Turbulence interaction between gas and particle phases has been studied by numerical simulation in axisymmetric sudden-expansion chambers in this paper. A two-fluid model coupled with a k-epsilon-k(p) two-phase turbulence model proposed by the present authors was used in the computations. The predicted axial mean velocity, the turbulence intensity of the single phase (flow without particles) and the particle phase in two-phase flows are in agreement with the experimental data reported by Shahnam and Morris in 1989. Furthermore, predictions show that the particle mass loading strongly modifies gas-phase turbulence but has only a slight effect on particle turbulence. Comparison of the numerical results calculated by different versions of the k-epsilon-k(p) and k-epsilon-A(p) models with the experimental data indicates that the k-epsilon-A(p) model is inadequate and that the k-epsilon-k(p) model can properly predict the gas-particle turbulence in recirculating flows.