The hydrodynamic behaviour of dispersed gas-solid flow in a riser is simulated using the two-fluid model formalism, with complementary information from the kinetic theory of granular media to represent the transport proper-ties of the solid phase, The specific source terms of phases interaction are described in the momentum transport and fluctuating kinetic energy equations of each phase. The simulation results show the highly unsteady state of the flox. Inspection of the kinematic parameters fluctuations confirms these results. The core-annulus structure and the existence of clusters are well predicted.