Dynamic Analysis of a High-Speed Rotor-Ball Bearing System Under Elastohydrodynamic Lubrication

Abstract

The nonlinear dynamic behaviors of a high-speed rotor-ball bearing system under elastohydrodynamic lubrication (EHL) are investigated. First, the numerical curve fittings for stiffness and damping coefficients of lubricated contacts between rolling elements and races are undertaken, and then the fitted formulae are introduced to the equations of motion of the rotor-ball bearing system to investigate its nonlinear characteristics. Furthermore, the time responses, power spectra, phase trajectories, orbit plots, and bifurcation diagrams for cases of ignoring and considering the lubrication condition in bearings are inspected and compared. The results indicate that, when lubrication is taken into account, the amplitudes of vibration displacements and velocities of the rotor system increase, and the appearance of different regions of periodic, quasi-periodic, and chaotic behavior is strongly dependent on the speed and load.

Dynamic Analysis of a Motorized Spindle With Externally Pressurized Air Bearings

“…The complete nonlinear equations pertinent to the rotor-bearing system are integrated by numerical methods to obtain the rotor center orbits corresponding to any specified set of geometrical, running, and initial conditions [12]. The orbit method enables both establishment of the stability threshold and prediction of the behavior of the bearing into the instability region [13][14][15][16][17]. However, the orbit method to solve nonlinear equations is slow and less effective than the perturbation method; as such, it will not be considered in this work.…”

Methodology for the physics-based modelling of multiple rolling element bearing configurations

“…The mathematical modelling of the waviness is also considered to represent the geometrical imperfections. Zhang et al 30 proposed a model for a rotor-bearing system using also a five DOF approach and taking into account the effect of the lubrication by the use of an EHL model in each ball-race contact. Sopanen and Mikkola 24 went beyond this approach and included both waviness and localised defects in their proposed model.…”

“…In particular, single-row deep-groove ball bearings have received the most attention in the research literature. 8–30 There are also dynamic models related to other configurations of single-row ball bearings, such as angular-contact ball bearings. 31–35 A few models for double-row ball bearings have been found in the research literature.…”

Multi-body modelling of rolling element bearings and performance evaluation with localised damage

“…The mathematical modelling of the waviness is also considered to represent the geometrical imperfections. Zhang et al [45] proposed a model for a rotor-bearing system using a five DOF approach and taking into account the effect of the lubrication by using an elastohydrodynamic lubrication (EHL) model in each ballrace contact. Sopanen and Mikkola [39] went beyond this approach and included both waviness and localised defects in their proposed model.…”