Controllable magnetically sensitive rotor support element for reducing oscillation and force transmission
The hydrodynamic bearings are used to support rotors for their high loading capacity, simple design, and quiet operation. To increase stability limit of lateral vibration of rotating machines, the hydrodynamic bearings are combined with classical squeeze film dampers. This technological solution is widely used to support rotors of high speed turbomachinery. The amount of damping in the rotor supports influences suppression of the vibration amplitude and magnitude of the force transmitted between the rotor and its stationary part. A simple dynamical analysis shows that to achieve optimum performance of the damping elements of rotors working in a wide range of operating speeds, their damping effect must be adaptable to the current angular velocity. This is possible if the classical squeeze film dampers are replaced with controllable damping devices. The presented article deals with a proposal and investigation of a new type of such support element that is a combination of a hydrodynamic bearing and of a magnetorheological squeeze film damper and with its application for rigid rotors. The computational simulations show that higher damping is needed for lower rotor velocities and lower one for higher speeds to achieve optimum compromise between the vibration attenuation and minimization of the force transmitted between the rotor and the stationary part. The results also show that damping in the rotor supports has almost no influence on the rotor oscillation amplitude for higher angular velocity. The proposal of the novel controllable rotor support element, the development of its mathematical model, and learning more on its effect on vibration attenuation and on the force transmission are the principal contributions of the research work carried out.
KeywordsNew Controllable Support Element Combination of a Hydrodynamic Bearing and a Magnetorheological Damper Mathematical Model Computational Simulations Vibration Attenuation Force Reduction
Unable to display preview. Download preview PDF.
This work was supported by the Czech Science Foundation (grant project 19-06666S), by the Ministry of Education, Youth and Sports within the National Programme of Sustainability (NPU II, project LQ1602 - IT4Innovations excellence in science), and by the project of conceptual development of research organizations RVO: 61388998.
- 1.Zapoměl, J., Ferfecki, P. Kozánek, J.: Determination of the transient vibrations of a rigid rotor attenuated by a semiactive magnetorheological damping device by means of computational modelling. Appl. Comput. Mech. 7, 223-234 (2013).Google Scholar
- 2.Mu, C., Darling, J., Burrows, C.R.: An appraisal of a proposed active squeeze film damper. ASME J. Tribol. 113, 750-754 (1991).Google Scholar
- 3.El-Shafei, A., El-Hakim, M.: Experimental investigation of adaptive control applied to HSFD supported rotors. ASME J. Eng. Gas Turbine Power 122, 685-692 (2000).Google Scholar
- 4.Tonoli, A., Silvagni, M., Amati, N., Staples, B., Karpenko, E.: Design of electromagnetic damper for aero-engine applications. Proceedings of the International Conference on Vibration in Rotating Machinery, Exeter, England, pp. 761-774 (2008).Google Scholar
- 5.Morishita, S., Mitsui, J.: Controllable squeeze film damper (An application of electro-rheological fluid). ASME Journal of Vibration and Acoustics, 114, 354-357 (1992).Google Scholar
- 6.Aravindhan, T.S., Gupta, K.: Application of magnetorheological fluid dampers to rotor vibration control. Adv. Mech. Eng. 5, 369-380 (2006).Google Scholar
- 7.Zapoměl, J., Ferfecki, P., Forte, P.: A new mathematical model of a short magnetorheological squeeze film damper for rotordynamic applications based on a bilinear oil representation - derivation of the governing equations. Appl. Math. Model., 52, 558-575 (2017).Google Scholar
- 8.Ferfecki, P., Zapoměl, J., Kozánek, J.: Analysis of the vibration attenuation of rotors supported by magnetorheological squeeze film dampers as a multiphysical finite element problem. Adv. in Eng. Soft., 104, 1-11 (2017).Google Scholar
- 9.Zapoměl, J.: Computer Modelling of Lateral Vibration of Rotors Supported by Hydrodynamical Bearings and Squeeze Film Damper. 1st ed. VŠB-Technical University of Ostrava, (in Czech) (2007).Google Scholar
- 10.Nataraj, C., Nelson, H. D.: Periodic Solutions in Rotor Dynamic Systems with Nonlinear Supports: A General Approach. J. Vib. Acoust. Stress Realib. Des. 111, 187-193 (1989).Google Scholar