이동하중 해석을 통한 고속철도의 실내소음 특성 분석

Abstract

The high-speed train is an eco-friendly transportation system with high energy efficiency and convenience. The increase in operating speeds led to various problems related to the noise and vibration generation. The distributed power type trains are being utilized. The distributed arrangement of power engines is expected to cause different characteristics in terms of interior noise compared to concentrative-power-type trains. This study explains the differences in interior noise between concentrative and distributed power type trains. The noise induced on the trains were analyzed by the rail vibration due to moving loads by the train weights. The sound pressure level and spectral characteristics of interior noise were analyzed according to the operating speed. Both the concentrative- power-type and distributed-power-type trains were found to generate low-pitched noise. The distributed- power-type trains demonstrated a wide distribution of noise in high-frequency bands, demonstrating a relatively gradual decrease in intensity with increasing frequency. A structural vibration by harmonic moving loads was utilized to simulate the high-speed train on a straight rail. By deriving the displacement response while reflecting the actual load distribution of the train, the results indicate a similar tendency to the measured interior noise spectral characteristics. These findings indicate the contribution of rail vibration response to the interior noise of high-speed trains.