LATERAL VIBRATION OF A ROTOR/BEARING SYSTEM WITH AXIAL RUBS
DING Qian (Department of Mechanics, Tianjin University, Tianjin 300072, China)
The lateral vibration of a rotor/bearing system influenced by axial contact between disk and stator are investigated by numerical simulation. The contacting forces are equated by two parallel forces with equal magnitude, which act at two bearings laterally and form a couple. One-parametric model is then used to calculate the axial-contact-induced dry friction forces. Supposing the contact occurs at one of the two specified positions, lateral vibrations of the system are calculated at three values of speed which represent the states before and after the passage of the shaft's natural speed, and before the occurrence of the oil whirl, respectively. Results show that the sizes of the axle-necks' orbits can be enlarged and reduced as the initial compressing displacement is increased. When contacts occur at the edge of disk in horizontal plane, bifurcation diagrams reveal complicated behaviors of the axial-rubbed rotor/bearing system. These include motions with different values of period, quasi-periodic and even chaotic motion.