The self-oscillation in the vertical rotor system mounted on elastic supports


In this pap er, we study the causes of self-excited oscillations (self-oscillations) and their furtherb ehavior, since these oscillations are the main cause of instability of vertical rotor systemsmounted on sliding b earings. The cause of the self-excited oscillations are hydro dynamic forcesarising from the lubricating layer b etween the b earing and its spike. Based on the classicalmetho ds of the theory of oscillations and the Sommerfeld hyp othesis of a lubricating layer insliding b earings, nonlinear equations of motion of a vertical rotor system were obtained. Theobtained nonlinear differential equations of rotor motion and supp orts do not have an exactsolution. The study is carried out by numerical metho ds. The dep endences of the amplitudes ofthe rotor and b earings on the viscosity of the oil in the b earing, on the size of the gap, on the massof the b earings, on the stiffness and on the damping co efficients are obtained. The results of thestudy of this work allow us to accurately determine and predict all the necessary characteristicsof the working pro cess of this system. The results of the work confirm the physical meaning ofthe pro cess considered in the problem, which can justify the use of this mathematical mo del inthe design of vertical rotor systems on sliding b earings.


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How to Cite
KYDYRBEKULY, A. B.; IBRAYEV, Gulama-Garip Alisher. The self-oscillation in the vertical rotor system mounted on elastic supports. Journal of Mathematics, Mechanics and Computer Science, [S.l.], v. 105, n. 1, p. 160-173, apr. 2020. ISSN 2617-4871. Available at: <>. Date accessed: 07 june 2020.
Keywords self-excited oscillations, self-oscillations, sliding bearing, Sommerfeld hypothesis, otor system, nonlinear equations