
		HOPPER

We would like to understand a little better the  outflow  from  a
hopper  which  is  very  frequently  used in industrial setups to
store base materials for processing. The walls of the hopper  are
flat  but  the  inclined side walls are at an angle of 60 degrees
and made of small balls to account for surface roughness.


One can choose two different initial configurations:

a) all particles are of the same size as the wall particles

b) particles have a Gaussian size distribution around the size of
the wall particles


In principle, the configuration from a) is already  in  a  stable
configuration but the ones obtained from b) do have to be equili-
brated by STARTING the simulation from the CONTROLS menu and mon-
itoring  the kinetic energy shown in the graph area at the bottom
of the window. If the energy is low enough (smaller than 1  seems
reasonable)  and  the  particles  do not move any more, one could
save the configuration for later use from the  FILE  menu  and/or
OPEN the shutter to start the outflow sequence.

In this simulation, the colors are chosen to be  proportional  to
the  kinetic  energy of the particles and the color code is given
in the spectrum on the side.

/*
	MolecularDynamics;
	Forces;
	Vibration;
	Billiard;
