Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Analysis of the flow of granular materials through a screw conveyor   Screw conveyors are widely employed in industry for the bulk transport of
particulate materials. Several studies have attempted to correlate the
discharge rate with the rotation speed of the screw via experiments and
particle dynamics simulations. However, a detailed mechanical model that would
assist in the optimal design of screw conveyors has not been attempted. In this
study, we first construct a simple model that assumes the entire granular
medium to move as a rigid body sliding along the surfaces of the screw and
barrel. By enforcing the balances of linear and angular momentum to a suitably
chosen continuum element, we show that under certain limiting conditions, the
discharge rate for a given angular velocity and screw geometry can be obtained.
Further, we show that the discharge can be maximized by setting the ratio of
the pitch to barrel diameter to a particular value. We then study the detailed
flow within the conveyor using the Discrete Element Method, which reveals that
a significant fraction of the material exhibits solid body motion, in agreement
with the simple model. We assess the effect of relaxing the limiting conditions
employed in the model, thereby determining the connection between the friction
at the walls and the kinematics of flow. Finally, the trend in variation of
average axial velocity with the pitch to barrel diameter ratio in the presence
of gravity is compared with that from our model and simulations in the absence
of gravity. We observe that both the trends are qualitatively the same
indicating that the dependence of average axial velocity on the geometry of the
conveyor is not altered by the introduction of gravity.

33
The categories of this paper are: plasm-ph
20
The categories of this paper are: acc-phys
15
The categories of this paper are: nucl-ex
34
The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
21
The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
8
The categories of this paper are: hep-ex
24
The categories of this paper are: dg-ga
26
The categories of this paper are: bayes-an
13
The categories of this paper are: quant-ph
1
The categories of this paper are: cs
17
The categories of this paper are: q-fin
16
The categories of this paper are: stat