Nonlinear dynamic behavior and stability of a rotor/seal system with the dynamic vibration absorber

Abstract

The dynamic vibration absorbers have been applied to attenuate the critical or unbalanced vibration but may create the fluid-induced vibration instability in the rotor/seal system. The major purpose of this study is devoted to the effects of the dynamic vibration absorber on the nonlinear dynamic behavior and stability of the fluid-induced vibration in the rotor/seal system. The dynamic vibration absorber is attached on the shaft in the perpendicular directions. The model of the rotor/seal-dynamic vibration absorber system is established as the modified Jeffcott rotor system, and Muszynska nonlinear seal force is applied. The numerical method is used for the dynamic behavior analysis. The effects of the natural frequency and damping ratio of the dynamic vibration absorber on the dynamic behavior are discussed. The stability of the rotor/seal-dynamic vibration absorber system is judged by the eigenvalue theory. The variations of the instability threshold with the parameters of the dynamic vibration absorber are obtained. The results show that the instability threshold and instability vibration frequency are changed by the dynamic vibration absorber. The parameters of the dynamic vibration absorber must be selected carefully to avoid reducing the instability threshold and causing the instability vibration to occur in advance when the dynamic vibration absorber is applied to attenuate the critical or unbalanced vibration of the rotor/seal system.

Multi-parametric Dynamic Analysis of a Rolling Bearings System

“…where s is a dimensionless frequency, E is a dimensionless parameter of linear imbalance, Zr is a dimensionless amplitude of the rotor, Zf is a dimensionless amplitude of the foundation, K is a dimensionless damping coefficient, C is a dimensionless coefficient of stiffness at the cubic term, R is a cavity radius (see Figs. [2][3][4][5][6][7][8][9][10][11].…”

“…In the design of rotary machines, one of the most important mechanical components described by nonlinear models is elastic support, which ensure operability and reliability of the system [5][6][7]. In this paper, rolling bearings act as elastic supports [8].…”

Applications of Jacobi’s Elliptic Functions in Forced Vibration in Nonlinear Rotor Dynamics

“…In the design of rotary machines, one of the most important mechanical components described by nonlinear models that determines the operability and reliability of the system [24][25][26][27][28] are elastic bearings, in our case, rolling bearings act as elastic bearings. Ignoring the nonlinear properties of bearings alters the results of both qualitatively and quantitatively [23,29,30].…”

“…To date, there are numerous studies of the nonlinear dynamics of rotor systems [23][24][25][26][27][28][29][30]. It must be emphasized that despite the widespread occurrence of such systems, their dynamics have not been sufficiently studied due to the difficulties associated with the need to consider the combined action of factors, such as the influence of a liquid during partial filling, external non-conservative forces, linear and angular imbalances.…”

Eliminating the Fluid‐Induced Vibration and Improving the Stability of the Rotor/Seal System Using the Inerter‐Based Dynamic Vibration Absorber

“…e IDVA has been utilized to the vibration control of the cable [25,26], the offshore wind turbine [27], tall building [28], and so on. e traditional DVA could eliminate the instability vibration in the rotor/seal system [29,30]. e fluid-induced instability elimination of the rotor with the IDVA is proposed in this paper.…”