Numerical analysis of centrifugal separation behavior during centrifugal casting using particle method

Synopsis : Centrifugal force is applied to a molten metal during a centrifugal casting process. Therefore, grains of primary solidified phase, inclusions or other additional agents are separated if centrifugal force is strong. The centrifugally separated structure is strongly influenced by a relationship between solidification rate of castings and centrifugal separation speed. However, it is difficult to observe or measure what happens in the process because the process is carried out under high temperatures and the material is usually opaque. Therefore, we tried to observe the centrifugal separation behavior during the centrifugal casting process by using 2-phase flow simulation based on MPS (Moving Particle Semi-implicit) method which is one of particle methods. We simulated centrifugal separation behaviors in the process and investigated an influence of density difference between the phases, particle size, viscosity and rotation speed. As a result, the centrifugal separation behavior was well simulated by the particle method, and also well evaluated by Stokes's law by considering an influence of an apparent viscosity increase caused by an error included in the MPS method.