Prediction model for the migration trajectory and velocity of ore-rock dispersions in an orepass storage section

For the accurate prediction of the migration state of ore-rock dispersions in the ore pass storage section, a prediction model of an ore pass trajectory and velocity was established by taking the orepass structure, which coincided the centerlines of the ore drawing funnel, and the orepass as the research objects. First, during the silo unloading process, the movement law of ore-rock dispersions in the ore-storage section was analyzed according to the similarity of the particles’ movement characteristics and the flow characteristics of an ideal fluid flow unit. Next, the ore-rock migration network was established based from the flow network concept and the Beverloo empirical formula. Analysis was then conducted on the relationship between the section and the velocity of the ore-rock movement in the ore-storage section of ore pass. Finally, under certain assumed conditions, the displacement equation, the migration trajectory, and the velocity of the ore-rock moving in the ore-storage section were established according to the distribution characteristics of streamline and equipotential surface. Results reveal that after entering the ore-storage section of the ore pass, the ore-rock will pass through two speed zones: (1) a uniform speed zone leading to a uniform linear downward motion and (2) a variable speed zone leading to a variable speed curve motion. When the dip angle of the ore draw-hole is small, an “empty ring effect” is achieved, where no displacement of the lower ore-rock is observed. Finally, the quality of the ore-rock drawing-out in a unit time is found to be equal to that of the ore-rock passing through the same equipotential surface. The predicting model reveals the dependency of the ore-rock migration state in the uniform speed zone with a number of parameters such as the diameter of the section of ore-storage and ore-discharge, ore-rock particle size. Conversely, the ore-rock migration state in the variable speed zone is mainly related to the ore-rock’s location and the inclination angle of ore draw-hole.