The self-oscillation in the vertical rotor system mounted on elastic supports
DOI:
https://doi.org/10.26577/JMMCS.2020.v105.i1.14Keywords:
self-excited oscillations, self-oscillations, sliding bearing, Sommerfeld hypothesis, otor system, nonlinear equationsAbstract
In this pap er, we study the causes of self-excited oscillations (self-oscillations) and their further
b ehavior, since these oscillations are the main cause of instability of vertical rotor systems
mounted on sliding b earings. The cause of the self-excited oscillations are hydro dynamic forces
arising from the lubricating layer b etween the b earing and its spike. Based on the classical
metho ds of the theory of oscillations and the Sommerfeld hyp othesis of a lubricating layer in
sliding b earings, nonlinear equations of motion of a vertical rotor system were obtained. The
obtained nonlinear differential equations of rotor motion and supp orts do not have an exact
solution. The study is carried out by numerical metho ds. The dep endences of the amplitudes of
the rotor and b earings on the viscosity of the oil in the b earing, on the size of the gap, on the mass
of the b earings, on the stiffness and on the damping co efficients are obtained. The results of the
study of this work allow us to accurately determine and predict all the necessary characteristics
of the working pro cess of this system. The results of the work confirm the physical meaning of
the pro cess considered in the problem, which can justify the use of this mathematical mo del in
the design of vertical rotor systems on sliding b earings.
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