NONLINEAR VIBRATION OF ROTOR-BEARING SYSTEM WITH SQUEEZE FILM DAMPING

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Nonlinear Vibration of rotor-bearing system with squeeze film damping.pdf

Date

2022-8-31

Author

Sevencan, Furkan

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Squeeze film damper is a widely used nonlinear element in rotor-bearing systems. The dynamic behavior of the rotor-bearing system supported by the squeeze film damper must be investigated for proper design and analysis. Nonlinear vibration response of rotor systems supported by squeeze film damper due to unbalance is investigated. The system rotordynamic model is developed using 1D Timoshenko beam elements. Three types of modeling are performed for SFD. The nonlinear SFD models are based on the analytical solution of the Reynolds equation for open ends short length SFDs and the numerical solution of the 3D Reynolds equation of flow model by using the Finite Difference Method (FDM) for open ends SFDs by considering oil inertia effects. As FDM is computationally cost, a neural network study is performed for various parameters related to SFD. Finally, Neural Network simulation is performed using data set obtained from the 3D Reynolds equation of flow model using the Finite Difference Method (FDM) for open ends SFDs. Rotor-bearing system and SFD are incorporated, and a nonlinear equation of motion is obtained. Harmonic Balance Method (HBM) takes place to represent the resulting nonlinear differential equations of motion as a set of nonlinear algebraic equations. Newton Method with arc-length continuation is utilized as the solution method for the set of nonlinear algebraic equations obtained. Case studies are performed to investigate the effects of SFD parameters and compare SFD modeling approaches in accuracy and computational time.

Subject Keywords

Rotordynamic, Squeeze Film Damper, Nonlinear Vibrations

URI

https://hdl.handle.net/11511/99656

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

F. Sevencan, “NONLINEAR VIBRATION OF ROTOR-BEARING SYSTEM WITH SQUEEZE FILM DAMPING,” M.S. - Master of Science, Middle East Technical University, 2022.