Study of Effect of Unbalanced Forces for High Speed Rotor

The present paper deals with the study of dynamic behavior of unbalanced rotor along with internal radial clearance (IRC-C3) as non-linearity. Even though the perfect alignment and precision manufacturing has been done, unbalance forces cannot be eliminated completely. The dynamic behavior of a high speed unbalanced rotor has been studied for the deep groove ball bearing having the internal radial clearance of class 3. The complex mathematical model simulates nonlinear vibrations due to both nonlinear contact stiffness and damping at the contact of balls and races. The contact of rollers with races are treated as nonlinear springs with contact damping whose stiffnesses are obtained by using Hertzian elastic contact deformation theory. The explicit type numerical integration technique Runge- Kutta-Fourth-Order method is used to solve the coupled nonlinear differential equations iteratively. Various techniques like Poincare maps, orbit plots and power spectra are used to study the nature of response. The quasiperiodic behavior is a route to chaos.