In granular flows, when the solid volume fraction is large, the dynamic behaviour of particles becomes controlled by frictional effects. Theoretically these effects can not be taken into account in an Eulerian approach, based on the kinetic theory of granular flows, because the inter-particle contact times are long. However, in the literature several empirical models have been proposed which introduce a frictional pressure and viscosity. In the paper, these models are first compared on a simple case of sheared dense granular flows in order to analyze the individual behavior of each model. Second, the models have been implemented in an Eulerian solver and numerical simulations have been performed of an experiment of bin discharge. The results show that for large diameter, the solid mass flow rate is well predicted, while it is systematically underestimated when the ratio between the injector diameter and the diameter of particles is small
