In this study, the unsteady Reynolds-averaged Navier–Stokes algorithm coupled with the Discrete Phase Model (DPM) was used to study the accumulation of snow in the bogie region of a high-speed train under crosswind conditions. Moreover, the impact of active blowing schemes on the airflow around the bogie and the dynamics and deposition of snow particles were also assessed. According to the results: in the crosswind environment, active blowing changes the flow field in the bogie area, reducing the flow of air coming from the windward side and bottom of the bogie. The trajectory of snow particles carried by crosswinds is modified due to the reduced airflow into the bogie region. With no active blowing, snow accumulation is mainly concentrated in the bogie cavity, frame, and primary suspension; while it is reduced by nearly an order of magnitude as soon as blowing is enabled. Blowing speeds need to be distributed appropriately in order to achieve the best possible snow protection. Continuously increasing the blowing speed on one side does not improve the amount of snow in the bogie region. The optimal condition for snow prevention of the entire train is achieved with a windward side blowing speed of 4 m/s and a leeward side blowing speed of 6 m/s, resulting in a snow reduction rate of 95.6%. Moreover, higher blowing speeds on the leeward side are beneficial for mitigating snow accumulation in the bogie region.

The large number and dense layout of rail fastening can significantly affect the aerodynamic performance of trains. Utilizing the Improved Delayed Detached Eddy Simulation (IDDES) approach based on the SST (Shear Stress Transport) k-ω turbulent model, this study evaluates the effects of the rail fastening system on the aerodynamic force, slipstream and train wake under crosswind conditions. The results indicate that in such conditions, compared to the model without rails, the rail and the fastening system reduce the drag force coefficient of the train by 1.69%, while the lateral force coefficients increase by 1.16% and 0.87%, respectively. The aerodynamic force can be considered virtually unchanged within the error allowance. However, the rail and the fastening system cause an inward shift of the negative pressure center on the leeward side of the train. The peak slipstream velocity near the ground in the rail and rail fastening system model is significantly lower than that in the situation without rails. Additionally, the rail and the fastening system not only induce two displacements in the vortex structure of the train but also accelerate the dissipation of shedding vortex and the rapid decrease of turbulent kinetic energy.