(622f) Kinetic Theory of Rough Spheres Apply to Gas-Solids Risers

Kinetic theory of rough spheres is proposed for flow of dense, slightly inelastic, slightly rough sphere with the consideration of gas-solid interactions. The fluctuation kinetic energy of particles is introduced to characterize the random motion of particles as a measure of the translational and rotational velocities fluctuations. The transport equation of kinetic energy is proposed considering the redistribution of particle kinetic energy between the rotational and translational modes and kinetic energy dissipation by collisions. The solid pressure and viscosity are obtained in terms of the particle roughness and restitution coefficient. The partition of the random-motion kinetic energy of inelastic rough particles between rotational and translational modes is shown to be strongly affected by the particle restitution coefficient and roughness. Hydrodynamics of gas-solid risers are numerically simulated on the basis of the kinetic theory for flow of rough spheres. Computed profiles of particles are in agreement with the experimental measurements in a riser. The effect of roughness on the distribution of energy dissipation, kinetic energy and viscosity of particles is analyzed. Present investigations are supported by NSFC through Grant No. 51390494 and 51176042.