![]() Downstream pile had a large impact on the aeolian erosion as it was highly eroded as a result of the impact of the particles emitted from the upstream pile. The emitted mass was experimentally quantified as the difference between the initial and final stockpile weights. The mean field of the wall shear stress distribution and flow pathlines predicted by numerical simulation were associated with the experimental erosion patterns. The contrasting colours enabled the visualisation of the non-erodible sand accumulation. The particles in the piles had a bimodal particle size distribution consisting of sand that was erodible (white) and non-erodible (black) in the investigated velocity range. A wind tunnel experiment was conducted in six configurations: one isolated pile and two successive piles separated by gaps of 0.9h and 1.8h (h is the pile height) oriented to 60° and 90° with respect to the main wind flow direction. The aim of this study was to analyse the impact of wind erosion of successive parallel stockpiles on flow behaviour and particle emissions. The aeolian erosion of stockpiles is affected by changes in airflow patterns due to the pile shape and the presence of nearby piles or buildings. Open storage yards at industrial sites usually comprise several piles of granular materials, representing a particulate matter source that may significantly deteriorate air quality. With the increase in particle diameter, the dust concentration distribution presents the trend of interior hollowing and high-concentration area fragmenting. Under the same starting speed, the dispersion distance of dust decreases with the increase in particle diameter. The increase in particle diameter increases the kinetic energy loss of particles for the fluid. Results show that a high-concentration range of the dust exists near the pile behind the wind direction and may continue to spread to the height due to the influence of a whirlpool, and the dispersion distance and width can increase with the increase in wind speed. Although a large gap exists between the assumption and the real atmospheric environment, this study provides a reference for the evaluation of the pollution scope of blowing dust and prevention and control of pollution. The complex atmospheric environment is simplified as unidirectional wind, and the influence of different wind speeds on the dispersion of particles with diverse sizes in the pile is studied. The dispersion characteristics of dust particles around the pile under the action of unidirectional wind are studied through wind tunnel test and numerical simulation. In this study, a pile of sodium carbonate in a large open-air pile in Weifang, China, is regarded as the research object. Studying the law of dust diffusion in local areas is of great significance for the atmospheric particulate control. To maintain the dust emissions at an acceptably low level, other measures such as spraying with water and crust-forming liquids may still be necessary at higher wind velocities.Ī large amount of dust particles produced by the wind in an open-air pile is one of the important reasons for air pollution. The angle of incoming wind is a key factor influencing effectiveness of both solid and porous windbarriers The proposed placement of porous barriers between the piles has shown to be effective in reducing wind exposure and dust emission. Realistic stockpile geometry with adjacent structures has shown to cause wind velocity distributions, which are not consistent with the most studied cases of regular pile shapes and layouts. ![]() On the other hand, pile rearrangement has little effect and may not be practical for implementation. Comparison of selected cases shows a positive, although limited effect of porous fences and barriers on reduction of local velocities and consequently dust erosion rate. ![]() Results from numerical modelling were used in the USEPA model to determine dust emission factors. Wind velocity fields above the piles were calculated for the current stockpile layout and for several modified cases with rearranged piles and added porous barriers. Dust lifting presents a serious environment and health hazard, thus the main objective of our study was to propose efficient measures for wind erosion reduction A numerical model of the stockpile was created using the computational fluid dynamics (CFD) software. This paper investigates the dust lifting phenomenon at the coal and iron ore stockpile at the Port of Koper, Slovenia. ![]()
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