Dense fluid-particle flow occurs in many industrial applications, such as fluidized bed technology. To model these flows, statistical approaches are developed and, since quite recently, particle resolved simulations may be used to support the validation and the development of models. The viscous penalty method is used here to track moving solid particles coupled with the Direct Numerical Simulation (DNS) of the interstitial fluid flow. Particle-particle collisions are taken into account by Discrete Element Method (DEM) as well as the lubrication forces. 3D direct numerical simulations have been carried out of a periodic Couette flow were performed for finite Stokes number and moderate Reynolds number values for dense flows ranging from 5 to 30%. The results show a particle accumulation - at the centre or at the wall- according to the Stokes number and particle volume fraction. The production, diffusive, collisional and fluid interaction terms are analyzed for the momentum equation and particle kinetic stress equation as well.