Granular material flow regime map for planar silos and hoppers

This study presents a new theoretical model for granular materials flow regimes during discharge from wedge-shape (planar) silos. The new model takes into account the influence of granular material properties, material height, bin and hopper geometrical dimensions and consider the possible difference between the bin and the hopper wall friction coefficients. In addition, the model allows to found an appropriate transition between mass flow and two kinds of funnel flow regimes. By comparing the new model assessments to experimental results, which were found in the literature, good agreement was achieved. Based on the new model equations a generalized flow regime map was presented. The proposed generalized flow regime map should help designers to increase accuracy and flexibility in the granules flow regime assessment and therefore might improve significantly the process efficiency.