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

Abstract

The self-oscillation in the vertical rotor system mounted on elastic supportsIn this paper, we study the causes of self-excited oscillations (self-oscillations) and their further behavior, since these oscillations are the main cause of instability of vertical rotor systems mounted on sliding bearings. The cause of the self-excited oscillations are hydrodynamic forces arising from the lubricating layer between the bearing and its spike. Based on the classical methods of the theory of oscillations and the Sommerfeld hypothesis of a lubricating layer in sliding bearings, nonlinear equations of motion of a vertical rotor system were obtained. The obtained nonlinear differential equations of rotor motion and supports do not have an exact solution. The study is carried out by numerical methods. The dependences of the amplitudes of the rotor and bearings on the viscosity of the oil in the bearing, on the size of the gap, on the mass of the bearings, on the stiffness and on the damping coefficients are obtained. The results of the study of this work allow us to accurately determine and predict all the necessary characteristics of the working process of this system. The results of the work confirm the physical meaning of the process considered in the problem, which can justify the use of this mathematical model in the design of vertical rotor systems on sliding bearings.

Nonlinear dynamics of rotor of an auto-balancing ball device, considering eccentricity and changes in horizontal axes of rotation

“…General issues of the dynamics of various types of rotors mounted on elastic supports (such as determining the critical speeds for various models of the rotor and supports, stability of partial motions, dynamic characteristics for elastic and combined supports, and the influence of rotor parameters on critical speed) are considered in [1][2][3][4][5][6][7][8][9][10].…”

“…In [10], the issues of stable periodic motions of a vertically located rotor and the causes of the oscillatory motion were considered using classical methods of the theory of nonlinear oscillations. Numerical results were obtained for specific values of the system parameters.…”