A new method for simulation of comminution process in jet mills Academic Article uri icon

abstract

  • Recently, a computational fluid dynamics–discrete element method (CFD–DEM) model of comminution in a jet mill (Datta and Rajamani [1]) is developed. The model is based on a method previously defined by Kalman et al. [2] in which empirical comminution functions (strength distribution, selection, breakage, and fatigue functions) are implemented. Consequently, an accurate simulation of the size-reduction process is achieved. However, this simulation requires an overlong running time that might prevent its use in practical cases. Therefore, in this paper, we present a new procedure to describe the comminution process in a jet mill that can be applied in any size-reduction system. The new procedure uses the same material functions that are applied to any particle in the mill. However, three additional machine functions are required in order to implement the breakage procedure: impact velocity, frequency distributions, and classification functions. These machine functions are derived from the CFD–DEM simulations of the jet mill, where particle breakage is ignored; accordingly, the running time is considerably reduced. Moreover, once these distributions are defined for a particular mill configuration as a function of particle size and air flow rate, simple and fast simulations can be performed for a variety of operating conditions. Results of the new simulation method are comparable with the jet mill experimental results.

publication date

  • January 1, 2019