A numerical study was performed for the influence of various physical parameters on the hydrodynamics of gas-solid two-phase flow in a precalciner. An Eulerian continuum two-fluid model is applied for both the gas phase and the solid phase. The transport properties of the solid phase are represented using kinetic theory of granular flow. The unsteady gas and solid flow behavior, affected by the major concerned physical parameters in the precalciner, were presented from the computer simulations. The dilute annulus-dense core flow structure of particles was predicted. The influences of the velocities of the primary and secondary jets, secondary jet arrangement, and particle-particle coefficient of restitution on the hydrodynamics of solid flow are discussed. (C) 2004 Elsevier B.V. All rights reserved.