Vibration Analysis of the Gas Turbine Considering Dependency of Stiffness and Damping on Frequency

In this paper the complete rotor system including elastic shaft with distributed mass, allowing for the effects of oil film in bearings. Also, flexibility of foundation is modeled. As a whole this article is a relatively complete research in modeling and vibration analysis of rotor considering gyroscopic effect, damping, dependency of stiffness and damping coefficients on frequency and solving the vibration equations including these parameters. On the basis of finite element method and utilizing four element types including element of shaft, disk, bearing and foundation and using MATLAB, a computer program is written. So the responses in several cases and considering different effects are obtained. Then the results are compared with each other, with exact solutions and results of other papers.

Authors:

• Hamed Jamshidi
• Pooya Djamshidi

Keywords:

• Damping coefficients
• Finite element method
• Modeling
• Rotor vibration

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