduction, the mathematical model of the rotor with multiple variable cross sections is developed. Then, the motion governing equation of the rotor-bearing system is derived by combining the refined rotor model with the floating ring equation. In order to verify the modeling method, a series of comparisons of simulations and tests are introduced. In addition, the reasons for the enlargement of compressor end bearing inner clearance are revealed. After that, the influence of the bearing inner clearance on the vibration characteristics is discussed, while the rotor with and without unbalance defect is considered. The results show that the variation of the bearing inner clearance will not only affect the stability, but also the overall amplitude as well as 3D processional orbits. The usage of the proposed rotor modeling method is more time efficient compared to the common modeling methods and is capable to effectively perform parametric studies. The research is helpful to predict dynamic behaviors of complex rotors more accurately and prevent from failure.
© The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2021