Masahiko Uekusa

Behavior of Three Kinds of Particles in Rotary Barrel with Planetary Rotation

Barrel polishing is an extremely efficient processing method for the surface smoothing treatment of a large number of workpieces. However, workpieces and grinding materials may separate depending on processing conditions. Since barrel polishing is carried out while mixing workpieces and grinding materials, the occurrence of segregation should be avoided. The processing conditions inside a planetary barrel which simultaneously rotates around the horizontal axis and revolves around the vertical axis include many unknown factors as well as the occurrence of segregation. The motions of workpieces and grinding materials in this barrel are basically the same as those of particles undergoing planetary rotation in a cylindrical barrel. However, in order to calculate the behavior of a large number of particles, a numerical method that can be applied to a discrete body is necessary. Therefore, in this study, two kinds of particles of different materials and sizes were filled into a planetary barrel, and the behavior of those particles was examined through experiments and simulations using the Discrete Element Method (DEM). As a result, it was demonstrated that certain combinations of length and inside diameter of the rotary barrel could prevent the segregation.