• Increasing suspension gap from 10 mm to 30 mm reduces head car lift by 12.43% and increases drag by 10.98%.
• The tail car experiences the highest aerodynamic drag and underbody temperatures due to airflow deceleration.
• U-shaped track constrains flow, creating strong vortex structures that significantly affect aerodynamic performance.
• IDDES simulations reveal unique underbody drag and aerothermal distribution patterns for HTS maglev trains.