Review study of main sources of noise generation at wheel-rail interaction

Abstract

Railways are very economical and efficient long-distance transportation systems in many high-density populated countries. However, in terms of environmental safety, different countries announced an increasing traffic noise near residential area. The relative importance of wheel-rail noise to overall train noise plays a crucial role in developing railway transportation. Generally, there are three types of noise at wheel-rail interaction: rolling noise, impact noise, and squeal noise. Rolling noise refers to vertical vibration excitation on straight track due to the undulations of the wheel and rail surfaces. TWINS as the most advanced model up to date can provide total noise prediction within 2 dB compared to full-scale experiments. The impact noise happens when wheel is running on the rail surface discontinuities. Since linear noise generation assumption is employed at contact patch and non-linear contact element is ignored, impact noise due to large roughness are rarely developed and they need to be extended to the reasonable higher frequencies (5 kHz). The squeal noise is usually due to lateral excitation mechanism and always occurs on sharp radius curves. Due to the complexity of wheel-rail noise generation mechanisms, the almost all existing prediction models either have not been validated or they are bounded to predict noise under limited conditions and certain frequency ranges. In this paper, the differences between three main sources of noise generation at wheel-rail interaction will be reviewed.