Using both a continuum Navier-Stokes solver, with the mu(I)-flow-lawimplemented to model the viscous behavior, and the discrete Contact Dynamicsalgorithm, the discharge of granular silos is simulated in two dimensions fromthe early stages of the discharge until complete release of the material. Inboth cases, the Beverloo scaling is recovered. We first do not attemptquantitative comparison, but focus on the qualitative behavior of velocity andpressure at different locations in the flow. A good agreement is obtained inthe regions of rapid flows, while areas of slow creep are not entirely capturedby the continuum model. The pressure field shows a general good agreement. Theevolution of the free surface implies differences, however, the bulkdeformation is essentially identical in both approaches. The influence of theparameters of the mu(I)-flow-law is systematically investigated, showing theimportance of the dependence on the inertial number I to achieve quantitativeagreement between continuum and discrete discharge. The general ability of thecontinuum model to reproduce qualitatively the granular behavior is found to bevery encouraging.
展开▼