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

2021;
: pp. 422–431
https://doi.org/10.23939/mmc2021.03.422
Received: October 27, 2020
Revised: May 10, 2021
Accepted: June 03, 2021
Authors:
1
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.

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Mathematical Modeling and Computing, Vol. 8, No. 3, pp. 422–431 (2021)