A multiphase tracking method for modelling the interfacial flow of two immiscible liquids in mixing process H. Tang ∗ , J.Y. Tu ∗ , L.C. Wrobel † , 27 September 2004 Abstract This paper presents an interface tracking method for modelling the flow of immiscible metallic liquids in mixing processes. The methodology can provide an insight into mixing processes for studying the fundamental morphology development mechanisms for immiscible interfaces. The VOF method employed here utilises the piecewise linear for interface construction scheme as well as the continuum surface force algorithm for surface force modelling. A model coupling numerical and experimental data is established. The main flow features in the mixing process are investigated. It is observed that the mixing of immiscible metallic liquids is strongly influenced by the viscosity of the system, shear forces and turbulence. The numerical results show good qualitative agreement with experimental results, and are useful for optimising the design of mixing casting processes. 1 Introduction Casting immiscible engineering alloys is a challenging problem due to metallic and hydrodynamic phenomena which take place during the process; various research efforts are still in progress to develop a process methodology for obtaining a fine and uniformly dispersed microstructure. Evidence shows that the liquid-liquid decomposition and spatial behaviour in the molten state dominate the solidified microstructure of immiscible alloys. However, the hydrodynamic behaviour in the molten state is not well * School of Aerospace, Mechanical and Manufacturing Engineering, RMIT University, Victoria, 3083, Australia † School of Engineering and Design, Brunel University, Uxbridge, Middlesex, UB8 3PH, UK