Numerical Analysis Method for Two-Dimensional Two-Fluid Model Using Control Volume Formulation

A numerical calculation technique for the two-dimensional two-fluid model has been developed. The control volume formulation and non-staggered mesh scheme are employed in order to confirm that solutions satisfy the conservation equations of the two-fluid model. Numerical instability due to the non-staggered mesh is overcome by considering additional flows induced from a local pressure gradient on control volume boundaries. The Godunov method and SIMPLE method are used to estimate the additional flow for compressible and incompressible two-phase flows, respectively. These methods are modified to take the density difference between the phases and the added mass effect into account. The present method has been applied to analyses of two-dimensional two-phase flow discharge from a pipe and phase separation due to gravity in a horizontal circular pipe in order to investigate the capability of dealing with fundamental phenomena of two-dimensional two-phase flow. The present technique enables a small scale computer program to simulate twodimensional two-phase flow and it should be a valuable tool for fundamental study of two-phase flow dynamics.