Wind tunnel experimental investigation on aerodynamic noise characteristics of full-scale pantographs with single or double contact strips

Abstract

As the train speed continuous increase, the noise caused by high-speed trains has long troubled residents along the railway. The pantograph protrudes from the surface of the train and is the main source of train aerodynamic noise. This study aims to understand the aerodynamic noise characteristics of pantographs to assist in the development of higher-speed trains, the aerodynamic noise from two types of full-scale pantographs with single contact strip and double contact strips was measured using various microphones in wind tunnel tests, and a comparative analysis was conducted. Subsequently, based on the analysis results and engineering experience, a new low-noise pantograph design idea is proposed. The research results are as follows: The spatial distribution of the main noise source is affected by both model and operation status of the pantograph. Based on the noise map of specific frequencies, the panhead and base frame have been identified as the primary noise sources. Due to the complex structure of the arm knuckle in the double contact strips pantograph, it is prone to generating high-intensity noise. Both distribution and intensity of the surface acoustic load in the panhead area of the pantograph with the single contact strip are significantly affected by the operation status, with differences in overall sound pressure level reaching up to 15 dB. In the airflow speed range of 160 km/h to 324 km/h, the overall sound energy of the pantograph far-field noise increases with the speed raised to the power of 5.60–6.01. For pantographs designed for speeds of up to 400 km/h, a streamlined design and optimization on the base frame are very necessary. The data and conclusions obtained in this study are highly significant for guiding the use, design, and noise control of pantographs for high-speed trains.