Page 244 - The Combined Finite-Discrete Element Method

COMBINED FINITE-DISCRETE ELEMENT SYSTEMS 227

Figure 6.17 Subsequent bouncing from the top side of the box followed by bouncing from the
bottom side of the box.

Figure 6.18 Left hand rod is slightly inclined.

Sensitivity to initial conditions is also well established in experimental investigations
of combined finite-discrete element systems. In Figure 6.21, the experimental results of
the gravitational deposition of wooden cubes into a glass box is shown. The cubes are
dropped one-by-one through a regular grid at the top of the box. In total, 648 cubes
were dropped. The same experiment was repeated three times, with the same initial and
boundary conditions and experimental setup.
One would expect exactly the same results to be obtained in each repeat of the experi-
ment. The final states of rest for all three repeats of the experiment are shown Figure 6.21.
It is evident that the results of the three exactly identical experiments are not the same.
There is overall similarity of the results, however at a detailed level, the three results
differ considerably.