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Technical Briefs

Flow-Induced Instability on High-Speed Mini Rotors in Laminar Flow

[+] Author and Article Information
Emre Dikmen

e-mail: edikmen@gmail.com

André de Boer

Faculty of Engineering Technology,
Section of Applied Mechanics,
University of Twente, P.O. Box 217,
7500 AE Enschede, The Netherlands

Ben Jonker

Faculty of Engineering Technology,
Section of Mechanical Automation,
University of Twente, P.O. Box 217,
7500 AE Enschede, The Netherlands

1Corresponding author.

Contributed by the Design Engineering Division of ASME for publication in the Journal of Vibrations and Acoustics. Manuscript received May 21, 2010; final manuscript received September 23, 2012; published online February 25, 2013. Assoc. Editor: Yukio Ishida.

J. Vib. Acoust 135(2), 024502 (Feb 25, 2013) (5 pages) Paper No: VIB-10-1132; doi: 10.1115/1.4023050 History: Received May 21, 2010; Revised September 23, 2012

In this study, a modeling approach is developed to examine laminar flow effects on the rotordynamic behavior of high-speed mini rotating machinery with a moderate flow confinement. The existing research work mostly focuses on the flow-induced forces in small gap systems, such as bearings and seals, in which the flow is mostly laminar and inertia effects are ignored. In other studies, medium gap systems are analyzed, taking the inertia effects into consideration, but the surrounding flow is considered as turbulent. However, in high speed mini rotating machinery, the large clearances and the high speeds make the inertia effects significant, even in the laminar flow regime. In the current study, the flow-induced forces resulting from the surrounding fluid are analyzed and these models are combined with the structural finite element (FE) models for determining the rotordynamic behavior. The structure is analyzed with finite elements based on Timoshenko beam theory. Flow-induced forces, which include inertia effects, are implemented into the structure as added mass-stiffness-damping at each node in the fluid confinement. The shear stress is modeled with empirical and analytical friction coefficients, and the stability, critical speeds, and vibration response of the rotor is investigated for different friction models. In order to validate the developed modeling approach, experiments were conducted on a specially designed setup at different support properties. By comparing the experiments with the theoretical models, the applicability of the different friction models are examined. It was found that the dynamic behavior is estimated better with empirical friction models compared to using the analytical friction models.

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References

Dikmen, E., van der Hoogt, P., de Boer, A., and Aarts, R., 2010, “Influence of Multiphysical Effects on the Dynamics of High Speed Mini Rotors, Part I: Theory,” ASME J. Vibr. Acoust., 132, p. 031010. [CrossRef]
Epstein, A., 2004, “Millimeter-Scale, Micro Electro-Mechanical Systems Gas Turbine Engines,” ASME J. Eng. Gas Turbines Power, 126, pp. 205–226. [CrossRef]
Lin, R. M., and Wang, W. J., 2006, “Structural Dynamics of Microsystems—Current State of Research and Future Directions,” Mech. Syst. Signal Process., 20, pp. 1015–1043. [CrossRef]
Meng, G., Zhang, W. M., Huang, H., Li, H. G., and Chen, D., 2009, “Micro-Rotor Dynamics for Micro-Electro-Mechanical Systems (MEMS),” Chaos, Solitons Fractals, 40, pp. 538–562. [CrossRef]
Muszynska, A., 2005, Rotordynamics, Taylor and Francis, London.
San Andrés, L., 2008, Modern Lubrication Theory-Lecture Notes, Texas A&M University, College Station, TX.
Childs, D., 1993, Turbomachinery Rotordynamics: Phenomena, Modeling, and Analysis, Wiley, New York.
Athavale, M., and Przekwas, A., 1994, “A CFD Code for Analysis of Fluid Dynamic Forces in Seals,” NASA. Workshop on Seals and Flow Code Development-1993, NASA CP-10136.
Hendricks, R. C., Przekwas, A., Tam, L. T., Muszynska, A., Braun, M. J., and Mullen, R. J., 1988, “Numerical Modeling of Multidimensional Flow in Seals and Bearings Used in Rotating Machinery,” National Aeronautics and Space Administration, Lewis Research Center, Technical Report No. TM-100779.
Staubli, T., and Bissig, M., 2001, “Numerically Calculated Rotor Dynamic Coefficients of a Pump Rotor Side Space,” International Symposium on Stability Control of Rotating Machinery (ISCORMA), South Lake Tahoe, CA, August 20–24.
Athavale, M., Hendricks, R. C., and Steinetz, B. M., 1995, “Numerical Simulation of Flow in a Whirling Annular Seal and Comparison With Experiments,” National Aeronautics and Space Administration, Lewis Research Center, Technical Report No. TM-106961.
Fritz, R. J., 1970, “The Effects of an Annular Fluid on the Vibrations of a Long Rotor, Part 1—Theory,” ASME J. Basic Eng., 92, pp. 923–929. [CrossRef]
Antunes, J., Axisa, F., and Grunenwald, T., 1996, “Dynamics of Rotors Immersed in Eccentric Annular Flow. Part I: Theory,” J. Fluids Struct., 10, pp. 893–918. [CrossRef]
Grunenwald, T., Axisa, F., Bennett, G., and Antunes, J., 1996, “Dynamics of Rotors Immersed in Eccentric Annular Flow. Part II: Experiments,” J. Fluids Struct., 10, pp. 919–944. [CrossRef]
Genta, G., 2005, Dynamics of Rotating Systems, Springer, New York.
Genta, G., 1985, “Consistent Matrices in Rotor Dynamics,” Meccanica, 20, pp. 235–248. [CrossRef]
Grunenwald, T., 1994, “Comportement Vibratoires d'arbres de Machines Tournantes dans un Espace Annulaire de Fluide de Confinement de Modéré,” Ph.D. thesis, Paris University, Paris.
Brennen, C., 1994, Hydrodynamics of Pumps, Concepts ETI, Norwich, VT.
Bilgen, E., and Boulos, R., 1973, “Functional Dependence of Torque Coefficient of Coaxial Cylinders on Gap Width and Reynolds Numbers,” ASME J. Fluids Eng., 95(1), pp. 122–126. [CrossRef]
Dikmen, E., van der Hoogt, P., de Boer, A., and Aarts, R., 2010, “Influence of Multiphysical Effects on the Dynamics of High Speed Mini Rotors—Part II: Results,” ASME J. Vibr. Acoust., 132, p. 031011. [CrossRef]

Figures

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Fig. 2

Models of friction coefficients versus Reynolds number

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Fig. 3

The complete experimental setup

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Fig. 4

Spectrum map-support beam length: 80 mm

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Fig. 5

Onset of instability with different friction models-support beam length: 80 mm

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