NON LINEAR DYNAMIC ANALYSIS OF CYLINDRICAL ROLLER BEARING

Structural vibration of cylindrical roller bearings is one of the most important mechanical sources for vibration and noise generation in vast majority of rotating machines. One of the most complicated and unpredictable non linear behavior of the rotor bearing system is chaos. The proposed research mainly focuses on detecting the chaos in the balanced rotor bearing system. Because of very less research work in case of cylindrical roller bearing, the authors have decided to work on cylindrical roller bearing (NJ 305). The study is going to be done in three steps. First step is development of mathematical model by considering the nonlinearity, second is numerical solution of coupled nonlinear equations and finally, analysis of dynamic behavior of motion by using various tools. The non-linearity in the rotor bearing system has been considered mainly due to radial internal clearance and Hertzian stress. The internal radial clearance is the cause of parametric vibration. The mathematical model is going to be developed by considering both nonlinear contact stiffness and damping at the Hertzian contact between rollers and races. The numerical integration technique Runge-Kutta-Fourth-Order method is used to solve the coupled nonlinear differential equations iteratively. Various techniques like Time-displacement response plot, Orbits plots, Poincare map and power spectra will be to detect the chaotic motion. The programme code will be developed in the MATLAB software to solve the nonlinear equation of motion and to get the different plots. At the particular speed, the rotor bearing system has chaotic motion. With the help of analysis tools, different routes to chaos like periodic doubling (subharmonic route to chaos), quasiperiodic and intermittency are identified. (C) 2017 The Authors. Published by Elsevier Ltd.