A Novel Numerical Method for Turbulent, Two-Phase Flow

A novel approach to the simulation of isothermal, turbulent two-phase (liquid/vapour) flow is presented. The two-phase nature of the flow is modeled by means of a diffuse-interface concept and of the Korteweg tensor of capillary forces at the interface, so that a single system of compressible Navier-Stokes equations can be written for the whole flow domain. A Van der Waals equation of state is also included to account for the variation of pressure with density at the given value of temperature. After explanation of a stable numerical method, results of a classic benchmark problem are shown. Next, subgrid terms related to the nonlinear pressure and capillary terms are studied by means of an a priori analysis based on DNS results, and a subgrid model for these terms is proposed.