
		VIBRATION

A common phenomena observed in  granular  materials  is  particle
size  segregation.  I.e.,  that  the larger particles move to the
surface under vibration of the bottom plate. If  the  density  of
the  larger particle(s) is smaller than that of the smaller ones,
the effect is clearly understandable due to  Archimedes'  princi-
ple.  But  for  a configuration of equal density or even when the
density of the larger particle(s) is slightly larger than that of
the  smaller  ones one can observe size segregation. The speed of
this phenomena depends on a lot  of  different  parameters,  e.g.
shape,  density,  but  the  most crucial driving mechanism is the
difference in particle diameter.

One can choose two different setups, one with one large  particle
and  the second one with two large particles. The colors are pro-
portional to the velocities of the particles where the big one(s)
are not filled to make them clearer visible.

Unfortunately, the effect is not clearly visible for  the  confi-
guration  since the borders are to close and the number of parti-
cles is not enough. But this will be taken care of in the future.

/*
	MolecularDynamics;
	Forces;
	Hopper;
	Billiard;
