On Active Vibrations Control of a Flexible Rotor Running in Flexibly-Mounted Journal Bearings

  • Mohamed M. EimadanyEmail author
Part of the Advanced Structured Materials book series (STRUCTMAT, volume 43)


Increasing demands on rotating machinery in terms of higher running speed, less weight and noise, safety and longevity require well controlled dynamics of the system. This paper addresses a means of actively controlling the synchronous vibrations of a flexible rotor running in flexibly-mounted journal bearings. An isotropic optimal controller of the anisotropic rotor-bearing system in complex state space is designed. The isotropic controller essentially eliminates the backward unbalance response component, leading to circular whirling. Simulation results are presented which demonstrate that the isotropic optimal control is more efficient in controlling unbalance whirl than the conventional optimal control.


Isotropic optimal control Rotating machinery Flexible rotor Synchronous vibration. 



The author would like to thank the Research Center, College of Engineering, King Saud University for supporting this work under grant number 5/429 from SABIC. The assistance and encouragement of the Research Center are very much appreciated.


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Copyright information

© Springer International Publishing Switzerland 2013

Authors and Affiliations

  1. 1.Mechanical Engineering DepartmentKing Saud UniversityRiyadhSaudi Arabia

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