A hybrid numerical model based on the finite element (FEM) and the discrete element methods (DEM) has been developed to predict the stress and velocity fields for particulate materials during discharge from bins. THe FEM was used to model the particulate solid as a continuum. In regions where the bulk solid stops to be-have as a continuum, such as in the lower part of a hopper near the outlet and in regions where there are large shear deformations such as at the intersection of a vertical wall and a hopper wall, the DEM was used as the preferred procedure. A model for combining the two methods is presented. An algorithm for the combined model is developed. A comparison between the numerical and the experimental results shows that the model simulation has the ability to predict accurately wall pressures and flow velocities in bins. The application of the hybrid model to a parametric study involving bin geometry and wall friction indicates that the friction between stored material and bin wall is the most important factor affecting wall pressure throughout the bin.
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