Mechanisms of Fragmentation in Ultrasound Assisted Impact Comminution

نویسندگان

  • FALK K. WITTEL
  • HANS J. HERRMANN
  • Falk K. Wittel
  • Hans J. Herrmann
چکیده

Abstract. Impact fragmentation is the underlying principle of comminution milling of dry, bulk solids. Unfortunately the outcome of the fragmentation process is more or less determined by the dimensionality of the impactor and it’s impact velocity, prohibiting the adjustment of desired fragment distributions. By modifying target shapes or impact angles, differences in the fragment mass distributions can be obtained, however the overall picture does not change significantly. Fragmentation is basically the destruction in the wake of the interfering shock waves. Therefore manipulating traveling shock waves and adding energy to the system during it’s fragmentation could be a promising approach. In a former study we explored mechanisms in impact fragmentation of spheres, using a three-dimensional Discrete Element Model (DEM). In this work we study how single sphere fragment when impacted on a planar vibrating target.

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تاریخ انتشار 2009