Aerodynamic characteristics of the train–SENB (semi-enclosed noise barrier) system: A high-speed model experiment and LES study

Abstract

The aerodynamic effect of a passing high-speed train (HST) may cause structural damage to the semi-enclosed noise barrier (SENB). Moreover, the rapid variation of the aerodynamic environment may deteriorate the operation stability of the train and passenger comfort. Three types of rectangular SENBs, namely, inverted-L-shaped noise barriers installed on double-line railways (ILSNB-DL), inverted-L-shaped noise barriers with a vertical board installed on double-line railways (ILSNBVB-DL) and inverted-L-shaped noise barriers with a vertical board installed on single-line railways (ILSNBVB-SL), are considered in this research. By establishing a 1:16.8 train–SENB moving-model system and a corresponding large eddy simulation (LES) model, the time-history and spatial characteristics, flow field mechanism and spectral characteristics of the aerodynamic pressure acting on the three types of SENBs are investigated. Moreover, the differences in the time-history characteristic, flow field mechanism and spectral characteristic of the aerodynamic loads on the HST when passing through the three types of SENBs are also compared. The aerodynamic pressure inside ILSNBVB-DL is more than 27% higher than that of ILSNB-DL, and the aerodynamic pressure inside ILSNBVB-SL is more than 16% higher than that of ILSNBVB-DL. When the HST enters and exits ILSNBVB-SL, the area with positive and negative pressure on the train surface varies the most dramatically, causing the amplitude of the lift force of the HST when passing through ILSNBVB-SL being approximately four times the value when the HST passes through ILSNB-DL and ILSNBVB-DL. When the HST enters and exits ILSNB-DL and ILSNBVB-DL, the pressure difference between the two sides of the HST is greater than that when the HST enters and exits ILSNBVB-SL, leading to the maximum amplitude of the side force of the HST passing through ILSNB-DL being 1.8 times of the value for ILSNBVB-DL and ILSNBVB-SL.