In the present work, turbulent two-phase flows of air and water are numerically simulated through a smooth area expansion/restriction with a constant opening angle. To model the multiphase flow, a two-fluid approach is adopted in which two sets of governing equations are solved simultaneously for continuous and dispersed phases and the coupling between these phases is forced by proper source terms. An extended version of two equation k-epsilon turbulence model is used and the numerical result was validated in comparison to previously published experimental data. The effect of volumetric void fraction, Reynolds number and the opening angle is examined on the pressure distribution across the flow domain. (C) 2015 Elsevier Ltd. All rights reserved.