Prevent sand accumulation under the windbreak wall along railways in strong wind areas

The Lanxin High-Speed Railway is the world's first high-speed railway to pass through a strong wind region. Many windbreaks were installed along the railway line to reduce the adverse effects of wind on passing trains. The windbreak wall blocks strong wind, reduces the velocity of sand particles, and minimizes sand accumulation on the track. This paper proposes a solution based on fluid mechanics and the two-phase flow of wind and sand to reduce sand accumulation on railway tracks. Wind tunnel experiments and numerical simulations are conducted for three scenarios: the existing windbreak wall and a 45-degree inclined board installed at the wall's top or the leeward side. The results show that the sand accumulation and wind speed are higher on the windward side. The largest sand accumulation occurs when the 45-degree inclined plate is installed at the top and the wind speed is 15 m/s. The sand accumulation on the track is the lowest, the negative wind speed is the highest when the 45-degree inclined plate is located at the top on the windward side, and the wind speed is 30 m/s. Sand accumulation on the track can be minimized by taking advantage of the highly turbulent area. The sand particle size on the actual track is lower than the average sand particle size at the start of the sand bed. Our results can be used to optimize measures to prevent or minimize sand accumulation in railway lines and towns in windy areas and mitigate desertification.