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A computational study of mono-dispersed spherical sedimenting particles has been performed with Eulerian two-fluid model (TFM). The aim was to investigate applicability and accuracy of TFM with proper closure laws from kinetic theory of granular flow (KTGF) for sedimentation studies. A three dimensional cubical box with full periodic boundaries is employed. The volume fraction (ϕ_s) of particles is varied from very low (ϕ_s= 0.01) to dense regimes (ϕ_s= 0.4), for two different types of fluids i.e. gas and liquid. It is observed that the results for liquid-solid sedimentation are in good agreement with simulation studies and experimental correlation of Richardson and Zaki. However, for gas-solid system, results show different behaviour at low volume fractions, which is more pronounced with increasing Stokes number. This can be attributed to inhomogeneous distribution of solid particles in gas phase at dilute concentrations, which causes meso-scale clusters and streamers formation. It is concluded that the ratio of density of particles to density of fluid which appears in Stokes number plays critical role in settling behaviour of particles.