ABSTRACT
The numerical simulation was carried out based on Fluent. Taking the Tengger Desert section crossing the newly built Wuhai-Maqin Expressway as the research area, the highway subgrade under different section parameters was simulated and analyzed, and the flow field distribution and sediment accumulation characteristics around the subgrade under different section parameters were revealed, to provide the basis for the design of highway section in desert areas. The numerical simulation results show that after the airflow enters the flow field, there are partitions near the subgrade, and the deceleration zone, acceleration zone, high-speed zone, low-speed zone, turbulence zone, and recovery zone are generated from the toe of windward slope, shoulder of windward slope, shoulder of leeward slope, and toe of leeward slope. The horizontal velocity distribution of aeolian sand flow on the subgrade surface is ‘W’, and the vertical velocity distribution is ‘M’. Under different slope gradient, the greater the subgrade slope, the more likely it is to produce backflow in the leeward side, prone to sand accumulation. The higher the subgrade height is, the stronger the blocking effect of subgrade on wind speed is, and the larger the vortex area generated by leeward slope is, which is not conducive to the sediment transport effect of the highway.
