Junsun Ahn

Surrogate-based multi-objective nose shape optimization for 400 km/h-class high-speed trains under open-air, crosswind, and tunnel operations

Abstract This study presents a surrogate-based multi-objective nose shape optimization for a 400 km/h-class high-speed train, considering normal open-air, crosswind open-air, and tunnel-related scenarios. The KTX-Cheongryong nose shape is parameterized using Bézier curves and a s...

Aerodynamic performance of combined bogie fairings in an 8-car high-speed train

Aerodynamic drag accounts for 75%–80% of the total running resistance of high-speed trains operating above 300 km/h, and the bogie region significantly contributes to this drag due to its complex separated flow structures. This study investigates the aerodynamic performance and d...

Experimental and numerical analysis of aerodynamic drag reduction of high-speed train: impact of nose, bogie fairing and roof apparatus variations

Assessing aerodynamic modifications in high-speed trains requires quantifying drag reduction relative to previous designs and evaluating the improvement potential of an integrated configuration. This study investigated three-car configurations of the KTX-Cheongryong and HSEMU-370...