This work focuses on the numerical modelling and experimental validation of hydrodynamic behaviour a novel 50 kWth indirectly heated bubbling fluidized bed steam reformer. The beds with immersed vertical tubes complex geometries in general have not been thoroughly investigated terms coupled for pilot scale reactors. Therefore, present study contributes to hydrodynamics field, while investigatin...

We present in this Letter experimental results on the bidimensional flow field around a cylinder penetrating into dense granular matter, together with drag force measurements. A hydrodynamic model based on extended kinetic theory for dense granular flow reproduces well the flow localization close to the cylinder and the corresponding scalings of the drag force, which is found to not depend on v...

In a recent article (Forterre & Pouliquen 2001), we have reported a new instability observed in rapid granular flows down inclined planes that leads to the spontaneous formation of longitudinal vortices. From the experimental observations, we have proposed an instability mechanism based on the coupling between the flow and the granular temperature in rapid granular flows. In order to investigat...

Under many conditions, macroscopic grains flow like a fluid; kinetic theory predicts continuum equations of motion for this granular fluid. In order to test the theory, we perform event-driven molecular simulations of a two-dimensional gas of inelastic hard disks, driven by contact with a heat bath. Even for strong dissipation, high densities, and small numbers of particles, we find that contin...

Many features of real granular fluids under rapid flow are exhibited as well by a system of smooth hard spheres with inelastic collisions. For such a system, it is tempting to apply standard methods of kinetic theory and hydrodynamics to calculate properties of interest. The domain of validity for such methods is a priori uncertain due to the inelasticity, but recent systematic studies continue...

– Inelastic grains in a flow under gravitation tend to collapse into states in which the relative normal velocities of two neighboring grains is zero. If the time scale for this gravitational collapse is shorter than inverse strain rates in the flow, we propose that this collapse will lead to the formation of “granular eddies”, large scale condensed structures of particles moving coherently wit...

The paper attempts to give a critical overview of the field of granular flow with attention both to the history and the underlying physics that govern the field. It starts with a discussion of the basic transport mechanisms in a granular flow. It continues with a discussion of contact mechanics – the way that individual particles see each other mechanically. It then discusses the historical lim...