2.3.1 Wind tunnel description
The wind tunnel was provided by the Laboratory of Wind and Sand Environment and Engineering of the Beijing Normal University. The wind tunnel has a total length of 34.4 m. A high-power fan can adjust the wind speed between 1 m/s and 40 m/s. The middle part of the wind tunnel is used to place experimental materials. It is surrounded by toughened glass and its cross-section is a rectangle of 0.6 m×0.8 m. The pitot tube is used to measure the wind speed at different points in the tunnel. In the study of wind erosion and particulate matter emission, the abrader sand was not introduced into the wind flow upwind, but was directly measured the erosion amount of samples under different BSCs. In order to determine the amount of wind erosion, the tunnel uses an electronic scale (accuracy: 0.0005 g) to weight the undisturbed soil collection box.