**Abstract**

During the last decade the problem of crosswind has developed into an important subject amongst the topics in railway engineering. When high speed trains are exposed to extreme weather conditions such as intense lateral winds, storms and tornadoes, lateral loads acting on the train can cause overturning of the train. This present work analyzed the aerodynamic mechanism of a high-speed train with and without two inclined barriers. A three-dimensional numerical model of a train-barrier-crosswind system is adopted to investigate the effects of inclined angles of barriers on the flow patterns and the aerodynamic coefficients. This perusal surveys the design criteria indispensable for barriers that are installed alongside the tracks to protect the passing trains under strong side winds. By using a numerical code based on Lattice Boltzmann Method (LBM) it is attempted to initially investigate the behavior of airflow behind the barriers. Finally, it is found that the presence of the barriers has a great impact on decreasing the intensity of the air flow above the train. This study's findings could be utilized as a reference for practical usage of barriers in railway transportation.

**Keywords:** train aerodynamic, crosswind, high speed train, barrier, LBM
