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Dust Dispersion Characteristics of Open Stockpiles and the Scale of Dust Suppression Shed

The storage of bulk materials in open yards can easily lead to contamination in the form of suspended particles. The creation of enclosed spaces for open yards is an effective measure to stop the dispersion of dust to the outside. In this study, a reliable numerical model was developed to calculate the impact range of dust dispersion using the concentration–velocity distribution of pollutants based on the DPM-CFD simulation, and validated by field measurement data. Then, the hazard distance was defined as the basis for determining the boundary of the closed shed. Finally, we determined the dimensions of the boundaries by a comprehensive analysis of the structure and materials of the closed shed. Our results demonstrated that the most unfavorable wind speed determines the maximum concentration of dust at a height of 1.5 m. As a result, hazard distance thresholds are obtained to be 63.5 m and then the shed boundary dimensions are calculated to be 127 m. Our studies can provide some theoretical basis for the construction of closed sheds in field yards.