The gas-solids flow behavior was predicted by means of a hydrodynamic model of dense gas-solid flow in spouted beds. Constitutive equations describing the particle interactions and friction of particles and viscosity were incorporated into a hydrodynamic simulation computer program. The effect of operating conditions (inverted cone inclination and gas spouting velocity) on particle velocity and concentration in the three zones of spouted beds: spout

annulus and fountain were numerically studied. Both vertical and horizontal particle velocities increased with increasing spouting gas velocity in the spouted region. The diameter of the spout increases with decreasing inclination. As inclination is greater than 60°

there is a neck near the jet.