Large-eddy simulations have been conducted for two-phase flow (water and air) in a hydrocyclone using Two-Fluid (Euler–Euler) Volume-of-Fluid (VOF) models. Subgrid stresses are modeled dynamic eddy–viscosity model, results compared to those the Smagorinsky model. The effects of grid resolutions on mean turbulence statistics thoroughly investigated. Five block-structured grids 0.72, 1.47, 2.4, 3...