Mathematical modeling of centrifugal machines rotors seals for the purpose of assessing their influence on dynamic characteristics

: pp. 422–431
Received: October 27, 2020
Revised: May 10, 2021
Accepted: June 03, 2021
Pukhov Institute for Modelling in Energy Engineering of the National Academy of Sciences of Ukraine

With an increase of equipment parameters, such as the pressure of the sealing medium and the speed of shaft rotation, the problems  ensuring its hermetization efficiency are rising up.  In addition to hermetization itself, the sealing system affect the overall operational safety of the equipment, especially vibratory.  Groove seals are considered as hydrostatodynamic supports capable of effectively damping rotor oscillations.  To determine the dynamic characteristics, models of grooved seals and single-disc rotors with grooved seals are examined.  The obtained analytical dependences for computation of dynamic characteristics for the hydromechanical rotor-seals system, describing radial-angular oscillations of the centrifugal machine rotor in groove seals are presented as well as the formulas for computation of amplitude frequency characteristics.  An example for the computation dynamic characteristics of one of the centrifugal machine rotor models is drawn.

  1. Martsynovskyi V. A., Shevchenko S. S.  Pumps of nuclear power plants: calculation, design, operation.  Monograph, PF "University Book" Publishing House (2018).
  2. Simonovskiy V. I.  Refinement of mathematical models of oscillatory systems according to experimental data.  Sumy State University (2010).
  3. Simonovskiy V. I.  Evaluation of coefficients of mathematical models for oscillatory systems.  ALAP LAMBERT Academic Publishing (2015).
  4. Gadyaka V. G., Leikych D. V., Simonovskiy V. I.  Phenomena of stability loss of rotor rotation at tilting pad bearings.  Hermetic, Vibration Reliability and Ecological Safety of Pump and Compressor Machinery. 244–253 (2011).
  5. Ishida Y., Yamamoto T.  Linear and nonlinear rotordynamnics. A modern treatment with applications.  Verlag, Willey-VCH (2012).
  6. Gadyaka V. G., Simonovskiy V. I.  Estimation of segment bearing stiffness while balancing flexible rotors for turbo-charge units in the accelerating-balancing stand.  Bulletin of Sumy National Agrarian University, Series "Mechanization and Automation of Industrial Processes". 11, 145–150 (2005).
  7. Jin C., Xu Y., Zhou J., Cheng C.  Active magnetic bearings stiffness and damping identification from frequency characteristics of control systems.  Hindawi Publishing Corporation (2016).
  8. Wang T., Wang F., Bai H., Cui H.  Stiffness and critical speed calculation of magnetic bearing-rotor system based on FE.  Electrical machines and systems. IEEE Xplore (2008).
  9. Villa C., Sinou J., Thouverez F.  Stability and vibration analysis of a complex flexible rotor bearing system.  Communications in Nonlinear Science and Numerical Simulation. 13 (4), 804–821 (2008).
  10. Bai C., Zhang H., Xu Q.  Subharmonic resonance of a symmetric ball bearing-rotor system.  International Journal of Non-Linear Mechanics. 50, 1–10 (2013).
  11. Pavlenko I. V., Simonovsky V. I., Pitel’ J., Verbovyi A. E., Demianenko M. M.  Investigation of critical frequencies of the centrifugal compressor rotor with taking into account stiffness of bearings and seals.  Journal of Engineering Sciences. 1, 1–6 (2017).
  12. Martsynovskyi V. A.  Groove seals: theory and practice.  Printing service of Sumy State University (2005).
  13. Kundera C., Marcinkowski W. A.  The effect of the annular seal parameters on the dynamics of the rotor system.  Int. Journal of Applied Mechanics and Engineering. 15 (3), 719–730 (2010).
  14. Shevchenko S. S., Shevchenko M. S.  Mathematical modeling of centrifugal machines rotors seals as dynamic systems.  Bulletin of the National Technical University "Kharkov Polytechnic Institute".  Series "Informatics and Modeling". 4, 85–102 (2020).
Mathematical Modeling and Computing, Vol. 8, No. 3, pp. 422–431 (2021)