Noise Control and Dynamic Life Rating Improvement of Rolling Bearing

Abstract

The Global Automobile sector is shifting towards electric mobility due to carbon footprint and eco solutions. One of the essential requirements is low noise motor bearings and optimization of the acoustic behaviour of the system due to the replacement of internal combustion engines by battery-operated high-speed induction motors. Most of the electric motor manufacturers report the challenges related to the noise from bearings. This research is carried out in National Bearing Company (NBC), which is typically an Indian leading bearing manufacturer that produces millions of bearings for the application of automobiles, railways, and aerospace. The research is related to the bearing rejection due to noise, one of the challenging problems in the export market. In India, electric vehicles are a new era for research. Majority of the rotating parts are imported from European and Chinese bearing suppliers to manufacture an electric vehicle in India. As make in India and self-alliance norms, this problem is identified for the area of the research in bearing acoustics. newlineIn the present work, a mathematical model to predict high-speed bearing acoustic responses has been developed and demonstrated in induction motors. The mathematical model has been simulated using coupled governing equations with the help of the Runge-Kutta method. The effect of the acoustic behaviour of bearing has been studied by modifying the internal geometry, such as the number of rotating elements, curvature ratio, and rotating speed with the track raceway s oval shape pre-operational damage. The mathematical model predicts the contact stress, elliptical contact area, noise level (dB), and frequencies of waviness pattern. High-speed bearing is tested at four different speeds to monitor acoustic behaviour. The simulation and experimental results are presented in the form of a waterfall diagram, FFT spectrum, and color pressure plots. Results indicate the remarkable influence of raceway nonconformities of bearing on the noise level. The research study s no