MetaResource

To address the limitation that traditional coal flow calculation methods based on the sectional average-velocity assumption cannot reflect the non-uniform velocity distribution of coal flow in the middle trough of scraper conveyors, this paper proposes a coal flow calculation method based on sectional velocity-domain statistics. In this method, the non-uniform velocity field obtained from discrete element method (DEM) simulations is converted into area-based velocity-domain parameters, and these parameters are further combined with scraper structural parameters to establish an explicit coal flow calculation model. This provides a computational basis for conveying capacity evaluation and operating parameter matching of scraper conveyors. Firstly, a coal flow transport model for the middle trough of three scraper conveyor width models (SGB800, SGB1000, and SGB1250) was established based on the discrete element method. The velocity distribution characteristics of coal flow within the conveyor cross-section were systematically analyzed under different scraper chain speeds and coal pile heights. Based on the differences in chain speeds, the sectional velocity was divided into domains, and the area of each velocity zone was statistically analyzed. The representative velocity for each zone was used to perform an equivalent calculation of the indirect transport volume. Additionally, a direct transport volume model was established in conjunction with scraper structural parameters, thereby forming a coal flow calculation expression applicable to mainstream trough widths, chain speeds, and coal pile height conditions. Finally, the calculation results were verified through scaled experiments. The results showed that the calculated values were in good agreement with the experimental results, with the maximum error in the experimental comparison not exceeding 10%. This provides a reliable theoretical and engineering calculation method for the evaluation of scraper conveyor capacity, parameter matching, and operational safety analysis.