An upwind numerical method for two-fluid two-phase flow models

Modeling and numerical simulation of two-phase flow phenomena keep causing complex problems for the development of computer codes dedicated to design and safety studies of nuclear reactors. An upwind numerical method for a six equation two-fluid model is presented based on a linearized Riemann solver. The construction of this approximate Riemann solver uses an extension of Roe's method that has been successfully used to solve gas dynamics equations in aerodynamics problems. As far as the two-fluid model is hyperbolic, this numerical method seems very efficient for the numerical solution of two-phase flow problems. In practice, this new numerical method has proved to be stable on nonstaggered grids and capable of generating accurate nonoscillating solutions for two-phase flow calculations. The scheme was applied both to shock tube problems and to standard tests for two-fluid codes