Modeling of a deep-groove ball bearing with waviness defects in planar multibody system

An approach for dynamic modeling of a deep-groove ball bearing with waviness defects in planar multibody system is presented. The deep-groove ball bearing is modeled by introducing a nonlinear force system that takes into account the contact elastic deformations between the ball elements and raceways. Hertzian contact theory is applied to calculate the elastic deflection and nonlinear contact force. The waviness defect on the bearing’s inner and outer raceways is modeled using a sinusoidal function. A planar slider–crank mechanism containing a deep-groove ball bearing with waviness defects on the raceways is chosen as an example to demonstrate application of the methodologies. Variation of the slider acceleration, crank moment, and bearing equivalent reaction force is used to illustrate the dynamic performance of the mechanism when the effect of the bearing waviness defect is considered. The results indicate that the waviness defect can stimulate vibration of the slider–crank mechanism in its kinematic processes. Such vibrations can lead to noise and affect the stability of the mechanical system motion. For a constant waviness, bearings with different numbers of rolling balls have different amplitudes of vibration of the slider–crank mechanism. Furthermore, the effect of varying the rolling ball number and waviness on the dynamic performance of the slider–crank mechanism is different for bearings in different positions.