Page 33 - The Combined Finite-Discrete Element Method
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16 INTRODUCTION
Figure 1.22 Gravitational deposition of a pack comprising spheres of two different sizes: 399
large spheres of diameter d = 29.988 mm, and 1992 smaller spheres of diameter d = 14.994 mm;
3
the total solid volume is V = 9.150e−03 m .
0.9
0.8
0.7
0.6
Density 0.5
0.4
0.3
S2a
0.2 S2b
S2c
0.1 S2d
0
0 50 100 150 200 250 300 350
Distance from the bottom (mm)
Figure 1.23 Pack density profiles for gravitational deposition of a pack comprising spheres of two
different sizes: 399 large spheres of diameter d = 29.988 mm, and 1992 smaller spheres of diameter
3
d = 14.994 mm; the total solid volume is V = 9.150e−03 m ; S2a is initial density profile, S2b
and S2c are transient density profiles, and S2 is the final density profile corresponding to the state
of rest.
The gravitational deposition of a pack comprising spheres of three different sizes is
shown in Figure 1.24. The transient and final packing density profile for the same pack
is shown in Figure 1.25, which shows increased final packing density relative to the pack
comprising spheres of two different sizes. It is also noticeable that large particles tend to
segregate, and can be found on the top of the pack.
The gravitational deposition of a pack comprising spheres of four different sphere sizes
is shown in Figure 1.26. Again, some increase in packing density (Figure 1.27), coupled
with segregation of the largest particles, which can be found on the top of the pack,
is observed.
