Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Discrete-element simulation of particle breakage inside ball mills: A 2D
  model   In this paper, the grinding of powder inside a ball mill is studied using the
Bonded Cell Method (BCM) implemented in the framework of Contact Dynamics. In
BCM the parent particles are divided into cells that are glued to one another
until, under the action of external loading, both a cohesion threshold and a
certain distance threshold are reached. Numerical simulations of a rotating
hollow cylinder filled with a mixture of heavy balls and powder crushable
particles were carried out. Systems with balls of different sizes and/or
numbers are compared in terms of the evolution of the powder particle size and
specific surface. We find that, in general, the milling process is increasingly
faster as the ball size increases. But energy dissipation due to increased
collisions between balls slows down the grinding process and makes it
energetically less efficient. On the other hand, when the total volume of balls
is kept constant, the ball size is not relevant for the evolution of particle
breakage except in the limit cases of very small and very large ball sizes.

19
The categories of this paper are: eess
6
The categories of this paper are: astro-ph
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn
21
The categories of this paper are: adap-org
33
The categories of this paper are: plasm-ph
31
The categories of this paper are: ao-sci
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
9
The categories of this paper are: nlin
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
18
The categories of this paper are: econ
7
The categories of this paper are: hep-th
26
The categories of this paper are: bayes-an