Assessment of crosswind safety of a 400 km/h high-speed train through reduced-scale wind tunnel testing.*

South Korea is conducting research to operate a high-speed train (HST) with a maximum speed of 400 km/h in 2034 [1]. As the speed of a HST increases, the possibility of overturning due to crosswind increases [2], so it is necessary to assess crosswind safety when introducing a new HST. 

In this study, the aerodynamic coefficient was measured to evaluate the crosswind safety of the HST through reduced-scale wind tunnel test. Wind tunnel testing was conducted in Low-Speed ​​Wind Tunnel (LSWT) of Korea Aerospace Research Institute, where the specifications were satisfied with the requirements in EN 14067-6. 4.3% reduced-scale model being designed with a maximum speed of 400 km/h was installed on a split plate equipped with turntable located 1 m above the floor of the test section to prevent boundary layer disturbance. The turntable was rotated from 0° to 90°, and the tests were performed at the maximum wind speed of LSWT. Forces and moments were measured by using a 6-axis load cell, and the rolling moment coefficient around the leeward rail (C_mx,lee) to evaluate the crosswind safety was calculated. As a result, C_mx,lee of the present HST model showed 8% lower than that of KTX-Cheongryong, currently in commercial operation with a maximum speed of 320 km/h, implying that the crosswind safety has been improved for the newly designed model.